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11.
Biogeographical change in the tiger, Panthera tigris 总被引:2,自引:0,他引:2
12.
The purpose of this review is to provide a global perspective on Oncorhynchus salmonine introductions and put-and-take fisheries based on modern stocking programs, with special emphasis on freshwater
ecosystems. We survey the global introductions of nine selected salmonines of the genus Oncorhynchus: golden trout, cutthroat trout, pink salmon, chum salmon, coho salmon, masu/cherry salmon, rainbow trout/steelhead, sockeye
salmon/kokanee, and chinook salmon. The information is organized on a geographical basis by continent, and then by species
and chronology. Two different objectives and associated definitions of ‘success’ for introductions are distinguished: (a)
seed introduction: release of individuals with the purpose of creating a wild-reproducing, self-sustaining population; and
(b) put-and-take introduction: release of individuals with the purpose of maintaining some level of wild population abundance,
regardless of wild reproduction. We identify four major phenomena regarding global salmonine introductions: (1) general inadequacy
of documentation regarding introductions; (2) a fundamental disconnect between management actions and ecological consequences
of introductions; (3) the importance of global climate change on success of previous and future introductions; and (4) the
significance of aquaculture as a key uncertainty in accidental introductions. We conclude this review with a recognition of
the need to terminate ongoing stocking programs for introduced salmonines worldwide. 相似文献
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Andrew Strathern 《American anthropologist》1998,100(2):563-564
Bodytime: On the Interaction of Body, Identity, and Society. Susanne Lundin and Lynn Åkesson. eds. Lund, Sweden: Lund University Press, 1996. 196 pp. 相似文献
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Andrew J. Sutherland-Smith 《Biophysical reviews》2011,3(1):15-23
The cytoskeleton framework is essential not only for cell structure and stability but also for dynamic processes such as cell migration, division and differentiation. The F-actin cytoskeleton is mechanically stabilised and regulated by various actin-binding proteins, one family of which are the filamins that cross-link F-actin into networks that greatly alter the elastic properties of the cytoskeleton. Filamins also interact with cell membrane-associated extracellular matrix receptors and intracellular signalling proteins providing a potential mechanism for cells to sense their external environment by linking these signalling systems. The stiffness of the external matrix to which cells are attached is an important environmental variable for cellular behaviour. In order for a cell to probe matrix stiffness, a mechanosensing mechanism functioning via alteration of protein structure and/or binding events in response to external tension is required. Current structural, mechanical, biochemical and human disease-associated evidence suggests filamins are good candidates for a role in mechanosensing. 相似文献
18.
A hunter-killed wild turkey (Meleagris gallopavo silvestris) was submitted for examination because of numerous 2 to 30 mm diameter, yellowish, hard nodules in the skin. The nodules were confined to the skin and did not involve subcutaneous tissues. Nodules consisted of dilated feather follicles packed with a caseous tan to pale yellow material. Histologically, affected feather follicles were markedly dilated and filled with laminated keratin debris. The lesions were determined to be multiple feather follicle cysts of unknown etiology. 相似文献
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Summary Osteogenesis imperfecta (OI) is a phenotype with clinical and biochemical heterogeneity. We report here that expression of the OI phenotype extends to the level of dermal fibroblast morphology in vitro. Growth characteristics and morphology of control (n=6) and OI cell strains (n=10, representing the four major OI categories, Sillence classification) were compared by measuring the following: (i) days required in culture to reach confluence after plating at uniform density; (ii) cell density at confluence; (iii) width and length of cells (measured on phase contrast micrographs at 300xmagnification). Our results show that: (i) OI fibroblasts take longer (11–27 days, mean 20 days) than control cells (10–19 days, mean 16 days) to reach stationary phase; (ii) all OI phenotypes achieve a lower cell density (0.87x106 cells/P60, range 0.3–1.6x106) at stationary phase relative to control cells (2.2x106 cells/P60, range 1.7–2.6x106; F4,77=56.1, p<0.01, indicating that OI cells are larger than normal). Cell shape (expressed as the width: length ratio) was also abnormal in OI cells. (F4,730=37.6, p<0.01), types I and II OI cells have significantly increased ratios (p<0.01) relative to control, type III, and type IV cells. Intra-group phenotypic heterogeneity was also apparent in the OI categories and also within the control population. These findings confirm deviant morphologic phenotypes in OI dermal fibroblasts and further demonstrate interindividual heterogeneity in the expression of genes that determine size and shape of dermal fibroblasts in both OI and normal donors.Publication No. 84013 from the Montreal Children's Hospital Research Institute 相似文献