| RCC | radiological control center; rape crisis center; ratio of cost to charges; receptor-chemoeffector co... |
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| VOR | Vestibulo-Ocular Reflex |
| AOC | abridged ocular chart; amyloxycarbonyl; anodal opening contraction; area of concern |
| AROA | autosomal recessive ocular albinism |
| ASOD | anterior segmental ocular dysgenesis |
| salt-depletion crisis | Severe illness resulting from loss of sodium chloride, usually in urine (i.e., salt-losing nephritis), in sweat following severe exercise in hot weather, or in intestinal secretions, as in cholera. Can occur as result of Addison's disease or Addisonian crisis; characterised by hypovolaemia, hypotension. (05 Mar 2000) |
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| sickle cell crisis | <haematology> Disease common in races of people from areas in which malaria is endemic. The cause is a point mutation in the allele that codes for the beta chain of haemoglobin with a substitution of (valine for glutamic acid at position 6. The defective haemoglobin (HbS) crystallizes readily at low oxygen tension. In consequence, erythrocytes from homozygotes change from the normal discoid shape to a sickled shape when the oxygen tension is low and these sickled cells become trapped in capillaries or damaged in transit, leading to severe anaemia. In heterozygotes, the disadvantages of the abnormal haemoglobin are apparently outweighed by increased resistance to Plasmodium falciparum malaria, probably because parasitised cells tend to sickle and are then removed from circulation. Symptoms include joint pain, acute abdominal pain, and ulcerations of the lower extremities. Origin: Gr. Haima = blood (18 Nov 1997) |
| Dietl's crisis | Intermittent pain, sometimes with nausea and emesis, caused by intermittent proximal obstruction of ureter. Originally believed due to a mobile kidney that caused ureter to kink with positional changes. Synonym: incarceration symptom. (05 Mar 2000) |
| identity crisis | <psychology> Chaotic concept of self wherein one's role in life appears to be an insoluble dilemma often expressed by isolation, withdrawal, rebellion and extremism. (12 Dec 1998) |
| tabetic crisis | A sudden paroxysmal intensification of symptoms in the course of a disease. Origin: L., Gr. Krisis (18 Nov 1997) |
| therapeutic crisis | A turning point leading to positive or negative change in psychiatric treatment. (05 Mar 2000) |
| thyroid crisis | Sudden and dangerous increase of the symptoms of thyrotoxicosis. (12 Dec 1998) |
| thyrotoxic crisis | Thyroid crisis, the exacerbation of symptoms that occurs in severe thyrotoxicosis; can follow shock or injury or thyroidectomy; marked by rapid pulse (140 to 170 per minute), nausea, diarrhoea, fever, loss of weight, extreme nervousness, and a sudden rise in the metabolic rate; coma and death may occur; occasionally the entire clinical picture is that of profound prostration, weakness, and collapse, without the phase of muscular overactivity and tachycardia. Synonym: thyroid storm. (05 Mar 2000) |
| febrile crisis | The stage in a febrile disease when spontaneous defervescence occurs. (05 Mar 2000) |
| laryngeal crisis | An attack of paralysis of the abductor, or spasm of the adductor, muscles of the larynx with dyspnea and noisy respiration, occurring in tabetic neurosyphilis. (05 Mar 2000) |
| accommodation, ocular | The dioptric adjustment of the eye (to attain maximal sharpness of retinal imagery for an object of regard) referring to the ability, to the mechanism, or to the process. It is the effecting of refractive changes by changes in the shape of the crystalline lens. Loosely, it refers to ocular adjustments for vision at various distances. (12 Dec 1998) |
| adaptation, ocular | The adjustment of the eye to variations in the intensity of light. Light adaptation is the adjustment of the eye when the light threshold is increased; dark adaptation when the light is greatly reduced. (12 Dec 1998) |
| albinism, ocular | Albinism affecting the eye in which pigment of the hair and skin is normal or only slightly diluted. The classic type is x-linked (nettleship-falls), but an autosomal recessive form also exists. Ocular abnormalities may include reduced pigmentation of the iris, nystagmus, photophobia, strabismus, and decreased visual acuity. (12 Dec 1998) |
| anterior ocular segment | That portion of the eye comprising the cornea, iris, lens, and their associated chambers and adnexa. (05 Mar 2000) |
| cardinal ocular movements | Eye rotations to the right and left, upward to the right and left, and downward to the right and left, to diagnose positions of gaze. (05 Mar 2000) |