| zero-order reaction | A reaction that proceeds at a particular rate independently of the concentration of the reactant or reactants. (05 Mar 2000) |
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| first-order kinetics | A term describing the reaction rate of a chemical reaction in which the rate is proportional to the concentration (in moles) of only one of the reactants. Such a reaction might have an equation like rate = k[A], where k is the reaction rate constant and [A] is the concentration of a reactant A. (09 Oct 1997) |
| first-order reaction | A reaction the rate of which is proportional to the concentration of the single substance undergoing change; radioactive decay is a first-order process, defined by the equation -(dN/dt)=kN, where N is the number of atoms subject to decay (reaction), t is time, and k is the first-order decay (reaction) constant, i.e., the fraction of all atoms decaying per unit of time. See: decay constant, order. (05 Mar 2000) |
| maximum | 1. The greatest possible or actual effect or quantity. 2. The acme of a disease or process. (18 Nov 1997) |
| maximum breathing capacity | The volume of air breathed when an individual breathes as deeply and as quickly as possible for a given time (e.g., 15 sec.). Synonym: maximum breathing capacity. (05 Mar 2000) |
| maximum occipital point | The point on the squama of the occipital bone farthest from the glabella. (05 Mar 2000) |
| maximum permissible dose | <radiobiology> Defined by the International Commission on Radiological Protection as the greatest dose of radiation which, in the light of present knowledge, is not expected to cause detectable bodily injury to a person at any time during his lifetime. This dose has been reduced with each Commission report. The MPD is given in terms of acute or chronic exposure of the whole body or of organs, systems, or regions of the body, and differs for persons who are occupationally exposed versus the public at large. (05 Mar 2000) |
| maximum permissible exposure level | The highest level of exposure to a substance, usually noxious, in the environment or during diagnostic and therapeutic procedures, that a body can tolerate without injury. (12 Dec 1998) |
| maximum temperature | In bacteriology, denoting a temperature above which growth will not take place. (05 Mar 2000) |
| maximum urea clearance | The urea clearance when the urine flow exceeds 2 ml/min; normal value is about 75 ml blood/min per 1.73 m2 body surface area. (05 Mar 2000) |
| maximum velocity | The maximum rate of an enzyme-catalyzed reaction that can be achieved by progressively increasing the substrate concentration at a given enzyme concentration; in cases of substrate inhibition, Vmax is an extrapolated value in the absence of such inhibition; Cf.: Michaelis-Menten equation. The maximum initial rate of shortening of a myocardial fibre that can be obtained under zero load; used to evaluate the contractility of the fibre. (05 Mar 2000) |
| maximum voluntary ventilation | The volume of air breathed when an individual breathes as deeply and as quickly as possible for a given time (e.g., 15 sec.). Synonym: maximum breathing capacity. (05 Mar 2000) |
| tubular maximum | transport maximum |
| absorbable surgical suture | A surgical suture material prepared from a substance that can be digested by body tissues and is therefore not permanent; it is available in various diameters and tensile strengths, and can be treated to modify its resistance to absorption and be impregnated with antimicrobial agents. (05 Mar 2000) |
| anastomosis, surgical | Surgical union or shunt between ducts, tubes or vessels. It may be end-to-end, end-to-side, side-to-end, or side-to-side. (12 Dec 1998) |