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a condition sometimes seen in patients who have received therapeutic doses of radiation. Its severity varies according to factors such as the individual's physical condition, the body areas exposed, and the amount, kind, and intensity of the exposure. The disease may be so slight that it is scarcely noticeable, or it may cause severe symptoms. Modern techniques and increased knowledge about radiation have lowered the incidence of severe radiation sickness. Systemic reactions to radiation include a general feeling of malaise, loss of appetite or nausea and vomiting, and headache. The symptoms tend to subside when the therapy is discontinued, leaving no permanent effect on the patient.
a systemic condition caused by substantial whole-body irradiation, seen after nuclear explosions or accidents, rarely after radiotherapy. Manifestations depend on dosage, ranging from anorexia, nausea, vomiting, and mild leukopenia, to thrombocytopenia with hemorrhage, severe leukopenia with infection, anemia, central nervous system damage, and death.
Synonym(s): radiation poisoning
Illness induced by exposure to ionizing radiation, ranging in severity from nausea, vomiting, headache, and diarrhea to loss of hair and teeth, reduction in red and white blood cell counts, extensive hemorrhaging, sterility, and death.
an abnormal condition resulting from exposure to ionizing radiation. The severity of the condition is determined by the intensity of radiation, the length of time of exposure, and the area of the body affected. Moderate exposure may cause headache, nausea, vomiting, anorexia, and diarrhea; long-term exposure may result in sterility, fetal damage in pregnant women, leukemia or other forms of cancer, alopecia, and cataracts.
radiation sicknessThe generic term for the constellation of findings associated with exposure to high doses of ionising radiation.
ra·di·a·tion sick·ness(rā'dē-ā'shŭn sik'nĕs)
A systemic condition caused by substantial whole-body irradiation, seen after nuclear explosions or accidents, more rarely after radiotherapy. Manifestations depend on dose, ranging from anorexia, nausea, vomiting, and mild leukopenia to thrombocytopenia with hemorrhage, severe leukopenia with infection, anemia, central nervous system damage, and death.
radiation sicknessThe effects of major doses of ionizing RADIATION on the whole body. The symptoms and rapidity of onset depend on the dose taken. They include nausea and vomiting, bloody diarrhoea, bleeding into the skin, the effects of severe ANAEMIA, hair loss and sterility. Very large doses, of 30 to 100 GRAY, cause rapid onset of abdominal symptoms with anxiety, disorientation, coma and death within a few days from damage to the nervous system. Radiation sickness is caused by the production of large numbers of damaging FREE RADICALS.
ra·di·a·tion sick·ness(rā'dē-ā'shŭn sik'nĕs)
Systemic condition caused by substantial whole-body irradiation, seen after nuclear explosions or accidents, but rarely after radiotherapy. Manifestations depend on dosage.
1. divergence from a common center.
2. a structure made up of diverging elements, especially a tract of the central nervous system made up of diverging fibers.
3. energy carried by waves or a stream of particles. One type is electromagnetic radiation, which consists of wave motion of electric and magnetic fields. The quantum theory is based on the fact that electromagnetic waves consist of discrete particles, called photons, that have an energy inversely proportional to the wavelength of the wave. In order of increasing photon energy and decreasing wavelength, the electromagnetic spectrum is divided into radio waves, infrared light, visible light, ultraviolet light and x-rays.
Another type is the radiation emitted by radioactive materials. Alpha particles are high-energy helium-4 nuclei consisting of two protons and two neutrons, which are emitted by radioisotopes of heavy elements, such as uranium. Beta particles are high-energy electrons, which are emitted by radioisotopes of lighter elements. Gamma rays are high-energy photons, which are emitted along with alpha and beta particles and are also emitted alone by metastable radionuclides, such as technetium-99m. Gamma rays have energies in the x-ray region of the spectrum and differ from x-rays only in that they are produced by radioactive decay rather than by x-ray machines.
Radiation with enough energy to knock electrons out of atoms and produce ions is called ionizing radiation. This includes alpha and beta particles and x-rays and gamma rays.
study of the effects of ionizing radiation on living tissues.
particles emitted in nuclear disintegration, including alpha and beta particles, protons, neutrons, positrons and deuterons.
special equipment, including Geiger-Müller tubes and a scintillation crystal, is available to detect radiation which may be accidental, or detect small amounts where this is expected but it needs to be measured in terms of accumulated dose.
energy, unassociated with matter, that is transmitted through space by means of waves (electromagnetic waves) traveling in all instances at 3 × 1010 cm or 186,284 miles per second, but ranging in length from 1011 cm (electrical waves) to 10−12 cm (cosmic rays) and including radio waves, infrared, visible light and ultraviolet, x-rays and gamma rays.
means more than the patient being exposed intentionally to an x-ray beam. Technical persons in the vicinity will also be exposed to a much less dangerous but perniciously cumulative load of radiation.
the portion of the spectrum of electromagnetic radiation of wavelengths ranging between 0.75 and 1000 μm. See also infrared.
is caused by exposure to radioactive material. High doses cause intense diarrhea and dehydration and extensive skin necrosis. Median doses cause initial anorexia, lethargy and vomiting then normality for several weeks followed by vomiting, nasal discharge, dysentery, recumbency, septicemia and a profound pancytopenia. Death is the most common outcome. Chronic doses cause cataract in a few. Congenital defects occur rarely.
energy emitted by radium or radon inserted directly into the tissue.
corpuscular or electromagnetic radiation that is capable of producing ions, directly or indirectly, in its passage through matter. Used in treatment of radiosensitive cancer, in sterilization of animal products and food for experimental use.
the person responsible for the administration of radiation therapy including estimating the dose required for a treatment, arranging for the dose to be delivered and making arrangements for safety of the patient and staff, and disposing of any residual radioactive material. Technical aspects of the work include computer estimations, preparation of isodose curves, preparation of wedge and compensating filters, and calibration of teletherapy equipment.
radiation emanating from the x-ray tube which is absorbed by the subject or passes on through the subject without any change in photon energy.
includes proper control of emissions from the x-ray machines, proper protective clothing for staff, keeping unnecessary people out of the way while the tube is actually generating its beam, the wearing and regular examination of a dosimeter and the proper storage of radioactive materials or residues.
fibers extending from the pyramidal tract to the cortex.
tissues vary in their sensitivity to the damaging effects of irradiation. The rapidly growing tissues are most susceptible, e.g. the embryo, rapidly growing cancer, gonads, alimentary tract, skin and blood-forming organs.
see radiation injury (above).
a fiber system joining the thalamus and the hypothalamic region.
fibers radiating laterally from the nucleus ruber.
fibers streaming out through the lateral surface of the thalamus, through the internal capsule to the cerebral cortex.
a person skilled in radiotherapy. See also radiation therapy (below).
the portion of the spectrum of electromagnetic radiation of wavelengths ranging between 0.39 and 0.18 μm. See also ultraviolet rays.