| PL | <abbreviation> Placental lactogen. (05 Mar 2000) |
|---|---|
| PL7a receptor-tyrosine kinase | <enzyme> A member of the eph receptor tyrosine kinase subfamily; shows 80% identity with myk-1; genbank l43622 Registry number: EC 2.7.1.- Synonym: pl7a protein (26 Jun 1999) |
| pla | An application to the FDA for approval to market a biologic in the U.S. The FDA determines if a protein pharmaceutical is considered a biologic or a drug, and whether a PLA or an NDA, respectively, should be filed to obtain marketing approval. (14 Nov 1997) |
| Pla protease | <enzyme> Surface protease from a plasmid of yersinia pestis with plasminogen activator and coagulase activities; required for high virulence Registry number: EC 3.4.21.- Synonym: pla gene product, pla protein, yersinia pestis (26 Jun 1999) |
| placard | 1. A public proclamation; a manifesto or edict issued by authority. "All placards or edicts are published in his name." (Howell) 2. Permission given by authority; a license; as, to give a placard to do something. 3. A written or printed paper, as an advertisement or a declaration, posted, or to be posted, in a public place; a poster. 4. An extra plate on the lower part of the breastplate or backplate. 5. [Cf. Placket] A kind of stomacher, often adorned with jewels, worn in the fifteenth century and later. Origin: F, fr. Plaquer to lay or clap on, plaque plate, tablet; probably from Dutch, cf. D. Plakken to paste, post up, plak a flat piece of wood. Source: Websters Dictionary (01 Mar 1998) |
| place | 1. To assign a place to; to put in a particular spot or place, or in a certain relative position; to direct to a particular place; to fix; to settle; to locate; as, to place a book on a shelf; to place balls in tennis. "Upon my head they placed a fruitless crown." (Shak) 2. To put or set in a particular rank, office, or position; to surround with particular circumstances or relations in life; to appoint to certain station or condition of life; as, in whatever sphere one is placed. "Place such over them to be rulers." (Ex. Xviii. 21) 3. To put out at interest; to invest; to loan; as, to place money in a bank. 4. To set; to fix; to repose; as, to place confidence in a friend. "My resolution 's placed." 5. To attribute; to ascribe; to set down. "Place it for her chief virtue." (Shak) To place (a person), to identify him. Synonym: See Put. Origin: Cf. F. Placer. See Place. 1. Any portion of space regarded as measured off or distinct from all other space, or appropriated to some definite object or use; position; ground; site; spot; rarely, unbounded space. "Here is the place appointed." (Shak) "What place can be for us Within heaven's bound?" (Milton) "The word place has sometimes a more confused sense, and stands for that space which any body takes up; and so the universe is a place." (Locke) 2. A broad way in a city; an open space; an area; a court or short part of a street open only at one end. "Hangman boys in the market place." 3. A position which is occupied and held; a dwelling; a mansion; a village, town, or city; a fortified town or post; a stronghold; a region or country. "Are you native of this place?" (Shak) 4. Rank; degree; grade; order of priority, advancement, dignity, or importance; especially, social rank or position; condition; also, official station; occupation; calling. "The enervating magic of place." "Men in great place are thrice servants." (Bacon) "I know my place as I would they should do theirs." (Shak) 5. Vacated or relinquished space; room; stead (the departure or removal of another being or thing being implied). "In place of Lord Bassanio." 6. A definite position or passage of a document. "The place of the scripture which he read was this." (Acts viii. 32) 7. Ordinal relation; position in the order of proceeding; as, he said in the first place. 8. Reception; effect; implying the making room for. "My word hath no place in you." (John viii. 37) 9. <astronomy> Position in the heavens, as of a heavenly body; usually defined by its right ascension and declination, or by its latitude and longitude. <mathematics> Place of arms, the act of kicking the ball after it has been placed on the ground. Place name, the name of a place or locality. To give place, to make room; to yield; to give way; to give advantage. "Neither give place to the devil." . "Let all the rest give place." . To have place, to have a station, room, or seat; as, such desires can have no place in a good heart. To take place. To come to pass; to occur; as, the ceremony will not take place. To take precedence or priority. To take effect; to prevail. "If your doctrine takes place." . "But none of these excuses would take place." . To take the place of, to be substituted for. Synonym: Situation, seat, abode, position, locality, location, site, spot, office, employment, charge, function, trust, ground, room, stead. Origin: F, fr. L. Platea a street, an area, a courtyard, from Gr. Platei^a a street, properly fem. Of platys, flat, broad; akin to Skr. Prithu, Lith. Platus. Cf. Flawn, Piazza, Plate, Plaza. Source: Websters Dictionary (01 Mar 1998) |
| place theory | A theory of pitch perception which states that the perception of the pitch of a sound depends upon the level or region of the basilar membrane of the cochlea which is set into vibration by the sound waves. See: resonance theory of hearing. (05 Mar 2000) |
| placebo | <pharmacology> Any dummy medical treatment, originally, a medicinal preparation having no specific pharmacological activity against the patients 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 non-specific effects of the experimental treatment can be distinguished i.e., the experimental treatment must produce better results than the placebo in order to be considered effective. (18 Nov 1997) |
| placebo effect | An effect usually, but not necessarily, beneficial that is attributable to an expectation that the regimen will have an effect, i.e., the effect is due to the power of suggestion. (12 Dec 1998) |
| placebos | Any dummy medication or treatment. Although placebos originally were medicinal preparations having no specific pharmacological activity against a targeted condition, the concept has been extended to include treatments or procedures, especially those administered to control groups in clinical trials in order to provide baseline measurements for the experimental protocol. (12 Dec 1998) |
| placenta | <anatomy, obstetrics> An organ characteristic of true mammals during pregnancy, joining mother and offspring, providing endocrine secretion and selective exchange of soluble, but not particulate, blood borne substances through an apposition of uterine and trophoblastic vascularised parts. According to species, the area of vascular apposition may be diffuse, cotyledonary, zonary or discoid, the nature of apposition may be labyrinthine or villous, the intimacy of apposition may vary according to what layers are lost of those originally interposed between maternal and foetal blood (maternal endothelium, uterine connective tissue, uterine epithelium, chorion, extraembryonic mesoderm and endothelium of villous capillary). The chorion may be joined by and receive blood vessels from either the yolk sac or the allantois and the uterine lining may be largely shed with the chorion at birth (deciduate) or may separate from the chorion and remain (nondeciduate). The human placenta is discoid, villous, haemochorial, chorioallantoic and deciduate. After birth, it weighs about 600 gm. And is about 16 cm. In diameter and 2 cm. Thick, discounting a principal functional part, the maternal blood in the intervillous space (which leaks out at birth) into which the chorionic villi dip. The villi are grouped into adjoining cotyledons making about 20 velvety bumps on the side of the placenta facing outward to the uterus, the inner side of the placenta facing the foetus is smooth, being covered with amnion, a thin avascular layer that continues past the edges of the placenta to line the entire hollow sphere of chorion except where it is reflected to cover the umbilical cord, which joins foetus and placenta. The cord usually joins the placenta near the centre but may insert at the edge, on the nonplacental chorion or on an accessory placenta. (31 Dec 1997) |
| placenta accreta | Abnormal adherence of part or all of the placenta to the uterine wall, with partial or complete absence of the decidua basalis, especially of the spongiosum layer. (12 Dec 1998) |
| placenta accreta vera | The term applied when villi are juxtaposed to the myometrium. (05 Mar 2000) |
| placenta biloba | A placenta duplex in which the two parts are separated by a constriction. Synonym: placenta bipartita. (05 Mar 2000) |
| placenta bipartita | A placenta duplex in which the two parts are separated by a constriction. Synonym: placenta bipartita. (05 Mar 2000) |