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排序方式: 共有204条查询结果,搜索用时 312 毫秒
61.
GR MARTIN RJ SUTHERLAND† ID ROBERTSON† WE KIRKPATRICK DR KING PJ HOOD† 《Australian veterinary journal》1991,68(7):241-243
The toxicity of pindone, a rabbit poison, to horses, cattle, goats, chickens, dogs and cats was investigated, using extension of prothrombin time (PT) as an index of poisoning. The daily dose of pindone, administered for 5 days, ranged from 0.3 mg/kg for dogs to 2.5 mg/kg for chickens. This range of dose rates was considered to be indicative of the worst possible case that could arise following a campaign of baiting for rabbits. Although significant elevations in PT (more than double baseline values) were noted in all species other than horses, clinical signs of anticoagulant poisoning were not observed in any of the species tested. From the observed PT, cattle and cats appeared to be the most susceptible, and horses the least susceptible, to pindone toxicity. The half-lives of the elevated PT were calculated as 3.1 days for cattle, 2.8 days for goats and chickens, 1.9 days for horses and dogs and less than one day for cats. It is proposed that these half-lives can be used as a guide for determining the duration of treatment of pindone-affected animals. 相似文献
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67.
Tarascon JM Greene LH McKinnon WR Hull GW Geballe TH 《Science (New York, N.Y.)》1987,235(4794):1373-1376
Structural, magnetic, and electronic properties of compounds in the series La2-xSrx CuO4-y for 0.05 = x = 1.1, with deltax = 0.025, were studied. Resistance, susceptibility, Meissner, and shielding measurements have revealed superconductivity among several members of the series. For x = 0.15, the transition temperature T(c), measured at the midpoint of the resistive transition, is a maximum at 39.3 K with a width of 2 K. At other compositions the transition is broader and occurs at a lower temperature. Annealing the x = 0.15 sample in oxygen at 500 degrees C increases T(c) to 40.3 K, while annealing at the same temperature under vacuum suppresses the superconductivity. These changes in oxygen content and T(c) are reversible. 相似文献
68.
Hull GF 《Science (New York, N.Y.)》1945,101(2618):220-221
69.
Extrapolating species abundance across spatial scales 总被引:3,自引:0,他引:3
WE Kunin 《Science (New York, N.Y.)》1998,281(5382):1513-1515
The analysis, measurement, and management of species abundance is central to ecology and conservation biology, but it has proved difficult to find a single index that adequately reflects the commonness or rarity of species across a range of spatial scales. Here, a scale-independent measure of species abundance is developed, using presence-absence maps at varying spatial resolutions. By extrapolating such "scale-area" curves, species abundance can be estimated accurately even at scales finer than those used to parameterize the model, a task that had previously been deemed impossible in principle. 相似文献
70.
Oncogenicity of the simian adenoviruses 总被引:7,自引:0,他引:7
R N Hull I S Johnson C G Culbertson C B Reimer H F Wright 《Science (New York, N.Y.)》1965,150(699):1044-1046
Five of 17 adenoviruses of rhesus or cynomolgus monkey origin induced tumors in newborn hamsters. The tumors appeared between 42 and 280 days after subcutaneous inoculation and had the general characteristics of lymphomas. The tumors were specific by cross-complement fixation tests. An adenovirus recovered from Cercopithecus monkeys appeared to be highly oncogenic; all 23 inoculated hamsters developed tumors within 30 to 40 days. 相似文献