| spheroids | Spherical, heterogeneous aggregates of proliferating, quiescent, and necrotic cells in culture that retain three-dimensional architecture and tissue-specific functions. They represent an in-vitro model for studies of the biology of both normal and malignant cells. Generally the ability to form spheroids is a characteristic trait of malignant cells derived from solid tumours, though cells from normal tissues can also form spheroids. (12 Dec 1998) |
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| spheromak | <radiobiology> A compact torus with comparable toroidal and poloidal magnetic fields. The plasma is roughly spherical and is usually surrounded by a close-fitting conducting shell or cage. Both the poloidal and toroidal magnetic fields are generated by plasma currents. There are no toroidal field coils linking the plasma through the central plasma axis. External force is supplied by poloidal field coils outside the plasma separatrix. The resulting configuration is approximately a force-free magnetic field. The spheromak machine geometry can be simpler than a tokamak, but the close-fitting wall is a source of impurities and the current cannot be inductively driven. After early experiments failed to achieve a reasonable beta, interest has ebbed. The spheromak can also be considered as the low-aspect-ratio limit of the tokamak. See: compact torus. (09 Oct 1997) |
| spheromere | <zoology> Any one of the several symmetrical segments arranged around the central axis and composing the body of a radiate anmal. Origin: Sphere + -mere. Source: Websters Dictionary (01 Mar 1998) |
| spherometer | <physics> An instrument for measuring the curvature of spherical surface, as of lenses for telescope, etc. Origin: Sphere: cf. F. Spherometre. Source: Websters Dictionary (01 Mar 1998) |
| spherophakia | A congenital bilateral aberration in which the lenses are small, spherical, and subject to subluxation; may occur as an independent anomaly or may be associated with the Weill-Marchesani syndrome. Origin: sphero-+ G. Phakos, lens (05 Mar 2000) |
| spheroplast | Bacterium from which the cell wall has been removed but that has not lysed. (18 Nov 1997) |
| spheroplasts | Bacterial, yeast, or fungal cells that result after partial removal of the rigid cell wall, which forms a membrane-bound cell with a spherical shape that is dependent for its integrity on an isotonic or hypertonic medium. (12 Dec 1998) |
| spheroprism | A spherical lens decentered to produce a prismatic effect, or a combined spherical lens and prism. (05 Mar 2000) |
| spherosiderite | <chemical> Siderite occuring in spheroidal masses. Origin: Sphere + siderite. Source: Websters Dictionary (01 Mar 1998) |
| spherosome | <plant biology> Lysosome like compartment in plants that derives from the endoplasmic reticulum and is a site for lipid storage. Origin: Gr. Soma = body (18 Nov 1997) |
| spherospermia | Spheroid spermatozoa lacking an elongated tail, in contrast to the threadlike, tailed sperm of humans and other mammals (nematospermia). Origin: sphero-+ G. Sperma, seed (05 Mar 2000) |
| spherule | 1. A small spherical structure. 2. A sporangial-like structure filled with endospores at maturity, produced within tissue and in vitro by Coccidioides immitis. Origin: LL. Sphaerula, dim. Of L. Sphaera, sphere, ball (05 Mar 2000) |
| spherulite | <chemical> A minute spherical crystalline body having a radiated structure, observed in some vitreous volcanic rocks, as obsidian and pearlstone. Origin: Cf. F. Spherulite. Source: Websters Dictionary (01 Mar 1998) |
| spheroplast |
(formerly also sphaeroplast) A microbial or plant cell from which most of the cell wall has been removed, usually by enzymic treatment. Strictly, in a spheroplast, some of the wall remains, while in a protoplast the wall has been completely removed. In practice, the two words are often used interchangeably. See protoplast.
출처: www.fao.org/docrep/003/X3910E/X3910E22.htm
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| sphere |
a round body whose surface is at all points the same distance from the center.
출처: library.thinkquest.org/5579/glossary/glossary.html
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| spherical |
in the shape of a sphere or globe; ball-shaped; rounded
출처: gmbis.marinebiodiversity.ca/BayOfFundy/glossMA.htm...
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| spherical aberration |
A lens fault which results in degraded image quality at the film plane. It is caused by light rays passing through the lens from a single point on the optical axis focused at different points according to incident height. Spherical aberration can be reduced by stopping down the lens.
출처: www.startphoto.com/learn/glossary/glossary_so-sz.h...
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| spherical |
A contact lens design that is like a sphere and is fairly common; in contrast, toric lenses for astigmatism are football-shaped and are less common.
출처: www.allaboutvision.com/resources/glossary-3.htm
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| spher | a measuring instrument for measuring the curvature of a surface |
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| spher | a small sphere |