| ALARA | as low as reasonably achievable [radiation exposure] |
|---|---|
| BEAR | biological effects of atomic radiation |
| BEIR | biological effects of ionizing radiation |
| CCRT | computer-controlled radiation therapy |
| CRE | cumulative radiation effect; cyclic adenosine monophosphate-response element |
| ultraviolet radiation | <physics> Invisible light, next to visible light in the electromagnetic spectrum. The most common source of ultraviolet radiation is the sun. Acronym: UV (16 Dec 1997) |
|---|---|
| K-radiation | Usually a very penetrating form of x-radiation excited by cathode rays (high speed electrons) impinging upon a metal anode such as tungsten; the energy of the radiation is a function of the binding energy of the K-shell electrons of the metal anode. (05 Mar 2000) |
| L-radiation | An x-radiation of slight penetrating power excited by cathode rays (high speed electrons) impinging on a metal anode; the energy of the radiation is a function of the binding energy of the L-shell electrons of the metal anode. (05 Mar 2000) |
| abdomen, acute | Clinical syndrome characterised by abdominal pain of great severity associated with other symptoms and signs, usually those of acute peritonitis, which might well be the result of a ruptured abdominal viscus or a similar abdominal catastrophe requiring urgent surgical operation. (12 Dec 1998) |
| acute | 1. Sharp, poignant. 2. Having a short and relatively severe course. Origin: L. Acutus = sharp (18 Nov 1997) |
| acute abdomen | Any serious acute intra-abdominal condition (such as appendicitis) attended by pain, tenderness, and muscular rigidity, and for which emergency surgery must be considered. Synonym: surgical abdomen. (05 Mar 2000) |
| acute abscess | A recently formed abscess with little or no fibrosis in the wall of the cavity. Synonym: hot abscess. (05 Mar 2000) |
| acute adrenal crisis | <endocrinology> An abrupt life-threatening state which is caused by insufficient production of cortisol by the adrenal gland. A typical finding in Addison's disease. Individuals who have been taking corticosteroids (glucocorticoids) for a prolonged period of time (weeks to months) are at risk for acute adrenal crisis if the medication is stopped abruptly. For this reason, corticosteroid medication are withdrawn slowly on a diminishing dosing schedule. Symptoms include low blood pressure (shock), weakness, headache, vomiting, fever chills, tachycardia and sweating. Treatment includes blood pressure support and intravenous hydrocortisone. (27 Sep 1997) |
| acute adrenocortical insufficiency | Severe adrenocortical insufficiency when an intercurrent illness or trauma causes an increased demand for adrenocortical hormones in a patient with adrenal insufficiency due to disease or use of relatively large amounts of similar hormones as therapy; characterised by nausea, vomiting, hypotension, and frequently hyperthemia, hyponatraemia, hyperkalaemia, and hypoglycaemia; can be fatal if untreated. Synonym: addisonian crisis, adrenal crisis, Bernard-Sergent syndrome. (05 Mar 2000) |
| acute alcoholism | A temporary deterioration in mental function, accompanied by muscular incoordination and paresis, induced by the rapid ingestion of alcoholic beverages. Synonym: intoxication. (05 Mar 2000) |
| acute angle | Any angle less than 90 |
| acute angle closure glaucoma | <ophthalmology> An increase in pressure within the anterior chamber of the eye. There are two forms of glaucoma: acute angle closure and open angle glaucoma. (27 Sep 1997) |
| acute anterior poliomyelitis | Inflammation of the anterior cornua of the spinal cord; an acute infectious disease caused by the poliomyelitis virus and marked by fever, pains, and gastroenteric disturbances, followed by a flaccid paralysis of one or more muscular groups, and later by atrophy. Synonym: acute atrophic paralysis, myogenic paralysis. (05 Mar 2000) |
| acute aortic dissection | <cardiology> A condition in which a weakened portion of the thoracic aorta begins to tear along the longitudinal axis of the vessel. Symptoms include sudden, severe chest pain that may radiate to the back accompanied by nausea, sweating and difficulty breathing. A common risk factor for this event is atherosclerotic vascular disease and-or hypertension. Advanced cases of syphilis (syphilitic aortitis) can also result in acute thoracic dissection as a complication of infection with Treponema pallidum. (27 Sep 1997) |
| acute appendicitis | Acute inflammation of the appendix, usually due to bacterial infection, which may be precipitated by obstruction of the lumen by a fecalith; symptoms of periumbilical colicky pain and vomiting are followed by fever, leukocytosis, persistent pain, and signs of peritoneal inflammation in the right lower quadrant of the abdomen; perforation or abscess formation is a frequent complication. (05 Mar 2000) |