| all-or-nothing phenomenon | <physiology> Refers to the phenomenon where the strength of a nerve impulse is not dependent on the strength of the stimulus. Instead, there is a threshold level of stimulus strength that must be reached before the nerve will fire an impulse (at full capacity). Below the threshold, the nerve will not fire at all. <cardiology> It also refers to the same phenomenon observed in the heart muscle, which will either contract fully or not at all. <psychology> In studies of behaviour, it refers to the same phenomenon where a behavioural stimulus will either produce a complete response or no response at all. Also called all-or-nothing principle, all-or-none law, all-or-none responsiveness, etc. (15 Nov 1997) |
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| nothing | 1. Not anything; no thing (in the widest sense of the word thing); opposed to anything and something. "Yet had his aspect nothing of severe." (Dryden) 2. Nonexistence; nonentity; absence of being; nihility; nothingness. 3. A thing of no account, value, or note; something irrelevant and impertinent; something of comparative unimportance; utter insignificance; a trifle. "Behold, ye are of nothing, and your work of nought." (Is. Xli. 24) "'T is nothing, says the fool; but, says the friend, This nothing, sir, will bring you to your end." (Dryden) 4. <mathematics> A cipher; naught. Nothing but, only; no more than. To make nothing of. To make no difficulty of; to consider as trifling or important. "We are industrious to preserve our bodies from slavery, but we make nothing of suffering our souls to be slaves to our lusts." . Not to understand; as, I could make nothing of what he said. Origin: From no, a. + thing. Source: Websters Dictionary (01 Mar 1998) |
| per- | 1. <prefix> A prefix used to signify through, throughout, by, for, or as an intensive as perhaps, by hap or chance; perennial, that lasts throughout the year; perforce, through or by force; perfoliate, perforate; perspicuous, evident throughout or very evident; perplex, literally, to entangle very much. 2. <chemistry> Originally, denoting that the element to the name of which it is prefixed in the respective compounds exercised its highest valence; now, only that the element has a higher valence than in other similar compounds; thus, barium peroxide is the highest oxide of barium; while nitrogen and manganese peroxides, so-called, are not the highest oxides of those elements. (29 Oct 1998) |
| per anum | By or through the anus. Origin: L. (05 Mar 2000) |
| per capita rate | <epidemiology> A rate which is proportional to the number of individuals in a population. (05 Dec 1998) |
| per contiguum | In contiguity; denoting the mode by which an inflammation or other morbid process spreads into an adjacent contiguous structure. Origin: per-+ L. Contiguus, touching, fr. Tango, to touch (05 Mar 2000) |
| per continuum | In continuity; continuous; denoting the mode by which an inflammation or other morbid process spreads from one part to another through continuous tissue. Origin: per-+ L. Continuus, holding together, continuous, fr. Teneo, to hold (05 Mar 2000) |
| per orally | To take a medication by mouth. (09 Oct 1997) |
| per os | By or through the mouth, denoting a method of medication. Origin: L. (05 Mar 2000) |
| per primam | By first intention. See: healing by first intention. Origin: L. (05 Mar 2000) |
| per rectum | By or through the rectum, denoting a method of medication. Origin: L. (05 Mar 2000) |
| per saltum | at a leap; at one bound; not gradually or through different stages. Origin: L. (05 Mar 2000) |
| per tubam | Through a tube. Origin: L. (05 Mar 2000) |
| per vias naturales | Through the natural passages; e.g., denoting a normal delivery, as opposed to cesarean section, or the passage in stool of a foreign body instead of its surgical removal. Origin: L. (05 Mar 2000) |
| haemorrhage per rhexis | Haemorrhage due to the rupture of a blood vessel. (05 Mar 2000) |