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排序方式: 共有71条查询结果,搜索用时 15 毫秒
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ELIZABETH M. HARDIE DVM RONALD J. KOLATA DVM MS DipACVS THOMAS D. EARLEY DVM MS CLARENCE A. RAWLINGS DVM PhD DipACVS EDWARD J. GORGACZ VMD PhD 《Veterinary surgery : VS》1983,12(2):69-72
A technique that utilizes transposition of the internal obturator muscle for repair of perineal hernias was evaluated. Forty-two male dogs were followed for at least one year after surgery. The repair failed in only one animal, a dog with previously operated bilateral hernias. Microangiography demonstrated an adequate blood supply to the transposed internal obturator muscles of two dogs examined at three weeks and three months after surgery. 相似文献
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A total of 474 pregnancy tests (of all three types) were carried out on 82 bitches of a variety of breeds. The practical problems and possible sources of error for each test were studied and their accuracy in predicting whether or not the bitches would whelp was ascertained. Palpation of the abdomen, in the period from 26 to 35 days after mating, was found to be 87% accurate in detecting bitches that would whelp and 73% accurate in detecting bitches that would not whelp. The optimum period for using A-mode ultrasound was found to be from 32 to 62 days after mating. In this period the accuracy of detecting bitiches that would whelp was 90%, and for non-whelping bitches was 83%. Two Doppler ultrasound instruments were used. For the superior instrument, the accuracy of detecting whelping bitches was 85% and 100%, in the periods from 36 to 42 days and 43 days to term, respectively. For detection of non-whelping bitches, the accuracy was 100%. 相似文献
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A method is described for investigating radiographically the shape of the bitch's vagina. The intra-pelvic vagina is readily dilated whereas the intra-abdominal vagina is narrow and tortuous, and cranially is typically ‘spoon-shaped’. Contrast medium entered the uterus during pro-oestrus, oestrus and the post-partum period, indicating patency of the cervix at these times. No cervical relaxation was evident at the end of the luteal phase, i.e. during anoestrus. The possible relevance of these findings to the aetiology of pyometra is discussed. 相似文献
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Physical and biological consequences of a climate event in the central North Pacific 总被引:4,自引:0,他引:4
JEFFREY J. POLOVINA GARY T. MITCHUM NICK E. GRAHAM MITCHELL P. CRAIG EDWARD E. DEMARTINI ELIZABETH N. FLINT 《Fisheries Oceanography》1994,3(1):15-21
Climatic changes over the North Pacific which began in the mid 1970s, peaked in the early 1980s, and ended by the late 1980s, appear to have altered productivity at various trophic levels in the marine ecosystem in the central North Pacific. The climatic change resulted in increased mixed layer depth and the frequency of deep mixing events, particularly during January-March. A number of biological time series for species ranging from primary to apex levels in the North-western Hawaiian Islands, show corresponding declines in productivity of 30–50% from the early 1980s to the present. We hypothesize that during the early 1980s, increased mixing due to the climate event resulted in greater nutrient input into the euphotic zone and ultimately increased ecosystem productivity. Productivity over a range of trophic levels declined when the climate event ended. 相似文献
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Using data from a survey of directors of not-for-profit industrial development groups in the United States and from a variety of secondary sources, we test the hypothesis that the presence of an active industrial development group was a significant factor in the economic growth of its service area over the 1977-to-1982 period. The data permit us to control for different levels of organizational resources among growth promotion groups as well as other traditional factors of local economic change in a regression analysis. While growth promotion groups are judged to be effective in terms of the number of jobs that are created or preserved relative to their direct expenditures of resources, neither their presence nor the levels of their organizational resources are significantly related to service area net employment change. The efforts of growth promotion groups are simply overwhelmed in importance by factors such as population size, metropolitan accessibility, location in a growth region, and manufacturing wage rates that characterize the respective service areas. 相似文献
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Mohamed EL‐SHEHABY Mohamed Sayed SALAMA Elisabeth BRUNNER Jürgen HEINZE 《Integrative zoology》2011,6(3):259-265
Discrimination between nestmates and non‐nestmates in social insects is thought to rely on the pattern of cuticular hydrocarbons. We investigated the cuticular hydrocarbon profiles of 2 parapatric sibling ant species, Temnothorax nylanderi (Förster, 1850) and Temnothorax crassispinus (Karavaiev, 1926), and their hybrid. We found that although the profiles show considerable similarities, a discriminant analysis based on the relative peak areas of cuticular hydrocarbons separates the 3 taxa. The profiles of hybrids were not consistently intermediate between those of the paternal species, suggesting either non‐additive interactions among the parental biosynthetic pathways or systematic differences in environment‐derived odor cues. 相似文献
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Soil samples obtained from genetic horizons of an upland and acid sulphate soil of Sierra Leone, were equilibrated with 0.01 M CaCI using a 1:2 soil to solution ratio. Al3+ activity was estimated from total Al measured in the equilibrium extract, by accounting for hydrolysis and the formation of other complex species. The Al3+ activity was pH-dependent, but the Al(OH)3 ion product was I'airly constant throughout the upland soil profile; Al3+ activity was near that expected for equilibrium with kaolinite and quartz. In the acid sulphate soil alunite appeared to control the activity of Al3+. 相似文献