| EPR | early progressive resistance; electron paramagnetic resonance; electronic patient record; electrophr... |
|---|---|
| PR | by way of the rectum [Lat. per rectum]; far point [of accommodation] [Lat. punctum remotum]; palindr... |
| PVR | peripheral vascular resistance; perspective volume rendering; poliovirus receptor; postvoiding resid... |
| RVR | reduced vascular response; renal vascular resistance; repetitive ventricular response; resistance to... |
| TPR | temperature, pulse, and respiration; testosterone production rate; third party reimbursement; total ... |
natural purification (자정 작용
| natural language processing | Computer processing of a language with rules that reflect and describe current usage rather than prescribed usage. (12 Dec 1998) |
|---|---|
| natural mutation | A mutation which occurs by itself without first being affected by a mutagen, for example during the process of DNA replication. Spontaneous mutations arise at a remarkably constant rate. The rate that spontaneous mutations arise has been used as an evolutionary clock to estimate how closely related two (or more) separate species are to each other. (09 Oct 1997) |
| natural passive immunity | Immunity conferred by the mother on the foetus or newborn. (14 Nov 1997) |
| natural pigment | A naturally occurring coloured compound; absorbs light in the visible range of the electromagnetic spectrum. Compare: structural colour. Synonym: biochrome. (05 Mar 2000) |
| natural products | Naturally occurring compounds that are end products of secondary metabolism; often, they are unique compounds for particular organisms or classes of organisms. (05 Mar 2000) |
| natural selection | The hypothesis that genotype environment interactions occurring at the phenotypic level lead to differential reproductive success of individuals and hence to modification of the gene pool of a population. (18 Nov 1997) |
| immunity, natural | The capacity of a normal organism to remain unaffected by microorganisms and their toxins. It results from non-specific mechanisms such as genetic endowment, naturally occurring antiviral and bactericidal substances, phagocytosis, and constitutional factors such as body temperature, oxygen tension, and age. (12 Dec 1998) |
| killer cells, natural | Cells responsible for spontaneous cytotoxicity of a variety of tumour cells without prior immunization. These natural killer cells are found in non-immune humans and experimental animals and are thought by some to be the same as killer cells (killing by antibody-dependent cell cytotoxicity), but they can also kill in the absence of antibody. (12 Dec 1998) |
| airway resistance | The opposition of the tracheobronchial tree to air flow: the mouth-to-alveoli pressure difference divided by the air flow. (12 Dec 1998) |
| ampicillin resistance | Nonsusceptibility of a microbe to the action of ampicillin, a penicillin derivative that interferes with cell wall synthesis. (12 Dec 1998) |
| androgen resistance syndromes | A class of disorders associated with 5a-steroid reductase deficiency, testicular feminization, and related disorders. Compare: steroid 5a-reductase, Reifenstein's syndrome, infertile male syndrome, testicular feminization syndrome. (05 Mar 2000) |
| antibiotic resistance | The ability of a bacterium tosynthesise a protein that neutralises an antibiotic. (09 Oct 1997) |
| antibiotic resistance gene | Genes in a microorganism which confer resistance to antibiotics, for example by coding for enzymes which destroy it, by coding for surface proteins which prevent it from entering the microorganism, or by being a mutant form of the antibiotic's target so that it can ignore it. (09 Oct 1997) |
| bacteriophage resistance | Resistance of a bacterial mutant to infection by a bacteriophage to which the parent (wild type) strain is susceptible. (05 Mar 2000) |
| beta-lactam resistance | Nonsusceptibility of an organism to the action of the beta-lactam antibiotics. (12 Dec 1998) |