- 1. The performance of any of the vital functions, the manner of such performance, or the result of the same. 2. The exertion of any force or power, physical, chemical, or mental. [L. actio, from ago, pp. actus, to do]- ball valve a. intermittent blockage of a tube or outlet of a cavity by some object or material that permits passage in one direction but not in the other.- calorigenic a. increase of heat production of the body, as by the thyroid hormone. SYN: thermogenic a..- salt a. any physicochemical effect produced by hypertonic concentrations of osmotically active electrolytes.- sparing a. the manner in which a nonessential nutritive component, by its presence in the diet, lowers the dietary requirement for an essential component; thus, nonessential l-cysteine spares essential l-methionine and nonessential l-tyrosine spares essential l-phenylalanine. SYN: sparing phenomenon.- specific a. the a. of a drug or a method of treatment which has a direct and especially curative effect upon a disease, e.g., the a. of vitamin B12 in pernicious anemia.- specific dynamic a. (SDA) increase of heat production caused by the ingestion of food, especially of protein.- thermogenic a. SYN: calorigenic a..* * *A Coronary Disease Trial Investigating Outcome with Nifedipine GITS; Assisting Carriers Using Telematics Interventions to Meet Older Persons Needs [Ireland]
* * *ac·tion 'ak-shən n1) the process of exerting a force or bringing about an effect that results from the inherent capacity of an agent <protein synthesis is an expression of gene \action> <insecticidal \action>2) a function or the performance of a function of the body (as defecation) or of one of its parts <the normal baby has three or four \actions of the bowel in 24 hours (Morris Fishbein)> <heart \action>3) an act of will
* * *ac·tion (akґshən) [L. actio] any performance of function or movement either of any part or organ or of the whole body.
Medical dictionary. 2011.