| factor xii | <chemical> Stable blood coagulation factor activated by contact with the subendothelial surface of an injured vessel. Along with prekallikrein, it serves as the contact factor that initiates the intrinsic pathway of blood coagulation. Kallikrein activates factor xii to xiia. Deficiency of factor xii, also called the hageman trait, leads to increased incidence of thromboembolic disease. Chemical name: Blood-coagulation factor XII (12 Dec 1998) |
|---|---|
| factor xii assay | A test used to measure the activity of a blood clotting factor XII. This test may be used to evaluate excessive bleeding. Low factor XII may be seen in cases of congenital deficiency of factor XII, heparin administration and liver disease. (27 Sep 1997) |
| factor xii deficiency | A deficiency of a specific blood clotting factor (XII) that may be genetic or acquired. Administration of heparin or severe liver disease may result in factor XII (Hageman factor) deficiency. There are usually no symptoms associated with this deficiency, but there may be symptoms of mild blood loss in some cases. Treatment is generally unnecessary. Individuals should be cautioned against the use of medications (for example aspirin, warfarin, heparin) with anticoagulant activity, due to risk of exaggerated effects. (27 Sep 1997) |
| factor xiia | <enzyme> Activated form of factor xii. In the initial event in the intrinsic pathway of blood coagulation, kallikrein (with cofactor high molecular weight kininogen) cleaves factor xii to xiia. Factor xiia is then further cleaved by kallikrein, plasmin, and trypsin to yield smaller factor xii fragments (hageman-factor fragments). These fragments increase the activity of prekallikrein to kallikrein but decrease the procoagulant activity of factor xii. Registry number: EC 3.4.21.38 (12 Dec 1998) |
| factor xiii | <chemical> Fibrin stabilizing factor. It is a glycoprotein activated by thrombin in the presence of calcium to form factor xiiia. Factor xiii is found evenly distributed between plasma and platelets. Its function is to stabilise the formation of the fibrin polymer (clot) which culminates the coagulation cascade. Chemical name: Blood-coagulation factor XIII (12 Dec 1998) |
| factor xiii deficiency | A deficiency of blood coagulation factor xiii or fibrin stabilizing factor (fsf) which enables fibrin to form a firm blood clot. Deficiency of this factor produces a clinical haemorrhagic diathesis. (12 Dec 1998) |
| cranial nerve XII | <anatomy, nerve> The hypoglossal nerve enervates the muscles of the tongue. Lesions of the twelfth cranial nerve result in deviation of the tongue toward the paralysed side and thick speech. Synonym: cranial nerve XII. (27 Sep 1997) |
|---|---|
| Factors I XII | <haematology> Blood clotting factors, especially from humans. These factors form a cascade in which the activation of the first factor leads to enzymic attack on the next factor and so on, finally resulting in blood clotting. (18 Nov 1997) |
| accelerator factor | <chemical> Heat- and storage-labile plasma glycoprotein which accelerates the conversion of prothrombin to thrombin in blood coagulation. Factor v accomplishes this by forming a complex with factor xa, phospholipid, and calcium (prothrombinase complex). Deficiency of factor v leads to owren's disease. Chemical name: Blood-coagulation factor V (12 Dec 1998) |
| acetate replacement factor | <biochemistry> 1,2 dithiolane 3 valeric acid. Regarded as a coenzyme in the oxoglutarate dehydrogenase complex of the citric acid cycle. Involved generally in oxidative decarboxylations of _ keto acids. A growth factor for some organisms. (18 Nov 1997) |
| adrenal weight factor | A postulated substance of adenohypophysial origin responsible for maintenance of the weight of the adrenal cortex. (05 Mar 2000) |
| adrenocorticotropic releasing factor | Hormone produced by hypothalamus that causes pituitary to secrete adrenocorticotropic hormone. (05 Mar 2000) |
| a-factor | <molecular biology> A protein which is found in the bacterial genus Streptomyces that helps start the production of streptomycin and the process of morphological differentiation. It is used in biotechnology to induce these functions in mutant strains of Streptomyces that cannot produce it themselves. (09 Feb 1998) |
| angiogenesis factor | Substance causing proliferation of new blood vessels. It is found in tissues with high metabolic requirements, such as the retina, and in certain cancers. The factor is also released by hypoxic macrophages at the edges or outer surfaces of wounds and initiates revascularization in wound healing. (12 Dec 1998) |
| animal protein factor | <biochemistry> Member of the water soluble B vitamin group, important in the proper function of the nervous system and important in proper carbohydrate, protein and fat metabolism. (27 Sep 1997) |
| antialopecia factor | A member of the vitamin B complex necessary for growth of yeast and of mice, absence from the diet causes hair loss and dermatitis in mice. (27 Sep 1997) |
| antianaemic factor | <biochemistry> Member of the water soluble B vitamin group, important in the proper function of the nervous system and important in proper carbohydrate, protein and fat metabolism. (27 Sep 1997) |
| antiberiberi factor | Synonym: thiamin. (05 Mar 2000) |
| anti-black-tongue factor | A precursor of NAD, that is a product of the oxidation of nicotine. (18 Nov 1997) |
| anticomplementary factor | A factor that interferes with the action or function of complement. (05 Mar 2000) |
| antidermatitis factor | <chemical> Chemical name: beta-Alanine, N-(2,4-dihydroxy-3,3-dimethyl-1-oxobutyl)-, (R)- (12 Dec 1998) |