| RSC | rat spleen cell; rested state contraction; reversible sickle-cell; right subclavian |
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| S/b | sickle cell beta-thalassemia |
| SC | conditioned stimulus; sacrococcygeal; Sanitary Corps; scalenus [muscle]; scapula; Schwann cell; scia... |
| S-C | sickle cell |
| SCA | self-care agency; severe congenital anomaly; sickle-cell anemia; single-camera autostereoscopic [ima... |
| sickle cell trait | <haematology> This condition occurs in people who have one of two possible genes (i.e., they are heterozygous forthe allele) that code for the defective haemoglobin responsible for sickle cell anaemia. The coditionis diagnosed by exposing an individual's red blood cells to a low oxygen environment, if the trait is present, the cells will turn to a sickle shape. People with this trait may suffer milder symptoms of sickle cell anaemia, or may have no symptoms. Some scientists believe the trait actually provides an evolutionary advantage in tropical environments because the slightly altered shape of the blood cells causes a person to be more resistant to malaria. (09 Oct 1997) |
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| sickle flap | A sickle-shaped flap from the anterior scalp and one side of the forehead, based on the opposite temporal artery. (05 Mar 2000) |
| sickle form | The male or female gametocyte(s) of Plasmodium falciparum, whose presence in human red blood cells is diagnostic of falciparum malaria. Synonym: crescent, sickle form. Myopic crescent, a white or grayish white crescentic area in the fundus of the eye located on the temporal side of the optic disk; caused by atrophy of the choroid, permitting the sclera to become visible. Synonym: myopic conus. Sublingual crescent, the crescent-shaped area on the floor of the mouth formed by the lingual wall of the mandible and the adjacent part of the floor of the mouth. (05 Mar 2000) |
| absolute scotoma | A scotoma in which there is no perception of light. (05 Mar 2000) |
| annular scotoma | A circular scotoma surrounding the centre of the field of vision. See: ring scotoma. (05 Mar 2000) |
| arcuate scotoma | A scotoma extending from the blind spot and arching into the nasal field following the lines of retinal nerve fibres. (05 Mar 2000) |
| Bjerrum's scotoma | A comet-shaped scotoma, occurring in glaucoma, attached at the temporal end to the blind spot or separated from it by a narrow gap; the defect widens as it extends above and nasally curves around the fixation spot, and then extends downward to end exactly at the nasal horizontal meridian. Synonym: Bjerrum's sign, sickle scotoma. (05 Mar 2000) |
| caecocentral scotoma | A scotoma involving the optic disk area (blind spot) and the papillomacular fibres; there are three forms: 1) the caecocentral defect which extends from the blind spot toward or into the fixation area; 2) angioscotoma; 3) glaucomatous nerve-fibre bundle scotoma, due to involvement of nerve-fibre bundles at the edge of the optic disk. See: Bjerrum's scotoma, Ronne's nasal step. (05 Mar 2000) |
| paracentral scotoma | A scotoma adjacent to the fixation point. (05 Mar 2000) |
| glaucomatous nerve-fibre bundle scotoma | See: caecocentral scotoma. (05 Mar 2000) |
| relative scotoma | A scotoma in which there is visual depression but not complete loss of light perception. (05 Mar 2000) |
| central scotoma | A scotoma involving the fixation point. (05 Mar 2000) |
| mental scotoma | Absence of insight into, or inability to comprehend, items relative to a subject whose content is highly emotional to the individual. Synonym: blind spot. (05 Mar 2000) |
| pericentral scotoma | A scotoma that surrounds the fixation point more or less symmetrically. (05 Mar 2000) |
| peripheral scotoma | A scotoma outside of the central 30 degrees of the visual field. (05 Mar 2000) |