| FHC | familial hypercholesterolemia; family health center; Ficoll-Hypaque centrifugation; Fuchs heterochro... |
|---|---|
| IFC | intermittent flow centrifugation; intrinsic factor concentrate |
| TCBS | Thiosulfate Citrate Bile salt Sucrose agar |
| SM | Master of Science; sadomasochism; self-monitoring; silicon microphysiometer; simple mastectomy; skim... |
| SPE | septic pulmonary edema; serum protein electrolytes; serum protein electrophoresis; streptococcal pyr... |
| differential centrifugation | A technique for separating organellesor other differently-sized cellcomponents in a centrifuge, particles of the same size and weight willsettle out into common layers. (09 Oct 1997) |
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| equilibrium centrifugation | A type of density gradient centrifugation used to separate proteins or nucleic acids from a mixture. (09 Oct 1997) |
| zinc sulfate flotation centrifugation method | A flotation method in which the faecal specimen is suspended in tap water, strained through wet gauze, centrifuged, resuspended in tap water, washed and recentrifuged several times, and then suspended in 33% solution of zinc sulfate and centrifuged at top speed for 45 to 60 sec; a bacteriologic loop may be used to pick up the surface layer, which contains protozoan cysts and helminth eggs. (05 Mar 2000) |
| zone 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) |
| atrioventricular gradient | The diastolic pressure difference between the atrium and ventricle. (05 Mar 2000) |
| magnetic field gradient | In magnetic resonance imaging, a magnetic field that varies with location, superimposed on the uniform field of the magnet, to alter the resonant frequency of nuclei and allow recovery of their spatial position. Synonym: field gradient. (05 Mar 2000) |
| ventricular gradient | The algebraic sum of (i.e., the net electrical difference between) the area enclosed within the QRS complex and that within the T wave in the electrocardiogram. (05 Mar 2000) |
| voltage gradient | <physiology> Literally, the electric field in a region, defined as the potential difference between two points divided by the distance between them. Used more loosely, the potential difference across a plasma membrane. (18 Nov 1997) |
| gradient | <physics> Mathematical term for the operator which determines the magnitude and direction of the greatest rate-of-change of a given function with position. Similarly used to describe such a rate-of-change. For instance, at a given point on a hill, the slope of the hill in the steepest uphill direction is the gradient of the altitude function for the hill. (09 Oct 1997) |
| gradient elution | Elution in column chromatography in which a changing pH or ionic strength is used to separate substances. (05 Mar 2000) |
| gradient encoding | In magnetic resonance imaging, the technique of inducing a gradient in the magnetic field in the Y-axis to induce phase differences with location. Synonym: gradient encoding. (05 Mar 2000) |
| gradient perception | <cell biology> Problem faced by a cell that is to respond directionally to a gradient of, for example: a diffusible attractant chemical. In a spatial mechanism the cell would compare receptor occupancy at different sites on the cell surface, a temporal mechanism would involve comparison of concentrations at different times, the cell moving randomly between readings. In pseudospatial sensing, the cell would detect the gradient as a consequence of positive feedback to protrusive activity if receptor occupancy increased with time as the protrusion moved up gradient. Few cell types have been unambiguously shown to detect gradients. (18 Nov 1997) |
| mitral gradient | The diastolic pressure difference between the left atrium and left ventricle. (05 Mar 2000) |
| concentration 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) |
| 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) |