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Black's veterinary dictionary 21st edition - XYZ

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Từ điển thú y vần XYZ | X X-Rays are high-energy radiation capable of passing through considerable thicknesses of many substances which are opaque to ordinary light without undergoing material absorption but other substances even in very small thicknesses are able to absorb the great majority of the rays thus flesh is very transparent healthy bone is fairly opaque. Widely used for diagnostic imaging of internal body structures and in human medicine for radiotherapy. Precautions Guard screens of lead glass rubber impregnated with lead or sheet lead are used to protect the operators of radiographic apparatus and precautions are necessary to shield the testes and ovaries of young persons and animals from the sterilising effects of the rays. Detailed precautions are as follows 1. Persons under 16 years must not take part in radiological procedures. 2. Fluoroscopy imaging or radiotherapy should not be carried out except under expert radiological guidance. Hand-held fluoroscopes must not be used in any circumstances. 3. Personnel radiation monitoring devices such as film badges must be worn by all persons who take part routinely in radiological procedures. 4. The animal should if possible be anaesthetised or tranquillised for radiography and all persons should withdraw as far as practicable from the useful beam. 5. If it should be necessary to hold the animal for radiography lead-protective gloves and aprons must be worn. Whenever possible holding should be done by the owners unless they are under 16 years or pregnant. 6. Persons should not expose any part of their bodies to the useful beam even when wearing protective clothing. 7. The useful beam should be restricted to the area being examined by means of a beamlimiting device. Notes on protection against radiation will also be found in the British Veterinary Association s guide to the Health and Safety at Work Act. Regulations In the UK the Ionising Regulations 1985 require veterinary surgeons using X-ray equipment to notify their local .