| time-varied gain control | In ultrasonography, an increase in receiver gain with time to compensate for loss in echo amplitude with depth, usually due to attenuation. Synonym: attenuation compensation, depth compensation, time compensation gain, time-compensated gain, time-varied gain control, time-varied gain. (05 Mar 2000) |
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| tissue thromboplastin inhibition time | A test used to identify lupus anticoagulant; the thromboplastin source used in the prothrombin test is diluted to increase sensitivity to inhibitors. (05 Mar 2000) |
| energy confinement time | <radiobiology> Characteristic time in which 1/e (or sometimes 1/2) of a system's energy is lost to its surroundings. In a plasma device, the energy loss time (or the energy confinement time) is one of three critical parameters determining whether enough fusion will occur to sustain a reaction. See: Lawson criterion. (09 Oct 1997) |
| energy replacement time | <radiobiology> Time required for a plasma to lose (via radiation or other loss mechanisms) an amount of energy equal to its average kinetic energy. (09 Oct 1997) |
| euglobulin clot lysis time | A measure of the ability of plasminogen activators and plasmin to lyse a clot; normally, clot lysis is determined by the balance of factors which activate fibrinolysis (plasminogen activators and plasmin) and those which inhibit lysis; in certain conditions (e.g., carcinoma or hepatic insufficiency) activating factors predominate and can be measured by noting the time it takes the euglobulin fraction of plasma (excluding inhibitors of fibrinolysis) to clot. (05 Mar 2000) |
| fading time | The time required for a constant stimulus applied to a fixed area of the peripheral visual field to stop. (05 Mar 2000) |
| zero time-binding DNA | DNA that has become the duplex form at the start of a reassociation process. Acronym: DNA (05 Mar 2000) |
| utilization time | The minimum duration of a stimulus of rheobasic strength that is just sufficient to produce excitation. Synonym: temps utile. (05 Mar 2000) |
| forced expiratory time | The time taken to expire a given volume or a given fraction of vital capacity during measurement of forced vital capacity; subscripts specify the exact parameters measured. (05 Mar 2000) |
| left ventricular ejection time | The time measured clinically from onset to incisural notch of the carotid or other pulse; properly the time of ejection of blood from the left ventricle beginning with aortic valve opening and ending with aortic valve closure. (05 Mar 2000) |
| ABO blood group | <haematology> The major human blood type system which describes the oligosaccharide glycoprotein antigens found on the surface of human blood cells. According to the type of antigen present, a person may be assigned a blood type of A, B, AB or O. A second type of antigen, the Rh factor, renders a positive or negative blood type. The ABO blood group system is important because it determines who can donate blood to or accept blood from whom. Type A or AB blood will cause an immune reaction in people with type B blood and type B and AB blood will cause a reaction in people with type A blood. Conversely, type O blood has no A or B antigens, so people with type O blood are universal donors. And since AB blood already produces both antigens, people who are type AB can accept any of the other blood types without suffering an immune reaction. (04 Jul 1999) |
| Almen's test for blood | Glacial acetic acid, gum guaiac solution, and hydrogen peroxide are added to an aqueous suspension of the suspected stain; if occult blood or blood pigment is present, a blue colour develops. Synonym: guaiac test, Schonbein's test, van Deen's test. (05 Mar 2000) |
| arterial blood | Blood that is oxygenated in the lungs, found in the left chambers of the heart and in the arteries, and relatively bright red. (05 Mar 2000) |
| arterial blood gas | A test which analyses arterial blood for oxygen, carbon dioxide and bicarbonate content in addition to blood pH. Used to test the effectiveness of respiration. Acronym: ABG (17 Oct 1997) |
| blood | <haematology> Considered a circulating tissue composed of a fluid portion (plasma) with suspended formed elements (red blood cells, white blood cells, platelets). Arterial blood is the means by which oxygen and nutrients are transported to tissues, venous blood is the means by which carbon dioxide and metabolic by-products are transported for excretion. (05 Jan 1998) |