| radionuclide scan | An exam that produces pictures (scans) of internal parts of the body. The patient is given an injection or swallows a small amount of radioactive material. A machine called a scanner then measures the radioactivity in certain organs. (12 Dec 1998) |
|---|---|
| radionuclide ventriculography | Imaging of a ventricle of the heart after the injection of a radioactive contrast medium. The technique is less invasive than cardiac catheterization and is used to assess ventricular function. (12 Dec 1998) |
| gated radionuclide angiocardiography | Radionuclide angiocardiography using cardiac gating to combine images from several cardiac cycles to improve the quality of the images of separate phases (e.g., systole and diastole). (05 Mar 2000) |
| exercise radionuclide angiocardiography | Radionuclide angiocardiography while performing exercise, such as on a treadmill or bicycle. (05 Mar 2000) |
| aetiological fraction | <epidemiology> The reduction in disease when a risk factor is removed. If I* is the number of people that a risk factor is responsible for and I is the total number of cases over the same period, then the aetiological fraction is I*/I. Equivalently, the aetiological fraction is (I-Io)/I. Where Io is the number of cases in the absence of the risk factor. Also known as the attributable fraction. (05 Dec 1998) |
| amorphous fraction of adrenal cortex | Noncrystalline residue of an acetone extract of the adrenal cortex after crystalline steroids, e.g., corticosterone, deoxycorticosterone, etc., have been isolated. (05 Mar 2000) |
| attributable fraction | <epidemiology> The same as aetiological fraction. (05 Dec 1998) |
| recombination fraction | The proportion of progeny of a mating pair of specific genotype and coupling phase that are recombinant; there must be no differential selection among the possible types of progeny, and the recombination fraction should be the same regardless of the alleles involved or their coupling phase. (05 Mar 2000) |
| regurgitant fraction | The amount of blood regurgitated into a cardiac chamber divided by the stroke output; normally, no blood regurgitates; in patients with severe valvular lesions such as mitral or aortic insufficiency, regurgitation can approach 80%; this fraction affords a quantitative measure of the severity of the valvular lesion. (05 Mar 2000) |
| microsomal fraction | Artifactual vesicles formed from the endoplasmic reticulum when cells are disrupted. They are isolated by differential centrifugation and are composed of three structural features: rough vesicles, smooth vesicles, and ribosomes. Numerous enzyme activities are associated with the microsomal fraction. (glick, glossary of biochemistry and molecular biology, 1990; from rieger et al., glossary of genetics: classical and molecular, 5th ed) (12 Dec 1998) |
| mole fraction | The ratio of the moles of one component of a system to the total moles of all the components present. (05 Mar 2000) |
| human antihemophilic fraction | A lyophilised concentrate of factor VIII, obtained from fresh normal human plasma; used as a haemostatic agent in haemophilia. Synonym: antihemophilic globulin, human antihemophilic fraction. (05 Mar 2000) |
| human plasma protein fraction | A sterile solution of selected proteins derived from the blood plasma of adult human donors, containing 4.5 to 5.5 g of protein per 100 ml, of which 83 to 90% is albumin and the remainder is alpha-and beta-globulins; used as a blood volume supporter. (05 Mar 2000) |
| dried human plasma protein fraction | Freeze-dried human plasma protein fraction. (05 Mar 2000) |
| filtration fraction | The fraction of the plasma entering the kidney that filters into the lumen of the renal tubules, determined by dividing the glomerular filtration rate by the renal plasma flow; normally, it is around 0.17. (05 Mar 2000) |