| WLM | white light microscopy; working level month [radon] |
|---|---|
| LR | labeled release; laboratory references; laboratory report; labor room; lactated Ringer [solution]; l... |
| NLP | no light perception; nodular liquefying panniculitis; normal light perception; normal luteal phase |
| VL | variable domain of the light chain; variable light chain |
| EM | 1) Erythro-Mycin 2) Electron Microscopy |
| microscopy, electron, scanning | Microscopy in which the object is examined directly by an electron beam scanning the specimen point-by-point, giving the surface image a three-dimensional quality. (12 Dec 1998) |
|---|---|
| microscopy, electron, scanning transmission | A type of electron microscopy which scans with an extremely narrow beam that is transmitted through the sample. The detection apparatus produces an image whose brightness depends on the atomic number of the sample. It should not be confused with microscopy, electron scanning nor with microscopy, electron, transmission (see microscopy, electron). (12 Dec 1998) |
| microscopy, fluorescence | Microscopy of specimens stained with fluorescent dye (usually fluorescein isothiocyanate) or of naturally fluorescent materials, which emit light when exposed to ultraviolet or blue light. Immunofluorescence microscopy utilises antibodies that are labelled with fluorescent dye. (12 Dec 1998) |
| microscopy, immunoelectron | Microscopy in which the samples are first stained immunocytochemically and then examined using an electron microscope. Immunoelectron microscopy is used extensively in diagnostic virology as part of very sensitive immunoassays. (12 Dec 1998) |
| microscopy, interference | Microscopy in which physiological and photometric contrast in the image is influenced or produced by the action of optical components which regulate interference. (12 Dec 1998) |
| microscopy, phase-contrast | A form of interference microscopy in which variations of the refracting index in the object are converted into variations of intensity in the image. This is achieved by the action of a phase plate. (12 Dec 1998) |
| microscopy, polarization | Microscopy using polarised light in which phenomena due to the preferential orientation of optical properties with respect to the vibration plane of the polarised light are made visible and correlated parameters are made measurable. (12 Dec 1998) |
| microscopy, scanning tunneling | Electron microscopy in which a very sharp conducting needle is swept just a few angstroms above the surface of a sample. The tiny tunneling current that flows between the sample and the needle tip is measured and from this are produced three-dimensional topographs, with a lateral resolution often as good as 1-2 angstroms and a vertical resolution of less than 1 angstrom. Due to their composition, biological samples are usually coated with a conductive layer, e.g., by depositing a thin metal or carbon film on top of the sample, to enhance their conductivity. (12 Dec 1998) |
| microscopy, ultraviolet | Microscopy in which the image is formed by ultraviolet radiation and is displayed and recorded by means of photographic film. (12 Dec 1998) |
| microscopy, video | Microscopy in which television cameras are used to brighten magnified images that are otherwise too dark to be seen with the naked eye. It is used frequently in telepathology. (12 Dec 1998) |
| confocal microscopy | <procedure> A system of (usually) epifluorescence light microscopy in which a fine laser beam of light is scanned over the object through the objective lens. The technique is particularly good at rejecting light from outside the plane of focus and so produces higher effective resolution than is normally achieved. (18 Nov 1997) |
| Conventional Transmission Electron Microscopy | <technique> A term applied to 'normal' transmission electron microscopy imaging. The electron beam is passed through a thin film sample (typically ~1-200 nm thick). Bright field diffraction contrast images are formed with the direct (undiffracted) beam. Dark field images are formed with a selected diffracted beam. CTEM imaging is used in the general observation of samples and careful selection of the diffracting conditions of the sample will allow the analysis of defect structures within the sample. (05 Aug 1998) |
| polarization microscopy | <procedure> Any form of microscopy capable of detecting birefringent objects. Usually performed with a polarizing element below the stage to produce plane polarized light and an analyser that is set to give total extinction of the background and thus to detect any birefringence. (18 Nov 1997) |
| scanning electron microscopy | <procedure> Technique of electron microscopy in which the specimen is coated with heavy metal and then scanned by an electron beam. The image is built up on a monitor screen (in the same way as the raster builds a conventional television image). The resolution is not so great as with transmission electron microscopy, but preparation is easier (often by fixation followed by critical point drying), the depth of focus is relatively enormous, the surface of a specimen can be seen (though not the interior unless the specimen is cracked open) and the image is aesthetically pleasing. (18 Nov 1997) |
| Scanning Probe Microscopy | <technique> Initially called Atomic Force Microscopy, this technique is now more typically termed Scanning Force Microscopy or Scanning Probe Microscopy. This instrument is essentially an extremely high resolution profilometre. A sharp tip, typically fabricated from silicon nitride, is scanned across the surface of a sample at a constant force by three piezoelectric ceramics. The piezoelectric ceramics are computer controlled via a feedback loop which monitors the position of the tip by means of an optical lever. (A laser is focused on the top of the tip support and the beam reflected into a position sensitive detector). The changes in height of the tip are used to form an image as the tip is scanned across the sample. Acronym: SPM (26 Mar 1998) |