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排序方式： 共有342条查询结果，搜索用时 15 毫秒
81.
MERRILL L. JOHNSON 《Growth and change》1988,19(2):56-74
This study focuses on the location of electrical machinery manufacturing in South Carolina, Georgia, Mississippi, and Alabama (with special attention given to the first three states), and the degree to which this industry is associated with labor environments attractive to firms in the late stage of the product cycle. Labor-environment variables were selected from published sources and then collapsed into principal components. County-level component scores were then correlated with selected electrical machinery employment variables. The analysis suggests that, with the possible exception of electronic components manufacturing, there has been no widespread locational response by electrical machinery manufacturing in these states to labor environments attractive to firms in the late stage of the product cycle. 相似文献
82.
K. A. JOHNSON D. B. CHURCH R. J. BARTON A. K. W. WOOD 《The Journal of small animal practice》1988,29(10):657-666
Rickets diagnosed in a 12-week-old female St Bernard was attributed to an inborn error in vitamin D metabolism. Radiographically the physes were enlarged radially and axially, and metaphyseal bone adjacent to the physes was widened and cup-shaped. Serum biochemical abnormalities were hypocalcaemia, hypomagnesaemia, and hyperparathyroidism. Treatment was given with dihydrotachysterol, a synthetic sterol that is metabolised to a pharmacologically active analogue of 1,25 dihydroxycholecalciferol by the liver. This resolved the rachitic skeletal lesions completely in six weeks, as assessed radiographically, and maintained the serum calcium at the lower end of the normal range. 相似文献
83.
SUMMARY Weaned lambs were infected with Haemonchus contortus 35,28,21,14 and 7 days after treatment with moxidectin at 0.2 mg/kg and 35 and 14 days after treatment with ivermectin at the same dose rate. Worm counts 14 days after infection showed that moxidectin prevented the establishment of over 99% of infective larvae for 28 days and reduced the establishment rate at 35 days by 96%, relative to ivermectin. There was no difference in the protective efficacy of ivermectin at 14 or 35 days. The persistence of moxidectin is likely to provide advantages in nematode control, particularly when used as a strategic early summer treatment or as a pre-lambing treatment to ewes. Implications of the persistent activity of moxidectin for the development of resistance during the decay phase are discussed. 相似文献
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