| backward curvature | Curvature in which a more distal or cephalad part is deviated posteriorly with respect to the coronal anatomic plane. (05 Mar 2000) |
|---|---|
| backward heart failure | A concept (formerly considered mutually exclusive of forward heart failure) that maintains that the phenomena of congestive heart failure result from passive engorgement of the veins caused by a "backward" rise in pressure proximal to the failing cardiac chambers. Compare: forward heart failure. (05 Mar 2000) |
| metal interface | In dentistry, a boundary between metal and nonsolvent solder, or between metal and surface oxide. (05 Mar 2000) |
| crystalline interface | In dentistry, a boundary between adjacent crystals. (05 Mar 2000) |
| structural interface | In dentistry, a boundary between tooth and restorative material. (05 Mar 2000) |
| dermoepidermal interface | The line of meeting of the dermis and epidermis. (05 Mar 2000) |
| interface | 1. A surface that forms a common boundary of two bodies. 2. The boundary between regions of different radiopacity, acoustic, or magnetic resonance properties; the projection of the interface between tissues of different such properties on an image. (05 Mar 2000) |
| user-computer interface | The portion of an interactive computer program that issues messages to and receives commands from a user. (12 Dec 1998) |
| band 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) |
| centrifugation | <procedure> The process of separating fractions of systems in a centrifuge. The most basic separation is to sediment a pellet at the bottom of the tube, leaving a supernatant at a given centrifugal force. In this case sedimentation is determined by size and density of the particles in the system amongst other factors. Density may be used as a basis for sedimentation in density gradient centrifugation. at very high g values molecules may be separated, i.e. Ultracentrifugation. In continuous centrifugation the supernatant is removed continuously as it is formed. (13 Nov 1997) |
| centrifugation, density gradient | Separation of particles according to density by employing a gradient of varying densities. at equilibrium each particle settles in the gradient at a point equal to its density. (12 Dec 1998) |
| centrifugation, isopycnic | Centrifugation in which the solvent is of the same density as the substance to be isolated. From the greek iso-, equal and pyknos, thick. (12 Dec 1998) |
| centrifugation, zonal | Centrifugation using a rotating chamber of large capacity in which to separate cell organelles by density-gradient centrifugation. (12 Dec 1998) |
| cesium chloride gradient centrifugation | A type of density gradient centrifugation, a lab technique used to separate or purify nucleic acids. It involves putting cesium chloride and the nucleic acids into a centrifuge to be spun for hours or days. The cesium chloride forms a density gradient (highly dense at the bottom, thinnest at the top), and the different nucleic acids separate along the gradient according to their buoyancies in different densities. (09 Oct 1997) |
| 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) |