| MD | Doctor of Medicine [Lat. Medicinae Doctor]; magnesium deficiency; main duct; maintenance dose; major... |
|---|---|
| MDD | major depressive disorder; mean daily dose |
| MPD | main pancreatic duct; maximum permissible dose; mean population doubling; membrane potential differe... |
| MTD | maximum tolerated dose; mean total dose; metastatic trophoblastic disease; Midwife Teacher's Diploma... |
| NCD | National Commission on Diabetes; National Council on Drugs; neurocirculatory dystonia; nitrogen clea... |
| eye lens | <physics> The lens nearest the eye in any ocular. (05 Aug 1998) |
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| fibres of lens | <biology, ophthalmology, physiology> The elongated cells of ectodermal origin forming the substance of the crystalline lens of the eye. Synonym: fibrae lentis. (05 Mar 2000) |
| field lens | <physics> The lower lens in an ocular, the lens nearest the object field. (05 Aug 1998) |
| lamina of lens | One of a series of concentric layers composed of the lens fibres that make up the substance of the lens. (05 Mar 2000) |
| Fresnel lens | <physics> A lens built up, progressively, in zones or steps, each zone with its own individual radius. Considerable spherical correction is attained, and the weight of the lens is greatly reduced. Fresnel lenses were originally designed for lighthouses but they are now attainable for small spotlights, automobile headlights, and similar uses. (05 Aug 1998) |
| front lens | <physics> The front element of a compound lens system, the first lens element which the entering light encounters. See: back lens. (05 Aug 1998) |
| lens | <physics> A transparent optical element, so constructed that it serves to change the degree of convergence or divergence of the transmitted rays. (05 Aug 1998) |
| lens, Bertrand | <microscopy> A small convergent lens placed between objectives and eyepiece. The lens focuses an image of the upper focal plane of the objective on the focal plane of the eyepiece. It is chiefly used with polarized light for inspecting the interference figure. It is also convenient for quickly verifying centreing, size, and uniform illumination of an aperture. (05 Aug 1998) |
| lens capsule | The capsule enclosing the lens of the eye. Synonym: capsula lentis, crystalline capsule, lenticular capsule, phacocyst. (05 Mar 2000) |
| lens capsule, crystalline | The noncellular outer covering of the crystalline lens, secreted by the embryonic anterior and posterior epithelium. The embryonic posterior epithelium later disappears. (12 Dec 1998) |
| lens clock | A device for measuring the radii of the curvature of a spectacle lens. Synonym: lens clock. Origin: Geneva, Switzerland (05 Mar 2000) |
| lens, compound | <microscopy> A lens composed of two or more separate pieces of glass or other optical maternal. These component pieces or elements may or may not be cemented together. A common form of compound lens is a two-element objective, one element being a converging lens of crown glass and the other a diverging lens of flint glass. The combination of suitable glasses or other optical materials (plastics, minerals) properly ground and polished reduces aberrations normally present in a single lens. (05 Aug 1998) |
| lens cortex, crystalline | The portion of the crystalline lens surrounding the nucleus and bound anteriorly by the epithelium and posteriorly by the capsule. It contains lens fibres and amorphous, intercellular substance. (12 Dec 1998) |
| lens, crystalline | The transparent biconvex body of the eye situated between the posterior chamber and the vitreous body, constituting part of the refracting mechanism of the eye. (12 Dec 1998) |
| lens, eye | <microscopy> The lens in an eyepiece nearest to the eye. (05 Aug 1998) |