| TPG | transmembrane potential gradient; transplacental gradient; tryptophan peptone glucose [broth] |
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| MR | Maddox rods; magnetic resistance; magnetic resonance; mandibular reflex; mannose-resistant; may repe... |
| MF | magnetic field; meat free; medium frequency; megafarad; membrane filler; merthiolate-formaldehyde [s... |
| TVMF | time varying magnetic field |
| EF | ectopic focus; edema factor; ejection fraction; elastic fibril; electric field; elongation factor; e... |
| critical gradient | <botany> The maximum stable inclination of an unsupported slope under the most adverse conditions that it will likely experience, as determined by current engineering technology. (09 Oct 1997) |
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| pseudospatial gradient sensing | <cell biology> Mechanism for sensing a gradient of a diffusible chemical in which the cell sends protrusions out at random, up gradient protrusions are stabilised by positive feedback (because receptor occupancy is rising with time) and others are transitory because of adaptation. Possibly the mechanism by which neutrophils sense chemotactic gradients. (18 Nov 1997) |
| density gradient | <chemistry> A column of liquid in which the density varies continually with position, usually as a consequence of variation of concentration of a solute. Such gradients may be established by progressive mixing of solutions of different density as for example: sucrose gradients) or by centrifuge induced redistribution of solute (as for caesium chloride gradients). Density gradients are widely used for centrifugal and gravity induced separations of cells, organelles and macromolecules. The separations may exploit density differences between particles or primarily differences in size, in which latter case the function of the gradient is chiefly to stabilise the liquid column against mixing. (12 Jan 1998) |
| density gradient centrifugation | <technique> High-speed centrifugation inwhich molecules float at a point wheretheir density equals that in a gradient of cesium chloride or sucrose. (12 Jan 1998) |
| systolic gradient | The difference in pressure during systole between two communicating cardiovascular chambers, e.g., between the left ventricle and aorta in aortic stenosis. (05 Mar 2000) |
| electrochemical gradient | A measure of the tendency of an ion to move passively from one point to another, taking into consideration the differences in its concentration and in the electrical potentials between the two points; commonly expressed as the additional voltage needed to achieve equilibrium. (05 Mar 2000) |
| ficoll gradient | A density gradient of ficoll (synthetic sucrose polymer) in solution, where concentration of the ficoll varies continuously through the solution. It is often used to separate different types of cells from each other during the process of sedimentation. (09 Oct 1997) |
| biological vector | A vector, such as the Anopheles mosquito for malarial agents or the tsetse fly for agents of African sleeping sickness, in which the agent multiplies prior to being transmitted to another host. (05 Mar 2000) |
| radius vector | 1. <mathematics> A straight line (or the length of such line) connecting any point, as of a curve, with a fixed point, or pole, round which the straight line turns, and to which it serves to refer the successive points of a curve, in a system of polar coordinates. See Coordinate. 2. <astronomy> An ideal straight line joining the center of an attracting body with that of a body describing an orbit around it, as a line joining the sun and a planet or comet, or a planet and its satellite. Source: Websters Dictionary (01 Mar 1998) |
| vector | 1. <mathematics> A term to describe something that has both direction and magnitude. 2. <molecular biology> Commonly term for a plasmid that can be used to transfer DNA sequences from one organism to another. Different vectors may have properties particularly appropriate to give protein expression in the recipient or for cloning or may have different selectable markers. Recombinant DNA systems especially suited for production of large quantities of specific proteins in bacterial, yeast, insect, or mammalian cell systems. See: transfection. (05 Mar 2000) |
| vector-borne | Denoting a disease or infection that is transmitted by an invertebrate vector. (05 Mar 2000) |
| vector loop | <physiology> An irregular, usually elliptical, curve representing the average direction and magnitude of the heart's action from moment to moment throughout the cardiac cycle. See: vector, vectorcardiogram. (06 Mar 2000) |
| mammalian expression vector | <molecular biology> A vector that will produce large amounts of eukaryotic protein taxonomy notwithstanding, and not necessarily a protein from a mammal. (20 Mar 1998) |
| manifest vector | Projection of a spatial cardiac vector on a single plane. (05 Mar 2000) |
| recombinant vector | A vector into which a foreign DNA has been inserted. Synonym: vector. (05 Mar 2000) |