| FWHM | full width at half maximum |
|---|---|
| H1/2 | half-value layer |
| HE | half-scan with extrapolation; hard exudate; hektoen enteric [agar]; hemagglutinating encephalomyelit... |
| hf | half; high frequency |
| HI | half-scan with interpolation; head injury; health insurance; hearing impaired; heart infusion; hemag... |
| life expectancy | <epidemiology> Longevity, the average length of life of individuals in a population. (05 Dec 1998) |
|---|---|
| life instinct | The instinct of self-preservation and sexual procreation; the basic urge toward preservation of the species. Synonym: sexual instinct. (05 Mar 2000) |
| life stress | Events or experiences that produce severe strain, e.g., failure on the job, marital separation, loss of a love object. (05 Mar 2000) |
| life support care | Care provided patients requiring extraordinary therapeutic measures in order to sustain and prolong life. (12 Dec 1998) |
| life support systems | Systems that provide all or most of the items necessary for maintaining life and health. Provisions are made for the supplying of oxygen, food, water, temperature and pressure control, disposition of carbon dioxide and body waste. The milieu may be a spacecraft, a submarine, or the surface of the moon. In medical care, usually under hospital conditions, life support care is available. (12 Dec 1998) |
| life table | A representation of the probable years of survivorship of a defined population of subjects; since survivorship is changed by new methods of prevention or treatment, a diachronic study is commonly used because the main interest lies in the composite structure of the current population. (In the summarizing technique used to describe the pattern of mortality and survival in a population, survivors to age x are denoted by the symbol lx and the expectation of life at age x is denoted by the symbol x. (05 Mar 2000) |
| life tables | Summarizing techniques used to describe the pattern of mortality and survival in populations. These methods can be applied to the study not only of death, but also of any defined endpoint such as the onset of disease or the occurrence of disease complications. (12 Dec 1998) |
| biological | Pertaining to biology. (18 Nov 1997) |
| biological agent | <microbiology> A disease-causing microorganism or virus, or other toxic biological matter, which is used as a weapon during war. (21 Mar 1998) |
| biological assay | <technique> Once a pharmaceutical protein is isolated from the cells in which it was grown, researchers perform tests to measure the protein's biological activity. It must maintain a certain minimal level of biological activity to be used for animal or clinical testing or, later, for market. Researchers also test to confirm that the isolated protein is identical to the desired protein. (21 Mar 1998) |
| biological assessment | A specific process required as part of an environmental assessment. An evaluation of potential effects of a proposed project on proposed, endangered, threatened, and sensitive animal and plant species and their habitats. (05 Dec 1998) |
| biological availability | The extent to which the active ingredient of a drug dosage form becomes available at the site of drug action or in a biological medium believed to reflect accessibility to a site of action. (12 Dec 1998) |
| biological chemistry | The scientific study of the chemistry of living cells, tissues, organs and organisms. (09 Oct 1997) |
| biological clock | <biology, physiology> An internal biological mechanism which controls certain biological rhythms and biocycles, such as metabolism, sleep cycles, photosynthesis. (21 Mar 1998) |
| biological clocks | The physiological mechanisms that govern the rhythmic occurrence of certain biochemical, physiological, and behavioural phenomena in plants and animals. The pineal gland, which receives input from the optic nerves and connects to the hypothalamus, may be the biological clock in humans. (12 Dec 1998) |