| porin | <protein> Transmembrane matrix proteins (37 kD) found in the outer membranes of gram-positive bacteria. Associate as trimers to form channels (1 nm diameter, ca 10exp5 per bacterium) through which hydrophilic molecules of up to 600D can pass. Similar porins are also found in outer mitochondrial membranes (VDAC, voltage dependent anion selective channel). (14 Oct 1997) |
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| porins | Protein molecules situated in the outer membrane of bacteria that, in dimeric or trimeric form, constitute a water-filled transmembrane channel allowing passage of ions and other small, relatively non-specific molecules. Porins are also found in mitochondria and plants. (12 Dec 1998) |
| poriomania | <psychiatry> A morbid impulse to wander or journey away from home. Origin: G. Poreia, a journey, + mania, frenzy (05 Mar 2000) |
| porion | The central point on the upper margin of the external auditory meatus; as a cephalometric landmark, it is located in the middle of the metal rods of the cephalometer. Origin: G. Poros, a passage (05 Mar 2000) |
| porism | 1. <geometry> A proposition affirming the possibility of finding such conditions as will render a certain determinate problem indeterminate or capable of innumerable solutions. 2. <geometry> A corollary. Three books of porisms of Euclid have been lost, but several attempts to determine the nature of these propositions and to restore them have been made by modern geometers. Origin: Gr. A thing procured, a deduction from a demonstration, fr. To bring, provide: cf. F. Porisme. Source: Websters Dictionary (01 Mar 1998) |
| porite | <zoology> Any coral of the genus Porites, or family Poritidae. An important genus of reef-building corals having small twelve-rayed calicles, and a very porous coral. Some species are branched, others grow in large massive or globular forms. Origin: NL, fr. Gr. A pore. Source: Websters Dictionary (01 Mar 1998) |
| pork tapeworm | Known formally as Taenia solium, contracted from undercooked or measly pork (pork infected with the larval forms of the tapeworm). Can grow to be 3-6 feet (0.9-1.8 m) long in the human intestine. Also known as the armed tapeworm and the measly tapeworm. (12 Dec 1998) |
| porkwood | <botany> The coarse-grained brownish yellow wood of a small tree (Pisonia obtusata) of Florida and the West Indies. Also called pigeon wood, beefwood, and corkwood. Source: Websters Dictionary (01 Mar 1998) |
| pornographic | Of or pertaining to pornography; lascivious; licentious; as, pornographic writing. Source: Websters Dictionary (01 Mar 1998) |
| pornography | 1. Licentious painting or literature; especially, the painting anciently employed to decorate the walls of rooms devoted to bacchanalian orgies. 2. <medicine> A treatise on prostitutes, or prostitution. Origin: Gr. A harlot. Source: Websters Dictionary (01 Mar 1998) |
| pornolagnia | Sexual attraction toward prostitutes. Origin: G. Porne, prostitute, + lagneia, lust (05 Mar 2000) |
| poro- | 1. A pore, a duct, an opening. Origin: G. Poros (L. Porus), passageway 2. A doing through, a passing through. Origin: G. Poreia, a journey, passage 3. A callus; an induration. Origin: G. Poros, a kind of marble, a stone (05 Mar 2000) |
| porocele | An obsolete term for a hernia with indurated coverings. Origin: G. Poros, callus, + kele, hernia (05 Mar 2000) |
| porocephaliasis | Infection with a species of the tongue worms Porocephalus. Synonym: porocephalosis. (05 Mar 2000) |
| Porocephalidae | A family of parasitic tongue worms (order Porocephalida, phylum Pentastomida) characterised by four hooks arranged in a curved line on either side of the mouth. Adults are found in the lungs of reptiles, and larvae or nymphs are found in the tissues of a great variety of vertebrates, including humans. See: Linguatulidae, Armillifer, Linguatula. Origin: G. Poros, pore, + kephale, head (05 Mar 2000) |