| targeted drug delivery | Delivering a drug to a specific site in the body where it has the greatest effect, instead of allowing it to diffuse to various sites, where it may cause damage or trigger side effects. (14 Nov 1997) |
|---|---|
| radiation therapy | <radiobiology> Treatment with high energy radiation from X-rays or other sources of radiation. (16 Dec 1997) |
| photodynamic radiation therapy | <oncology, technique> A light sensitive drug is given through a vein and concentrates in the tumour. Then, during a surgical procedure, a special light activates the drug. The activated drug kills tumour cells. (31 Dec 1997) |
| internal radiation therapy | Radiation therapy in which radioactive material is placed in or near a tumour. (12 Dec 1998) |
| interstitial radiation therapy | <oncology> The implantation of radioactive seeds directly into a tumour. (10 Jan 1998) |
| intraoperative radiation therapy | Treating a tumour site withradiation immediately following surgery to destroy the tumour. (09 Oct 1997) |
| external radiation therapy | Radiation therapy using a machine located outside the body to aim high-energy rays at a tumour. (12 Dec 1998) |
| 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) |
| annihilation radiation | The radiation resulting when a positron from beta positive decay comes to rest. It encounters an electron, and they annihilate each other and convert their rest mass into two 0.51-MeV gamma rays emitted in exactly opposite directions. (05 Mar 2000) |
| background radiation | <radiobiology> Level of environmental radation due to background sources. Background sources can be natural, such as cosmic rays and natural radioactive elements (principally radon, but including other elements such as isotopes of potassium (which people get substantial amounts of in foods like bananas)). They can also be man-made, such as from fossil-fuel combustion, everyday leakage from nuclear activities, and leftover from atmospheric nuclear weapons tests. Background radiation is usually distinguished from acute radiation, such as from medical X-rays, nuclear accidents, radioisotope therapy, or other short-term doses. The man-made contribution to background radiation is quite small compared to the natural contribution, medical uses dominate human exposure to acute radiation. (09 Oct 1997) |