| ras | retrovirus-associated DNA sequence |
|---|---|
| recon | the smallest unit of DNA capable of recombination [recombination + Gr. on quantum] |
| ss(c)DNA | single-stranded circular deoxyribonucleic acid |
| ssDNA | single-stranded DNA |
| Z-DNA | zig-zag (left-handed helical) deoxyribonucleic acid |
| indirect assay | For antibody; an application of the ELISA method in which serum being tested for antibody is added to wells coated with known antigen; presence of antibody bound to the antigen coat can be determined by addition of immunoglobulin-specific antibody to which is linked the enzyme of the indicator system, followed by addition of substrate to the washed aggregate. (05 Mar 2000) |
|---|---|
| Ouchterlony assay | <investigation> Immunological test for antigen antibody reactions in which diffusion of soluble antigen and antibody in a gel leads to precipitation of an antigen-antibody complex, visible usually as a whitish band. The system has the advantage that, because of radial diffusion of the reagents, a very wide range of ratios of antigen to antibody concentration develop, thus it is likely that precipitation will occur somewhere in the gel even when no care is taken with quantitation of the system. (18 Nov 1997) |
| EAC rosette assay | <haematology> Rosettes formed from erythrocytes (E) coated with antibody (A) and complement (C). A test for C3b or C3bi receptors (CR1 or CR3). The rosettes form more easily then E or EA rosettes. See: E rosettes. (16 Mar 2000) |
| enzyme-linked immunoabsorbent assay | <investigation> The enzyme-linked immunoabsorbent assay is serologic test used as a general screening tool for the detection of antibodies to the HIV virus. Reported as positive or negative. Since false positive tests due occur (for example recent flu shot), positives will require further evaluation using the western blot. ELISA technology links an a measurable enzyme to either an antigen or antibody. In this way, it can then measure the presence of an antibody or an antigen in the bloodstream. Acronym: ELISA (27 Sep 1997) |
| enzyme-linked immunosorbent assay | An immunoassay utilizing an antibody labelled with an enzyme marker such as horseradish peroxidase. While either the enzyme or the antibody is bound to an immunosorbent substrate, they both retain their biologic activity; the change in enzyme activity as a result of the enzyme-antibody-antigen reaction is proportional to the concentration of the antigen and can be measured spectrophotometrically or with the naked eye. Many variations of the method have been developed. (12 Dec 1998) |
| tumour stem cell assay | <investigation> A cytologic technique for measuring the functional capacity of tumour stem cells by assaying their activity. It is used primarily for the in vitro testing of antineoplastic agent. (12 Dec 1998) |
| factor II assay | A test used to measure the activity of a blood clotting factor (thrombin). This test may be used to evaluate excessive bleeding. Abnormally low factor II assays may be seen in the following conditions: congenital deficiency of factor II, fat malabsorption, heparin administration, cirrhosis, vitamin K deficiency and warfarin administration. (27 Sep 1997) |
| factor ix assay | A test used to measure the activity of a blood clotting factor IX (Christmas factor). This test may be used to evaluate excessive bleeding. Abnormally low factor IX assays may be seen in the following conditions: congenital deficiency of factor IX, fat malabsorption, heparin administration, cirrhosis, vitamin K deficiency and warfarin administration. (27 Sep 1997) |
| factor v assay | A test used to measure the activity of a blood clotting factor V. This test may be used to evaluate excessive bleeding. Abnormally low factor V assays may be seen in the following conditions: congenital deficiency of factor V, DIC, heparin administration, cirrhosis and primary fibrinolysis. (27 Sep 1997) |
| factor vii assay | A test used to measure the activity of a blood clotting factor VII. This test may be used to evaluate excessive bleeding. Abnormally low factor VII assays may be seen in the following conditions: congenital deficiency of factor VII, fat malabsorption, heparin administration, cirrhosis, vitamin K deficiency and warfarin administration. (27 Sep 1997) |
| factor viii assay | A test used to measure the activity of a blood clotting factor VIII (Von Willebrand factor). This test is usually used to monitor treatment of haemophilia. Abnormally low factor VIII assays may be seen in the following conditions: congenital deficiency of factor VIII (haemophilia), DIC and secondary fibrinolysis. This test may also be performed in the evaluation of Von Willebrand's disease. (27 Sep 1997) |
| factor x assay | A test used to measure the activity of a blood clotting factor X. This test may be used to evaluate excessive bleeding. Abnormally low factor X assays may be seen in the following conditions: congenital deficiency of factor X, fat malabsorption, heparin administration, cirrhosis, vitamin K deficiency and warfarin administration. (27 Sep 1997) |
| 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) |
| Farr type assay | <investigation> Method of radioimmunoassay in which free antigen remains soluble and antibody antigen complexes are precipitated. (18 Nov 1997) |
| 17-ketogenic steroid assay test | A colourimetric test, based on the Zimmermann reaction, which indicates metabolites or adrenal and testicular steroids excreted as 17-ketones in the urine; increased values are most striking in adrenocortical tumours, decreased values in Addison's disease or in panhypopituitarism. Synonym: ketogenic corticoids test. (05 Mar 2000) |