| radioactive tracer | <physics, radiobiology> A radioisotope is an element which has the same atomic number as another but a different atomic weight, exhibiting the property of spontaneous decomposition. Decomposition gives off radiation (gamma rays) that can be detected with a counter. If a radioisotope is attached to a biological compound and injected into the body, its path may be traced through the body (resulting in an image). (27 Sep 1997) |
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| tracer | 1. An element or compound containing atoms that can be distinguished from their normal counterparts by physical means (e.g., radioactivity assay or mass spectrography) and can thus be used to follow (trace) the metabolism of the normal substances. 2. A coloured substance (e.g., a dye) used as a tracer to follow the flow of water. 3. An instrument used in dissecting out nerves and blood vessels. 4. A mechanical device with a marking point attached to one jaw and a graph plate or tracing plate attached to the other jaw; used to record the direction and extent of movements of the mandible. See: tracing. Origin: M.E. Track, fr. O. Fr. Tracier, to make one's way, fr. L. Traho, pp. Tractum, to draw, + -er, agent suffix (05 Mar 2000) |
| tracer/y | Ornamental work with rambled lines. Especially: The decorative head of a Gothic window. Window tracery is of two sorts, plate tracery and bar tracery. Plate tracery, common in Italy, consists of a series of ornamental patterns cut through a flat plate of stone. Bar tracery is a decorative pattern formed by the curves and intersections of the molded bars of the mullions. Window tracery is imitated in many decorative objects, as panels of wood or metal either pierced or in relief. See also Stump tracery under Stump, and Fan tracery under Fan. A similar decoration in some styles of vaulting, the ribs of the vault giving off the minor bars of which the tracery is composed. Source: Websters Dictionary (01 Mar 1998) |
| Abbott's method | A method of treatment of scoliosis by use of a series of plaster jackets applied after partial correction of the curvature by external force. (05 Mar 2000) |
| Abell-Kendall method | A standard method for estimation of total serum cholesterol involving saponification of cholesterol ester by hydroxide, extraction with petroleum ether, and colour development with acetic anhydride-sulfuric acid; the method avoids interference by bilirubin, protein, and haemoglobin. (05 Mar 2000) |
| activated sludge method | A method of sewage disposal in which the sewage is treated with 15% bacterially active, liquid sludge, which is produced by repeated vigorous aeration of fresh sewage to form floccules or sediment; when this flocculation process is complete, the resulting activated sludge contains large numbers of bacteria, together with yeasts, molds, and protozoa, which actively effect the oxidation of organic compounds; this mixture is piped to a sedimentation tank, the effluent from which is completely treated sewage. (05 Mar 2000) |
| Altmann-Gersh method | The method of rapidly freezing a tissue and dehydrating it in a vacuum. (05 Mar 2000) |
| Anel's method | Ligation of an artery immediately above (on the proximal side of) an aneurysm. (05 Mar 2000) |
| Antyllus' method | Ligation of the artery above and below an aneurysm, followed by incision into and emptying of the sac. (05 Mar 2000) |
| aristotelian method | A method of study that stresses the relation between a general category and a particular object. (05 Mar 2000) |
| Ashby method | A differential agglutination method for estimating erythrocyte life span; compatible blood possessing a group factor that the recipient lacks is transferred to the recipient; after the transfusion, sera with potent agglutinins for the recipient's red cells are added to samples of the recipient's blood, and the unagglutinated red cells are counted; using this technique the red cell life span in normal persons is found to be 110 to 120 days. (05 Mar 2000) |
| auxanographic method | A method for the study of bacterial enzymes in which agar is mixed with the material (e.g., starch or milk) which is to serve as an indicator of the enzyme action and is inoculated and plated; if the bacteria produce enzymes digesting the admixed material, there will be a zone of clearing in the medium about each colony. Synonym: diffusion method. (05 Mar 2000) |
| Barraquer's method | Zonulysis Dissolution of the zonula ciliaris by enzymes (alpha-chymotrypsin) to facilitate surgical removal of a cataract. Synonym: Barraquer's method. Origin: zonule + G. Lysis, dissolution (05 Mar 2000) |
| Beck's method | A permanent opening into the stomach made from its greater curvature. (05 Mar 2000) |
| Bier's method | Treatment of various surgical conditions by reactive hyperaemia. (05 Mar 2000) |