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排序方式: 共有1002条查询结果,搜索用时 15 毫秒
921.
We report relatively high trehalase activity in amniotic fluid of a fetus affected with the autosomal recessive type of polycystic kidney disease (type II), suggesting that prenatal detection of this condition could be done on this basis in conjunction with ultrasonography. 相似文献
922.
We report relatively high trehalase activity in the amniotic fluid of two fetuses affected with the congenital nephrotic syndrome of the Finnish type. The results suggest that prenatal detection of this condition can be done on this basis in conjunction with the α-fetoprotein and acetylcholinesterase tests in amniotic fluid. 相似文献
923.
Ana Marçalo Luísa Mateus José Henrique Duarte Correia Pedro Serra Rob Fryer Yorgos Stratoudakis 《Marine Biology》2006,149(6):1509-1518
Observations from the purse seine fishery off northern Portugal are used to describe the early dynamics of sardine (Sardina pilchardus) stress reactions and identify likely stressors during the commercial fishing operation. Sardine blood and muscle were sampled from the onset of fishing (school identification and encircling) to the end of fish transfer onboard (90–120 min later). The evolution of haematocrit, haemoglobin, cortisol, glucose, ionic concentrations, ATP and its catabolites were modelled using linear mixed models as a function of time spent in the net, biological (sex, reproductive state and condition) and operational variables (catch, light level and phase of fishing operation). Significant linear trends with time were detected for most stress variables and mean concentrations after 2 h in the net were similar to literature values corresponding to acute stress reactions for teleosts. Biological variables were rarely significant and explained a small proportion of variation, while operational variables were never significant. For each stress variable, levels varied considerably between trips but the temporal evolution was common across trips. Random trip effects were uncorrelated among most biochemical variables, suggesting that distinct factors affected each stress variable during the sampled trips. However, the linear trend with time spent in the net observed for most stress variables indicates that the duration of the fishing operation is an important stressor in purse seine fishing due to the progressive water volume restriction, crowding and manipulation associated to the fishing method. 相似文献
924.
Samples of Echinarachnius parma (Lamarck), collected during summer 1988 from three sites along the eastern coast of Canada (the northern Gulf of St. Lawrence, Chaleur Bay and the Bay of Fundy), showed sexual dimorphism in the shape of the oral surface in addition to marked changes in the camber of the aboral surface related to the strength of wave and current activity. The oral surface is more concave in males than in females. The dimorphism develops as individuals become sexually mature and is pronounced for individuals measuring >4 cm in diameter. Associated with this shape difference, the volume of females is greater than for males, and this corresponds to the larger size attained by the ovaries compared to the testis. Shape differences between males and females are rare in echinoderms, and E. parma is the first species for which the sexes can be separated with a high degree of accuracy (>80%) on the basis of shape. 相似文献
925.
Annie‐Claude Parent François Anctil Véronique Cantin Marie‐Amélie Boucher 《Journal of the American Water Resources Association》2008,44(3):679-688
Abstract: Snowmelt largely affects runoff in watersheds in Nordic countries. Neural networks (NN) are particularly attractive for streamflow forecasting whereas they rely at least on daily streamflow and precipitation observations. The selection of pertinent model inputs is a major concern in NNs implementation. This study investigates performance of auxiliary NN inputs that allow short‐term streamflow forecasting without resorting to a deterministic snowmelt routine. A case study is presented for the Rivière des Anglais watershed (700 km2) located in Southern Québec, Canada. Streamflow (Q), precipitations (rain R and snow S, or total P), temperature (T) and snow lying (A) observations, combined with climatic and snowmelt proxy data, including snowmelt flow (QSM) obtained from a deterministic model, were tested. NN implemented with antecedent Q and R produced the largest gains in performance. Introducing increments of A and T to the NNs further improved the performance. Long‐term averages, seasonal data, and QSM failed to improve the networks. 相似文献
926.
Francesca Romana Grati Denise Molina Gomes Jose Carlos Pinto B. Ferreira Celine Dupont Viola Alesi Laetitia Gouas Nina Horelli-Kuitunen Kwong Wai Choy Sandra García-Herrero Alberto Gonzalez de la Vega Krzysztof Piotrowski Rita Genesio Gloria Queipo Barbara Malvestiti Bérénice Hervé Brigitte Benzacken Antonio Novelli Philippe Vago Kirsi Piippo Tak Yeung Leung Federico Maggi Thibault Quibel Anne Claude Tabet Giuseppe Simoni François Vialard 《黑龙江环境通报》2015,35(8):801-809
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