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131.
S Chema S Waghela A D James T T Dolan A S Young W N Masiga A D Irvin G H Mulela L S Wekesa 《The Veterinary record》1986,118(21):588-589
132.
Phosphorothionate and phosphate degradation was investigated as a factor which could influence the tolerance of organochlorine compound-resistant and susceptible mosquitofish (Gambusia affinis) to parathion and methyl parathion. The greater toxicity of methyl parathion than parathion can be attributed in part to a higher rate of degradation of methyl paraoxon than paraoxon (7-fold), but not to any difference in phosphorothionate dearylation. Resistant fish possess higher levels of microsomal mixed-function oxidases which can degrade methyl parathion (1.3-fold); these higher levels could contribute to the increased methyl parathion tolerance by this population over the susceptible population. Environmentally induced tolerance to parathion in the resistant population may be the result of increased levels of parathion degradation by induced mixed-function oxidases which can dearylate parathion. The increased tolerance of either insecticide by the resistant population is not caused by degradation of the phosphates by phosphotriesterases. 相似文献
133.
134.
James W. Ticer Crispin P. Spencer Norman Ackerman 《Veterinary radiology & ultrasound》1980,21(1):12-17
ansitional cell urethral carcinoma in four female dogs is reported. Lesion distribution in the proximal two thirds of the urethra and the radiographic appearance with retrograde positive contrast urethrography were similar in each dog. The normally smooth longitudinal urethral striations were replaced by multiple small, poorly marginated intraluminal masses that resulted in a generalized moth-eaten appearance. Extension of contrast medium into the periurethral tissues also occurred. Retrograde urethrography, a simple diagnostic technic, aided in establishing a differential diagnosis in dogs that had urine retention and stranguria. 相似文献
135.
An improved method for the analysis of carbofuran residues and its metabolites in plant material has been developed. Critical evaluation of previously published methods has enabled the elimination of unnecessary procedures, and practical difficulties have been overcome or minimised without loss of sensitivity. Separate extraction of bound and non-bound residues is followed by clean-up by coagulation, preparation of a derivative with 1-fluoro-2,4-dinitrobenzene, and gas-liquid chromatography using a thermionic nitrogen-selective detector system. The method can be used in general screening for carbamates as well as analysis for specific carbamate pesticide residues. 相似文献
136.
Diana M. Fieldgate Carolyn S. James R. J. W. Byrde D. Woodcock 《Pest management science》1970,1(5):183-188
Members of series of 4-(cyclobutylalkyl, cyclohexylalkyl and benzylalkyl)-2,6-dinitrophenols were tested in a glasshouse against apple powdery mildew caused by Podosphaera leucotricha. Three series involving a cyclohexyl substituent separated from the phenolic nucleus by one, two or three methylene groups were of the same order of activity, but replacement of this substituent by a phenyl group in one case, resulted in a marked decrease in activity. Of a number of esters tested, none was significantly more active than the corresponding phenol. 相似文献
137.
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139.
A survey of sheep dipping in Scotland in 1978 showed that about 42 tonnes of organophosphorus and 17 tonnes of organochlorine insecticides were used to control ectoparasites. Information is presented about their pattern of use and about the disposal of surplus sheep dip and the empty containers. Six river pollution incidents involving sheep dips in 1978 are recorded. The main geographical areas affected by headfly (Hydrotaea irritans Fall.) and the measures taken against them are noted. 相似文献
140.
A method is presented which determines the bromide ion content of foodstuffs using a bromide specific ion electrode. For low levels of bromide (< 10 mg/kg) or for accurate work, bromide was extracted from the ground commodity with water and then separated from interfering compounds by ion-exchange chromatography before estimation. Alternatively, bromide ion can be estimated approximately by direct measurement on the aqueous extracts after heating to denature proteins. The method was checked against three standard methods of bromide estimation in foods, using wheat that had been repeatedly fumigated with methyl bromide. The equipment required is inexpensive and can be adapted for field use. The method has been used to determine the bromide and chloride contents that occur naturally in wheat, maize, copra, soya beans and sorghum. 相似文献