| EF | ectopic focus; edema factor; ejection fraction; elastic fibril; electric field; elongation factor; e... |
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| VFID | virtual focus-isocenter-distance |
| FF | degree of fineness of abrasive particles; fat-free; father factor; fecal frequency; fertility factor... |
| VCPI | Virtual Control Program Interface |
| VE | vaginal examination; Venezuelan encephalitis; venous emptying; venous extension; ventilation; ventil... |
| VE | Virtual Endoscopy |
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| VE | Virtual Environment |
| VR | Virtual Reality |
| VRML | Virtual Reality Modeling Language |
| FGD | Focus Group Discussions |
| virtual focus | The point from which divergent rays seem to proceed, or that at which they would meet if prolonged backward. (05 Mar 2000) |
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| virtual image | <microscopy> Such as seen in a mirror or through a magnifier. A virtual image has no real existence in space as does a real image from a lens. It does have a definite location, however, caused by the angles of divergence of the rays received by the eye. This can be shown by the common school experiment of placing a pin coincident with its mirror image behind a sheet of glass acting as a partial mirror. Its location can also be placed in design by extrapolating backwards to a focus. If a magnifier is used as it should be, with the object at its focus, the virtual image is at infinity. The same is true for a microscope focused for the relaxed eye. See: distance of virtual image. (05 Aug 1998) |
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| distance of virtual image | <physics> When a simple lens is used as a magnifier for visual observation the eye becomes part of the optical system. A virtual image can be formulated by construction and its apparent distance will vary with the focus of the eye. This will vary among individuals. In a rather arbitrary but standardised assumption, the normal distance for close observation, or reading has been set at 10 inches (250 mm). The optics for the compound microscope have been designed to furnish parallel light from the eyepiece so that the eyes are relaxed for distant viewing. This makes the virtual image lie at infinity. Tests showed that the average observer accommodates somewhat, placing the virtual image rather variably, often about 20 - 25 feet. (05 Aug 1998) |
| image virtual | <microscopy> A virtual image has no real existence. It is the image seen when looking into a mirror. The field of view of the microscope is a good example of a virtual image. When the eye operates in conjunction with a lens to form an image on the retina, the visual sensation is as if the image existed in space. That its apparent location is very definite is proved when a pin can be made to coincide with the mirror (virtual) image of another pin that is seen by looking at a sheet of glass acting as a mirror. With a lens system a virtual image can be definitely located as by graphically tracing rays back to a focus. In a microscope, if the eye is relaxed as it should be, the virtual image will be at infinity. Measurements show that most observers place the aerial image at 20-25 feet, some as close as seven, because of partial accommodation. (11 Mar 1998) |
| real focus | The point of meeting of convergent rays. (05 Mar 2000) |
| Ghon's focus | Calcification seen in pulmonary parenchyma (usually mid-lung area) and hilar nodes resulting from earlier, usually childhood, infection with tuberculosis. Synonym: Ghon's complex, Ghon's focus, Ghon's primary lesion. (05 Mar 2000) |
| mink cell focus-inducing viruses | Murine leukaemia viruses discovered in 1976 by hartley, wolford, old, and rowe and so named because the viruses originally isolated had the capacity to transform cell foci in mink cell cultures. Mcf viruses are generated in a multi-step process by recombination with other viral types including akr, friend, moloney, and rauscher. (12 Dec 1998) |
| plasma focus | <radiobiology> The Plasma Focus is another device which depends on the pinch effect. Possible applications include both fusion and plasma propulsion, as well as other plasma research. In essence the plasma focus is generated by discharge of a current across the ends of two coaxial insulated conducting pipes. The Plasma Focus caused a huge stir when they generated copious neutrons, until it was discovered that the source of the neutrons was knockoffs from deuterium due to pinch accelerated electrons or ions. Plasma focus is sort of a point version of the Zpinch. (09 Oct 1997) |
| condenser, variable-focus | <microscopy> Essentially an Abbe condenser in which the upper lens element is fixed and the lower movable. The lower lens may be used to focus the illumination between the elements so that it emerges from the stationary lens as a large diameter parallel bundle. The field of low-power objectives may thus be filled without removing the top element. at the opposite extreme it can be adjusted to have a numerical aperture as high as 1.3. See: illumination, critical. (05 Aug 1998) |
| principal focus | The real or virtual meeting point of rays passing into a lens parallel to its axis. (05 Mar 2000) |
| spleen focus-forming viruses | Murine leukaemia viruses that are replication-defective and rapidly transforming. The envelope gene plays an essential role in initiating erythroleukaemia, manifested by splenic foci, splenomegaly, and polycythemia. Spleen focus-forming viruses are generated by recombination with other viral types including friend p (polycythemia), friend a (anaemia), rauscher, and cas (from wild mice at lake casita, california). (12 Dec 1998) |
| natural focus of infection | An ecosystem in which an infectious agent normally persists in nature; e.g., yellow fever virus in a jungle monkey-Haemagogus mosquito ecosystem. (05 Mar 2000) |
| depth of focus | <microscopy> The depth or thickness of the image space that is simultaneously in acceptable focus. The range of distances between a lens and image plane (target in the video pickup device) for which the image formed by the lens at a given setting is clearly focused. With a high-numerical aperture microscope objective, the depth of field is very shallow, but the depth of focus can be quite deep and reach several millimetres. (05 Aug 1998) |
| focus | Group of (frequently neoplastic) cells, identifiable by distinctive morphology or histology. (18 Nov 1997) |
| focus-forming assay | <investigation> A lab technique used to find out if a particular piece of DNA contains oncogenes (genes which are associated with cancer). This is done by putting the DNA into animal cells which normally show contact inhibition, or which stop growing when they come into physical contact with other cells or reach a certain density in the culture. If the cells lose contact inhibition and form areas of densely-packed cells (called foci) after receiving the DNA, it means that the DNA did contain oncogenes. (05 Jan 1997) |
| focus-forming unit | A measurement of the concentration of live virus in a given amount of fluid. This is measured by spreading a known amount of the fluid over a layer of cultured cells which are infected by the virus, then counting the number of areas in the culture which look infected. (09 Oct 1997) |
제품명 |
판매사 |
보험코드 | 성분/함량 | 구분/보험급여 |
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제품명 |
판매사 |
보험코드 | 성분/함량 | 구분/보험급여 |
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