| TMU | tetramethyl urea |
|---|---|
| TSU | triple sugar urea [agar] |
| UC | ulcerative colitis; ultracentrifugal; umbilical cord; unchanged; unclassifiable; unconscious; undiff... |
| UCL | ulnar collateral ligament; upper collateral ligament; upper confidence limit; upper control limit; u... |
| UFFI | urea formaldehyde foam insulation |
| dicarboxylic acid cycle | That portion of the tricarboxylic acid cycle involving the dicarboxylic acids (succinic, fumaric, malic, and oxaloacetic acids), a cyclic scheme in which certain steps of the tricarboxylic acid cycle are used with the glyoxylate cycle; important in the utilization of glyoxylic acid in microorganisms. (05 Mar 2000) |
|---|---|
| direct life cycle | <epidemiology> A life cycle in which a parasite is transmitted directly from one host to the next without an intermediate host or vector of another species. (05 Dec 1998) |
| indirect life cycle | <epidemiology> A life cycle which requires one or more intermediate hosts before the definitive host species is reinfected. Compare direct, nondirect. (05 Dec 1998) |
| isometric period of cardiac cycle | That period in which the muscle fibres do not shorten although the cardiac muscle is excited and the pressure in the ventricles rises, extending from the closure of the atrioventricular valves to the opening of the semilunar valves (isovolumic constriction) or the reverse (isovolumic relaxation). (05 Mar 2000) |
| ornithine cycle | The metabolic pathway isfound in vertebrates and takes place in theliver, in it, urea is synthesised from amino acids and carbon dioxide. (09 Oct 1997) |
| ovarian cycle | The normal sex cycle which includes development of an ovarian (graafian) follicle, rupture of the follicle with discharge of the ovum, and formation and regression of a corpus luteum. (05 Mar 2000) |
| TCA cycle | <biochemistry> The central feaure of oxidative metabolism. Cyclic reactions whereby acetyl CoA is oxidized to carbon dioxide providing reducing equivalents (NADH or FADH2) to power the electron transport chain. Also provides intermediates for biosynthetic processes. (16 Dec 1997) |
| thermal conversion cycle | <radiobiology> Process of generating electrical power with a fusion reactor by means of a steam / other gas turbine. This is distinct from direct conversion cycles. (09 Oct 1997) |
| topping cycle | A cogeneration system in which electric power is produced first. The reject heat from power production is then used to produce useful process heat. (05 Dec 1998) |
| endogenous cycle | The portion of a parasitic life cycle occurring within the host. (05 Mar 2000) |
| tricarboxylic acid cycle | <biochemistry> The central feaure of oxidative metabolism. Cyclic reactions whereby acetyl CoA is oxidized to carbon dioxide providing reducing equivalents (NADH or FADH2) to power the electron transport chain. Also provides intermediates for biosynthetic processes. (16 Dec 1997) |
| estrous cycle | The series of physiologic uterine, ovarian, and other changes that occur in higher animals, consisting of proestrus, estrus, postestrus, and anestrus or diestrus. (05 Mar 2000) |
| estrus cycle | A reproductive cycle in some female mammals (but not female humans, who instead have menstrual cycles). The cycle is characterised by a short period of intense sexual desire (called estrus or heat) when the animal is fertile, which often occurs only once or twice a year, and involves correlating physical changes of the reproductive tract. (09 Oct 1997) |
| exoerythrocytic cycle | That nonpathogenic portion of the vertebrate phase of the life cycle of malarial organisms that takes place in liver cells, outside of the blood cells. (05 Mar 2000) |
| exogenous cycle | The portion of a parasitic life cycle occurring outside the host. (05 Mar 2000) |