| calorimetry | <chemistry> The science of measuring heat flow. (09 Jan 1998) |
|---|---|
| calorimetry, differential scanning | Differential thermal analysis in which the sample compartment of the apparatus is a differential calorimeter, allowing an exact measure of the heat of transition independent of the specific heat, thermal conductivity, and other variables of the sample. (12 Dec 1998) |
| calorimetry, indirect | Calculation of the energy expenditure in the form of heat production of the whole body or individual organs based on respiratory gas exchange. (12 Dec 1998) |
| non-direct transmission | <epidemiology> A mode of transmission that differs in some mysterious way from indirect transmission. (05 Dec 1998) |
| direct | 1. Straight, in a straight line. 2. Performed immediately and without the intervention of subsidiary means. Origin: L. Directus (18 Nov 1997) |
| direct acrylic restoration | A direct resin restoration of autopolymerizing acrylic. (05 Mar 2000) |
| direct agglutination | A general term for techniques which use the agglutination (macroscopic clumping) of particulate reagents as an indicator of the presence of an antigen-antibody reaction. Examples (haemagglutination, latex agglutination and coagglutination) follow. (05 Mar 2000) |
| direct B-cell | Lymphocytes responding to a small range of antigens by antibody production without any requirement for T-cells. The antigens include flagellin and pokeweed mitogen. (18 Nov 1997) |
| direct bilirubin | Conjugated bilirubin = Direct bilirubin. Bilirubin that has been chemically attached to a glucuronide in the liver. The bilirubin that is excreted into the bile by the liver and stored in the gallbladder or transferred to the duodenum. Normal direct bilirubin is 0 to 0.3 mg/dl. Greater than normal values can be seen in bile duct obstruction, cirrhosis, Crigler-Najjar syndrome, Dubin-Johnson syndrome and hepatitis. (27 Sep 1997) |
| direct bone impression | An impression of denuded bone, used in the construction of subperiosteal denture implants. (05 Mar 2000) |
| direct composite resin restoration | A direct restoration made by inserting a plastic mix of auto or light-polymerised resins in a cavity prepared in a tooth. Synonym: direct composite resin restoration. (05 Mar 2000) |
| direct contamination | <dentistry> Direct contact with impurities or germs. (for example by a patient sneezing on the assistant.) (08 Jan 1998) |
| direct Coombs' test | A test for detecting sensitised erythrocytes in erythroblastosis foetalis and in cases of acquired immune haemolytic anaemia: the patient's erythrocytes are washed with saline to remove serum and unattached antibody protein, then incubated with Coombs' anti-human globulin (usually serum from a rabbit or goat previously immunised with human globulin); after incubation, the system is centrifuged and examined for agglutination, which indicates the presence of so-called incomplete or univalent antibodies on the surface of the erythrocytes. (05 Mar 2000) |
| direct current | (DC) Electric current which travels continuously in the same direction over a sustained period of time, contrast with AC (Alternating Current) which oscillates as a function of time. (09 Oct 1997) |
| direct diuretic | A diuretic whose primary effect is on renal tubular function. (05 Mar 2000) |