| radiotherapy dosage | The total amount of radiation absorbed by tissues as a result of radiotherapy. (12 Dec 1998) |
|---|---|
| gene dosage | <molecular biology> Number of copies of a particular gene locus in the genome, in most cases either one or two. (18 Nov 1997) |
| gene dosage compensation | The putative mechanism that adjusts the X-linked phenotypes of males and females to compensate for the haploid state in males and the diploid state in females. It is now largely ascribed to lyonization which compensates the mean of the dose but not its variance, which is greater in females. (05 Mar 2000) |
| gene dosage effect | In codominant alleles, the more or less linear relationship between the phenotypic value and the number of genes of one type substituted by another type. (05 Mar 2000) |
| dosage | The determination and regulation of the size, frequency and number of doses. (18 Nov 1997) |
| dosage compensation | <genetics> A genetic regulatory mechanism which operates to equalise the phenotypic expression of characteristics determined by genes on the x chromosome so that they are equally expressed in the xy male and the xx female. (12 Dec 1998) |
| dosage effect | The alteration of a phenotype by an increased dosage, or amount, of the product of the gene. (09 Oct 1997) |
| dosage forms | Completed forms of the pharmaceutical preparation in which prescribed doses of medication are included. They are designed to resist action by gastric fluids, prevent vomiting and nausea, reduce or alleviate the undesirable taste and smells associated with oral administration, achieve a high concentration of drug at target site, or produce a delayed or long-acting drug effect. They include capsules, liniments, ointments, pharmaceutical solutions, powders, tablets, etc. (12 Dec 1998) |
| dosage schedule | A scheme set up to determine and regulate size, frequency and number of doses. (18 Nov 1997) |
| abnormalities, radiation-induced | Congenital changes in the morphology of organs produced by exposure to ionizing or non-ionizing radiation. (12 Dec 1998) |
| accidents, radiation | Accidental dispersal of radioactive materials from a radiation source. Accidents at nuclear reactors can involve large groups of the population from dispersion of radioactivity into the environment and through fallout or a few individuals with high injurious doses. (12 Dec 1998) |
| acoustic radiation | The fibres that pass from the medial geniculate body to the transverse temporal gyri of the cerebral cortex by way of the sublentiform part of the internal capsule. Synonym: radiatio acustica. (05 Mar 2000) |
| acute radiation syndrome | <syndrome> A syndrome caused by exposure of the body to large amounts of radiation, (e.g., from certain forms of therapy, accidents, and nuclear explosions; it is divided into three major forms which are, in ascending order of severity, the haematogic, gastrointestinal, and central nervous system-cardiovascular forms; its clinical manifestations are divided into prodromal, latent, overt, and recovery stages. (05 Mar 2000) |
| adaptive radiation | <chemistry> The evolution of new speciesor sub-species to fill unoccupied ecological niches. (06 May 1997) |
| alpha radiation | <physics, radiobiology> The most easily absorbable type of radiation, it consists of a stream of alpha particles, doubly ionised helium nuclei which are electrically charged and produce intense ionisation in matter. Alpha radiation can be deflected in electromagnetic fields. (09 Oct 1997) |