| NARAL | National Abortion Rights Action League |
|---|---|
| NAT | N-acetyltransferase; natal; neonatal alloimmune thrombocytopenia; no action taken; nonaccidental tra... |
| RA | radioactive; ragocyte; ragweed antigen; rapidly adapting [receptors]; reactive arthritis; reciprocal... |
| RAT | repeat action tablet; rheumatoid arthritis test |
| RBAP | repetitive bursts of action potential |
| tricuspid valve stenosis | The pathologic narrowing of the orifice of the tricuspid valve. (12 Dec 1998) |
|---|---|
| Tulpius' valve | The bilabial prominence of the terminal ileum into the large intestine at the caecocolic junction as seen in cadavers; in the living individual it appears as a truncated cone with a star-shaped orifice. Synonym: valva ileocaecalis, Bauhin's valve, ileocaecal eminence, ileocolic valve, Tulp's valve, Tulpius' valve, valve of Varolius. (05 Mar 2000) |
| eustachian valve | An endocardial fold extending from the anterior inferior margin of the inferior vena cava to the anterior part of the limbus fossa ovalis. Synonym: valvula venae cavae inferioris, caval valve, eustachian valve, sylvian valve. (05 Mar 2000) |
| Krause's valve | A small fold in the interior of the lacrimal sac at its junction with the lacrimal duct. Synonym: Krause's valve. (05 Mar 2000) |
| floppy valve syndrome | <syndrome> Retrograde slippage of degenerating mitral or tricuspid valve leaflets into the valve's orifice beyond the point of closure during systole of the left ventricle; a feature of Barlow's syndrome. (05 Mar 2000) |
| frenulum of ileocaecal valve | A fold, more evident in cadavers, running from the junction of the two commissures of the ileocaecal valve on either side along the inner wall of the caecocolic junction. Synonym: frenulum valvae ileocaecalis, frenulum of Morgagni, Morgagni's frenum, Morgagni's retinaculum. (05 Mar 2000) |
| left atrioventricular valve | <anatomy, cardiology> The heart valve that divides the left atrium and left ventricle. During left atrial contraction, the mitral valve opens to allow blood to flow into the left ventricle. Upon closure, the mitral valve prohibits the regurgitation of blood back into the left atrium. The mitral valve is the only heart valve that has only 2 valve cusps (all others have 3). (13 Nov 1997) |
| lunula of semilunar valve | The free border of a semilunar valve at each side of the nodulus valvulae semilunaris. Synonym: lunula valvulae semilunaris. (05 Mar 2000) |