| VL | variable domain of the light chain; variable light chain |
|---|---|
| VNTR | variable number of tandem repeats; variable copy number tandem repeats |
| MC | mass casualties; mast cell; Master of Surgery [Lat. Magister Chirurgiae]; maximum concentration; Med... |
| MLTC | mixed leukocyte-trophoblast culture; mixed lymphocyte tumor cell |
| DRAM | dynamic random access memory |
| random mating equilibrium | <genetics> In a population containing the genotypes of AA, aa, and Aa, the frequency of AA will be p2, the frequency of aa will be q2, and the frequency of Aa will be 2 pq at equilibrium, where p is the frequency of A and q is the frequency of a. By the Hardy-Weinberg law, a ramdonly-mating population will eventually reach these frequencies and be at this equilibrium as long as there are no selection pressures on the population. (09 Oct 1997) |
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| random mechanism | A scheme for substrate binding and product release for a multisubstrate enzyme; for a two-substrate two-product enzyme with this mechanism, either substrate can bind first and, after the reaction has taken place, either product can be the first to dissociate from the enzyme. Brain hexokinase has a random mechanism. More complex random mechanisms exist for enzymes having more than two substrates. (05 Mar 2000) |
| random pattern flap | A flap in which the pedicle blood supply is derived randomly from the network of vessels in the area, rather than from a single longitudinal artery as in an axial pattern flap. (05 Mar 2000) |
| random sample | A group selected randomly, solely by chance. (12 Dec 1998) |
| random sampling | A selection of elements by a formal randomizing device for purposes of inference about a population of inference from that population in such a way that the probability of each possible outcome may be precisely specified in advance; the inferences are necessarily stochastic. (05 Mar 2000) |
| random walk | <cell biology> A description of the path followed by a cell or particle when there is no bias in movement. The direction of movement at any instant is not influenced by the direction of travel in the preceding period. If changes of direction are very frequent, then the displacement will be small, unless the speed is very great and the object will appear to vibrate on the spot. Although the behaviour of moving cells in a uniform environment can be described as a random walk in the long term, this is not true in the short term because of persistence. (18 Nov 1997) |
| random waves | Wave's in the electroencephalogram which occur paroxysmally and asynchronously. (05 Mar 2000) |
| moderator variable | A variable that interacts by virtue of being antecedent or intermediate in the causal pathway. (05 Mar 2000) |
| common variable immunodeficiency | Heterogeneous group of immunodeficiency syndromes characterised by hypogammaglobulinaemia of most isotypes, variable B-cell defects, and the presence of recurrent bacterial infections. (12 Dec 1998) |
| condenser, variable-focus | <microscopy> Essentially an Abbe condenser in which the upper lens element is fixed and the lower movable. The lower lens may be used to focus the illumination between the elements so that it emerges from the stationary lens as a large diameter parallel bundle. The field of low-power objectives may thus be filled without removing the top element. at the opposite extreme it can be adjusted to have a numerical aperture as high as 1.3. See: illumination, critical. (05 Aug 1998) |
| continuous variable | A variable that may take on any value in an interval or intervals (its domain). (05 Mar 2000) |
| sample, random | A group selected randomly, solely by chance. (12 Dec 1998) |
| pure random drift | That which has random components only with an average value of zero and no systematic effects. Brownian movement in a still container shows pure random drift but in the Mississippi shows a steady downstream tendency. (05 Mar 2000) |
| dependent variable | In experiments, a variable that is influenced by or dependent upon changes in the independent variable; e.g., the amount of a written passage retained (dependent variable) as a function of the different numbers of minutes (independent variable) allowed to study the passage. (05 Mar 2000) |
| discrete variable | A variable that may assume only a countable (usually finite) number of values. (05 Mar 2000) |