P

P P para; peta-; phosphate (group); phosphorus; posterior; premolar; proline; pupil.

P P power; pressure.

P₁ P₁ parental generation.

P₂ P₂ pulmonic second sound.

P_CO2 P_CO2 the partial pressure of carbon dioxide (carbon dioxide tension).

P_O2 P_O2 the partial pressure of oxygen (oxygen tension).

p p pico-; proton; the short arm of a chromosome.

p–p– para- (2).

PA PA physician assistant; posteroanterior; pulmonary artery.

Pa Pa pascal; protactinium.

PAB, PABA PABA p-aminobenzoic acid.

pacemaker stimulateur 1. that which sets the pace at which a phenomenon occurs. 2. the natural cardiac pacemaker or an artificial cardiac pacemaker. 3. in biochemistry, a substance whose rate of reaction sets the pace for a series of related reactions. artificial cardiac p. s. cardiaque artificiel a device designed to reproduce or regulate the rhythm of the heart. It is worn by or implanted in the body of the patient, is battery-driven, is usually triggered or inhibited to modify output by sensing the intracardiac potential in one or more cardiac chambers, and may also have antitachycardia functions. Many are designated by a three to five letter code used to categorize them functionally. cardiac p. s. cardiaque a group of cells rhythmically initiating the heartbeat, characterized physiologically by a slow loss of membrane potential during diastole; usually it is the sinoatrial node. demand p. s. cardiaque à la demande an implanted cardiac pacemaker in which the generator stimulus is inhibited by a signal derived from the heart’s electrical activation (depolarization), thus minimizing the risk of pacemaker-induced fibrillation. dual chamber p. s. cardiaque double chambre an artificial pacemaker with two leads, one in the atrium and one in the ventricle, so that electromechanical synchrony can be approximated. ectopic p. foyer ectopique any biological cardiac pacemaker other than the sinoatrial node; it is normally inactive. escape p. foyer ectopique de secours an ectopic pacemaker that assumes control of cardiac impulse propagation because of failure of the sinoatrial node to initiate one or more impulses. fixed-rate p. pacemaker asynchrone an artificial cardiac pacemaker set to pace at only a single rate. rate responsive p. s. cardiaque sensible à la fréquence an artificial cardiac pacemaker that can deliver stimuli at a rate adjustable to some parameter independent of atrial activity. runaway p. s. cardiaque hors-contrôle a malfunctioning artificial cardiac pacemaker that abruptly accelerates its pacing rate, inducing tachycardia. secondary p. s. cardiaque secondaire ectopic p. single chamber p. s. cardiaque monochambre an implanted cardiac pacemaker with only one lead, placed in either the atrium or the ventricle. wandering atrial p. s. cardiaque atrial erratique a condition in which the site of origin of the impulses controlling the heart rate shifts from one point to another within the atria, almost with every beat.

pachy– pachy- word element [Gr.]. thick.

pachyblepharon pachyblépharose thickening of the eyelids.

pachycephaly pachycéphalie abnormal thickness of the bones of the skull. Adj.: pachycephalic.

pachycheilia pachychéilie thickening of the lips.

pachydactyly pachydactylie megalodactyly.

pachyderma pachydermie abnormal thickening of the skin. Adj.: pachydermatous.

pachydermatocele pachydermocèle plexiform neuroma attaining large size, producing an elephantiasis-like condition.

pachydermoperiostosis pachydermopériostose pachyderma of the face and scalp, thickening of the bones of the distal limbs, and acropachy.

pachyglossia pachyglossie abnormal thickness of the tongue.

pachygyria pachygyrie macrogyria.

pachyleptomeningitis pachyleptoméningite inflammation of the dura mater and pia mater.

pachymeningitis pachyméningite inflammation of the dura mater.

pachymeningopathy pachyméningopathie noninflammatory disease of the dura mater.

pachymeninx pachyméninge pl. pachymeninges Dura mater.

pachynsis épaississement anormal an abnormal thickening. Adj.: pachyntic.

pachyonychia pachyonychie abnormal thickening of the nails. p. congenita p. congénitale a rare, congenital, dominantly inherited disorder marked by thickening of nails, hyperkeratosis of palms and soles, and leukoplakia.

pachyperiostitis pachypériostose periostitis of the long bones resulting in abnormal thickness of affected bones.

pachypleuritis pachypleurite 1. fibrothorax. 2. pleural fibrosis.

pachysalpingitis pachysalpingite chronic salpingitis with thickening.

pachysalpingo-ovaritis pachysalpingo-ovarite chronic inflammation of the ovary and uterine tube, with thickening.

pachytene pachytène the third stage of prophase in meiosis I, during which synapsis is complete and genetic material may be exhanged by crossing over.

pachyvaginitis pachyvaginite chronic vaginitis with thickening of the vaginal walls.

pacing entraînement, stimulation setting of the pace. asynchronous p. e. asynchrone cardiac pacing in which impulse generation by the pacemaker occurs at a fixed rate, independent of underlying cardiac activity. burst p. e. par explosion overdrive p. cardiac p. e. cardiaque regulation of the rate of contraction of the heart muscle by an artificial cardiac pacemaker. coupled p. s. couplée a variation of paired pacing in which the patient’s natural depolarization serves as the first of the two stimuli, with the second induced by an artificial cardiac pacemaker. diaphragm p., diaphragmatic p. e. diaphragmatique electrophrenic respiration. overdrive p. e. électrosystolique rapide the process of increasing the heart rate by means of an artificial cardiac pacemaker in order to suppress certain arrhythmias. paired p. s. appariée cardiac pacing in which two impulses are delivered to the heart in close succession, to slow tachyarrythmias and to improve cardiac performance. ramp p. s. en rampe cardiac pacing in which stimuli are delivered at a rapid but continually altering rate, either from faster to slower (rate decremental or tune down), from fast to faster (cycle length decremental or ramp up), or in some cyclic combination of increasing and decreasing rates; used to control tachyarrhythmias. synchronous p. e. synchrone cardiac pacing in which information about sensed activity in one or more cardiac chambers is used to determine the timing of impulse generation by the pacemaker. underdrive p. e. électrosystolique lent a method for terminating certain tachycardias by means of slow asynchronous pacing at a rate not an even fraction of the tachycardia rate.

pack 1. enveloppement treatment by wrapping a patient in blankets or sheets or a limb in towels, either wet or dry and hot or cold; also, the blankets or towels used for this purpose. 2. tamponnement a tampon.

packer pince à pansement an instrument for introducing a dressing into a cavity or a wound.

packing méchage, tamponnement the filling of a wound or cavity with gauze, sponges, pads, or other material; also, the material used for this purpose.

paclitaxel paclitaxel an antineoplastic that promotes and stabilizes polymerization of microtubules, isolated from the Pacific yew tree (Taxus brevifolia); used in the treatment of advanced ovarian or breast carcinoma, non-small cell lung carcinoma, and AIDS-related Kaposi sarcoma.

PACU SSPI postanesthesia care unit; see under unit.

pad tampon a cushionlike mass of soft material. abdominal p. t. abdominal a pad for the absorption of discharges from abdominal wounds or for packing off abdominal viscera to improve exposure during surgery. buccal fat p. boule graisseuse de Bichat sucking p. dinner p. t. pour corset plâtré a pad placed over the stomach before a plaster jacket is applied; the pad is then removed, leaving space under the jacket to accommodate expansion of the stomach after eating. infrapatellar fat p. corps adipeux infrapatellaire a large pad of fat lying behind and below the patella. knuckle p’s coussinets des phalanges nodular thickenings of the skin on the dorsal surface of the interphalangeal joints. retromolar p. coussin rétromolaire a cushionlike mass of tissue situated at the distal termination of the mandibular residual ridge. sucking p., suctorial p. bourrelet de succion a lobulated mass of fat that occupies the space between the masseter and the external surface of the buccinator; it is well developed in infants.

padimate O padimate O a substituted aminobenzoate used as a sunscreen, absorbing UVB rays.

pae- pae- for words beginning thus, see those beginning with pe-.

PAF FAP platelet activating factor.

-pagus -pagus word element [Gr.]. conjoined twins.

PAH, PAHA PAH p-aminohippuric acid.

PAI IAP plasminogen activator inhibitor.

pain douleur a feeling of distress, suffering, or agony, caused by stimulation of specialized nerve endings. bearing-down p. d. expulsives pain accompanying uterine contractions during the second stage of labor. false p’s fausses d. ineffective pains resembling labor pains, not accompanied by cervical dilatation. growing p’s d. de croissance recurrent quasirheumatic limb pains peculiar to early youth. hunger p. faim douloureuse pain coming on at the time for feeling hunger for a meal; a symptom of gastric disorder. intermenstrual p. d. intermenstruelle pain accompanying ovulation, occurring during the period between the menses, usually about midway. labor p’s d. de l’accouchement the rhythmic pains of increasing severity and frequency due to contraction of the uterus at childbirth. phantom limb p. d. fantôme pain felt as though arising in an absent (amputated) limb. psychogenic p. d. psychogène symptoms of physical pain having psychological origin. referred p. d. référée pain felt in a part other than that in which the cause that produced it is situated. rest p. d. de décubitus a continuous burning pain due to ischemia of the lower leg, which begins or is aggravated after reclining and is relieved by sitting or standing.

paint peinture 1. a liquid designed for application to a surface, as of the body or a tooth. 2. badigeonner to apply a liquid to a specific area as a remedial or protective measure.

pair paire 1. a combination of two related, similar, or identical entities or objects. 2. in cardiology, two successive premature beats, particularly two ventricular premature complexes. base p. p. de bases a pair of hydrogenbonded bases, a pyrimidine with a purine base, that bind together two strands, or two parts of a strand, of nucleic acid.

palae(o)- palae(o)- see pale(o)-.

palate palais roof of the mouth; the partition separating the nasal and oral cavities. Adj.: palatal, palatine. cleft p. palatoschisis congenital fissure of median line of palate. hard p. p. dur the anterior portion of the palate, separating the oral and nasal cavities, consisting of the bony framework and covering membranes. soft p. voile du p. the fleshy part of the palate, extending from the posterior edge of the hard palate; the uvula projects from its free inferior border.

palatitis palatite inflammation of the palate.

palat(o)- palat(o)- word element [L.]. palate.

palatoglossal palatoglosse pertaining to the palate and tongue.

palatognathous atteint d’un bec de lièvre having a cleft palate.

palatopharyngeal palatopharyngien pertaining to the palate and pharynx.

palatoplasty palatoplastie plastic reconstruction of the palate.

palatoplegia palatoplégie paralysis of the palate.

palatorrhaphy palatorraphie surgical correction of a cleft palate.

palatum palatum pl. palata [L.] palate.

pale(o)- palé(o)- word element [Gr.]. old. Also palae(o)-.

paleocerebellum paléocervelet, paléocérébellum the phylogenetically second oldest part of the cerebellum, namely the vermis of the anterior lobe and the pyramis, uvula, and paraflocculus of the posterior lobe. Because this corresponds roughly to the primary site of termination of the major spinocerebellar afferents, the term is sometimes equated with spinocerebellum. Spelled also palaeocerebellum. Adj.: paleocerebellar.

paleocortex paléocortex [paleo- + cortex] that portion of the cerebral cortex that, with the archicortex, develops in association with the olfactory system and is phylogenetically older and less stratified than the neocortex. It is composed chiefly of the piriform cortex and the parahippocampal gyrus. Spelled also palaeocortex. Adj.: paleocortical.

paleopathology paléopathologie study of disease in bodies which have been preserved from ancient times.

paleostriatum paléostriatum the phylogenetically older portion of the corpus striatum, represented by the globus pallidus. Adj.: paleostriatal.

pali- pali- word element [Gr.]. again; pathologic repetition. Also palin-.

palin- palin- see pali-.

palindromia récidive [Gr.] a recurrence or relapse. Adj.: palindromic.

palinopsia palinopsie visual perseveration; the continuance of a visual sensation after the stimulus is gone.

palivizumab palivizumab a monoclonal antibody against respiratory syncytial virus (RSV); used as a passive immunizing agent in susceptible infants and children.

palladium (Pd) palladium chemical element (see Table of Elements), at. no. 46; used in alloys for dental and orthodontic appliances.

pallanesthesia pallanesthésie loss or absence of pallesthesia.

pallesthesia pallesthésie the ability to feel mechanical vibrations on or near the body, such as when a vibrating tuning fork is placed over a bony prominence. Adj.: pallesthetic.

palliative palliatif affording relief; also, a drug that so acts.

pallidectomy pallidectomie extirpation of the globus pallidus.

pallidoansotomy pallidoansotomie production of lesions in the globus pallidus and ansa lenticularis.

pallidotomy pallidotomie a stereotaxic surgical technique for the production of lesions in the globus pallidus for treatment of extrapyramidal disorders.

pallidum pallidum globus pallidus. Adj.: pallidal.

pallium pallium [L.] 1. cerebral cortex. 2. the cerebral cortex during its period of development. Adj.: pallial.

pallor pâleur paleness, as of the skin.

palm paume the hollow or flexor surface of the hand. Adj.: palmar.

palma palma pl. palmae [L.] palm.

palmaris palmaris palmar.

palmate palmé having a shape resembling that of a hand with the fingers spread.

palmitic acid acide palmitique a 16-carbon saturated fatty acid found in most fats and oils, particularly associated with stearic acid; one of the most prevalent saturated fatty acids in body lipids.

palmitin palmitine glyceryl tripalmitate; a crystallizable and saponifiable fat from various fats and oils.

palmitoleate palmitoléate a salt (soap), ester, or anionic form of palmitoleic acid.

palmitoleic acid acide palmitoléique a monounsaturated 16-carbon fatty acid occurring in many oils, particularly those derived from marine animals.

palpation palpation the act of feeling with the hand; the application of the fingers with light pressure to the surface of the body for the purpose of determining the condition of the parts beneath in physical diagnosis. Adj.: palpatory.

palpebra paupière pl. palpebrae [L.] eyelid. Adj.: palpebral.

palpebritis palpébrite blepharitis.

palpitation palpitation a subjective sensation of an unduly rapid or irregular heartbeat.

palsy paralysie paralysis. Bell p. p. de Bell unilateral facial paralysis of sudden onset due to a lesion of the facial nerve, resulting in characteristic facial distortion. cerebral p. p. cérébrale any of a group of persisting qualitative motor disorders appearing in young children, resulting from brain damage caused by birth trauma or intrauterine pathology. Erb p., Erb-Duchenne p. p. d’Erb Erb-Duchenne paralysis. facial p. p. faciale Bell p. progressive bulbar p. p. bulbaire progressive chronic, progressive, generally fatal paralysis and atrophy of the muscles of the lips, tongue, mouth, pharynx, and larynx due to lesions of the motor nuclei of the lower brain stem, usually occurring in late adult years. pseudobulbar p. p. pseudobulbaire spastic weakness of the muscles innervated by the cranial nerves, i.e., the facial muscles, pharynx, and tongue, due to bilateral lesions of the corticospinal tract, often accompanied by uncontrolled weeping or laughing. wasting p. p. cachectisante spinal muscular atrophy.

pamabrom pamabrom a mild diuretic used in preparations for the relief of premenstrual symptoms.

pamidronate pamidronate an inhibitor of bone resorption used to treat malignancy-associated hypercalcemia, osteitis deformans, and osteolytic metastasis secondary to breast cancer or myeloma; used as the disodium salt. Complexed with technetium 99 m, it is used in bone imaging.

pampiniform pampiniforme shaped like a tendril.

PAN PAN polyarteritis nodosa.

pan- pan- word element [Gr.]. all.

panagglutinin panagglutinine an agglutinin which agglutinates the erythrocytes of all human blood groups.

panarteritis panartérite polyarteritis.

panatrophy panatrophie atrophy of several parts; diffuse atrophy.

panautonomic qui a trait à l’ensemble du système nerveux autonome pertaining to or affecting the entire autonomic (sympathetic and parasympathetic) nervous system.

pancarditis pancardite diffuse inflammation of the heart.

panchakarma panchakarma [Sanskrit] a fivefold purification treatment used in ayurveda, usually including a purgative to eliminate kapha, a laxative to eliminate pitta, an enema to eliminate vata, inhalation treatment to clear doshas from the head, and bloodletting to purify the blood.

pancolectomy pancolectomie excision of the entire colon, with creation of an ileostomy.

pancreas pancréas pl. pancreata [Gr.] a large, elongated, racemose gland lying transversely behind the stomach, between the spleen and duodenum. Its external secretion contains digestive enzymes. One internal secretion, insulin, is produced by the beta cells, and another, glucagon, is produced by the alpha cells. The alpha, beta, and delta cells form aggregates, called islands of Langerhans. See Plate 27. endocrine p. p. endocrine that part of the pancreas that acts as an endocrine gland, consisting of the islets of Langerhans, which secrete insulin and other hormones. exocrine p. p. exocrine that part of the pancreas that acts as an exocrine gland, consisting of the pancreatic acini, which produce pancreatic juice and secrete it into the duodenum to aid in protein digestion.

pancreatectomy pancréatectomie excision of the pancreas.

pancreatic pancréatique pertaining to the pancreas.

pancreatic elastase élastase pancréatique an endopeptidase catalyzing the cleavage of specific peptide bonds in protein digestion; it is activated in the duodenum by trypsin-induced cleavage of its inactive precursor proelastase. In humans the form expressed is p. e. II.

pancreatic(o)- pancréatic(o)- word element [Gr.]. pancreas; pancreatic duct.

pancreaticoduodenal pancréaticoduodénal pertaining to the pancreas and duodenum.

pancreaticoduodenostomy pancréaticoduodénostomie pancreaticoenterostomy with the duct or pancreas anastomosed to the duodenum.

pancreaticoenterostomy pancréaticoentérostomie anastomosis of the pancreatic duct to the intestine.

pancreaticogastrostomy pancréaticogastrostomie anastomosis of the pancreatic duct to the stomach.

pancreaticojejunostomy pancréaticojéjunostomie pancreaticoenterostomy with the duct or pancreas anastomosed to the jejunum.

pancreatin pancréatine a substance from the pancreas of the hog or ox containing enzymes, principally amylase, protease, and lipase; used as a digestive aid.

pancreatitis pancréatite inflammation of the pancreas. acute hemorrhagic p. p. hémorragique aiguë a condition due to autolysis of pancreatic tissue caused by escape of enzymes into the substance, resulting in hemorrhage into the parenchyma and surrounding tissues.

pancreat(o)- pancréat(o)- word element [Gr.]. pancreas.

pancreatoduodenectomy pancréatoduodénectomie excision of the head of the pancreas along with the encircling loop of the duodenum.

pancreatogenic pancréatogène arising in the pancreas.

pancreatography pancréatographie radiography of the pancreas.

pancreatolithectomy pancréatolithectomie excision of a calculus from the pancreas.

pancreatolithiasis pancréatolithiase presence of calculi in the ductal system or parenchyma of the pancreas.

pancreatolithotomy pancréatolithotomie incision of the pancreas for the removal of calculi.

pancreatolysis pancréatolyse destruction of pancreatic tissue. Adj.: pancreatolytic.

pancreatotomy pancréatotomie incision of the pancreas.

pancreatotropic pancréatotrope having an affinity for the pancreas.

pancrelipase pancrélipase a preparation of hog pancreas containing enzymes, principally lipase with amylase and protease; used as a digestive aid in pancreatic insufficiency.

pancreozymin pancréozymine cholecystokinin.

pancuronium pancuronium a neuromuscular blocking agent used as the bromide salt as an adjunct to anesthesia.

pancystitis pancystite cystitis involving the entire thickness of the wall of the urinary bladder, as occurs in interstitial cystitis.

pancytopenia pancytopénie abnormal depression of all the cellular elements of the blood.

pandemic 1. pandémie a widespread epidemic of a disease. 2. pandémique widely epidemic.

panencephalitis panencéphalite encephalitis, probably of viral origin, which produces intranuclear or intracytoplasmic inclusion bodies that result in parenchymatous lesions of both the gray and white matter of the brain.

panendoscope panendoscope 1. an endoscope that permits wide-angle viewing. 2. a cystoscope that permits wide-angle viewing of the bladder and urethra.

panhypopituitarism panhypopituitarisme generalized hypopituitarism due to absence or damage of the pituitary gland, which, in its complete form, leads to absence of gonadal function and insufficiency of thyroid and adrenal function. When cachexia is a prominent feature, it is called Simmonds disease or pituitary cachexia.

panhysterosalpingectomy hystérosalpingectomie totale excision of the body of the uterus, cervix, and uterine tubes.

panhysterosalpingo-oophorectomy panhystérosalpingo-oophorectomie excision of the uterus, cervix, uterine tubes, and ovaries.

panic panique acute, extreme, and unreasoning fear and anxiety. homosexual p. p. homosexuelle an acute, extreme anxiety reaction brought on by circumstances that induce the unconscious fear of being homosexual or of succumbing to homosexual impulses.

panmyelophthisis panmyélophtisie aplastic anemia.

panniculectomy panniculectomie surgical excision of the abdominal apron of superficial fat in the obese.

panniculitis panniculite inflammation of the panniculus adiposus, especially of the abdomen. lobular p. p. lobulaire any of the types affecting mainly the lobules of adipose tissue, often with necrosis or other types of degeneration. nodular nonsuppurative p., relapsing febrile nodular nonsuppurative p. p. nodulaire non suppurative a type of predominantly lobular panniculitis of the lower legs, with fever and formation of tender nodules. septal p. p. septale any of the types affecting mainly the septa between the lobules of adipose tissue, usually with formation of nodules.

panniculus pannicule pl. panniculi [L.] a layer of membrane. p. adiposus p. adipeux the subcutaneous fat: a layer of fat underlying the dermis.

pannus pannus [L.] 1. superficial vascularization of the cornea with infiltration of granulation tissue. 2. an inflammatory exudate overlying the synovial cells on the inside of a joint. 3. panniculus adiposus. p. trachomatosus p. de la cornée pannus of the cornea secondary to trachoma.

panophthalmitis panophtalmie inflammation of all the eye structures or tissues.

panotitis panotite inflammation of all the parts or structures of the ear.

panphobia panphobie fear of everything; vague and persistent dread of an unknown evil.

panretinal panrétinien pertaining to or encompassing the entire retina.

Panstrongylus Panstrongylus a genus of hemipterous insects, species of which transmit trypanosomes.

pansystolic pansystolique pertaining to or affecting all of, or occurring throughout, systole.

pantetheine pantothéine an amide of pantothenic acid, an intermediate in the biosynthesis of CoA, a growth factor for Lactobacillus bulgaricus, and a cofactor in certain enzyme complexes.

pant(o)- pant(o)- word element [Gr.]. all; the whole.

Pantoea Pantoea a widely distributed genus of gram-negative, usually motile, rod-shaped bacteria, including P. agglomerans, which causes nosocomial infections.

pantoprazole pantoprazole a gastric acid pump inhibitor similar to omeprazole, used as the sodium salt in the treatment of erosive esophagitis associated with gastroesophageal reflux disease and of pathological hypersecretion associated with Zollinger-Ellison syndrome or other neoplastic cindition.

pantothenate pantothénate any salt of pantothenic acid; calcium p. is used as a dietary source of pantothenic acid.

pantothenic acid acide panthoténique a component of coenzyme A and a member of the vitamin B complex; necessary for nutrition in some animal species, but of uncertain importance for humans.

pantropic pantrope having an affinity for or affecting many tissues or cells.

papain papaïne a proteolytic enzyme from the latex of papaw, Carica papaya, which catalyzes the hydrolysis of proteins and polypeptides to amino acids; used as a protein digestant and as a topical application for enzymatic débridement.

papaverine papavérine a smooth muscle relaxant and vasodilator used as the hydrochloride salt to relieve arterial spasms causing cerebral, peripheral, or myocardial ischemia and also injected into the penis in the diagnosis and treatment of erectile dysfunction.

paper papier a material manufactured in thin sheets from fibrous substances that have first been reduced to a pulp. litmus p. p. de tournesol moisture-absorbing paper impregnated with a solution of litmus: if slightly acid, it is red, and alkalis turn it blue; if slightly alkaline, it is blue and acid turns it red. test p. p. réactif paper stained with a compound that changes visibly on occurrence of a chemical reaction.

papilla papille pl. papillae [L.] a small nippleshaped projection or elevation. circumvallate papillae p. caliciformes vallate papillae. conical papillae p. coniques sparsely scattered elevations on the tongue, often considered to be modified filiform papillae. dental p., dentinal p. p. dentaire a small mass of condensed mesenchyme in the enamel organ; it differentiates into the dentin and dental pulp. dermal p. p. dermique any of the conical extensions of the fibers, capillary blood vessels, and sometimes nerves of the dermis into corresponding spaces among downward- or inward-projecting rete ridges on the undersurface of the epidermis. duodenal p. p. duodénale either of two small elevations on the mucosa of the duodenum, the major at the entrance of the conjoined pancreatic and common bile ducts and the minor at the entrance of the accessory pancreatic duct. filiform papillae p. filiforme threadlike elevations covering most of the tongue surface. foliate papillae p. foliée parallel mucosal folds on the tongue margin at the junction of its body and root. fungiform papillae p. fongiforme knoblike projections of the tongue scattered among the filiform papillae. gingival p. p. gingivale the cone-shaped pad of gingiva filling the space between the teeth up to the contact area. hair p. p. pileuse a fibrovascular dermal papilla enclosed within the hair bulb. ileal p., ileocecal p. p. iléale the conical projection formed by the terminal ileum at its junction with the cecum, corresponding to the ileocecal valve in the cadaver. incisive p. p. incisive an elevation at the anterior end of the raphe of the palate. interdental p. p. interdentaire gingival p. lacrimal p. p. lacrymale one in the conjunctiva near the medial angle of the eye. lingual papillae p. linguales see conical, filiform, foliate, fungiform, and vallate papillae. mammary p. p. mammaire nipple (1). optic p. p. optique optic disk. palatine p. p. palatine incisive p. renal papillae p. rénales the blunted apices of the renal pyramids. vallate papillae V lingual eight to twelve large papillae arranged in a V near the base of the tongue.

papillary papillaire pertaining to or resembling a papilla, or nipple.

papilledema œdème papillaire edema of the optic disk.

papillitis papillite 1. inflammation of a papilla. 2. a form of optic neuritis involving the optic papilla (disk).

papilloma papillome a benign tumor derived from epithelium. Adj.: papillomatous. fibroepithelial p. p. fibroépithélial a type containing extensive fibrous tissue. intracanalicular p. p. intracanaliculaire an arborizing nonmalignant growth within the ducts of certain glands, particularly of the breast. intraductal p. p. intracanalaire a tumor in a lactiferous duct, usually attached to the wall by a stalk; it may be solitary, often with a serous or bloody nipple discharge, or multiple. inverted p. p. inversé one in which the proliferating epithelial cells invaginate into the underlying stroma.

papillomatosis papillomatose development of multiple papillomas.

Papillomavirinae Papillomavirinae the papillomaviruses; a subfamily of viruses (family Papovaviridae) that induce papillomas in susceptible hosts; the single genus is Papillomavirus.

Papillomavirus Papillomavirus papillomaviruses; a genus of viruses (subfamily Papillomavirinae) that induce papillomas in humans and other animals; some have been associated with malignancy.

papillomavirus papillomavirus any virus of the subfamily Papillomavirinae. human p. (HPV) p. humain any of a number of species that cause warts, particularly plantar warts and genital warts, on the skin and mucous membranes in humans; some are associated with malignancies of the genital tract.

papilloretinitis papillorétinite inflammation of the optic disk and retina.

papillotomy papillotomie incision of a papilla, as of a duodenal papilla.

Papovaviridae Papovaviridae the papovaviruses: a family of DNA viruses, many of which are oncogenic or potentially oncogenic; it includes two subfamilies, Papillomavirinae and Polyomavirinae.

papovavirus papovavirus any virus of the family Papovaviridae. lymphotropic p. (LPV) p. lymphotrope a polyomavirus originally isolated from a B-lymphoblastic cell line of an African green monkey; antigenically related viruses are widespread in primates and may infect humans.

papulation papulation the formation of papules.

papule papule a small, circumscribed, solid, elevated lesion of the skin. Adj.: papular. piezogenic p’s p. piézogéniques soft, sometimes painful, large papules above the heel on the side of one or both feet, caused by weight bearing associated with prolonged standing or running.

papulonecrotic papulonécrotique characterized by both papules and necrosis.

papulosis papulose the presence of multiple papules. bowenoid p. p. bowénoïde benign reddish brown papules, usually on the genitalia, particularly the penis, in young adults; believed to have a viral etiology.

papyraceous papyracé like paper.

para pare a woman who has produced one or more viable offspring, regardless of whether the child or children were living at birth. Used with Roman numerals to designate the number of such pregnancies, as para 0 (none— nullipara), para I (one—primipara), para II (two— secundipara), etc. Symbol P.

para- para- 1. word element [Gr.]. beside; near; resembling; accessory to; beyond; apart from; abnormal. 2. symbol p-. In organic chemistry, indicating a substituted benzene ring whose substituents are on opposite carbon atoms in the ring.

para-aminobenzoic acid acide para- aminobenzoïque p-aminobenzoic acid.

para-aminohippuric acid acide para- aminohippurique p-aminohippuric acid.

para-aminosalicylic acid acide para- aminosalicylique p-aminosalicylic acid.

para-anesthesia para-anesthésie anesthesia of the lower part of the body.

para-aortic para-aortique near or next to the aorta.

parabiosis parabiose the union of two individuals, as conjoined twins, or of experimental animals by surgical operation. Adj.: parabiotic.

paracasein paracaséine the chemical product of the action of rennin on casein.

paracentesis paracentèse surgical puncture of a cavity for the aspiration of fluid. Adj.: paracentetic.

paracentral paracentral near a center.

paracervical paracervical near a neck or cervix, particularly the uterine cervix.

Parachlamydia Parachlamydia a genus of gram-variable coccoid bacteria of the family Parachlamydiaceae that are naturally parasites of free-living amebae and cause respiratory infections in humans.

Parachlamydiaceae Parachlamydiaceae a family of bacteria of the order Chlamydiales that are natural parasites of free-living amebae.

paracholera paracholéra a disease resembling Asiatic cholera but not caused by Vibrio cholerae.

parachordal parachordal situated beside the notochord.

paraclinical paraclinique pertaining to abnormalities (e.g., morphological or biochemical) underlying clinical manifestations (e.g., chest pain or fever).

paracoccidioidal paracoccidioïdien pertaining to or caused by fungi of the genus Paracoccidioides.

Paracoccidioides Paracoccidioides a genus of Fungi Imperfecti of the family Moniliaceae; they proliferate by multiple budding yeast cells in the tissues. P. brasiliensis is the etiologic agent of paracoccidioidomycosis.

paracoccidioidomycosis paracoccidioïdomycose an often fatal, chronic granulomatous disease caused by Paracoccidioides brasiliensis, primarily involving the lungs, but spreading to the skin, mucous membranes, lymph nodes, and internal organs.

paracrine paracrine 1. denoting a type of hormone function in which hormone synthesized in and released from endocrine cells binds to its receptor in nearby cells and affects their function. 2. denoting the secretion of a hormone by an organ other than an endocrine gland.

paracusia paracousie 1. any deficiency in the sense of hearing. 2. auditory hallucination.

paracusis paracousie paracusia.

paradidymis paradidyme a group of several convoluted tubules in the anterior part of the spermatic cord; probably a remnant of the mesonephros.

paradox paradoxe a seemingly contradictory occurrence. Adj.: paradoxic, paradoxical. Weber p. p. de Weber elongation of a muscle that has been so stretched that it cannot contract.

paraduodenal paraduodénal alongside, near, or around the duodenum.

paraesophageal parœsophagien near or beside the esophagus.

paraffin paraffine 1. a purified hydrocarbon wax used for embedding histological specimens and as a stiffening agent in pharmaceutical preparations. 2. alkane. liquid p. p. liquide mineral oil.

paraffinoma paraffinome a chronic granuloma produced by prolonged exposure to paraffin.

paraflocculus paraflocculus a small lobe of the cerebellar hemisphere, immediately cranial to the flocculus.

paraganglioma paragangliome a tumor of the tissue composing the paraganglia. nonchromaffin p. p. non chromaffine chemodectoma.

paraganglion paraganglion pl. paraganglia a collection of chromaffin cells derived from neural ectoderm, occurring outside the adrenal medulla, usually near the sympathetic ganglia and in relation to the aorta and its branches.

parageusia paragueusie 1. perversion of the sense of taste. 2. a bad taste in the mouth.

paragonimiasis paragonimose infection with flukes of the genus Paragonimus.

Paragonimus Paragonimus a genus of parasitic flukes that have two invertebrate hosts, the first a snail, the second a crab or crayfish. P. westermani is the lung fluke of southern and eastern Asia, found in cysts in the lungs and sometimes elsewhere in humans and other animals that have eaten infected freshwater crayfish and crabs.

paragranuloma paragranulome the most benign form of Hodgkin disease, largely confined to the lymph nodes.

parahemophilia parahémophilie a hereditary hemorrhagic tendency due to deficiency of coagulation factor V.

parahippocampal para-hippocampique, para-hippocampal near or next to the hippocampus.

parahormone parahormone a substance, not a true hormone, which has a hormone-like action in controlling the functioning of some distant organ.

parainfectious para-infectieux pertaining to manifestations of infectious disease that are caused by the immune response to the infectious agent.

parakeratosis parakératose persistence of the nuclei of keratinocytes as they rise into the stratum corneum of the epidermis. It is normal in the epithelium of the true mucous membrane of the mouth and vagina.

parakinesia parakinésie perversion of motor function; in ophthalmology, irregular action of an individual ocular muscle.

paralalia paralalie a disorder of speech, especially the production of a vocal sound different from the one desired.

parallagma parallagme displacement of a bone or of the fragments of a broken bone.

parallergy parallergie a condition in which an allergic state, produced by specific sensitization, predisposes the body to react to other allergens with clinical manifestations that differ from the original reaction. Adj.: parallergic.

paralysis paralysie pl. paralyses loss or impairment of motor function in a part due to lesion of the neural or muscular mechanism; also, by analogy, impairment of sensory function (sensory p.). p. of accommodation p. de l’accommodation paralysis of the ciliary muscles so as to prevent accommodation of the eye. p. agitans p. agitante Parkinson disease. ascending p. p. ascendante spinal paralysis that progresses cephalad. brachial p. p. brachiale paralysis of an upper limb from a lesion of the brachial plexus. bulbar p. p. bulbaire progressive bulbar palsy. central p. p. centrale any paralysis due to a lesion of the brain or spinal cord. compression p. p. par compression that caused by pressure on a nerve. conjugate p. p. conjuguée loss of ability to perform some parallel ocular movements. crossed p., cruciate p. p. croisée that affecting one side of the face and the other side of the body. crutch p. p. des béquillards compression paralysis of one or both of the upper limbs because of pressure of the crutch in the axilla. decubitus p. p. en décubitus that due to pressure on a nerve from lying for a long time in one position. divers’ p. p. du plongeur decompression sickness. Duchenne p. p. de Duchenne 1. Erb-Duchenne p. 2. progressive bulbar palsy. Erb-Duchenne p. syndrome de Duchenne-Erb paralysis of the upper roots of the brachial plexus, caused by birth injury. facial p. p. faciale weakening or paralysis of the facial nerve, as in Bell palsy. familial periodic p. p. périodique familiale a rare inherited disorder with recurring attacks of rapidly progressive flaccid paralysis associated with serum potassium levels that are decreased (type I or hypokalemic type), increased (type II or hyperkalemic type), or normal (type III or normokalemic type). flaccid p. p. flasque any paralysis accompanied by loss of muscle tone and absence of tendon reflexes in the paralyzed part. hyperkalemic periodic p. p. périodique hyperkaliémique see familial periodic p. hypokalemic periodic p. p. périodique hypokaliémique see familial periodic p. hysterical p. p. hystérique paralysis in a part owing to a conversion disorder, without any organic neurological cause. juvenile p. agitans p. agitante juvénile increased muscle tonus with the characteristic attitude and facies of paralysis agitans, occurring in infants because of progressive degeneration of the globus pallidus. Klumpke p., Klumpke-Dejerine p. p. de Klumpke lower brachial plexus paralysis caused by birth injury, particularly during a breech delivery. Landry p. p. de Landry acute idiopathic polyneuritis. mixed p. p. mixte combined motor and sensory paralysis. motor p. p. motrice paralysis of voluntary muscles. musculospiral p. p. musculospirale paralysis of the extensor muscles of the wrist and fingers. normokalemic periodic p. p. périodique normokaliémique see familial periodic p. obstetric p. p. obstétrique paralysis caused by injury received at birth. periodic p. p. périodique 1. any of various diseases characterized by episodic flaccid paralysis or muscular weakness. 2. familial periodic p. postepileptic p. p. postépileptique Todd p. progressive bulbar p. p. bulbaire progressive see under palsy. sensory p. p. sensorielle loss of sensation due to a morbid process. sleep p. p. du sommeil paralysis upon awakening or sleep onset because of extension of the atonia of REM sleep into the waking state, often seen in those suffering from narcolepsy or sleep apnea. spastic p. p. spastique paralysis marked by spasticity of the muscles of the paralyzed part and increased tendon reflexes, due to upper motor neuron lesions. thyrotoxic periodic p. p. périodique thyrotoxique recurrent episodes of generalized or local paralysis accompanied by hypokalemia, occurring in association with Graves disease, especially after exercise or a high carbohydrate or high sodium meal. tick p. p. à tiques a progressive ascending type of flaccid paralysis seen in children and domestic animals following the bite of certain ticks, usually the result of toxins from the tick’s saliva that enter the central nervous system of the host. Todd p. p. de Todd transient hemiplegia or monoplegia after an epileptic seizure. vasomotor p. p. vasomotrice cessation of vasomotor control.

paralytic paralytique 1. affected with or pertaining to paralysis. 2. a person affected with paralysis.

paralyzant paralysant 1. causing paralysis. 2. a drug that causes paralysis.

paramagnetic paramagnétique being attracted by a magnet and assuming a position parallel to that of a magnetic force, but not becoming permanently magnetized.

paramastitis paramastite inflammation of tissues around the mammary gland.

Paramecium Paramecium a genus of ciliate protozoa.

paramecium paramécie pl. paramecia an organism of the genus Paramecium.

parameter paramètre 1. a constant that distinguishes specific cases, having a definite fixed value in one case but different values in other cases. 2. in statistics, a value that specifies one of the members of a family of probability distributions, such as the mean or standard deviation. 3. a variable whose measure is indicative of a quantity or function that cannot itself be directly determined precisely.

parametric paramétrique situated near the uterus; parametrial.

parametric paramétrique pertaining to or defined in terms of a parameter.

parametritis paramétrite inflammation of the parametrium.

parametrium paramètre the extension of the subserous coat of the supracervical portion of the uterus laterally between the layers of the broad ligament. Adj.: parametrial.

paramnesia paramnésie a disturbance of memory in which reality and fantasy are confused.

Paramoeba Paramoeba a genus of parasitic or free-living ameboid protozoa.

paramyloidosis paramyloïdose accumulation of an atypical form of amyloid in tissues.

paramyoclonus paramyoclonie myoclonus in several unrelated muscles. p. multiplex paramyoclonus multiplex a form of myoclonus of unknown etiology starting in the muscles of the upper arms and shoulders and spreading to other parts of the upper body.

paramyotonia paramyotonie a disease marked by tonic spasms due to disorder of muscular tonicity, especially a hereditary and congenital affection. p. congenita p. congénitale an inherited disorder similar to myotonia congenita, except that the precipitating factor is cold exposure, the myotonia is aggravated by activity, and only the proximal muscles of the limbs, eyelids, and tongue are affected.

Paramyxoviridae Paramyxoviridae the paramyxoviruses; a family of RNA viruses with a single-stranded, negative-sense RNA genome, including two subfamilies, Paramyxovirinae and Pneumovirinae.

Paramyxovirinae Paramyxovirinae a subfamily of the family Paramyxoviridae, containing three genera: Morbillivirus, Paramyxovirus, and Rubulavirus.

Paramyxovirus Paramyxovirus 1. a genus of viruses (family Paramyxoviridae) that cause chiefly respiratory infections in a variety of vertebrate hosts; included are mumps and parainfluenza viruses. 2. paramyxoviruses; a genus of viruses of the subfamily Paramyxovirinae (family Paramyxoviridae) that cause chiefly respiratory infections in a variety of vertebrate hosts.

paramyxovirus paramyxovirus any virus of the family Paramyxoviridae.

paranasal paranasal alongside or near the nose.

paraneoplastic paranéoplasique pertaining to changes produced in tissue remote from a tumor or its metastases.

paranephric paranéphrique near the kidney.

paranephritis paranéphrite 1. inflammation of the adrenal gland. 2. inflammation of the connective tissue around the kidney.

paranesthesia paranesthésie para-anesthesia.

paranoia paranoïa 1. behavior characterized by well-systematized delusions of grandeur or persecution or a combination. 2. former name for delusional disorder. Adj.: paranoiac, paranoid.

paranomia paranomie amnestic aphasia.

paraoral paraoral 1. near or adjacent to the mouth. 2. administered by some route other than by the mouth; said of medication.

paraparesis paraparésie partial paralysis of the lower limbs. tropical spastic p. p. tropicale spastique chronic progressive myelopathy.

parapertussis paracoqueluche an acute respiratory disease clinically indistinguishable from mild or moderate pertussis, caused by Bordetella parapertussis.

paraphasia paraphasie partial aphasia in which the patient employs wrong words, or uses words in wrong and senseless combinations (choreic p.).

paraphia paraphie perversion of the sense of touch.

paraphilia paraphilie a psychosexual disorder marked by sexual urges, fantasies, and behavior involving objects, suffering or humiliation, or children or other nonconsenting partners. Adj.: paraphiliac.

paraphimosis paraphimosis retraction of phimotic foreskin, causing a painful swelling of the glans, sometimes progressing to dry gangrene.

paraplectic paraplectique paraplegic.

paraplegia paraplégie paralysis of the lower part of the body, including the legs.

paraplegic paraplégique 1. pertaining to or of the nature of paraplegia. 2. an individual with paraplegia.

Parapoxvirus Parapoxvirus parapoxviruses; a genus of viruses comprising viruses of ungulates, including those causing orf and paravaccinia.

parapraxis parapraxie pl. parapraxes a faulty action, as a slip of the tongue or misplacement of an object, which in psychoanalytic theory is due to unconscious associations and motives.

paraprotein paraprotéine a normal or abnormal plasma protein appearing in large quantities as a result of a pathological condition; term now largely replaced by M component.

paraproteinemia paraprotéinémie plasma cell dyscrasia.

parapsoriasis parapsoriasis any of a group of slowly developing, persistent, maculopapular scaly erythrodermas, without subjective symptoms and resistant to treatment.

paraquat paraquat a poisonous compound, some of whose salts are used as contact herbicides. Contact with concentrated solutions causes irritation of the skin, cracking and shedding of the nails, and delayed healing of cuts and wounds. After ingestion of large doses, renal and hepatic failure may develop, followed by pulmonary insufficiency.

pararosaniline pararosaniline a basic dye; a triphenylmethane derivative, one of the components of basic fuchsin.

pararrhythmia pararythmie parasystole.

parasacral parasacral beside or near the sacrum.

parasexual parasexuel accomplished by other than sexual means, as by genetic study of in vitro somatic cell hybrids.

parasinoidal parasinoïdal situated along the course of a sinus.

parasite parasite 1. a plant or animal that lives upon or within another living organism at whose expense it obtains some advantage; see symbiosis. 2. the smaller, less complete member of asymmetrical conjoined twins, attached to and dependent upon the autosite. Adj.: parasitic. malarial p. p. malarique Plasmodium. obligatory p. p. obligatoire one that is entirely dependent on a host for its survival.

parasitemia parasitémie the presence of parasites, especially malarial forms, in the blood.

parasitism parasitisme 1. symbiosis in which one population (or individual) adversely affects another, but cannot live without it. 2. infection or infestation with parasites.

parasitogenic parasitogénique due to parasites.

parasitology parasitologie the scientific study of parasites and parasitism.

parasitotropic parasitotrope having an affinity for parasites.

parasomnia parasomnie a category of sleep disorders in which abnormal events occur during sleep, such as sleepwalking or talking; due to inappropriately timed activation of physiological systems.

paraspadias paraspadias a congenital condition in which the urethra opens on one side of the penis.

parasternal parasternal situated beside the sternum.

parasuicide parasuicide attempted suicide, emphasizing that in most such attempts death is not the desired outcome.

parasympathetic parasympathique see under system.

parasympatholytic parasympatholytique anticholinergic.

parasympathomimetic parasympathomimétique cholinergic.

parasystole parasystole a cardiac irregularity attributed to the interaction of two foci independently initiating cardiac impulses at different rates.

paratenon paraténon the fatty areolar tissue filling the interstices of the fascial compartment in which a tendon is situated.

parathion parathion a highly toxic agricultural insecticide.

parathormone parathormone parathyroid hormone.

parathymia parathymie a perverted, contrary, or inappropriate mood.

parathyroid 1. parathyroïdien situated beside the thyroid gland. 2. parathyroïde see under gland.

parathyroprival parathyréoprive hypoparathyroid.

parathyrotropic parathyréotrope having an affinity for the parathyroid glands.

paratope paratope the site on the antibody molecule that attaches to an antigen.

paratuberculosis paratuberculose a tuberculosis-like disease not due to Mycobacterium tuberculosis.

paratyphoid paratyphoïde infection due to Salmonella of all groups except S. typhi.

paraurethral para-urétral near the urethra.

paravaccinia paravaccine an infection due to the paravaccinia virus, producing papular, and later vesicular, pustular, and scabular, lesions on the udders and teats of milk cows, the oral mucosa of suckling calves, and the hands of humans milking infected cows.

paravaginitis paravaginite inflammation of the tissues alongside the vagina.

paravertebral paravertébral beside the vertebral column.

paravesical paravésical perivesical.

parazone parazone one of the white bands alternating with dark bands (diazones) seen in cross section of a tooth.

parenchyma parenchyme [Gr.] the essential or functional elements of an organ, as distinguished from its stroma or framework. Adj.: parenchymal, parenchymatous. renal p. p. rénal the functional tissue of the kidney, consisting of the nephrons.

parenteral parentéral not through the alimentary canal, but rather by injection through some other route, as subcutaneous, intramuscular, etc.

paresis parésie slight or incomplete paralysis. general p. p. générale paralytic dementia; a form of neurosyphilis in which chronic meningoencephalitis causes gradual loss of cortical function, progressive dementia, and generalized paralysis.

paresthesia paresthésie morbid or perverted sensation; an abnormal sensation, as burning, prickling, formication, etc.

paretic parétique pertaining to or affected with paresis.

paricalcitol paricalcitol a synthetic vitamin D analogue, used for the prevention and treatment of hyperparathyroidism secondary to chronic renal failure.

paries paroi pl. parietes [L.] a wall, as of an organ or cavity.

parietal pariétal 1. of or pertaining to the walls of a cavity. 2. pertaining to or located near the parietal bone.

parietofrontal pariétofrontal pertaining to the parietal and frontal bones, gyri, or fissures.

parietooccipital pariéto-occipital pertaining to the parietal and occipital bones or lobes.

parity parité 1. para; the condition of a woman with respect to having borne viable offspring. 2. equality; close correspondence or similarity.

parkinsonism parkinsonisme a group of neurological disorders marked by hypokinesia, tremor, and muscular rigidity, including the parkinsonian syndrome and Parkinson disease. Adj.: parkinsonian.

paroccipital paroccipital near the occipital bone.

paromomycin paromomycine a broad- spectrum antibiotic derived from Streptomyces rimosus var. paromomycinus; the sulfate salt is used as an antiamebic.

paronychia paronychie inflammation involving the folds of tissue around the fingernail.

paronychial paronychial pertaining to paronychia or to the nail folds.

paroöphoron paroophore an inconstantly present small group of coiled tubules between the layers of the mesosalpinx, being a remnant of the excretory part of the mesonephros.

parophthalmia parophthalmie inflammation of the connective tissue around the eye.

parosteal parostéal pertaining to the outer surface of the periosteum.

parostosis parostose ossification of tissues outside the periosteum.

parotid parotide 1. near the ear. 2. pertaining to a parotid gland.

parotitis parotite inflammation of the parotid gland. epidemic p., infectious p. p. épidémique 1. parotitis caused by an infectious agent, usually bacteria or viruses. 2. mumps.

parovarian para-ovarien 1. beside the ovary. 2. pertaining to the epoöphoron.

paroxetine paroxetine a selective serotonin uptake inhibitor used as the hydrochloride salt to treat depression and obsessive-compulsive, panic, and social anxiety disorders.

paroxysm paroxysme 1. a sudden recurrence or intensification of symptoms. 2. a spasm or seizure. Adj.: paroxysmal.

pars pars pl. partes [L.] part. p. plana p. plana ciliary disk; the thin part of the ciliary body.

pars planitis pars planitis granulomatous uveitis of the pars plana of the ciliary body.

part partie a division of a larger structure. mastoid p. of temporal bone p. mastoïde de l’os temporal mastoid bone; the irregular, posterior part of the temporal bone. petromastoid p. of temporal bone p. pétromastoïde de l’os temporal see petrous p. of temporal bone. petrous p. of temporal bone p. pétreuse de l’os temporal petrous bone; the part of the temporal bone at the base of the cranium, containing the inner ear. Some divide it into two subparts, calling the posterior section the mastoid part, reserving the term petrous part for the anterior section only, and calling the entire area the petromastoid part. squamous p. of temporal bone p. squameuse de l’os temporal squamous bone; the flat, scalelike, anterior superior portion of the temporal bone. tympanic p. of temporal bone p. tympanique de l’os temporal tympanic bone; the part of the temporal bone forming the anterior and inferior walls and part of the posterior wall of the external acoustic meatus.

particle particule a tiny mass of material. Dane p. p. de Dane an intact hepatitis B viral particle. viral p., virus p. p. virale virion.

partitioning cloisonnement dividing into parts. gastric p. c. gastrique any of various gastroplasty procedures for morbid obesity in which a small stomach pouch is walled off, whose filling signals satiety.

parturient parturiente giving birth or pertaining to birth; by extension, a woman in labor.

parturiometer parturiomètre device used in measuring the expulsive power of the uterus.

parturition parturition childbirth.

parulis parulie a subperiosteal abscess of the gum.

parvicellular parvicellulaire composed of small cells.

Parvoviridae Parvoviridae the parvoviruses: a family of DNA viruses with a linear singlestranded DNA genome, including the genera Parvovirus and Dependovirus.

Parvovirus Parvovirus parvoviruses; a genus of viruses (family Parvoviridae) infecting mammals and birds; human parvoviruses cause aplastic crisis, erythema infectiosum, hydrops fetalis, spontaneous abortion, and fetal death.

parvovirus parvovirus any virus belonging to the family Parvoviridae.

PAS, PASA PAS p-aminosalicylic acid.

pascal (Pa) pascal the SI unit of pressure, which corresponds to a force of one newton per square meter.

passive passif neither spontaneous nor active; not produced by active efforts.

PASSOR PASSOR Physiatric Association of Spine, Sports, and Occupational Rehabilitation.

paste pâte a semisolid preparation containing one or more drug substances, for topical application.

Pasteurella Pasteurella a genus of gram-negative bacteria of the family Pasteurellaceae, including P. multocida, the etiologic agent of the hemorrhagic septicemias.

Pasteurellaceae Pasteurellaceae a family of facultatively anaerobic, nonmotile, gram-negative, coccoid to rod-shaped bacteria of the order Pasteurellales, occurring as parasites in mammals and birds.

Pasteurellales Pasteurellales an order of bacteria of the class Gammaproteobacteria.

pasteurellosis pasteurellose infection with organisms of the genus Pasteurella.

patch 1. tache a small area differing from the rest of a surface. 2. pièce a small piece of cloth or other material that covers part of another surface. 3. plaque a macule more than 1 cm in diameter. Peyer p’s p. de Peyer oval elevated patches of closely packed lymph follicles on the mucosa of the small intestines. salmon p. t. saumonée a common type of pink or skin- colored nevus flammeus seen on the forehead or nape of the neck in neonates. transdermal p. timbre transdermique a drug delivery system in which a patch with medication is placed on the skin so that the medication is gradually absorbed over time.

patella rotule [L.] knee cap; a triangular sesamoid bone situated at the front of the knee in the tendon of insertion of the quadriceps femoris muscle. See Plate 1. Adj.: patellar.

patellectomy patellectomie excision of the patella.

patent 1. patent open, unobstructed, or not closed. 2. manifeste apparent, evident.

pathergy pathergie 1. a condition in which the application of a stimulus leaves the organism unduly susceptible to subsequent stimuli of a different kind. 2. a condition of being allergic to numerous antigens. Adj.: pathergic.

pathfinder orienteur-marqueur 1. an instrument for locating urethral strictures. 2. a dental instrument for tracing the course of root canals.

path(o)- path(o)- word element [Gr.]. disease.

pathoanatomical patho-anatomique pertaining to anatomic pathology.

pathobiology pathobiologie a branch of pathology that focuses on biological aspects such as structural and functional changes of organs.

pathoclisis pathoclise a specific sensitivity to specific toxins, or a specific affinity of certain toxins for certain systems or organs.

pathogen pathogène any disease-producing agent or microorganism. Adj.: pathogenic.

pathogenesis pathogenèse the development of morbid conditions or of disease; more specifically the cellular events and reactions and other pathologic mechanisms occurring in the development of disease. Adj.: pathogenetic.

pathognomonic pathognomonique specifically distinctive or characteristic of a disease or pathologic condition; denoting a sign or symptom on which a diagnosis can be made.

pathologic pathologique 1. indicative of or caused by some morbid condition. 2. pertaining to pathology.

pathological pathologique pathologic.

pathology pathologie 1. the branch of medicine dealing with the essential nature of disease, especially changes in body tissues and organs that cause or are caused by disease. 2. the structural and functional manifestations of disease. anatomic p. anatomopathologie the anatomical study of changes in the function, structure, or appearance of organs or tissues, including postmortem examinations and the study of biopsy specimens. cellular p. p. cellulaire cytopathology. clinical p. p. clinique pathology applied to the solution of clinical problems, especially the use of laboratory methods in clinical diagnosis. comparative p. p. comparative that which considers human disease processes in comparison with those of other animals. oral p. p. orale that treating of conditions causing or resulting from morbid anatomic or functional changes in the structures of the mouth. surgical p. p. chirurgicale the pathology of disease processes that are surgically accessible for diagnosis or treatment.

pathomimesis pathomimie mimicry of a disease or disorder, particularly malingering.

pathomorphism pathomorphisme perverted or abnormal morphology.

pathophysiology pathophysiologie the physiology of disordered function.

pathopsychology pathopsychologie the psychology of mental disease.

pathovar pathovar a variant strain of a bacterial species, differentiated by reactions in one or more hosts.

pathway voie 1. a course usually followed. 2. the nerve structures through which an impulse passes between groups of nerve cells or between the central nervous system and an organ or muscle. 3. metabolic p. accessory conducting p. v. conductrice accessoire myocardial fibers that propagate the atrial contraction impulse to the ventricles but are not a part of the normal atrioventricular conducting system. afferent p. v. afférente the nerve structures through which an impulse, especially a sensory impression, is conducted to the cerebral cortex. alternative complement p. v. alternative du complément a pathway of complement activation initiated by a variety of factors other than those initiating the classical pathway, including IgA immune complexes, bacterial endotoxins, microbial polysaccharides, and cell walls. It does not include factors C1, C2, and C4 of the classical complement pathway but does include factors B and D and properdin. amphibolic p. v. amphibolique a group of metabolic reactions providing small metabolites for further metabolism to end products or for use as precursors in synthetic, anabolic reactions. circus p. v. circulaire a ring or circuit traversed by an abnormal excitatory wavefront, as in reentry. classical complement p. v. classique du complément a pathway of complement activation, comprising nine components (C1 to C9), initiated by antigen-antibody complexes containing immunoglobulins IgG or IgM. common p. of coagulation v. commune de la coagulation the steps in the mechanism of coagulation from the activation of factor X through the conversion of fibrinogen to fibrin. efferent p. v. efférente the nerve structures through which an impulse passes away from the brain, especially for the innervation of muscles, effector organs, or glands. Embden-Meyerhof p. v. d’Embden-Meyerhof the series of enzymatic reactions in the anaerobic conversion of glucose to lactic acid, resulting in energy in the form of adenosine triphosphate (ATP). extrinsic p. of coagulation v. extrinsèque de la coagulation the mechanism that produces fibrin following tissue injury, beginning with formation of an activated complex between tissue factor and factor VII and leading to activation of factor X, inducing the reactions of the common pathway of coagulation. final common p. v. finale commune a motor pathway consisting of the motor neurons by which nerve impulses from many central sources pass to a muscle or gland in the periphery. intrinsic p. of coagulation v. intrinsèque de la coagulation a sequence of reactions leading to fibrin formation, beginning with the contact activation of factor XII, and resulting in the activation of factor X to initiate the common pathway of coagulation. lipoxygenase p. v. de la lipoxygénase a pathway for the formation of leukotrienes and hydroxyeicosatetraenoic acid from arachidonic acid. metabolic p. v. métabolique a series of enzymatic reactions that converts one biological material to another. motor p. v. motrice an efferent pathway conducting impulses from the central nervous system to a muscle. pentose phosphate p. v. du pentose phosphate a major branching of the Embden-Meyerhof pathway of carbohydrate metabolism, successively oxidizing hexoses to form pentose phosphates. reentrant p. v. de réentrée that over which the impulse is conducted in reentry.

-pathy -pathie word element [Gr.]. morbid condition or disease; generally used to designate a noninflammatory condition.

patrilineal patrilinéaire descended through the male line.

patulous ouvert spread widely apart; open; distended.

pauci- pauci- word element [L.]. few. Cf. olig(o)-.

paucisynaptic paucisynaptique oligosynaptic.

pause pause an interruption or rest. compensatory p. p. compensatoire the pause in impulse generation after an extrasystole, either full if the sinus node is not reset or incomplete or noncompensatory if the node is reset and the cycle length is disrupted. sinus p. p. sinusale a transient interruption in the sinus rhythm, of a duration that is not an exact multiple of the normal cardiac cycle.

pavor terreur [L.] terror. p. nocturnus t. nocturne a sleep disturbance of children causing them to cry out in fright and awake in panic, with poor recall of a nightmare. Repeated occurrences are called sleep terror disorder.

PAWP PAWP pulmonary artery wedge pressure.

Pb Pb lead¹ (L. plumbum).

PBI PBI protein-bound iodine.

PC PC phosphocreatine.

p.c. pc [L.] post cibum (after meals).

PCB PCB polychlorinated biphenyl.

PCC PCC prothrombin complex concentrate.

PCE PCE pseudocholinesterase; see cholinesterase.

PCI ICP percutaneous coronary intervention.

P_co2 P_co2 the partial pressure of carbon dioxide in the blood; also written P_CO2, pCO₂, or pCO₂.

PCOS SOPK polycystic ovary syndrome.

PCR ACP polymerase chain reaction.

PCT PCT porphyria cutanea tarda.

PCV PCV packed-cell volume.

PCWP PCWP pulmonary capillary wedge pressure.

Pd Pd palladium.

PDA PDA patent ductus arteriosus.

peak pic the top or upper limit of a graphic tracing or of any variable. kilovolts p. (kVp) p. de kilovolts the highest kilovoltage used in producing a radiograph.

pearl perle 1. a small rounded mass or body. 2. a rounded mass of tough sputum as seen in the early stages of an attack of bronchial asthma. epidermic p’s, epithelial p’s p. épidermiques rounded concentric masses of epithelial cells found in squamous cell carcinomas. Laënnec p’s p. de Laënnec soft casts of the smaller bronchial tubes expectorated in bronchial asthma.

pecten pecten pl. pectines [L.] 1. a comb; in anatomy, any of certain comblike structures. 2. p. analis. p. of anal canal, p. analis p. du canal anal the zone in the lower half of the anal canal between the pectinate line and the anal verge. p. ossis pubis p. ossis pubis pectineal line (2).

pectenosis myofibrome du canal anal stenosis of the anal canal due to an inelastic ring of tissue between the anal groove and anal crypts.

pectin pectine a polymer of sugar acids of fruit that forms gels with sugar at the proper pH; a purified form obtained from the acid extract of the rind of citrus fruits or from apple pomace is used as an antidiarrheal and as a pharmaceutic aid. Adj.: pectic.

pectinate pectiné comb-shaped.

pectineal pectinéal pertaining to the os pubis.

pectiniform pectiniforme comb-shaped.

pectoral pectoral thoracic.

pectoralis pectoralis [L.] thoracic.

pectoriloquy pectoriloquie voice sounds of increased resonance heard through the chest wall.

pectus poitrine pl. pectora [L.] thorax. p. carinatum pectus carinatum pigeon breast or chest; a group of deformities of the anterior chest wall marked by protrusion of the sternum and costal cartilages. p. excavatum pectus excavatum funnel breast or chest; a congenital deformity in which the sternum is depressed.

pedal pédal pertaining to the foot or feet.

pederasty pédérastie anal intercourse between a man and a boy.

pediatric pédiatrique pertaining to the health of children.

pediatrics pédiatrie the branch of medicine dealing with children, their development and care, and with the nature and treatment of diseases of children.

pedicel pédicelle a footlike part, especially any of the secondary processes of a podocyte.

pedicle pédicule a footlike, stemlike, or narrow basal part or structure.

pedicular pédiculaire pertaining to or caused by lice.

pediculicide pédiculicide 1. destroying lice. 2. an agent that destroys lice. Adj.: pediculicidal.

pediculosis pédiculose infestation with lice of the family Pediculidae, especially Pediculus humanus. p. pubis p. pubienne phthiriasis; infestation with the pubic louse Phthirus pubis.

pediculous pédiculeux infested with lice.

Pediculus Pediculus a genus of lice. P. humanus, a species feeding on human blood, is a major vector of typhus, trench fever, and relapsing fever; it has two subspecies: P. humanus capitis (head louse) found on the scalp hair, and P. humanus humanus (body, or clothes, louse) found on the body.

pediculus pediculus pl. pediculi [L.] 1. louse. 2. pedicle.

pedigree pedigree 1. lineage. 2. a list of ancestors. 3. a chart or diagram of an individual’s ancestors used in genetics in the analysis of inheritance of specific traits.

ped(o)- péd(o)- word element [Gr.]. child.

ped(o)- péd(i)- word element [L.]. foot.

pedodontics pédodontie the branch of dentistry dealing with the teeth and mouth conditions of children.

pedophilia pédophilie a paraphilia in which an adult has recurrent, intense sexual urges or sexually arousing fantasies of engaging or repeatedly engages in sexual activity with a prepubertal child. Adj.: pedophilic.

pedorthics podo-orthésie the design, manufacture, fitting, and modification of shoes and related foot appliances as prescribed for the amelioration of painful or disabling conditions of the foot and leg. Adj.: pedorthic.

peduncle pédoncule a stemlike connecting part, especially (a) a collection of nerve fibers coursing between different areas in the central nervous system, or (b) the stalk by which a nonsessile tumor is attached to normal tissue. Adj.: peduncular. cerebellar p’s p. cérébelleux three sets of paired bundles of the hindbrain (superior, middle, and inferior), connecting the cerebellum to the midbrain, pons, and medulla oblongata, respectively. cerebral p. p. cérébral the anterior half of the midbrain, divisible into an anterior part (crus cerebri) and a posterior part (tegmentum), which are separated by the substantia nigra. pineal p. p. pinéal habenula (2). p’s of thalamus p. du thalamus thalamic radiations.

pedunculus pedonculus pl. pedunculi [L.] peduncle.

PEEP PEP positive end-expiratory pressure; see under pressure.

PEF DEP peak expiratory flow.

PEG PEG pneumoencephalography; polyethylene glycol.

peg cheville a projecting structure. rete p’s crêtes épidermiques see under ridge.

pegademase pégadémase adenosine deaminase derived from bovine intestine and attached covalently to polyethylene glycol, used in replacement therapy for adenosine deaminase deficiency in immunocompromised patients.

pegaspargase pégaspargase l-asparaginase covalently linked to polyethylene glycol, used as an antineoplastic in the treatment of acute lymphoblastic leukemia.

peginterferon peginterféron a covalent conjugate of recombinant interferon and polyethylene glycol (PEG), with the former moiety responsible for the biological activity; conjugates of interferon alfa-2a and interferon alfa-2b are administered subcutaneously in the treatment of chronic hepatitis C infection.

peliosis péliose purpura. p. hepatis p. hépatique a mottled blue liver, due to blood-filled lacunae in the parenchyma.

pellagra pellagre a syndrome due to niacin deficiency (or failure to convert tryptophan to niacin), marked by dermatitis on parts of the body exposed to light or trauma, inflammation of the mucous membranes, diarrhea, and psychic disturbances. Adj.: pellagrous.

pellagroid pellagroïde resembling pellagra.

pellicle pellicule a thin scum forming on the surface of liquids.

pellucid pellucide translucent.

pelvic pelvien pertaining to the pelvis.

pelvicalyceal pyélocaliciel pyelocalyceal.

pelvicephalometry pelvicéphalométrie measurement of the fetal head in relation to the maternal pelvis.

pelvifixation pelvifixation surgical fixation of a displaced pelvic organ.

pelvimetry pelvimétrie measurement of the capacity and diameter of the pelvis.

pelviotomy pelviotomie 1. incision or transection of a pelvic bone. 2. pyelotomy.

pelvis pelvis, bassin pl. pelves [L.] the lower (caudal) portion of the trunk, bounded anteriorly and laterally by the two hip bones and posteriorly by the sacrum and coccyx. Also applied to any basinlike structure, e.g., the renal pelvis. Adj.: pelvic. android p. p. androïde one with a wedge-shaped inlet and narrow anterior segment; used to describe a female pelvis with characteristics usually found in the male. anthropoid p. p. anthropoïde a female pelvis in which the anteroposterior diameter of the inlet equals or exceeds the transverse diameter. assimilation p. p. d’assimilation one in which the ilia articulate with the vertebral column higher (high assimilation p.) or lower (low assimilation p.) than normal, the number of lumbar vertebrae being correspondingly decreased or increased. beaked p. p. en bec one with the pelvic bones laterally compressed and their anterior junction pushed forward. brachypellic p. b. brachypellique one in which the transverse diameter exceeds the anteroposterior diameter by 1 to 3 cm. contracted p. b. rétréci one showing a decrease of 1.5 to 2 cm in any important diameter; when all dimensions are proportionately diminished it is a generally contracted p. (p. justo minor). dolichopellic p. b. dolichopellique an elongated pelvis, the anteroposterior diameter being greater than the transverse diameter. extrarenal p. p. extrarénal see renal p. false p. faux pelvis the part of the pelvis superior to a plane passing through the iliopectineal lines. flat p. p. plat one in which the anteroposterior dimension is abnormally reduced. funnel-shaped p. p. en entonnoir one with a normal inlet but a greatly narrowed outlet. gynecoid p. p. gynécoïde the normal female pelvis: a rounded oval pelvis with well-rounded anterior and posterior segments. infantile p. p. infantile a generally contracted pelvis with an oval shape, high sacrum, and marked inclination of the walls. p. justo major p. justo major an unusually large gynecoid pelvis, with all dimensions increased. p. justo minor p. justo minor a small gynecoid pelvis, with all dimensions symmetrically reduced; see also contracted p. juvenile p. p. juvénile infantile p. p. major p. major false p. mesatipellic p. b. mésatipellique one in which the transverse diameter is equal to the anteroposterior diameter or exceeds it by no more than 1 cm. p. minor p. minor true p. platypellic p., platypelloid p. b. platypellique one shortened in the anteroposterior aspect, with a flattened transverse oval shape. rachitic p. b. rachitique one distorted as a result of rickets. renal p. p. rénal the funnel-shaped expansion of the upper end of the ureter into which the renal calices open; it is usually within the renal sinus, but under certain conditions a large part of it may be outside the kidney (extrarenal p.). scoliotic p. b. scoliotique one deformed as a result of scoliosis. split p. b. ouvert one with a congenital separation at the pubic symphysis. spondylolisthetic p. b. spondylolisthétique one in which the last, or rarely the fourth or third, lumbar vertebra is dislocated in front of the sacrum, more or less occluding the pelvic brim. true p. p. vrai the part of the pelvis inferior to a plane passing through the iliopectineal lines.

pelvospondylitis pelvispondylite inflammation of the pelvic portion of the spine. p. ossificans p. ossifiante ankylosing spondylitis.

pemirolast pémirolast a mast cell stabilizer that inhibits type I hypersensitivity reactions; administered topically as the potassium salt to prevent pruritus associated with allergic conjunctivitis.

pemoline pémoline a central nervous system stimulant used in the treatment of attentiondeficit/hyperactivity disorder.

pemphigoid pemphigoïde 1. resembling pemphigus. 2. any of a group of dermatological syndromes similar to but clearly distinguishable from the pemphigus group.

pemphigus pemphigus 1. a distinctive group of diseases marked by successive crops of bullae. 2. pemphigus vulgaris. benign familial p. p. familial bénin a hereditary, recurrent vesiculobullous dermatitis, usually involving the axillae, groin, and neck, with crops of lesions that regress over several weeks or months. p. erythematosus p. érythémateux a chronic form in which lesions are on the face and chest and resemble those of disseminated lupus erythematosus. p. foliaceus p. foliacé a chronic, generalized, vesicular and scaling eruption that resembles dermatitis herpetiformis and later exfoliative dermatitis. p. vegetans p. végétant a variant of pemphigus vulgaris in which the bullae are replaced by verrucoid hypertrophic vegetative masses. p. vulgaris p. vulgaire a rare relapsing disease with suprabasal, intraepidermal bullae of the skin and mucous membranes, fatal if untreated.

penbutolol penbutolol a beta-adrenergic blocking agent with intrinsic sympathomimetic activity; used as the sulfate salt in the treatment of hypertension.

penciclovir penciclovir a compound that inhibits viral DNA synthesis in herpesviruses 1 and 2, used in the treatment of recurrent herpes labialis.

pendelluft pendelluft the movement of air back and forth between the lungs, resulting in increased dead space ventilation.

pendular pendulaire having a pendulum-like movement.

pendulous pendant, pendulaire hanging loosely; dependent.

penectomy pénectomie surgical removal of the penis.

penetrance pénétrance in genetics, the frequency of expression of a genotype under defined conditions.

penetrometer pénétromètre an instrument for measuring the penetrating power of x-rays.

-penia -pénie word element [Gr.]. deficiency.

penicillamine pénicillamine a degradation product of penicillin that chelates certain heavy metals and also binds cystine and promotes its excretion; used in the treatment of Wilson disease, cystinuria, recurrent cystine renal calculi, and rheumatoid arthritis.

penicillin pénicilline any of a large group of natural (p. G, p.V) or semisynthetic antibacterial antibiotics derived directly or indirectly from strains of fungi of the genus Penicillium and other soil-inhabiting fungi, which exert a bactericidal as well as a bacteriostatic effect on susceptible bacteria by interfering with the final stages of the synthesis of peptidoglycan, a substance in the bacterial cell wall. The penicillins, despite their relatively low toxicity for the host, are active against many bacteria, especially gram-positive pathogens (streptococci, staphylococci, pneumococci); clostridia; some gram-negative forms (gonococci, meningococci); some spirochetes (Treponema pallidum and T. pertenue); and some fungi. Certain strains of some target species, e.g., staphylococci, secrete the enzyme penicillinase, which inactivates penicillin and confers resistance to the antibiotic.

penicillinase penicillinase a β-lactamase preferentially cleaving penicillin.

Penicillium Penicillium a genus of fungi.

penicilloyl polylysine pénicilloyle de polylysine benzylpenicilloyl polylysine.

penicillus penicillus pl. penicilli [L.] a brushlike structure, particularly any of the brushlike groups of arterial branches in the lobules of the spleen.

penile pénien of or pertaining to the penis.

penis pénis the male organ of urination and copulation. concealed p. p. caché a small penis hidden by a skin abnormality or the suprapubic fat pad. webbed p. verge palmée a penis that is enclosed by the skin of the scrotum, which extends onto its shaft.

penitis pénitis inflammation of the penis.

penniform penniforme shaped like a feather.

penoplasty pénoplastie phalloplasty.

pent(a)- pent(a)- word element [Gr.]. five.

pentagastrin pentagastrine a synthetic pentapeptide consisting of β-alanine and the C-terminal tetrapeptide of gastrin; used as a test of gastric secretory function.

pentamidine pentamidine an antiinfective used as the isethionate salt in the treatment of pneumocystis pneumonia, leishmaniasis, and early African trypanosomiasis.

pentastarch pentastarch an artificial colloid derived from a waxy starch and used as an adjunct in leukapheresis to increase the erythrocyte sedimentation rate.

pentazocine pentazocine a synthetic opioid analgesic, used in the form of the hydrochloride and lactate salts as an analgesic and anesthesia adjunct.

pentetate pentétate a salt, anion, ester, or complex of pentetic acid.

pentetic acid acide pentétique diethylenetriamine pentaacetic acid, DTPA; a chelating agent (iron) with the general properties of the edetates; used in preparing radiopharmaceuticals.

pentobarbital pentobarbital a short- to intermediate-acting barbiturate; the sodium salt is used as a hypnotic and sedative, usually presurgery, and as an anticonvulsant.

pentosan pentosan a carbohydrate derivative used in the form of p. polysulfate sodium as an antiinflammatory in the treatment of interstitial cystitis.

pentose pentose a monosaccharide containing five carbon atoms in a molecule.

pentostatin pentostatine an antineoplastic used in the treatment of hairy cell leukemia.

pentosuria pentosurie excretion of pentoses in the urine. alimentary p. p. alimentaire that occurring as a normal consequence of excessive ingestion of some fruits or their juices. essential p. p. essentielle a benign autosomal recessive deficiency of the enzyme l-xylulose reductase resulting in excessive urinary excretion of lxylulose.

pentoxifylline pentoxifylline a xanthine derivative that reduces blood viscosity; used for the symptomatic relief of intermittent claudication.

peplomer péplomère a subunit of a peplos.

peplos péplos envelope (2).

pepper poivre 1. any of various plants of the genus Piper, or their fruits, particularly the black pepper (P. nigrum), the common spice. 2. any of various plants of the genus Capsicum, or their fruits. cayenne p., red p. p. de Cayenne capsicum.

peppermint menthe poivrée the perennial herb Mentha piperita, or a preparation of its dried leaves and flowering tops, which have carminative, gastric stimulant, and counterirritant properties; used for gastrointestinal, liver, and gallbladder disturbances; also used in folk medicine and in homeopathy.

pepsin pepsine the proteolytic enzyme of gastric juice which catalyzes the hydrolysis of native or denatured proteins to form a mixture of polypeptides; it is formed from pepsinogen in the presence of acid or, autocatalytically, in the presence of pepsin.

pepsinogen pepsinogène a zymogen secreted by the chief cells of the gastric glands and converted into pepsin in the presence of gastric acid or of pepsin itself.

peptic peptique pertaining to pepsin or to digestion or to the action of gastric juices.

peptidase peptidase any of a subclass of proteolytic enzymes that catalyze the hydrolysis of peptide linkages; it comprises the exopeptidases and endopeptidases.

peptide peptide any of a class of compounds of low molecular weight that yield two or more amino acids on hydrolysis; known as di-, tri-, tetra-, (etc.) peptides, depending on the number of amino acids in the molecule. Peptides form the constituent parts of proteins. atrial natriuretic p. (ANP) p. atrial natriurétique a hormone involved in natriuresis and the regulation of renal and cardiovascular homeostasis. opioid p. p. opioïde opioid (2). glucagon-like p. (GLP) p. de type glucagon either of two intestinal peptide hormones (GLP-1 and GLP-2) secreted by the L cells in response to ingestion of nutrients, especially carbohydrates and fat-rich meals. GLP-1 inhibits gastric emptying and food intake and has several antidiabetic effects, including stimulation of insulin secretion and pancreatic islet proliferation; GLP-2 inhibits antral motility and gastric acid secretion and induces crypt cell proliferation.

peptidergic peptidergique of or pertaining to neurons that secrete peptide hormones.

peptidoglycan peptidoglycane a glycan (polysaccharide) attached to short cross-linked peptides; found in bacterial cell walls.

peptidyl-dipeptidase A peptide réticulé an enzyme that catalyzes the cleavage of a dipeptide from the C-terminal end of oligopeptides; when catalyzing the cleavage of angiotensin I to form the activated angiotensin II, it is also called angiotensin-converting enzyme; when catalyzing the cleavage and inactivation of kinins, it is also called kininase II.

peptogenic peptogène 1. producing pepsin or peptones. 2. promoting digestion.

peptolysis peptolyse the splitting up of peptones. Adj.: peptolytic.

peptone peptone a derived protein, or a mixture of cleavage products produced by partial hydrolysis of native protein. Adj.: peptonic.

Peptostreptococcaceae Peptostreptococcaceae a family of gram-positive, coccoid bacteria of the order Clostridiales.

per- per- word element [L.]. (1) throughout; completely; extremely; (2) in chemistry, a large amount; combination of an element in its highest valence.

peracid peracide an acid containing more than the usual quantity of oxygen.

peracute suraigu excessively acute or sharp.

per anum per anum [L.] through the anus.

percept percept the object perceived; the mental image of an object in space perceived by the senses.

perception perception the conscious mental registration of a sensory stimulus. Adj.: perceptive.

perceptivity perceptivité ability to receive sense impressions.

perchloric acid acide perchlorique a colorless volatile liquid, HClO₄, which can cause powerful explosions in the presence of organic matter or anything reducible.

percolate percoler 1. to strain; to submit to percolation. 2. to trickle slowly through a substance. 3. percolat a liquid that has been submitted to percolation.

percolation percolation the extraction of soluble parts of a drug by passing a solvent liquid through it.

percussion percussion the act of striking a part with short, sharp blows as an aid in diagnosing the condition of the underlying parts by the sound obtained. auscultatory p. p. auscultatoire auscultation of the sound produced by percussion. immediate p. p. immédiate that in which the blow is struck directly against the body surface. mediate p. p. médiée that in which a pleximeter is used. palpatory p. p. palpatoire a combination of palpation and percussion, affording tactile rather than auditory impressions.

percussor percuteur 1. a vibrator that produces relatively coarse movements. 2. percussion hammer.

percutaneous percutané performed through the skin.

perennial vivace lasting through the year or for several years.

perfect parfait of a fungus, capable of reproducing sexually (with sexual spores).

perforans perforant pl. perforantes [L.] penetrating; applied to various muscles, nerves, arteries, and veins.

perfusate perfusat a liquid that has been subjected to perfusion.

perfusion perfusion 1. the act of pouring over or through, especially the passage of a fluid through the vessels of a specific organ. 2. a liquid poured over or through an organ or tissue. luxury p. p. de luxe abnormally increased flow of blood to an area of the brain, leading to swelling.

pergolide pergolide a long-acting ergot derivative with dopaminergic properties; formerly used as the mesylate salt in the treatment of parkinsonism.

peri- péri- word element [Gr.]. around; near. See also words beginning para-.

periacinal périacinal around an acinus.

periacinous périacineux periacinal.

periadenitis périadénite inflammation of tissues around a gland. p. mucosa necrotica recurrens p. muqueuse nécrotique récurrente the more severe form of aphthous stomatitis, marked by recurrent attacks of aphtha-like lesions that begin as small firm nodules and enlarge, ulcerate, and heal to leave numerous atrophied scars on the oral mucosa.

periampullary périampoulaire around an ampulla.

periapical périapical around the apex of the root of a tooth.

periappendicitis périappendicite inflammation of the tissues around the vermiform appendix.

periarteritis périartérite inflammation of the external coats of an artery and of the tissues around the artery. p. nodosa p. noueuse 1. polyarteritis nodosa. 2. a group comprising polyarteritis nodosa, allergic granulomatous angiitis, and many systemic necrotizing vasculitides with clinicopathologic characteristics overlapping these two.

periarthritis périarthrite inflammation of tissues around a joint.

periarticular périarticulaire around a joint.

periaxial périaxial near or around an axis.

peribronchiolitis péribronchiolite inflammation of tissues around the bronchioles.

peribronchitis péribronchite bronchitis with inflammation and thickening of tissues around the bronchi.

pericallosal péricalleux around the corpus callosum.

pericalyceal péricaliciel near or around a renal calyx.

pericardial 1. péricardique pertaining to the pericardium. 2. péricardiaque surrounding the heart.

pericardiectomy péricardiectomie removal of all or part of the pericardium.

pericardiocentesis péricardiocentèse surgical puncture of the pericardial cavity for the aspiration of fluid.

pericardiolysis péricardiolyse the operative freeing of adhesions between the visceral and parietal pericardium.

pericardiophrenic péricardiophrénique pertaining to the pericardium and diaphragm.

pericardiorrhaphy péricardiorraphie suture of the pericardium.

pericardiostomy péricardiostomie creation of an opening into the pericardium, usually for the drainage of effusions.

pericardiotomy péricardiotomie incision of the pericardium.

pericarditis péricardite inflammation of the pericardium. Adj.: pericarditic. adhesive p. p. adhésive a condition due to the presence of dense fibrous tissue between the parietal and visceral layers of the pericardium. constrictive p. p. constrictive a chronic form in which a fibrotic, thickened, adherent pericardium restricts diastolic filling and cardiac output, usually resulting from a series of events beginning with fibrin deposition on the pericardial surface followed by fibrotic thickening and scarring and obliteration of the pericardial space. fibrinous p., fibrous p. p. fibrineuse that characterized by a fibrinous exudate, sometimes accompanied by a serous effusion; usually manifested as a pericardial friction rub. p. obliterans, obliterating p. p. oblitérante adhesive pericarditis that leads to obliteration of the pericardial cavity.

pericardium péricarde the fibroserous sac enclosing the heart and the roots of the great vessels. Adj.: pericardial. adherent p. p. adhérent one abnormally connected with the heart by dense fibrous tissue.

pericecitis inflammation des tissus entourant le cæcum inflammation of the tissues around the cecum.

pericementitis péricémentite periodontitis.

pericholangitis péricholangite inflammation of the tissues around the bile ducts.

pericholecystitis péricholécystite inflammation of tissues around the gallbladder.

perichondrium périchondre the layer of fibrous connective tissue investing all cartilage except the articular cartilage of synovial joints. Adj.: perichondral.

perichordal périchordal around the notochord.

perichoroidal périchoroïdien surrounding the choroid coat.

pericolitis péricolite inflammation around the colon, especially of its peritoneal coat.

pericolonitis péricolonite pericolitis.

pericolpitis péricolpite inflammation of tissues around the vagina.

pericoronal péricoronaire around the crown of a tooth.

pericranitis péricranite inflammation of the pericranium.

pericranium péricrâne the periosteum of the skull. Adj.: pericranial.

pericyte péricyte a type of elongated cell having the power of contraction, found wrapped about the outside of precapillary arterioles, postcapillary venules, and capillaries.

pericytial péricytaire around a cell.

peridental péridentaire periodontal.

periderm périderme 1. the outer layer of the bilaminar fetal epidermis, generally disappearing before birth. 2. the cuticle (eponychium) and hyponychium considered together. Adj.: peridermal.

peridesmium péridesme the areolar membrane that covers the ligaments.

peridiverticulitis péridiverticulite inflammation of the structures around a diverticulum of the intestine.

periductal péricanalaire surrounding a duct, particularly of the mammary gland.

periduodenitis périduodénite inflammation around the duodenum.

periencephalitis périencéphalite meningoencephalitis.

perienteritis périentérite inflammation of the peritoneal coat of the intestines.

periesophagitis périœsophagite inflammation of tissues around the esophagus.

perifollicular périfolliculaire surrounding a follicle, particularly a hair follicle.

perifolliculitis périfolliculite inflammation around the hair follicles.

perigangliitis périganglionite inflammation of tissues around a ganglion.

perigastritis périgastrite inflammation of the peritoneal coat of the stomach.

perihepatitis périhépatite inflammation of the peritoneal capsule of the liver and the surrounding tissue.

peri-islet péri-insulaire around the islets of Langerhans.

perijejunitis périjéjunite inflammation around the jejunum.

perikaryon péricaryon the cell body as distinguished from the nucleus and the processes; applied particularly to neurons.

perilabyrinthitis périlabyrinthite circumscribed labyrinthitis.

perilymph périlymphe the fluid within the space separating the membranous and osseous labyrinths of the ear.

perilymphangitis périlymphangite inflammation around a lymphatic vessel.

perilymphatic périlymphatique 1. pertaining to the perilymph. 2. around a lymphatic vessel.

perimeningitis périméningite pachymeningitis.

perimenopause périménopause the time just before and after menopause. Adj.: perimenopausal.

perimetrium périmétrium the tunica serosa surrounding the uterus.

perimyositis périmyosite inflammation of connective tissue around a muscle.

perimysium périmysium pl. perimysia the connective tissue demarcating a fascicle of skeletal muscle fibers. See Plate 7. Adj.: perimysial.

perinatal périnatal relating to the period shortly before and after birth; from the twentieth to twenty-ninth week of gestation to one to four weeks after birth.

perinatology périnatologie the branch of medicine (obstetrics and pediatrics) dealing with the fetus and infant during the perinatal period.

perineal périnéal pertaining to the perineum.

perineocele périnéocèle perineal hernia.

perineoplasty périnéoplastie plastic repair of the perineum.

perineorrhaphy périnéorraphie suture of the perineum.

perineotomy périnéotomie incision of the perineum.

perineovaginal périnéovaginal pertaining to or communicating with the perineum and vagina.

perinephric périnéphrétique perirenal; surrounding the kidney.

perinephritis périnéphrite inflammation of the perinephrium.

perinephrium périnéphrium the peritoneal envelope and other tissues around the kidney. Adj.: perinephrial.

perineum périnée 1. the region and associated structures occupying the pelvic outlet and beneath the pelvic diaphragm; bounded anteriorly by the pubic symphysis, anterolaterally by the ischiopubic rami and the ischial tuberosities, posterolaterally by the sacrotuberous ligaments, and posteriorly by the coccyx. 2. the region between the thighs, bounded in the male by the scrotum and anus and in the female by the vulva and anus, and containing the roots of the external genitalia.

perineuritis périnévrite inflammation of the perineurium.

perineurium périnèvre an intermediate layer of connective tissue in a peripheral nerve, surrounding each bundle of nerve fibers. See Plate 14. Adj.: perineurial.

perinuclear périnucléaire near or around a nucleus.

period période an interval or division of time. ejection p. p. d’éjection the second phase of ventricular systole, being the interval between the opening and closing of the semilunar valves, during which the blood is discharged into the aortic and pulmonary arteries; it is divided into a p. of rapid ejection followed by a p. of reduced ejection. gestation p. p. de gestation the duration of pregnancy, in humans being about 266 days (38 weeks) from the time of fertilization until birth. In obstetrics, it is instead considered to begin on the first day of the woman’s last normal menstrual period prior to fertilization, thus being about 280 days (40 weeks). incubation p. périnée 1. the interval of time required for development. 2. the interval between the receipt of infection and the onset of the consequent illness or the first symptoms of the illness. 3. the interval between the entrance into a vector of an infectious agent and the time at which the vector is capable of transmitting the infection. latency p. p. de latence 1. latent p. 2. see under stage. latent p. p. de latence a seemingly inactive period, as that between exposure to an infection and subsequent illness, or that between the instant of stimulation and the beginning of response. menstrual p. p. menstruelle the time of menstruation. pacemaker refractory p. p. réfractaire (de pacemaker) the period immediately following either pacemaker sensing or pacing, during which improper inhibition of the pacemaker by inappropriate signals is prevented by inactivation of pacemaker sensing. quarantine p. pyrrole 1. the length of time that must elapse before a person exposed to contagion is regarded as incapable of transmitting or acquiring the disease (see also quarantine). 2. a period of detention of vessels, vehicles, or travelers coming from infected or suspected ports or places. refractory p. p. réfractaire the period of depolarization and repolarization of the cell membrane after excitation; during the first portion (absolute refractory p.), the nerve or muscle fiber cannot respond to a second stimulus, whereas during the relative refractoryperiod, it can respond only to a strong stimulus. safe p. p. sûre the period during the menstrual cycle when conception is considered least likely to occur; it is approximately the ten days after menstruation begins and the ten days preceding menstruation. sphygmic p. p. sphygmique ejection p. Wenckebach p. p. de Wenckebach the steadily lengthening P-R interval occurring in successive cardiac cycles in Wenckebach block.

periodic périodique 1. recurring at regular intervals of time. 2. recurring intermittently or occasionally.

periodicity périodicité recurrence at regular intervals of time.

periodontal parodontal 1. pertaining to the periodontal ligament or periodontium. 2. near or around a tooth.

periodontics périodontie the branch of dentistry dealing with the study and treatment of diseases of the periodontium.

periodontitis périodontite inflammatory reaction of the periodontium.

periodontium périodonte pl. periodontia the tissues investing and supporting the teeth, including the cementum, periodontal ligament, alveolar bone, and gingiva. In official nomenclature, restricted to the periodontal ligament.

periodontosis périodontose a degenerative disorder of the periodontal structures, marked by tissue destruction.

perionychium périonychium eponychium (1).

perioophoritis périoophorite, périovarite inflammation of tissues around the ovary.

perioophorosalpingitis périoophorosalpingite inflammation of tissues around an ovary and uterine tube.

perioperative périopératoire pertaining to the period extending from the time of hospitalization for surgery to the time of discharge.

periophthalmic périophtalmique around the eye.

perioptometry périoptométrie measurement of acuity of peripheral vision or of limits of the visual field.

periorbita périorbite periosteum of the bones of the orbit, or eye socket. Adj.: periorbital.

periorbititis périorbitite inflammation of the periorbita.

periorchitis périorchite inflammation of the tunica vaginalis testis.

periosteal périostique, périostal, périostéal pertaining to the periosteum.

periosteitis périostéite periostitis.

periosteoma périostéome a morbid bony growth surrounding a bone.

periosteomyelitis périostéomyélite inflammation of the entire bone, including periosteum and marrow.

periosteophyte périostéophyte a bony growth on the periosteum.

periosteotomy périostéotomie incision of the periosteum.

periosteum périoste a specialized connective tissue covering all bones and having bone-forming potentialities.

periostitis périostite inflammation of the periosteum.

periostosis périostose abnormal deposition of periosteal bone; the condition manifested by development of periosteomas.

periotic 1. périotique situated about the ear, especially the internal ear. 2. portion pétreuse et mastoïdienne de l’os temporal the petrous and mastoid portions of the temporal bone, at one stage a distinct bone.

periovular périovulaire 1. surrounding an ovum. 2. around the time of ovulation.

peripapillary péripapillaire around the optic papilla.

peripartum péripartum occurring during the last month of gestation or the first few months after delivery, with reference to the mother.

peripherad périphérique toward the periphery.

periphery périphérie an outward surface or structure; the portion of a system outside the central region. Adj.: peripheral.

periphlebitis périphlébite inflammation of tissues around a vein, or of the external coat of a vein.

Periplaneta Periplaneta a genus of roaches, including P. americana, the American cockroach, and P. australasiae, the Australian cockroach.

periplasmic périplasmique around the plasma membrane; between the plasma membrane and the cell wall of a bacterium.

periproctitis périproctite inflammation of tissues around the rectum and anus.

periprostatitis périprostatite inflammation of tissues around the prostate.

peripylephlebitis péripyléphlébite inflammation of tissues around the portal vein.

perirectitis périrectite periproctitis.

perirenal périrénal perinephric.

perisalpingitis périsalpingite inflammation of the tissues and peritoneum around a uterine tube.

perisigmoiditis périsigmoïdite inflammation of the peritoneum of the sigmoid flexure.

perisinusitis périsinusite inflammation of tissues about a sinus.

perisplanchnitis périsplanchnite inflammation of tissues around the viscera.

perisplenitis périsplénite inflammation of the peritoneal surface of the spleen.

perispondylitis périspondylite inflammation of tissues around a vertebra.

peristalsis péristalsis the wormlike movement by which the alimentary canal or other tubular organs having both longitudinal and circular muscle fibers propel their contents, consisting of a wave of contraction passing along the tube for variable distances. Adj.: peristaltic.

peristaphyline péristaphylin around the uvula.

peritectomy péritectomie excision of a ring of conjunctiva around the cornea in treatment of pannus.

peritendineum péritendinéum connective tissue investing larger tendons and extending between the fibers composing them.

peritendinitis péritendinite tenosynovitis.

peritenonitis périténonite tenosynovitis.

perithelioma périthéliome hemangiopericytoma.

perithelium périthélium the connective tissue layer surrounding the capillaries and smaller vessels.

perithyroiditis périthyroïdite inflammation of the capsule of the thyroid gland.

peritomy péritomie incision of the conjunctiva and subconjunctival tissue about the entire circumference of the cornea.

peritoneal péritonéal pertaining to the peritoneum.

peritonealgia péritonéalgie pain in the peritoneum.

peritoneocentesis péritonéocentèse paracentesis of the abdominal cavity.

peritoneoscopy péritonéoscopie laparoscopy.

peritoneovenous péritonéoveineux communicating with the peritoneal cavity and the venous system.

peritoneum péritoine the serous membrane lining the walls of the abdominal and pelvic cavities (parietal p.) and investing the contained viscera (visceral p.), the two layers enclosing a potential space, the peritoneal cavity. Adj.: peritoneal.

peritonitis péritonitie inflammation of the peritoneum, which may be due to chemical irritation or bacterial invasion.

peritonsillar péri-amygdalien around a tonsil.

peritonsillitis péri-amygdalite inflammation of peritonsillar tissues.

peritrichous péritriche 1. having flagella around the entire surface; said of bacteria; sometimes used to describe the flagella themselves. 2. having flagella around the cytostome only; said of Ciliophora.

peritubular péritubulaire situated around or near tubules.

periumbilical périombilical around the umbilicus.

periungual périunguéal around the nail.

periureteritis périurétérite inflammation of tissues around a ureter.

periurethritis périuréthrite inflammation of the tissues around the urethra.

perivaginitis périvaginite pericolpitis.

perivascular périvasculaire near or around a vessel.

perivasculitis périvascularite inflammation of the tissue surrounding a blood or lymph vessel.

perivesical périvésical near the urinary bladder.

perivesiculitis périvésiculite inflammation of tissue around the seminal vesicle.

perlèche perlèche inflammation with exudation, maceration, and fissuring at the labial commissures.

permanganate permanganate a salt containing the ion.

permeable perméable allowing passage of a substance.

permeability perméabilité the property or state of being permeable.

permease perméase former name for transport protein.

permeate 1. infiltrer (s’) to penetrate or pass through, as through a filter. 2. filtrat the constituents of a solution or suspension that pass through a filter.

permethrin perméthrine a topical insecticide used in the treatment of infestations by Pediculus humanus capitis, Sarcoptes scabiei, or any of various ticks; also applied to objects such as furniture and bedding.

permselectivity permséléctivité restriction of permeation of macromolecules across a glomerular capillary wall on the basis of molecular size, charge, and physical configuration.

pernicious pernicieux tending toward a fatal issue.

pernio pernion pl. perniones [L.] chilblain.

pero- péro- word element [Gr.]. deformity; maimed.

peromelia péromélie severe dysmelia.

peroneal péronier pertaining to the fibula or to the lateral aspect of the leg; fibular.

peroral peroral performed or administered through the mouth.

per os per os [L.] by mouth.

peroxidase peroxydase any of a group of ironporphyrin enzymes that catalyze the oxidation of some organic substrates in the presence of hydrogen peroxide.

peroxide peroxyde that oxide of any element containing more oxygen than any other; more correctly applied to compounds having such linkage as —O—O—.

peroxisome péroxysome a microbody (q.v.), present in all animal cells except erythrocytes and many plant cells, containing enzymes that participate in a variety of oxidative processes, including reactions involving hydrogen peroxide, purine metabolism, cellular lipid metabolism, and gluconeogenesis.

perphenazine perphénazine a phenothiazine used as an antipsychotic and as an antiemetic.

per primam intentionem per primam intentionem [L.] by first intention; see under healing. Written also per primam.

per rectum per rectum, rectal [L.] by way of the rectum.

per secundam intentionem per secundam intentionem [L.] by second intention; see under healing. Written also per secundam.

perseveration persévération persistent repetition of the same verbal or motor response to varied stimuli; continuance of activity after cessation of the causative stimulus.

persona persona [L.] in jungian psychology, the personality mask or facade presented by a person to the outside world, as opposed to the anima, the inner being.

personality personnalité the characteristic, relatively stable, and predictable way a person thinks, feels, and behaves, including conscious attitudes, values, and styles, and also unconscious conflicts and defense mechanisms. cyclothymic p. p. cyclothymique a temperament characterized by rapid, frequent swings between sad and cheerful moods. split p. dédoublement de la p. a colloquial term used for either schizophrenia or dissociative identity disorder.

perspiration perspiration 1. sweating. 2. sweat.

persulfate persulfate a salt of persulfuric acid.

per tubam per tubam [L.] through a tube.

pertussis coqueluche whooping cough; an infectious disease caused by Bordetella pertussis, marked by inflammation of the respiratory tract and peculiar paroxysms of cough, ending in a prolonged crowing or whooping respiration.

pertussoid coqueluchoïde 1. resembling whooping cough. 2. an influenzal cough resembling that of whooping cough.

per vaginam per vaginam [L.] through the vagina.

perversion perversion 1. deviation from the normal course. 2. sexual perversion; see under deviation.

pes pes pl. pedes [L.] 1. foot. 2. any footlike part.

pessary pessaire 1. an instrument placed in the vagina to support the uterus or rectum or as a contraceptive device. 2. a medicated vaginal suppository.

pestilence pestilence a virulent contagious epidemic or infectious epidemic disease. Adj.: pestilential.

pestle pilon an implement for pounding drugs in a mortar.

PET TEP positron emission tomography.

peta- (P) péta- a word element used in naming units of measurement to designate a quantity 10¹⁵ (a quadrillion) times the unit to which it is joined.

-petal -pète word element [L.]. directed or moving toward.

petechia pétéchie pl. petechiae [L.] a minute red spot due to escape of a small amount of blood. Adj.: petechial.

petiole pétiole a stalk or pedicle. epiglottic p. p. épiglottique the pointed lower end of the epiglottic cartilage, attached to the thyroid cartilage.

petiolus petiolus petiole.

petit mal petit mal [Fr.] see under epilepsy.

petrolatum vaseline, gel de paraffine a purified mixture of semisolid hydrocarbons obtained from petroleum; used as an ointment base, protective dressing, and soothing application to the skin. liquid p. v. liquide mineral oil.

petroleum pétrole a thick natural mixture of gaseous, liquid, and solid hydrocarbons obtained from beneath the surface of the earth. p. benzin éther de pétrole a colorless, volatile, flammable fraction from petroleum distillation, containing largely hydrocarbons of the methane series; it has been variously described as a special grade of ligroin or as a separate but similar fraction with a lower boiling range. It is used chiefly as an extractive solvent.

petromastoid antérocérébelleux 1. pertaining to the petrous portion of the temporal bone and its mastoid process. 2. otocranium (2).

petro-occipital pétro-occipital pertaining to the petrous portion of the temporal bone and to the occipital bone.

petrosal pétreux pertaining to the petrous part of the temporal bone.

petrositis pétrosite inflammation of the petrous part of the temporal bone.

petrosphenoid pétrosphénoïdal pertaining to the petrous portion of the temporal bone and to the sphenoid bone.

petrosquamous pétrosquameux pertaining to the petrous and squamous parts of the temporal bone.

petrous pétreux resembling a rock; hard; stony.

pexis pexie 1. the fixation of matter by a tissue. 2. surgical fixation. Adj.: pexic.

-pexy -pexie word element [Gr.]. surgical fixation. Adj.: -pectic.

peyote peyotl a stimulant drug from mescal buttons, whose active principle is mescaline; used by North American Indians in certain ceremonies to produce an intoxication marked by feelings of ecstasy.

pg pg picogram.

pH pH the symbol relating the hydrogen ion (H⁺) concentration or activity of a solution to that of a given standard solution. Numerically the pH is approximately equal to the negative logarithm of H⁺ concentration expressed in molarity. pH 7 is neutral; above it alkalinity increases and below it acidity increases.

phac(o)- phac(o)- word element [Gr.]. lens. See also words beginning phak(o)-.

phacoanaphylaxis phacoanaphylaxie hypersensitivity to the protein of the crystalline lens of the eye, induced by escape of material from the lens capsule.

phacocele phacocèle hernia of the eye lens.

phacocystectomy phacocystectomie excision of part of the lens capsule for cataract.

phacocystitis phacocystite inflammation of the capsule of the eye lens.

phacoemulsification phacoémulsification a method of cataract extraction in which the lens is fragmented by ultrasonic vibrations and simultaneously irrigated and aspirated.

phacoerysis phacoérisis removal of the eye lens in cataract by suction.

phacoid phacoïde shaped like a lens.

phacoiditis phacoïdite phakitis.

phacolysis phacolyse dissolution or discission of the eye lens. Adj.: phacolytic.

phacomalacia phacomalacie softening of the lens; a soft cataract.

phacometachoresis phacométachoresis displacement of the eye lens.

phacosclerosis phacosclérose hardening of the crystalline lens; a hard cataract.

phacoscope phacoscope instrument for viewing accommodative changes of the eye lens.

phacotoxic phacotoxique exerting a deleterious effect upon the crystalline lens.

phaeohyphomycosis phaeo-hyphomycose any opportunistic infection caused by dematiaceous fungi.

phage phage bacteriophage.

-phage -phage word element [Gr.]. one that eats or destroys.

phagedena phagédène ulceration that spreads rapidly and causes sloughing. Adj.: phagedenic.

phagedenic phagédénique pertaining to or characterized by phagedena.

-phagia -phagie word element [Gr.]. eating; swallowing.

phag(o)- phag(o)- word element [Gr.]. eating; ingestion.

phagocyte phagocyte any cell that ingests microorganisms or other cells and foreign particles, such as a microphage, macrophage, or monocyte. Adj.: phagocytic.

phagocytolysis phagocytolyse destruction of phagocytes. Adj.: phagocytolytic.

phagocytosis phagocytose the engulfing of microorganisms or other cells and foreign particles by phagocytes. Adj.: phagocytotic.

phagosome phagosome a membrane-bound vesicle in a phagocyte containing the phagocytized material.

phagotype phagotype phage type; see under type.

-phagy -phagie see -phagia.

phakitis phakite inflammation of the crystalline lens.

phak(o)- phac(o)- see phac(o)-.

phakoma phacome any of the hamartomas found in the phakomatoses, such as the herald lesions of tuberous sclerosis. See also tuber (2).

phakomatosis phacomatose pl. phakomatoses any of a group of congenital hereditary developmental anomalies having selective involvement of tissues of ectodermal origin, which develop disseminated glial hamartomas; examples are neurofibromatosis, tuberous sclerosis, Sturge-Weber syndrome, and von Hippel-Lindau disease.

phalangeal phalangien pertaining to a phalanx.

phalangectomy phalangectomie excision of a phalanx.

phalangitis phalangite inflammation of one or more phalanges.

phalang(o)- phalang(o)- word element [Gr.]. phalanx or phalanges.

phalanx phalange pl. phalanges [Gr.] 1. any bone of a finger or toe; there are two for the thumb and great toe and and three for each of the other fingers and toes. See Plate 1. 2. any one of a set of plates that are disposed in rows and make up the reticular membrane of the organ of Corti. Adj.: phalangeal.

phallectomy phallectomie penectomy.

phalli phalli plural of phallus.

phallic phallique pertaining to or resembling a phallus.

phallitis phallite penitis.

phalloidin phalloïdine a hexapeptide poison from the mushroom Amanita phalloides, which causes asthenia, vomiting, diarrhea, convulsions, and death.

phalloplasty phalloplastie plastic surgery of the penis.

phallus phallus pl. phalli 1. penis. 2. a representation of the penis. 3. the primordium of the penis or clitoris that develops from the genital tubercle.

phantasm fantasme an impression or image not evoked by actual stimuli, and usually recognized as false by the observer.

phantom fantôme 1. phantasm. 2. a model of the body or a body part. 3. a device for simulating the in vivo effect of radiation on tissues.

phantosmia phantosmie a parosmia consisting of a sensation of smell in the absence of any external stimulus.

phar, pharm phar pharmacy; pharmaceutical; pharmacopeia.

pharmaceutic pharmaceutique pharmaceutical (1).

pharmaceutical pharmaceutique 1. pertaining to pharmacy or drugs. 2. a medicinal drug.

pharmacist pharmacien one who is licensed to prepare and sell or dispense drugs and compounds, and to make up prescriptions.

pharmaco- pharmaco- word element [Gr.]. drug; medicine.

pharmacoangiography pharmacoangiographie angiography in which visualization is enhanced by manipulating the flow of blood by the administration of vasodilating and vasoconstricting agents.

pharmacodynamics pharmacodynamie the study of the biochemical and physiological effects of drugs and the mechanisms of their actions, including the correlation of their actions and effects with their chemical structure. Adj.: pharmacodynamic.

pharmacogenetics pharmacogénétique the clinical study of inherited variation in the nature of responses to drugs, focusing on single genes. In practice, often used interchangeably with pharmacogenomics.

pharmacogenomics pharmacogénomique the study of the inherited variations in many genes that dictate drug response and the way these can be used to predict individual responses to a drug. In practice, often used interchangeably with pharmacogenetics.

pharmacognosy pharmacognosie the branch of pharmacology dealing with natural drugs and their constituents.

pharmacokinetics pharmacocinétique the action of drugs in the body over a period of time, including the processes of absorption, distribution, localization in tissues, biotransformation, and excretion. Adj.: pharmacokinetic.

pharmacologic pharmacologique pertaining to pharmacology or to the properties and reactions of drugs.

pharmacologist pharmacologiste one who makes a study of the actions of drugs.

pharmacology pharmacologie the science that deals with the origin, nature, chemistry, effects, and uses of drugs; it includes pharmacognosy, pharmocokinetics, pharmacodynamics, pharmacotherapeutics, and toxicology.

pharmacopeia pharmacopée an authoritative treatise on drugs and their preparations. See also USP. Adj.: pharmacopeial. United States P. United States Pharmacopeia see under U.

pharmacotherapy pharmacothérapie treatment of disease with medicines.

pharmacy pharmacie 1. the branch of the health sciences dealing with the preparation, dispensing, and proper utilization of drugs. 2. a place where drugs are compounded or dispensed.

Pharm D DP [L.] Pharmaciae Doctor (Doctor of Pharmacy).

pharyngalgia pharyngalgie pharyngodynia.

pharyngeal pharyngien pertaining to the pharynx.

pharyngectomy pharyngectomie excision of part of the pharynx.

pharyngismus pharyngisme muscular spasm of the pharynx.

pharyngitis pharyngite sore throat; inflammation of the pharynx. Adj.: pharyngitic.

pharyng(o)- pharyng(o)- word element [Gr.]. pharynx.

pharyngocele pharyngocèle herniation or cystic deformity of the pharynx.

pharyngodynia pharyngodynie pain in the pharynx.

pharyngoesophageal pharyngo-œsophagien pertaining to the pharynx and esophagus.

pharyngomycosis pharyngomycose any fungal infection of the pharynx.

pharyngoparalysis pharyngoparalysie paralysis of the pharyngeal muscles.

pharyngoplegia pharyngoplégie pharyngoparalysis.

pharyngoscopy pharyngoscopie direct visual examination of the pharynx.

pharyngostenosis pharyngosténose narrowing of the pharynx.

pharyngotomy pharyngotomie incision of the pharynx.

pharynx pharynx the throat; the musculomembranous cavity behind the nasal cavities, mouth, and larynx, communicating with them and with the esophagus.

phase phase 1. one of the aspects or stages through which a varying entity may pass. 2. in physical chemistry, any physically or chemically distinct, homogeneous, and mechanically separable part of a system. Adj.: phasic. erythrocytic p. p. érythrocytaire that phase in the life cycle of a malarial plasmodium in which the parasites multiply in the red blood cells. five p’s cinq p. in traditional Chinese medicine, a set of dynamic relations (designated earth, metal, water, wood, and fire) that can be used to categorize relationships among phenomena. follicular p. p. folliculaire the first part of the ovarian cycle, lasting from the end of the menstrual phase until ovulation and corresponding to the proliferative phase of the uterine cycle; it is characterized by the development of a dominant ovarian follicle. G₀ p. p. G₀ a special subtype of the G₁ phase, in which cells carry out their normal physiologic functions but do not proliferate. G₁ p. p. G₁ the part of the cell cycle lasting from the end of cell division (the M phase) until the start of DNA synthesis (the S phase). G₂ p. p. G₂ a relatively quiescent part of the cell cycle, lasting from the end of the S phase until the start of cell division, during which the accuracy of DNA replication is checked and faulty sections repaired. luteal p. p. lutéale the phase of the ovarian cycle, lasting from ovulation to menstruation, during which the ovarian follicle transforms into the corpus luteum; it corresponds to the secretory phase in the uterus. M p. p. M the part of the cell cycle during which mitosis occurs; subdivided into prophase, metaphase, anaphase, and telophase. menstrual p. p. menstruelle the phase of the human menstrual cycle, following the luteal phase and occurring only if fertilization has not taken place. The corpus luteum regresses and is shed through menstruation and growth begins for the ovarian follicle, leading to the follicular phase. proliferative p. p. proliférative the phase of the uterine cycle, corresponding to the follicular phase of the ovarian cycle, during which the functional layer of the endometrium is repaired and proliferates following menstruation . S p. p. S the part of the cell cycle between the G₁ and G₂ phases, during which DNA is synthesized and chromosomes are replicated. secretory p. p. sécrétoire the phase of the uterine cycle, corresponding to the luteal phase of the ovarian cycle, characterized by thickening and increased vascularity of the endometrium.

phasmid phasmide 1. either of the two caudal chemoreceptors occurring in certain nematodes (Phasmidia). 2. any nematode containing phasmids.

phenacetin phénacétine an analgesic and antipyretic, whose major metabolite is acetaminophen, now little used because of its toxicity.

phenanthrene phénanthrène a tricyclic aromatic hydrocarbon occurring in coal tar; toxic and carcinogenic.

phenarsazine chloride chlorure de phénarsazine diphenylamine chlorarsine.

phenazone phénazone antipyrine.

phenazopyridine phénazopyridine a urinary tract analgesic, used as the hydrochloride salt.

phencyclidine (PCP) phencyclidine a potent veterinary analgesic and anesthetic, used as a drug of abuse in the form of the hydrochloride salt; its abuse by humans may lead to serious psychological disturbances.

phendimetrazine phendimétrazine a sympathomimetic amine used as an anorectic in the form of the tartrate salt.

phenelzine phénelzine a monoamine oxidase inhibitor used as the sulfate salt as an antidepressant and in the prophylaxis of migraine.

phenindamine phénindamine an antihistamine with anticholinergic and sedative effects, used as the tartrate salt.

pheniramine phéniramine an antihistamine with anticholinergic and sedative effects, used as the maleate salt.

phenmetrazine phenmétrazine a central nervous system stimulant formerly used as an anorectic in the form of the hydrochloride salt.

phen(o)- phén(o)-word element [Gr.]. 1. showing; displaying. 2. a compound derived from benzene.

phenobarbital phénobarbital a long-acting barbiturate, used as the base or sodium salt as a sedative, hypnotic, and anticonvulsant.

phenocopy phénocopie 1. an environmentally induced phenotype mimicking one usually produced by a specific genotype. 2. an individual exhibiting such a phenotype.

phenol phénol 1. an extremely poisonous compound, C₆H₅OH, which is caustic and disinfectant; used as a pharmaceutic preservative and in dilution as an antimicrobial and topical anesthetic and antipruritic. Poisoning, due to ingestion or transdermal absorption, causes symptoms including colic, local irritation, corrosion, seizures, cardiac arrhythmias, shock, and respiratory arrest. 2. any organic compound containing one or more hydroxyl groups attached to an aromatic carbon ring.

phenolate phénoler 1. to treat with phenol for purposes of sterilization. 2. phénolate a salt formed by union of a base with phenol, in which a monovalent metal, such as sodium or potassium, replaces the hydrogen of the hydroxyl group.

phenolphthalein phénolphthaléine a cathartic and pH indicator, with a range of 8.5 to 9.0.

phenomenon phénomène pl. phenomena any sign or objective symptom; an observable occurrence or fact. booster p. p. de rappel on a tuberculin test, an initial false-negative result due to a diminished amnestic response, becoming positive on subsequent testing. dawn p. p. de l’aube the early morning increase in plasma glucose concentration and thus insulin requirement in patients with type 1 diabetes mellitus. Koebner p. p. de Koebner a cutaneous response seen in certain dermatoses, manifested by the appearance on uninvolved skin of lesions typical of the skin disease at the site of trauma, on scars, or at points where articles of clothing produce pressure. Marcus Gunn pupillary p. p. pupillaire de Marcus Gunn with unilateral optic nerve or retinal disease, a difference between the pupillary reflexes of the two eyes; on the affected side there is abnormally slight contraction or even dilatation of the pupil when a light is shone in the eye. no-reflow p. p. de non reflux when cerebral blood flow is restored following prolonged global cerebral ischemia, there is initial hyperemia followed by a gradual decline in perfusion until there is almost no blood flow. Somogyi p. p. de Somogyi a rebound phenomenon occurring in diabetes: overtreatment with insulin induces hypoglycemia, thus initiating hormone release; this stimulates lipolysis, gluconeogenesis, and glycogenolysis, which in turn cause rebound hyperglycemia and ketosis.

phenothiazine phénothiazine any of a group of antipsychotic agents having a similar tricyclic structure and acting as potent alpha- adrenergic and dopaminergic blocking agents, as well as having hypotensive, antispasmodic, antihistaminic, analgesic, sedative, and antiemetic activity.

phenotype phénotype the observable characteristics of an individual, either in whole or with respect to a single or a few traits, as determined by a combination of the genotype and the environment. Adj.: phenotypic.

phenoxybenzamine phénoxybenzamine an irreversible α-adrenergic blocking agent; the hydrochloride salt is used to control hypertension in pheochromocytoma and to treat urinary symptoms in benign prostatic hyperplasia.

phenpropionate phenpropionate USAN contraction for 3-phenylpropionate.

phentermine phentermine a sympathomimetic amine related to amphetamine, used as an anorectic either as the hydrochloride salt or as the base complexed with an ion exchange resin.

phenyl phényl the monovalent radical C₆H₅sbond, derived from benzene by removal of a hydrogen. Adj.: phenylic.

phenylacetic acid acide phénylacétique a catabolite of phenylalanine, excessively formed and excreted in the urine in phenylketonuria.

phenylalanine (Phe, F) phénylalanine an aromatic essential amino acid necessary for optimal growth in infants and for nitrogen equilibrium in human adults.

phenylbutazone phénylbutazone a nonsteroidal antiinflammatory drug used in the shortterm treatment of severe rheumatoid disorders unresponsive to less toxic agents.

p-phenylenediamine p-phénylènediamine a derivative of benzene used as a dye for hair, garments, and other textiles, as a photographic developing agent, and in a variety of other processes; it is a strong allergen, causing contact dermatitis and bronchial asthma.

phenylephrine phényléphrine an adrenergic used as the hydrochloride salt for its potent vasoconstrictor properties.

phenylketonuria (PKU, PKU1) phénylcétonurie an autosomal recessive disorder marked by inability to convert phenylalanine into tyrosine, so that phenylalanine and its metabolic products accumulate in body fluids; it results in mental retardation, neurologic manifestations, hypopigmentation, eczema, and a mousy odor, all preventable by early restriction of dietary phenylalanine. Adj.: phenylketonuric.

phenylmercuric phénylmercurique denoting a compound containing the radical C₆H₅Hg—, forming various antiseptic, antibacterial, and fungicidal salts; compounds of the acetate and nitrate salts are used as bacteriostatic pharmaceutical preservatives, and the former is used as a herbicide.

phenylpropanolamine phénylpropanolamine an adrenergic, used in the form of the hydrochloride salt as a nasal and sinus decongestant, as an appetite suppressant, and in the treatment of stress incontinence.

phenylpyruvic acid acide phénylpyruvique an intermediary product produced when the normal pathway of phenylalanine catabolism is blocked and excreted in the urine in phenylketonuria.

phenylthiourea phénylthiourée a compound used in genetics research; the ability to taste it is inherited as a dominant trait. It is intensely bitter to about 70 per cent of the population and nearly tasteless to the rest.

phenyltoloxamine phényltoloxamine a sedating antihistamine, used as the citrate salt.

phenytoin phénytoïne an anticonvulsant used in the control of various kinds of epilepsy and of seizures associated with neurosurgery.

pheochrome phéochrome chromaffin.

pheochromoblast phéochromoblaste any of the embryonic structures that develop into chromaffin(pheochrome) cells.

pheochromocyte phéochromocyte chromaffin cell.

pheochromocytoma phéochromocytome a tumor of chromaffin tissue of the adrenal medulla or sympathetic paraganglia; symptoms, notably hypertension, reflect the increased secretion of epinephrine and norepinephrine.

pheresis aphérèse apheresis.

pheromone phéromone a substance secreted to the outside of the body and perceived (as by smell) by other individuals of the same species, releasing specific behavior in the percipient.

PhG PhG Graduate in Pharmacy.

Phialophora Phialophora a genus of imperfect fungi. P. verrucosa is a cause of chromoblastomycosis; P. jeanselmi is a cause of maduromycosis.

-phil -phile word element [Gr.]. one having an affinity for something. Also -phile. Adj.: -philic.

-phile -phile see phil.

-philia -philie word element [Gr.]. affinity for; morbid fondness of. Adj.: -philic.

philtrum philtrum the vertical groove in the median portion of the upper lip.

phimosis phimosis constriction of the orifice of the prepuce so that it cannot be drawn back over the glans. Adj.: phimotic.

phlebangioma phlébangiome a venous aneurysm.

phlebarteriectasia phlébartériectasie general dilatation of veins and arteries.

phlebectasia phlébectasie varicosity (1).

phlebectomy phlébectomie excision of a vein, or a segment of a vein.

phlebemphraxis blocage d’une veine par un bouchon ou un caillot stoppage of a vein by a plug or clot.

phlebitis phlébite inflammation of a vein. Adj.: phlebitic. sinus p. p. sinusale inflammation of a cerebral sinus.

phleb(o)- phléb(o)- word element [Gr.]. vein.

phleboclysis phléboclyse injection of fluid into a vein.

phlebography phlébographie 1. venography; angiography of a vein. 2. the graphic recording of the venous pulse.

phlebolithiasis phlébolithiase the development of calculi in veins.

phlebomanometer phlébomanomètre an instrument for the direct measurement of venous blood pressure.

phlebophlebostomy phlébophlébostomie operative anastomosis of vein to vein.

phleborheography phléborhéographie a technique employing a plethysmograph with cuffs applied to the abdomen, thigh, calf, and foot, for measuring venous volume changes in response to respiration and to compression of the foot or calf.

phleborrhaphy phléborraphie suture of a vein.

phlebosclerosis phlébosclérose fibrous thickening of the walls of veins.

phlebostasis phlébostase 1. venous stasis. 2. temporary sequestration of a portion of blood from the general circulation by compressing the veins of a limb.

phlebothrombosis phlébothrombose the development of venous thrombi in the absence of associated inflammation.

Phlebotomus Phlebotomus a genus of biting sandflies, the females of which suck blood. They are vectors of various diseases, including cutaneous and visceral leishmaniasis, Carrión disease, and phlebotomus fever.

phlebotomy phlébotomie venotomy; incision of a vein.

Phlebovirus Phlebovirus sandfly fever viruses; a genus of the family Bunyaviridae including sandfly fever and Rift Valley fever viruses.

phlegm flegme viscid mucus excreted in abnormally large quantities from the respiratory tract.

phlegmasia phlegmasie [Gr.] inflammation. p. alba dolens phlegmasia alba dolens phlebitis of the femoral vein with swelling of the leg, occasionally following parturition or an acute febrile illness. p. cerulea dolens phlegmasia cerulea dolens an acute fulminating form of deep venous thrombosis, with pronounced edema and severe cyanosis of the limb.

phlegmon phlegmon diffuse inflammation of the soft or connective tissue due to infection. Adj.: phlegmonous.

phlog(o)- phlog(o)- word element [Gr.]. inflammation.

phlogogenic phlogogène producing inflammation.

phlorhizin hydrolase phlorhizine hydrolase glycosylceramidase.

phlyctena phlyctène pl. phlyctenae [Gr.] 1. a small blister made by a burn. 2. a small vesicle containing lymph seen on the conjunctiva in certain conditions. Adj.: phlyctenar.

phlyctenular phlycténulaire associated with the formation of phlyctenules, or of vesicle-like prominences.

phlyctenule phlycténule a minute vesicle; an ulcerated nodule of cornea or conjunctiva.

phobia phobie a persistent, irrational, intense fear of a specific object, activity, or situation (the phobic stimulus), fear that is recognized as being excessive or unreasonable by the individual himself. When a phobia is a significant source of distress or interferes with social functioning, it is considered a mental disorder (sometimes called a phobic disorder); in DSM-IV phobias are classified with the anxiety disorders and are subclassified as agoraphobia, specific phobias, and social phobias. Adj.: phobic. simple p. p. simple specific p. social p. p. sociale an anxiety disorder characterized by fear and avoidance of social or performance situations in which the individual fears possible embarrassment and humiliation. specific p. p. spécifique persistent and excessive or unreasonable fear of a circumscribed, welldefined object or situation.

-phobia -phobie word element [Gr.]. fear of; aversion to.

phocomelia phocomélie congenital absence of the proximal portion of a limb or limbs, the hands or feet being attached to the trunk by a small, irregularly shaped bone. Adj.: phocomelic.

phocomelus phocomèle an individual exhibiting phocomelia.

phonasthenia phonasthénie weakness of the voice; difficult phonation from fatigue.

phonendoscope phonendoscope a stethoscopic device that intensifies auscultatory sounds.

phon(o)- phon(o)- word element [Gr.]. sound; voice; speech.

phonocardiography phonocardiographie the graphic representation of heart sounds or murmurs; by extension, the term also includes pulse tracings (carotid, apex, and jugular pulses). Adj.: phonocardiographic.

phonocatheter phonocathéter a device similar to a conventional catheter, with a microphone at the tip.

phonology phonologie the science of vocal sounds. Adj.: phonological.

phonomyoclonus phonomyoclonie myoclonus in which a sound is heard on auscultation of an affected muscle, indicating fibrillar contractions.

phonomyography phonomyographie the recording of sounds produced by muscle contraction.

phonostethograph phonostéthographe an instrument by which chest sounds are amplified, filtered, and recorded.

phonosurgery phonochirurgie a group of surgical procedures whose purpose is to restore, maintain, or enhance the voice.

phorbol phorbol a polycyclic alcohol occurring in croton oil; it is the parent compound of the phorbol esters. p. ester ester de phorbol any of several esters of phorbol that are potent cocarcinogens, activating a cellular protein kinase; used in research to enhance the induction of mutagenesis or tumors by carcinogens.

-phore -phore word element [Gr.]. a carrier.

-phoresis -phorèse word element [Gr.]. transmission.

phoria phorie heterophoria.

phose phose any subjective visual sensation, as of light or color.

phosgene phosgène a suffocating and highly poisonous gas, carbonyl chloride, COCl₂, which causes rapidly fatal pulmonary edema or pneumonia on inhalation; used in the synthesis of organic compounds and formerly as a war gas.

phosphagen phosphagène any of a group of high-energy compounds, including phosphocreatine, that act as reservoirs of phosphate bond energy, donating phosphoryl groups for ATP synthesis when supplies are low.

phosphatase phosphatase any of a group of enzymes that catalyze the hydrolytic cleavage of inorganic phosphate from esters.

phosphate phosphate any salt or ester of phosphoric acid. Adj.: phosphatic.

phosphatemia phosphatémie an excess of phosphates in the blood.

phosphatidic acid acide phosphatidique any of a group of compounds formed by esterification of three hydroxyl groups of glycerol with two fatty acid groups and one phosphoric acid group; from it are derived the phosphoglycerides.

phosphatidylcholine phosphatidylcholine a phospholipid comprising choline linked to phosphatidic acid; it is a major component of cell membranes and is localized preferentially in the outer surface of the plasma membrane.

phosphaturia phosphaturie 1. excretion of phosphates in the urine. 2. hyperphosphaturia.

phosphene phosphène a sensation of light due to a stimulus other than light rays, e.g., a mechanical stimulus.

phosphocreatine (PC) phosphocréatine the phosphagen of vertebrates, a creatine-phosphoric acid compound occurring in muscle, being an important storage form of high-energy phosphate, the energy source in muscle contraction.

phosphodiesterase phosphodiestérase any of a group of enzymes that catalyze the hydrolytic cleavage of an ester linkage in a phosphoric acid compound containing two such ester linkages.

phosphoenolpyruvate phosphoénolpyruvate a high energy derivative of pyruvate occurring as an intermediate in the Embden-Meyerhof pathway of glucose metabolism, in gluconeogenesis, and in the biosynthesis of some amino acids.

6-phosphofructokinase 6-phosphofructokinase an enzyme catalyzing the phosphorylation of fructose 6-phosphate, a site of regulation in the Embden-Meyerhof pathway of glucose metabolism; deficiency of the muscle isozyme causes glycogen storage disease, type VII.

phosphoglycerate phosphoglycérate an anionic form of phosphoglyceric acid; 2-p. and 3-p. are interconvertible intermediates in the Embden-Meyerhof pathway of glucose metabolism.

phosphoglyceride phosphoglycéride a class of phospholipids, whose parent compound is phosphatidic acid; they consist of a glycerol backbone, two fatty acids, and a phosphorylated alcohol (e.g., choline, ethanolamine, serine, or inositol) and are a major component of cell membranes.

phosphoinositide phosphoïnositide any of a number of phosphorylated inositol-containing compounds that play roles in cell activation and calcium mobilization in response to hormones.

phospholipase phospholipase any of four enzymes (phospholipase A to D) that catalyze the hydrolysis of specific ester bonds in phospholipids.

phospholipid phospholipide any lipid that contains phosphorus, including those with a glycerol backbone (phosphoglycerides and plasmalogens) or a backbone of sphingosine or a related substance (sphingomyelins). They are the major lipids in cell membranes.

phosphonecrosis phosphonécrose phosphorus necrosis.

phosphoprotein phosphoprotéine a conjugated protein in which phosphoric acid is esterified with a hydroxy amino acid.

phosphoric acid acide phosphorique 1. orthophosphoric acid, the monomeric form H₃PO₄. 2. a general term encompassing the monomeric (orthophosphoric acid), dimeric (pyrophosphoric acid), and polymeric (metaphosphoric acid) forms of the acid. Diluted p.a. is used as a pharmaceutical solvent and a gastric acidifier.

phosphorism phosphorisme chronic phosphorus poisoning; see phosphorus.

phosphorolysis phosphorolyse cleavage of a chemical bond with simultaneous addition of the elements of phosphoric acid to the residues.

phosphorous acid acide phosphoreux H₃PO₃; its salts are the phosphites.

phosphorus (P) phosphore chemical element (see Table of Elements), at. no. 15. Ingestion or inhalation produces toothache, phosphonecrosis (phossy jaw), anorexia, weakness, and anemia. Phosphorus is an essential element in the diet; in the form of phosphates, it is a major component of the mineral phase of bone and occurs in all tissues, being involved in almost all metabolic processes. Adj.: phosphorous, phosphoric. p. 32 p. 32 a radioisotope of phosphorus having a half-life of 14.28 days and emitting beta particles (1.71 MeV); therapeutic uses include treatment of polycythemia vera, chronic myelocytic leukemia, chronic lymphocytic leukemia, and certain ovarian and prostate carcinomas, palliation of metastatic skeletal disease, and treatment of intraperitoneal and intrapleural malignant effusions.

phosphorylase phosphorylase 1. any of a group of enzymes that catalyze the phosphorolysis of glycosides, transferring the cleaved glycosyl group to inorganic phosphate. When not qualified with the substrate name, the term usually denotes glycogen phosphorylase (animals) or starch phosphorylase (plants). 2. any of a group of enzymes that catalyze the transfer of a phosphate group to an organic acceptor.

phosphorylase kinase phosphorylase kinase phosphorylase b kinase; an enzyme that catalyzes the phosphorylation and activation of glycogen phosphorylase, a step in the cascade of reactions regulating glycogenolysis.

phosphorylase b kinase deficiency déficience en phosphorylase b kinase an X-linked disorder of glycogen storage due to deficiency of the enzyme in the liver, characterized in affected males by hepatomegaly, occasional fasting hypoglycemia, and some growth retardation.

phosphorylation phosphorylation the metabolic process of introducing a phosphate group into an organic molecule. oxidative p. p. oxydative the formation of high-energy phosphate bonds by phosphorylation of ADP to ATP coupled to the transfer of electrons from reduced coenzymes to molecular oxygen via the electron transport chain; it occurs in the mitochondria. substrate-level p. p. au niveau du substrat the formation of high-energy phosphate bonds by phosphorylation of ADP to ATP (or GDP to GTP) coupled to cleavage of a high-energy metabolic intermediate.

phosphotransferase phosphotransférase any of a subclass of enzymes that catalyze the transfer of a phosphate group.

photalgia photalgie pain, as in the eye, caused by light.

photic photique pertaining to light.

phot(o)- phot(o)- word element [Gr.]. light.

photoablation photoablation volatilization of tissue by ultraviolet radiation emitted by a laser.

photoactive photoactif reacting chemically to sunlight or ultraviolet radiation.

photoaging photo-vieillissement photodamage with premature aging of the skin.

photoallergen photoallergène an agent that elicits an allergic response to light.

photoallergy photo-allergie a delayed immunologic type of photosensitivity involving a chemical substance to which the individual has previously become sensitized, combined with radiant energy. Adj.: photoallergic.

photobiology photobiologie the branch of biology dealing with the effect of light on organisms. Adj.: photobiologic, photobiological.

photobiotic photobiotique living only in the light.

photocatalysis photocatalyse promotion or stimulation of a chemical reaction by light. Adj.: photocatalytic.

photocatalyst photocatalyste a substance, e.g., chlorophyll, that brings about a chemical reaction to light.

photochemistry photochimie the branch of chemistry dealing with the chemical properties or effects of light rays or other radiation. Adj.: photochemical.

photochemotherapy photochimiothérapie treatment by means of drugs (e.g., methoxsalen) that react to ultraviolet radiation or sunlight.

photocoagulation photocoagulation condensation of protein material by the controlled use of an intense beam of light (e.g., argon laser) used especially in the treatment of retinal detachment and destruction of abnormal retinal vessels or intraocular tumor masses.

photodamage photolésion damage to the skin from prolonged exposure to ultraviolet radiation.

photodermatitis photodermatite 1. phototoxic dermatitis. 2. any of the types of dermatitis caused by exposure to ultraviolet radiation, such as that in sunlight.

photodynamic photodynamique powerful in the light; used particularly for the action exerted by fluorescent substances in the light.

photofluorography photofluorographie the photographic recording of fluoroscopic images on small films, using a fast lens.

photogenic photogénique 1. produced by light, as photogenic epilepsy. 2. producing or emitting light.

photoluminescence photoluminescence the quality of being luminescent after exposure to light or other electromagnetic radiation.

photolysis photolyse chemical decomposition or cleavage of a bond by the action of light or other radiant energy. Adj.: photolytic.

photomedicine photomédecine the medical specialty dealing with interactions between light and living systems, such as therapeutic uses such as phototherapy and pathologic effects such as photodermatitis.

photometry photométrie measurement of the intensity of light.

photomicrograph photomicrographie a photograph of an object as seen through an ordinary light microscope.

photon photon a particle (quantum) of radiant energy.

photoparoxysmal photoparoxystique photoconvulsive; denoting an abnormal electroencephalographic response to photic stimulation (brief flashes of light), marked by diffuse paroxysmal discharge recorded as spikewave complexes; the response may be accompanied by minor seizures.

photoperiod photopériode the period of time per day that an organism is exposed to daylight (or to artificial light). Adj.: photoperiodic.

photoperiodism photopériodisme the physiologic and behavioral reactions brought about in organisms by changes in the duration of daylight and darkness.

photopheresis photophérèse a technique for treating cutaneous T-cell lymphoma, in which a photoactive chemical is administered, the blood is removed and circulated through a source of ultraviolet radiation, then returned to the patient; it is believed to stimulate the immune system.

photophilic photophile thriving in light.

photophobia photophobie abnormal visual intolerance to light. Adj.: photophobic.

photophthalmia photophtalmie ophthalmia due to exposure to intense light, as in snow blindness.

photopia photopie day vision. Adj.: photopic.

photopigment photopigment a pigment that is unstable in the presence of light.

photopsia photopsie appearance as of sparks or flashes in retinal irritation.

photopsin photopsine the opsin of the cones of the retina that combines with retinal to form photochemical pigments.

photoptarmosis éternuement provoqué par l’influence de la lumière sneezing caused by the influence of light.

photoptometer photoptomètre an instrument for measuring visual acuity by determining the smallest amount of light that will render an object just visible.

photoreactivation photoréactivation reversal of the biological effects of ultraviolet radiation on cells by subsequent exposure to visible light.

photoreceptor photorécepteur a nerve endorgan or receptor sensitive to light.

photorefractive photoréfractif pertaining to the refraction of light.

photoretinitis photorétinite retinitis due to exposure to intense light.

Photorhabdus Photorhabdus a genus of gram-negative, non-spore-forming, luminescent, motile, rod-shaped bacteria; organisms occur as symbionts of nematodes and as parasites of insects and are opportunistic pathogens for humans.

photoscan scintigramme a two-dimensional representation of gamma rays emitted by a radioactive isotope in body tissue, produced by a printout mechanism utilizing a light source to expose a photographic film.

photosensitivity photosensibilité 1. ability of a cell, organ, or organism to react to light. 2. an abnormal response of the skin or eyes to sunlight. Adj.: photosensitive.

photosensitization photosensibilisation development of abnormally heightened reactivity of the skin or eyes to sunlight.

photostable photostable unchanged by the influence of light.

photosynthesis photosynthèse a chemical combination caused by the action of light; specifically, the formation of carbohydrates from carbon dioxide and water in the chlorophyll tissue of plants under the influence of light. Adj.: photosynthetic.

phototaxis phototaxie the movement of cells and microorganisms in response to light. Adj.: phototactic.

phototherapy photothérapie 1. treatment of disease by exposure to light. 2. photodynamic therapy.

phototoxic phototoxique pertaining to, characterized by, or producing phototoxicity.

phototoxicity phototoxicité a type of photosensitivity that is induced by a toxic substance, as opposed to a photoallergy. Adj.: phototoxic.

phototrophic phototrophe capable of deriving energy from light.

phototropism phototropisme 1. the tendency of an organism to turn or move toward or away from light. 2. color change produced in a substance by the action of light. Adj.: phototropic.

phrenic phrénique 1. diaphragmatic. 2. mental (1).

phrenicocolic phrénicocolique pertaining to or connecting the diaphragm and colon.

phrenitis phrénite diaphragmitis; inflammation of the diaphragm.

phren(o)- phrén(o)- word element [Gr.]. (1) diaphragm; (2) mind; (3) phrenic nerve.

phrenogastric phrénogastrique pertaining to the diaphragm and stomach.

phrenohepatic phrénohépatique pertaining to the diaphragm and liver.

phrenoplegia phrénoplégie paralysis of the diaphragm.

phrenotropic phrénotrope exerting its principal effect upon the mind.

phrynoderma phrynodermie a follicular hyperkeratosis probably due to deficiency of vitamin A or of essential fatty acids.

phthalein phthaléine any one of a series of coloring matters formed by the condensation of phthalic anhydride with the phenols.

phthiriasis phtiriase pediculosis pubis.

Phthirus Phthirus a genus of lice. P. pubis is the pubic or crab louse, which infests the hair of the pubic region, and sometimes the eyebrows and eyelashes.

phthisis phthisie a wasting of the body.

Phycomycetes Phycomycetes a group of fungi comprising common water, leaf, and bread molds; they can cause phycomycosis in humans.

phycomycosis phycomycose 1. any of a group of acute fungal diseases caused by members of Phycomycetes. 2. mucormycosis.

phylogeny phylogenèse the complete developmental history of a group of organisms. Adj.: phylogenic.

phylum embranchement pl. phyla [L.] a primary division of a kingdom, composed of a group of related classes; in the taxonomy of plants and fungi, the term division is used instead. Mycologists sometimes use the word to denote any important group of organisms.

phyma phyma, phyme pl. phymata [Gr.] a skin swelling or tumor larger than a tubercle.

physiatrics physiatrie physiatry.

physiatrist physiatre a physician who specializes in physiatry.

physiatry physiatrie the branch of medicine that deals with the prevention, diagnosis, and treatment of disease or injury, and the rehabilitation from resultant impairments and disabilities, using physical and sometimes pharmaceutical agents.

physical physique pertaining to the body, to material things, or to physics.

physician médecin 1. an authorized practitioner of medicine, as one graduated from a college of medicine or osteopathy and licensed by the appropriate board; see also doctor. 2. one who practices medicine as distinct from surgery. p. assistant m.-assistant one who has been trained in an accredited program and certified by an appropriate board to perform certain of a physician’s duties, including history taking, physical examination, diagnostic tests, treatment, and certain minor surgical procedures, all under the responsible supervision of a licensed physician. Abbreviated P.A. attending p. m. traitant 1. a physician who has admitting privileges at a hospital. 2. the physician with primary responsibility for the care of a patient in a particular case. emergency p. urgentologue a specialist in emergency medicine. family p. m. de famille a medical specialist who plans and provides the comprehensive primary health care of all members of a family, regardless of age or sex, on a continuous basis. resident p. m. interne a graduate and licensed physician receiving training in a specialty, usually in a hospital.

physicochemical physicochimique pertaining to both physics and chemistry.

physics physique the study of the laws and phenomena of nature, especially of forces and general properties of matter and energy.

physi(o)- physi(o)- word element [Gr.]. nature; physiology; physical.

physiochemical physiochimique pertaining to both physiology and chemistry. physiognomy physiognomonie 1. determination of mental or moral character and qualities by the face. 2. physionomie the countenance, or face. 3. the facial expression and appearance as a means of diagnosis.

physiologic physiologique physiological.

physiological physiologique pertaining to physiology; normal; not pathologic.

physiologist physiologiste a specialist in physiology.

physiology physiologie 1. the science of the functions of the living organism and its parts, and of the physical and chemical factors and processes involved. 2. the basic processes underlying the functioning of a species or class of organism, or any of its parts or processes. morbid p., pathologic p. p. morbide the study of disordered function or of function in diseased tissues.

physiopathologic physiopathologique pertaining to pathologic physiology.

physiotherapist physiothérapeute physical therapist.

physiotherapy physiothérapie physical therapy.

physique physique the body organization, development, and structure.

phys(o)- phys(o)- word element [Gr.]. air; gas.

physohematometra physohématomètre gas and blood in the uterine cavity.

physohydrometra présence de gaz et de sérum dans la cavité utérine gas and serum in the uterine cavity.

physometra physomètre gas in the uterine cavity.

physostigmine physostigmine a cholinergic alkaloid usually obtained from dried ripe seed of Physostigma venenosum (Calabar bean), used as a topical miotic and to reverse the central nervous system effects of an overdosage of anticholinergic drugs; used in the form of the salicylate and sulfate salts.

phytanic acid acide phytanique a 20-carbon branched-chain fatty acid occurring at high levels in dairy products and the fat of ruminants and accumulated in the tissues in Refsum disease.

phytic acid acide phytique the hexaphosphoric acid ester of inositol, found in many plants and microorganisms and in animal tissues.

phyt(o)- phyt(o)- word element [Gr.]. plant; an organism of the vegetable kingdom.

phytobezoar phytobézoard a bezoar composed of vegetable fibers.

phytoestrogen phytoestrogène any of a group of weakly estrogenic, nonsteroidal compounds widely occurring in plants.

phytohemagglutinin phytohémagglutinine a hemagglutinin of plant origin.

phytomedicine 1. phytomédicament a preparation of a medicinal herb. 2. phytothérapie herbalism.

phytonadione phytonadione vitamin K₁: a vitamin found in green plants or prepared synthetically, used as a prothrombinogenic agent.

phytoparasite phytoparasite any parasitic vegetable organism or species.

phytopathogenic phytopathogène producing disease in plants.

phytopathology phytopathologie the pathology of plants.

phytophotodermatitis phytophotodermatite phototoxic dermatitis induced by exposure to certain plants and then to sunlight.

phytoprecipitin phytoprécipitine a precipitin formed in response to vegetable antigen.

phytosis phytose any disease caused by a phytoparasite.

phytotherapy phytothérapie treatment by use of plants.

phytotoxic phytotoxique 1. pertaining to phytotoxin. 2. poisonous to plants.

phytotoxin phytotoxine an exotoxin produced by certain species of higher plants; any toxin of plant origin.

pia-arachnitis pie-arachnite leptomeningitis.

pia-arachnoid pie-arachnoïde the pia mater and arachnoid considered together as one functional unit; the leptomeninges.

pia-glia membrane constituant l’une des couches de la pie-arachnoïde a membrane constituting one of the layers of the pia-arachnoid.

pial pie-mérien pertaining to the pia mater.

pia mater pie-mère [L.] the innermost of the three meninges covering the brain and spinal cord.

piarachnoid pie-arachnoïde pia-arachnoid.

pica pica [L.] compulsive eating of nonnutritive substances, such as ice, dirt, flaking paint, clay, hair, or laundry starch.

pico- pico- word element [It.] designating one trillionth (10^{− 12}) part of the unit to which it is joined. Symbol p.

picogram (pg) picogramme one-trillionth (10^{− 12}) of a gram.

picornavirus picornavirus an extremely small, ether-resistant RNA virus, one of the group comprising the enteroviruses and the rhinoviruses.

picrate picrate any salt of picric acid.

picric acid acide picrique trinitrophenol.

picr(o)- picr(o)- word element [Gr.]. 1. bitter. 2. related to picric acid.

picrocarmine picrocarmin a histological stain consisting of a mixture of carmine, ammonia, distilled water, and aqueous solution of picric acid.

PID PID pelvic inflammatory disease.

piebaldism piébaldisme a congenital, autosomal dominant type of hypomelanosis characterized by patchy areas of lightened or white skin, often associated with a white forelock.

piedra piedra a fungal disease of the hair in which white or black nodules of fungi form on the shafts.

piesesthesia baresthésie the sense by which pressure stimuli are felt.

piesimeter piézomètre instrument for testing the sensitiveness of the skin to pressure.

-piesis -piézo word element [Gr.]. pressure. Adj.: -piesic.

pigment pigment 1. any coloring matter of the body. 2. a stain or dyestuff. 3. a paintlike medicinal preparation to be applied to the skin. Adj.: pigmentary. bile p. p. biliaire any of the coloring matters of the bile, including bilirubin, biliverdin, etc. blood p., hematogenous p. p. sanguin any of the pigments derived from hemoglobin. respiratory p’s p. respiratoires substances, e.g., hemoglobin, myoglobin, or cytochromes, which take part in the oxidative processes of the animal body. retinal p’s, visual p’s p. rétiniens the photopigments in retinal rods and cones that respond to certain colors of light and initiate the process of vision.

pigmentation pigmentation the deposition of coloring matter; the coloration or discoloration of a part by a pigment.

pigmented pigmenté colored by deposit of pigment.

pilar pileux hairy.

pile 1. hémorroïde hemorrhoid. 2. pile an aggregation of similar elements for generating electricity. sentinel p. h. sentinelle a hemorrhoid-like thickening of the mucous membrane at the lower end of an anal fissure.

pili pili [L.] genitive and plural of pilus.

piliferous pilifère bearing or producing hair.

pill comprimé tablet.

pillar pilier a supporting column, usually occurring in pairs. articular p’s p. articulaires columnlike structures formed by the articulation of the superior and inferior articular processes of the vertebrae. p’s of fauces arcs du voile du palais the palatoglossal arch and palatopharyngeal arch considered together.

pil(o)- pil(o)- word element [L.]. hair; composed of hair.

pilocarpine pilocarpine a cholinergic alkaloid, used as the base or the hydrochloride or nitrate salt as an antiglaucoma agent and miotic and as the hydrochloride salt in the treatment of xerostomia associated with radiotherapy or Sjögren syndrome.

pilocystic pilokystique hollow or cystlike, and containing hair; said of dermoid cysts.

piloerection horripilation horripilation.

piloleiomyoma piloléiomyome a cutaneous leiomyoma that arises from the arrectores pilorum muscles.

pilomatricoma pilomatricome a solitary, benign, calcifying adnexal tumor of hair follicle origin, appearing as a circumscribed, firm, intracutaneous nodule, usually on the face or upper body.

pilomatrixoma pilomatrixome pilomatricoma.

pilomotor pilomoteur pertaining to the arrector pili muscles and horripilation.

pilonidal pilonidal having a nidus of hairs.

pilosebaceous pilosébacé pertaining to the hair follicles and the sebaceous glands.

pilus pl. pili [L.] 1. poil a hair. Adj.: pilial. 2. cil one of the minute filamentous appendages of certain bacteria, associated with antigenic properties and sex functions of the cell. Adj.: piliate. pili incarnati p. incarnati a condition characterized by ingrown hairs. pili torti p. torti a condition characterized by twisted hairs.

pimelopterygium ptérygion sébacé a fatty outgrowth on the conjunctiva.

pimozide pimozide an antipsychotic and antidyskinetic agent used in the treatment of Gilles de la Tourette syndrome.

pimple bouton a papule or pustule.

pin broche a slender, elongated piece of metal used for securing fixation of parts. Steinmann p. b. de Steinmann a metal rod for the internal fixation of fractures.

pindolol pindolol a nonselective beta-adrenergic blocking agent with intrinsic sympathomimetic activity; used in the treatment of hypertension.

pineal pinéal 1. pertaining to the pineal body. 2. shaped like a pine cone.

pinealectomy pinéalectomie excision of the pineal body.

pinealism pinéalisme the condition due to deranged secretion of the pineal body.

pinealoblastoma pinéaloblastome pinealoma in which the pineal cells are not well differentiated.

pinealocyte pinéalocyte an epithelioid cell of the pineal body.

pinealoma pinéalome a tumor of the pineal body composed of neoplastic nests of large epithelial cells; it may cause hydrocephalus, precocious puberty, and gait disturbances.

pinguecula pinguécula pl. pingueculae [L.] a benign yellowish spot on the bulbar conjunctiva.

piniform piniforme conical or cone shaped.

pinkeye œil rose acute contagious conjunctivitis.

pinna auricule auricle (1). Adj.: pinnal.

pinocyte pinocyte a cell that exhibits pinocytosis. Adj.: pinocytic.

pinocytosis pinocytose the cellular uptake of extracellular fluid and its contents by the formation of invaginations by the cell membrane, which pinch off to form fluid-filled vesicles in the cytoplasm. Adj.: pinocytotic.

pinosome pinosome the intracellular vacuole formed by pinocytosis.

pint pinte a unit of liquid measure; in the United States it is 16 fluid ounces (0.473 liter). In Great Britain, it is the imperial pint, equal to 20 fluid ounces (0.568 liter).

pinta pinta a treponemal infection of tropical America, characterized by bizarre pigmentary changes in the skin.

pinworm oxyure oxyurid.

pioglitazone pioglitazone an antidiabetic agent that decreases insulin resistance in the peripheral tissues and liver; used as the hydrochloride salt in the treatment of type 2 diabetes mellitus.

pipecolic acid acide pipécolique a cyclic amino acid occurring as an intermediate in a minor pathway of lysine degradation and at elevated levels in the blood in cerebrohepatorenal syndrome and in hyperlysinemia.

pipecuronium pipécuronium a nondepolarizing neuromuscular blocking agent used as the bromide salt as an adjunct to anesthesia, inducing skeletal muscle relaxation.

piperacillin pipéracilline a semisynthetic broad-spectrum penicillin effective against a wide variety of gram-positiveand gram-negative bacteria; used as the sodium salt.

piperazine pipérazine an anthelmintic used against Ascaris lumbricoides and Enterobius vermicularis; used as the citrate salt.

pipet pipette pipette.

pipette [Fr.] 1. pipette a glass or transparent plastic tube used in measuring or transferring small quantities of liquid or gas. 2. pipeter to dispense by means of a pipette.

pirbuterol pirbutérol a β₂-adrenergic receptor agonist, used in the form of the acetate ester as a bronchodilator.

piriform piriforme pear-shaped.

Piroplasma Piroplasma Babesia.

piroplasmosis piroplasmose babesiasis.

piroxicam piroxicam a nonsteroidal antiinflammatory drug used in the treatment of various rheumatic disorders and dysmenorrhea.

pisiform pisiforme resembling a pea in shape and size.

PIT PIT plasma iron turnover.

pit 1. creux, cavité a fovea or indentation, either normal or abnormal. 2. cicatrice varioliforme pockmark. 3. comprimer, prendre le godet to indent, or to become and remain for a few minutes indented, by pressure. anal p. anus proctodeum. auditory p. trou auditif a depression on the auditory placode, marking the beginning of embryonic development of the internal ear. coated p’s fossettes tapissées small protein-coated pits in the plasma membrane of many cells, involved in receptor-mediated endocytosis. ear p. tragus preauricular p. lens p. fossette cristallinienne a pitlike depression in the ectoderm of the lens placode where the primordial lens is developing. olfactory p. crypte sensorielle the primordium of a nasal cavity. otic p. trou otique auditory p. preauricular p. f. préauriculaire a small depression anterior to the helix of the ear, sometimes leading to a fistula or congenital preauricular cyst. p. of stomach c. épigastrique epigastrium.

pitch brai 1. a dark viscous residue from distillation of tar and other substances. 2. any of various bituminous substances such as natural asphalt. 3. poix a resin from the sap of some coniferous trees. 4. tonie the quality of sound dependent principally on its frequency.

pithecoid pithécoïde apelike.

pitta pitta [Sanskrit] in ayurveda, one of the three doshas, condensed from the elements fire and water. It is the principle of transformation energy and governs heat and metabolism in the body, is concerned with the digestive, enzymatic, and endocrine systems, and is eliminated from the body through sweat.

pitting 1. érosion the formation, usually by scarring, of a small depression. 2. pitting the removal from erythrocytes, by the spleen, of such structures as iron granules, without destruction of the cells. 3. prenant le godet remaining indented for a few minutes after removal of firm finger pressure, distinguishing fluid edema from myxedema.

pituicyte pituicyte the distinctive fusiform cell composing most of the neurohypophysis.

pituitarism pituitarisme disorder of pituitary function; see hyper- and hypopituitarism.

pituitary pituitaire 1. hypophysial. 2. pituitary gland; see under gland. anterior p. hypophyse antérieure adenohypophysis. posterior p. hypophyse postérieure neurohypophysis.

pityriasis pityriasis any of various skin diseases characterized by fine, branny scales. p. alba p. alba a chronic type with patchy scaling and hypopigmentation of the skin of the face. p. lichenoides p. lichenoides a rare self-limited type with discolored papular lesions and sometimes ulceration; there are both acute and chronic forms. p. rosea p. rosé de Gibert a type marked by scaling, pink, oval macules arranged with the long axes parallel to the cleavage lines of the skin. p. rubra pilaris p. rubra pilaire a chronic inflammatory type marked by pink scaling macules and horny follicular papules; it usually begins with seborrhea of the scalp and face and then progresses to keratoderma of palms and soles. p. versicolor p. versicolor tinea versicolor.

pityroid pityroïde furfuraceous; branny.

Pityrosporum Pityrosporum former name for Malassezia.

pivalate pivalate USAN contraction for trimethylacetate.

pK_a pK_a the negative logarithm of the ionization constant (K) of an acid, the pH of a solution in which half of the acid molecules are ionized.

PKU, PKU1 PCU phenylketonuria.

placebo placebo [L.] any dummy medical treatment; originally, a medicinal preparation having no specific pharmacological activity against the patient’s illness or complaint given solely for the psychophysiological effects of the treatment; more recently, a dummy treatment administered to the control group in a controlled clinical trial in order that the specific and nonspecific effects of the experimental treatment can be distinguished.

placenta placenta pl. placentas, placentae [L.] an organ characteristic of true mammals during pregnancy, joining mother and fetus, providing endocrine secretion and selective exchange of soluble bloodborne substances through apposition of uterine and trophoblastic vascularized parts. Adj.: placental. p. accreta p. accreta one abnormally adherent to the myometrium, with partial or complete absence of the decidua basalis. circumvallate p. p. circumvallate one in which a dense peripheral ring is raised from the surface and the attached membranes are doubled back over the placental edge. deciduate p., deciduous p. p. décidual a placenta or type of placentation in which the decidua or maternal parts of the placenta separate from the uterus and are cast off together with the trophoblastic parts. fetal p. p. fœtal the part of the placenta derived from the chorionic sac that encloses the embryo, consisting of a chorionic plate and villi. hemochorial p. p. hémochorial one in which maternal blood comes in direct contact with the chorion, as in humans. p. increta p. increta placenta accreta with penetration of the myometrium. maternal p. p. maternel the maternally contributed part of the placenta, derived from the decidua basalis. p. membranacea p. membraneux one that is abnormally thin and spread out over an unusually large area of the uterine wall. p. percreta p. percreta placenta accreta with invasion of the myometrium to its peritoneal covering, sometimes causing rupture of the uterus. p. previa p. previa one located in the lower uterine segment, so that it partially or completely covers or adjoins the internal os. p. spuria p. spuria an accessory portion having no blood vessel attachment to the main placenta. p. succenturiata, succenturiate p. p. succenturié an accessory portion attached to the main placenta by an artery or vein. villous p. p. villeux one characterized by the presence of villi that are outgrowths of the chorion.

placentation placentation the series of events following implantation of the embryo and leading to development of the placenta.

placentitis placentite inflammation of the placenta.

placentography placentographie radiological visualization of the placenta after injection of a contrast medium.

placentoid placentoïde resembling the placenta.

placode placode a platelike structure, especially a thickened plate of ectoderm in the early embryo, from which a sense organ develops, e.g., otic p. (ear), lens p. (eye), and nasal p. (nose).

plagiocephaly plagiocéphalie an asymmetric condition of the head, due to irregular closure of the cranial sutures. Adj.: plagiocephalic.

plague peste a severe acute or chronic infectious disease due to Yersinia pestis, beginning with chills and fever, quickly followed by prostration, often with delirium, headache, vomiting, and diarrhea; primarily a disease of rats and other rodents, it is transmitted to humans by flea bites, or communicated from patient to patient. bubonic p. p. bubonique plague with swelling of the lymph nodes, which form buboes in the femoral, inguinal, axillary, and cervical regions; in the severe form, septicemia occurs, producing petechial hemorrhages. pneumonic p., pulmonic p. p. pulmonaire a rapidly progressive, highly contagious pneumonia with extensive involvement of the lungs and productive cough with mucoid, bloody, foamy, plague bacilli-laden sputum. sylvatic p. p. sylvatique plague in wild rodents, such as the ground squirrel, which serve as a reservoir from which humans may be infected.

planar 1. planaire flat. 2. plan of or pertaining to a plane.

plane plan 1. a flat surface determined by the position of three points in space. 2. a specified level, as the plane of anesthesia. 3. aplanir to rub away or abrade; see planing. 4. a superficial incision in the wall of a cavity or between tissue layers, especially in plastic surgery, made so that the precise point of entry into the cavity or between the layers can be determined. axial p. p. axial one parallel with the long axis of a structure. base p. p. basal an imaginary plane upon which is estimated the retention of an artificial denture. coronal p’s p. frontaux frontal p’s. Frankfort horizontal p. p. orbito-auditif a horizontal plane represented in profile by a line between the lowest point on the margin of the orbit and the highest point on the margin of the auditory meatus. frontal p’s p. frontaux those passing longitudinally through the body from side to side, at right angles to the median plane, dividing the body into front and back parts. horizontal p. p. horizontal 1. one passing through the body, at right angles to both the frontal and median planes, dividing the body into upper and lower parts. 2. one passing through a tooth at right angles to its long axis. median p. p. moyen one passing longitudinally through the middle of the body from front to back, dividing it into right and left halves. nuchal p. p. nucal the outer surface of the occipital bone between the foramen magnum and the superior nuchal line. occipital p. p. occipital the outer surface of the occipital bone above the superior nuchal line. orbital p. p. orbitaire 1. the orbital surface of the maxilla. 2. visual p. sagittal p’s p. sagittaux vertical planes passing through the body parallel to the median plane (or to the sagittal suture), dividing the body into left and right portions. temporal p. p. temporal the depressed area on the side of the skull below the inferior temporal line. transverse p. p. transversal one passing horizontally through the body, at right angles to the sagittal and frontal planes, and dividing the body into upper and lower portions. vertical p. p. vertical one perpendicular to a horizontal plane, dividing the body into left and right, or front and back portions. visual p. p. visuel one passing through the visual axes of the two eyes.

planigraphy planigraphie tomography. Adj.: planigraphic.

planing aplanissement abrasion of disfigured skin to promote epithelialization with minimal scarring; a mechanical method is dermabrasion and a chemical method is chemabrasion.

planning planification consciously setting forth a scheme to achieve a desired end or goal. natural family p. p. familiale naturelle rhythm method.

planocellular planocellulaire composed of flat cells.

planoconcave plan-concave flat on one side and concave on the other.

planoconvex plan-convexe flat on one side and convex on the other.

planta plante the sole of the foot.

plant plante any multicellular eukaryotic organism that performs photosynthesis to obtain its nutrition; plants comprise one of the five kingdoms in the most widely used classification of living organisms.

Plantago Plantago a genus of herbs, including P. indica, P. psyllium (Spanish psyllium), and P. ovata (blond psyllium); see also psyllium.

plantalgia plantalgie pain in the sole of the foot.

plantar plantaire pertaining to the sole of the foot.

plantaris plantaire [L.] plantar.

plantigrade plantigrade walking on the full sole of the foot.

planula 1. planula a larval coelenterate. 2. planulaire something resembling such an animal.

planum planum pl. plana [L.] plane.

plaque plaque 1. any patch or flat area. 2. a superficial, solid, elevated skin lesion. attachment p’s p. d’attache small regions of increased density along the sarcolemma of skeletal muscles to which myofilaments seem to attach. bacterial p., dental p. p. bactérienne a soft thin film of food debris, mucin, and dead epithelial cells on the teeth, providing the medium for bacterial growth. It contains calcium, phosphorus, and other salts, polysaccharides, proteins, carbohydrates, and lipids, and plays a role in the development of caries, dental calculus, and periodontal and gingival diseases. fibrous p. p. fibreuse the lesion of atherosclerosis, a pearly white area within an artery that causes the intimal surface to bulge into the lumen; it is composed of lipid, cell debris, smooth muscle cells, collagen, and, in older persons, calcium. Hollenhorst p’s p. de Hollenhorst atheromatous emboli containing cholesterol crystals in the retinal arterioles, a sign of impending serious cardiovascular disease. senile p’s p. séniles microscopic argyrophilic masses composed of fragmented axon terminals and dendrites surrounding a core of amyloid, seen in small amounts in the cerebral cortex of healthy elderly people and in larger amounts in those with Alzheimer disease.

-plasia -plasie word element [Gr.]. development; formation.

plasm plasme 1. plasma. 2. formative substance (cytoplasm, hyaloplasm, etc.).

plasma plasma 1. blood plasma; the fluid portion of the blood in which the particulate components are suspended. 2. the fluid portion of the lymph. Adj.: plasmatic. antihemophilic human p. p. antihémophilique humain human plasma which has been processed promptly to preserve the antihemophilic properties of the original blood; used for temporary correction of bleeding tendency in hemophilia. blood p. p. sanguin plasma (1). citrated p. p. citraté blood plasma treated with sodium citrate, which prevents clotting. seminal p. p. séminal the fluid portion of the semen, in which the spermatozoa are suspended.

plasmablast plasmoblaste the immature precursor of a plasma cell.

plasmacyte plasmocyte plasma cell. Adj.: plasmacytic.

plasmacytoma plasmocytome 1. plasma cell dyscrasias. 2. solitary myeloma.

plasmacytosis plasmocytose an excess of plasma cells in the blood.

plasmalemma plasmalemme 1. plasma membrane. 2. a thin peripheral layer of the ectoplasm in a fertilized egg.

plasmalogen plasmalogène any of various phospholipids in which the group at one C1 of glycerol is an ether-linked alcohol in place of an ester-linked fatty acid, found in myelin sheaths of nerve fibers, cell membranes of muscle, and platelets.

plasmapheresis plasmaphérèse the removal of plasma from withdrawn blood, with retransfusion of the formed elements into the donor; generally, type-specific fresh frozen plasma or albumin is used to replace the withdrawn plasma. The procedure may be done for purposes of collecting plasma components or for therapeutic purposes.

plasmid plasmide an extrachromosomal self- replicating structure of bacterial cells that carries genes for a variety of functions not essential for cell growth and that can be transferred to other cells by conjugation or transduction. See also episome. F p. p. F a conjugative plasmid found in F⁺ (male) bacterial cells that leads with high frequency to its transfer, and much less often to transfer of the bacterial chromosome, to an F⁻ (female) cell lacking such a plasmid. R p., resistance p. p. R, p. de résistance a conjugative factor in bacterial cells that promotes resistance to agents such as antibiotics, metal ions, ultraviolet radiation, and bacteriophages.

plasmin plasmine an endopeptidase occurring in plasma as plasminogen, which is activated via cleavage by plasminogen activators; it solubilizes fibrin clots, degrades other coagulationrelated proteins, and can be activated for use in therapeutic thrombolysis.

plasminogen plasminogène the inactive precursor of plasmin, occurring in plasma and converted to plasmin by the action of urokinase.

plasminogen activator activateur du plasminogène see under activator.

plasmocyte plasmocyte plasma cell.

plasmodicidal plasmodicide destructive to plasmodia.

Plasmodium Plasmodium a genus of sporozoa parasitic in the red blood cells of humans and other animals. Four species, P. falciparum, P. malariae, P. ovale, and P. vivax, cause the four specific types of malaria in humans.

plasmodium pl. plasmodia 1. plasmodium, plasmodie a parasite of the genus Plasmodium. 2. plasmodium a multinucleate continuous mass of protoplasm formed by aggregation and fusion of myxamebae. Adj.: plasmodial.

plasmolysis plasmolyse contraction of cell protoplasm due to loss of water by osmosis. Adj.: plasmolytic.

plaster plâtre 1. a gypsum material that hardens when mixed with water, used for immobilizing or making impressions of body parts. 2. a pastelike mixture that can be spread over the skin and that is adhesive at body temperature; varied uses include skin protectant and counterirritant. p. of Paris p. de Paris calcined calcium sulfate; on addition of water it forms a porous mass that is used in making casts and bandages to support or immobilize body parts, and in dentistry for making study models.

plastic plastique 1. tending to build up tissues to restore a lost part. 2. capable of being molded. 3. a high-molecular-weight polymeric material, usually organic, capable of being molded, extruded, drawn, or otherwise shaped and hardened into a form. 4. material that can be molded.

-plasty -plastie word element [Gr.]. formation or plastic repair of.

plate 1. plaque, lame a flat structure or layer, as a thin layer of bone. 2. plaque dental p. 3. couler to apply a culture medium to a Petri dish. 4. ensemencer to inoculate such a plate with bacteria. bite p. p. d’occlusion biteplate. bone p. l. osseuse a metal bar with perforations for the insertion of screws, used to immobilize fractured segments. cribriform p. fascia cribriformis, plaque criblée fascia cribrosa. dental p. p. vissée a plate of acrylic resin, metal, or other material, which is fitted to the shape of the mouth and serves to support artificial teeth. dorsal p. p. dorsale roof p. epiphyseal p. p. épiphysaire see under disk. equatorial p. p. équatoriale the collection of chromosomes at the equator of the cell during metaphase. floor p. p. de plancher the unpaired ventral longitudinal zone of the neural tube. foot p. 1. p. d’appui pour le pied see footplate. 2. bourgeon du membre inférieur the embryonic precursor of a foot. growth p. c. de conjugaison epiphyseal disk. hand p. bourgeon du membre supérieur a flattened expansion at the end of the embryonic limb; the precursor of the hand. medullary p. p. médullaire neural p. motor end p. p. motrice end plate. muscle p. p. musculaire myotome (2). nail p. tablette unguéale nail (1). neural p. p. neurale the thickened plate of ectoderm in the embryo that develops into the neural tube. roof p. p. du toit the unpaired dorsal longitudinal zone of the neural tube. tarsal p. tarse palpébral tarsus (2). tympanic p. p. tympanique the bony plate forming the floor and sides of the meatus auditorius. ventral p. p. ventrale floor p.

platelet plaquette thrombocyte; a disk-shaped structure, 2 to 4 μm in diameter, found in the blood of mammals and important for its role in blood coagulation; platelets, which are formed by detachment of part of the cytoplasm of a megakaryocyte, lack a nucleus and DNA but contain active enzymes and mitochondria.

plateletpheresis thrombaphérèse thrombocytapheresis.

platinum (Pt) platine chemical element (see Table of Elements), at. no. 78.

platy- platy- word element [Gr.]. flat.