| choroidal ring | A lightly pigmented crescent or ring adjacent to the optic disk. (05 Mar 2000) |
|---|---|
| ciliary ring | The darkly pigmented posterior zone of the ciliary body continuous with the retina at the ora serrata. Synonym: ciliary disk, ciliary ring, pars plana. Origin: Mod. L. (05 Mar 2000) |
| milk-ring test | A special form of agglutination test done on the pooled milk of many cows, usually entire herds, for the detection of herds containing individuals infected with bovine brucellosis. (05 Mar 2000) |
| mixed tumour of skin | <tumour> A benign tumour of sweat glands with a mucoid stroma showing cartilaginous metaplasia. Synonym: mixed tumour of skin. (05 Mar 2000) |
| physiologic retraction ring | A ridge on the inner uterine surface at the boundary line between the upper and lower uterine segment that occurs in the course of normal labour. (05 Mar 2000) |
| Waldeyer's throat ring | The broken ring of lymphoid tissue, formed of the lingual, faucial, and pharyngeal tonsils. Synonym: Bickel's ring, tonsillar ring, Waldeyer's throat ring. (05 Mar 2000) |
| piebald skin | Patchy absence of the pigment of scalp hair, giving a streaked appearance; patches of vitiligo may be present in other areas sue to absence of melanocytes; often transmitted as an autosomal dominant trait and may be associated with neurological defects or eye changes . Compare: Waardenburg syndrome. Synonym: piebald skin, piebaldism. (05 Mar 2000) |
| pigment cell of skin | Special cells in the skin and the eye that synthesise melanin pigments. Clusters of melanocytes often appear on the skin as moles. In fish and reptiles, the pigments are stored in melanosomes (chromatophores) that can be redistributed in the cytoplasm to change pigment patterns. Synonym: melanodendrocyte. Origin: melano-+ G. + kytos, a hollow (cell) (29 Sep 1997) |
| common tendinous ring | A fibrous ring that surrounds the optic canal and the medial part of the superior orbital fissure; it gives origin to the four rectus muscles of the eye and is partially fused with the sheath of the optic nerve. Synonym: annulus tendineus communis, Zinn's ligament, Zinn's ring, Zinn's tendon. (05 Mar 2000) |
| M ring | <biology, microbiology> Innermost (motor) ring of the bacterial flagellar base, located in the outer leaflet of the plasma membrane. It is this ring that is linked to the hook region (and thus to the flagellum itself) and that rotates. Composed of 16 or 17 subunits (one more or less than the S ring). (13 Nov 1997) |
| wimberger ring | <radiology> Dense rim of demineralised epiphysis seen in scurvy (12 Dec 1998) |
| mumps skin test antigen | A sterile suspension of killed mumps virus in isotonic sodium chloride solution, used to determine susceptibility to mumps or to confirm previous exposure. (05 Mar 2000) |
| conjunctival ring | A narrow ring at the junction of the periphery of the cornea with the conjunctiva. Synonym: annulus conjunctivae. (05 Mar 2000) |
| constriction ring | The equatorial ring of microfilaments that diminishes in diameter probably both by contraction and disassembly as cytokinesis proceeds. (18 Nov 1997) |
| contractile ring | The equatorial ring of microfilaments that diminishes in diameter probably both by contraction and disassembly as cytokinesis proceeds. (18 Nov 1997) |