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451.
452.
Sidney Bailey Geoffrey B. Collins F. Bernard Fishwick Harold V. Hart David F. Horler Keith A. Scudamore 《Pest management science》1982,13(4):373-378
Residue levels of organochlorine pesticides, organophosphorus pesticides, fumigants and bromide were determined in home-produced and imported wheat during the period October 1978 to April 1979. A total of 281 samples was analysed of which 133 contained low levels of carbon tetrachloride, 112 contained low levels of gamma-HCH and 26 contained low levels of malathion. One sample contained a residue of carbon tetrachloride, and another a residue of 1,2-dichloroethane, both of which were above the Codex Alimentarius guide-line levels. No other residue approached the proposed Codex Alimentarius maximum residue limits. 相似文献
453.
This paper provides information on the safety of ultrasonic diagnostic procedures as currently used in veterinary practice. The known mechanisms of action are described and selected literature on biological effects of ultrasound is reviewed. Current international consensus is presented on the safety of medical ultrasound with respect to thermal effects. To date, there is no independently verified clinical evidence that the level of exposure delivered to the tissues during scanned grey-scale (‘B-mode’) imaging has any adverse effects. Lung haemorrhage has been observed in animal experiments using diagnostic exposures, but the effects have not been reported in the foetus. Equipment that uses pulsed Doppler transmits higher acoustic outputs in a stationary beam, and can produce temperature increases that may have significant biological consequences. When considering sonographic and pulsed Doppler examinations of the prenatal animal, the safety margins are small and the operator should be aware of the acoustic output of the equipment, the exposure time, and the sensitivity of target tissues. 相似文献
454.
MASTITIS IN CATTLE CAUSED BY A MYCOPLASMA SP 总被引：1，自引：0，他引：1
455.
Fibrinogen levels in mammals suffering from bacterial infections 总被引：3，自引：0，他引：3
In a retrospective survey of fibrinogen levels and neutrophil counts in 388 blood samples from mammals suffering from bacterial infection, the combined results of the two tests provided positive confirmation of infection in a greater percentage of samples than did the results of either test alone. In Perissodactyla, Artiodactyla and Proboscidea, the fibrinogen level was abnormal more often than the neutrophil count. It was concluded that a fibrinogen estimation is a valuable addition to routine haematological screening procedures in mammals. 相似文献
456.
The stopped-flow technique has been applied to the determination of dissociation, phosphorylation, and bimolecular reaction constants for the inhibition of acetylcholinesterase by a potent organophosphate in the presence of a chromogenic substrate. The advantages of the method for inhibition studies are compared with those of an earlier spectrophotometric technique. 相似文献
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