| beta-globulins | The serum globulins with an electrophoretic mobility in neutral or alkaline solutions intermediate between that of alpha-globulins and gamma-globulins. (12 Dec 1998) |
|---|---|
| beta-glucocerebrosidase | <enzyme> An enzyme that hydrolyzes beta-glucosides in cerebrosides; a deficiency of this enzyme results in Gaucher disease. (05 Mar 2000) |
| beta-glucosidase | <enzyme> An enzyme that catalyses the hydrolysis of terminal non-reducing residues in beta-d-glucosides with release of beta-glucose. Chemical name: beta-D-Glucoside glucohydrolase Registry number: EC 3.2.1.21 (12 Dec 1998) |
| beta-glucosyl-hydroxymethylcytosine-alpha-glucosyltransferase | <enzyme> Generates gentobiosyl groups on the hydroxymethylcytosine of phage t2 and t6 DNA Registry number: EC 2.4.1.- Synonym: b-glc-hmc-a-glucosyltransferase (26 Jun 1999) |
| beta granule | A granule of a beta cell. (05 Mar 2000) |
| beta-haemolytic streptococci | Those that produce active haemolysins (O and S) which cause a zone of clear haemolysis on the blood agar medium in the area of the colony; beta-haemolytic streptococci are divided into groups (A to O) on the basis of cell wall C carbohydrate (see Lancefield classification); Group A (in the strains pathogenic for man) comprises more than 50 types (designated by Arabic numerals) determined by cell wall M protein, which seems to be associated closely with virulence and is produced chiefly by strains with matt or mucoid colonies, in contrast to nonvirulent, glossy colony-producing strains; other surface protein antigens such as R and T (T substance), and the nucleoprotein fraction (P substance) seem to be of less importance. The more than 20 extracellular substances elaborated by strains of beta-haemolytic streptococci include erythrogenic toxin (elaborated only by lysogenic strains), deoxyribonuclease (streptodornase), haemolysins (streptolysins O and S), hyaluronidase, and streptokinase. Synonym: haemolytic streptococci. (05 Mar 2000) |
| beta hcg | <radiology> Human chorionic gonadotrophin, beta subunit, 1800 mIU / ml (2nd I.S.), gestational sac should be seen in IUP, doubles every 24-48 hrs in normal IUP, slower rise in ectopic pregnancy (12 Dec 1998) |
| beta-hydroxybutyric acid | CH3CH(OH)CH2COOH;the d-stereoisomer is one of the ketone bodies and is formed in ketogenesis; it is an important fuel for extrahepatic tissues; as an acyl derivative it is also an intermediate in fatty acid biosynthesis. The l-isomer is found as a coenzyme A derivative in b oxidation of fatty acids. Synonym: 3-hydroxybutanoic acid, beta-hydroxybutyric acid. D-3-hydroxybutyric acid dehydrogenase, an enzyme that reversibly catalyses the interconversion of the two main ketone bodies, catalyzing acetoacetate + NADH + H+ &dblarr; d-3-hydroxybutyrate + NAD+. (05 Mar 2000) |
| beta-hydroxyisobutyric acid | HOCH2CH(CH3)COOH;an intermediate in the degradation of l-valine. (05 Mar 2000) |
| beta-hydroxypropionic acid | A minor intermediate in propionate and methylmalonate metabolism. See: beta-hydroxypropionic aciduria. (05 Mar 2000) |
| beta-hydroxypropionic aciduria | Elevated levels of beta-hydroxypropionic acid in the urine; seen in defects in methylmalonic acid and propionate metabolism, as well as in ketotic hyperglycinaemia syndrome. (05 Mar 2000) |
| beta-hypophamine | <protein> A peptide hormone released from the posterior pituitary lobe but synthesised in the hypothalamus. There are 2 forms, differing only in the amino acid at position 8: arginine vasopressin is widespread, while lysine vasopressin is found in pigs. Has antidiuretic and vasopressor actions. Used in the treatment of diabetes insipidus. (18 Nov 1997) |
| beta interferon | A protein liberated by fibroblasts in response to a viral infection. (27 Sep 1997) |
| beta-ketoacyl-ACP reductase | A part of the fatty acid synthase complex; an enzyme reversibly reacting 3-oxoacyl-ACP with NADPH to form d-3-hydroxyacyl-ACP and NADP+. Synonym: beta-ketoacyl-ACP reductase. (05 Mar 2000) |
| beta-ketoacyl-ACP synthase | <enzyme> An enzyme condensing malonyl-ACP and acyl-cys-protein to 3-oxoacyl-ACP + cys-protein + CO2, and similar reactions, as steps in fatty acid synthesis; cys-protein is also a part of the fatty acid synthase complex. Synonym: acyl-malonyl-ACP synthase, beta-ketoacyl-ACP synthase. (05 Mar 2000) |