| astrobiology | <study> The study of life that potentially exists on planets or celestial bodiesother thanEarth. (09 Oct 1997) |
|---|---|
| astroblast | An embryonic astrocyte. (18 Nov 1997) |
| astroblastoma | <oncology, tumour> A rare form of cancer characterised by tumours made up of large cells withtwo or three nuclei. (09 Oct 1997) |
| astrocele | Synonym: centrosphere. Origin: G. Astron, star, + koilia, hollow (05 Mar 2000) |
| astrocyte | <pathology> A glial cell found in vertebrate brain, named for its characteristic star like shape. Astrocytes lend both mechanical and metabolic support for neurons, regulating the environment in which they function. See: oligodendrocytes. (18 Nov 1997) |
| astrocytes | The largest and most numerous neuroglial cells in the brain and spinal cord. Astrocytes (from "star" cells) are irregularly shaped with many long processes, including those with "end feet" which form the glial (limiting) membrane and directly and indirectly contribute to the blood-brain barrier. They regulate the extracellular ionic and chemical environment, and "reactive astrocytes" (along with microglia) respond to injury. Astrocytes have high- affinity transmitter uptake systems, voltage-dependent and transmitter-gated ion channels, and can release transmitter, but their role in signaling (as in many other functions) is not well understood. (12 Dec 1998) |
| astrocytoma | <oncology, tumour> A neuro ectodermal tumour (glioma) arising from astrocytes. Probably the commonest glioma, it has a tendency to become anaplastic. (18 Nov 1997) |
| astrocytosis | <pathology> An abnormal increase in the number of astrocytes due to the destruction of nearby neurons, typically because of hypoglycaemia or oxygen deprivation. (09 Oct 1997) |
| astrocytosis cerebri | A diffuse intracranial neoplasm of astrocytic origin. Synonym: astrocytosis cerebri, glioblastosis cerebri. (05 Mar 2000) |
| astroependymoma | <tumour> A glial neoplasm composed of a mixed population of astrocytic and ependymal cells. (05 Mar 2000) |
| astroglia | The largest and most numerous neuroglial cells in the brain and spinal cord. Astrocytes (from "star" cells) are irregularly shaped with many long processes, including those with "end feet" which form the glial (limiting) membrane and directly and indirectly contribute to the blood-brain barrier. They regulate the extracellular ionic and chemical environment, and "reactive astrocytes" (along with microglia) respond to injury. Astrocytes have high- affinity transmitter uptake systems, voltage-dependent and transmitter-gated ion channels, and can release transmitter, but their role in signaling (as in many other functions) is not well understood. (12 Dec 1998) |
| astroglia cell | <pathology> A glial cell found in vertebrate brain, named for its characteristic star like shape. Astrocytes lend both mechanical and metabolic support for neurons, regulating the environment in which they function. See: oligodendrocytes. (18 Nov 1997) |
| astrogliosis | <pathology> Hypertrophy of the astroglia, usually in response to injury. (18 Nov 1997) |
| astrography | The art of describing or delineating the stars; a description or mapping of the heavens. Origin: Astro'cf. Source: Websters Dictionary (01 Mar 1998) |
| astroid | Star-shaped. Origin: G. Astroeides, fr. Astron, star, + eidos, resemblance (05 Mar 2000) |