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41.
A series of asymmetrical thio-bis-N-methylcarbamate derivatives were synthesised by combining 3,4-methylenedioxyphenyl N-methylcarbamate with different N-methylcarbamates. Some of these derivatives combined good insecticidal activity against the housefly with reduced acute oral toxicity to mice. The thio-bis-N-methylcarbamates obtained exhibited a lower anti-cholinesterase activity than the more toxic of the two carbamate moieties contained in each combination. The weak synergism of piperonyl butoxide on the insecticidal activity of the derivatives suggests the possibility of a self synergism phenomenon caused by the 3,4-methylenedioxyphenyl group. 相似文献
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Suzanne J. Clark Nicola P. Coward Glenn W. Dawson Ian F. Henderson Andrew P. Martin 《Pest management science》1995,44(4):381-388
Two related iron chelates, one toxic to slugs by ingestion, the other not, were introduced into the foregut of D. reticulatum. The subsequent movement and redistribution of the metal within the slug tissues was studied by labelling the chelates with the radioactive isotope 55Fe. In slugs which survived treatment approximately half of the 55Fe was voided in faeces. The iron retained became unevenly distributed, the highest concentration occurring in the digestive gland, irrespective of the chelate used. At high doses, slugs treated with tris(1-oxo-1,2-diazabutan-2-oxido)Fe(III) were fatally poisoned while those treated with the homologue, tris(1-oxo-1,2-diazaoctan-2-oxido)Fe(III) were not. Slugs killed by the toxic chelate consistently contained proportionally less iron in the digestive gland and proportionally more in the body wall and reproductive system. Dosing slugs already killed by carbon dioxide asphyxiation gave a similar pattern, suggesting that the greater mobility of the iron from the toxic chelate was not a function of the slugs' metabolism. 相似文献
45.
Clark GA 《Science (New York, N.Y.)》1999,283(5410):2029, 2031-2029, 2032
46.
Poloxalene as an Anti-Bloat Compound and Its Effect on Milk Yield and Composition 总被引:1,自引:0,他引:1
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Poloxalene, a nonionic surfactant, was fed to beef cattle on a legume ration or a high grain ration to observe its effect on bloat. It was also fed to lactating dairy cows to note any effect on yield or composition of milk.
Poloxalene was beneficial in the prevention of bloat with both legume and grain rations. It had no effect on per cent fat, protein, solids-not-fat, or yield of milk.
相似文献47.
48.
Equine Protozoal Myeloencephalitis: A Report of Two Cases From Western Canada 总被引:1,自引:1,他引:0
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![点击此处可从《The Canadian veterinary journal. La revue veterinaire canadienne》网站下载免费的PDF全文](/ch/ext_images/free.gif)
E. G. Clark H. G. G. Townsend N. T. McKenzie 《The Canadian veterinary journal. La revue veterinaire canadienne》1981,22(5):140-144
Two cases of nonsuppurative myeloencephalitis are reported which clinically and pathologically resemble equine protozoal myeloencephalitis. Lesions in both horses were associated with Toxoplasma-like organisms visible in microscopic sections. Clinical signs and lesions in one case primarily involved the brain and in the other case principally involved the spinal cord and associated meninges. Positive identification of the organisms was not achieved; however, the etiological agent is unlikely to be a species of Toxoplasma. Recently published studies suggest a species of Sarcocystis is involved. 相似文献
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Analysis of the electrocardiograms of 100 normal goats 总被引:3,自引:0,他引:3