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1.
Aquatic environmental impact associated with stream-crossing by a pipeline was monitored at Archibald Creek, B.C. for two years. Water chemistry and benthic macroinvertebrates were used as monitoring tools. Results indicated that impacts arising from stream-crossing were short-term and non-residual.Funded by a contract from Canadian Arctic Gas Study Limited, calgary, to Aquatic Environments Limited, Calgary.Aquatic Environments Limited, Calgary.Aquatic Environments Limited, Calgary. 相似文献
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Molecular basis of growth cone adhesion: anchoring of adheron- containing filaments at adhesive loci 下载免费PDF全文
Adhesive contacts made by filopodia of neuronal growth cones are essential for proper neurite elongation and may have a role in the formation of synaptic junctions. Previously we described the appearance of filamentous materials extending from growth cone surfaces that seem to be associated with the strongly adhesive behavior of filopodia (Tsui, H.-C., K. L. Lankford, and W. L. Klein. 1985. Proc. Natl. Acad. Sci. USA. 82:8256-8260). Here, we have used immunogold labeling to determine whether known adhesive molecules might be localized at points of adhesion and possibly be constituents of the filamentous material. Antibodies to an adhesive molecule (neural cell adhesion molecule [N-CAM]) and to an adhesive macromolecular complex of proteins and proteoglycans (adheron) were localized at the EM level in whole mounts of cultured avian retina cells. Labeling of fixed cells showed that N-CAM and adheron molecules were both present on growth cones and on filopodia. However, filamentous materials extending from the cell surface were labeled with anti-adheron but not with anti-N-CAM. If cells were labeled before fixation, patches of anti-N-CAM labeling occurred in random areas over the growth cones, but adheron antibodies concentrated at points of apparent adhesion. Particularly dense clustering of anti-adheron occurred at individual filopodial tips and at points of contact between pairs of filopodia. The different patterns of labeling imply that N-CAMS do not associate with the main antigenic components of adheron on the membrane surface. Most importantly, the data indicate the N-CAMs were mobile in the membrane but that constituents of adherons were anchored at adhesive loci. An appealing hypothesis is that molecules found in adheron preparations have an important role in establishing the adhesive junctions formed by growth cone filopodia. 相似文献
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S W Scherer G Otulakowski B H Robinson L C Tsui 《Cytogenetics and cell genetics》1991,56(3-4):176-177
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Localization of a beta-crystallin gene, Hu beta A3/A1 (gene symbol: CRYB1), to the long arm of human chromosome 17 总被引:3,自引:0,他引:3
M L Law G Y Cai J Hartz F T Kao D Hogg M L Breitman L C Tsui 《Cytogenetics and cell genetics》1986,42(4):202-207
We have assigned a human beta-crystallin gene, Hu beta A3/A1 (gene symbol: CRYB1), to chromosome 17 using a panel of 19 human-hamster somatic cell hybrids and blot-hybridization analysis of cell hybrid DNA. Positive probe-hybridization signal was detected in a hybrid that had lost the short arm of human chromosome 17 but retained the long arm, translocated to a hamster chromosome. In addition, in situ hybridization analysis of metaphase chromosome spreads of this cell line suggested that the most probable location for CRYB1 is on the long arm of chromosome 17, in the region q21. 相似文献
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Correction of the cystic fibrosis defect in vitro by retrovirus-mediated gene transfer. 总被引:54,自引:0,他引:54
M L Drumm H A Pope W H Cliff J M Rommens S A Marvin L C Tsui F S Collins R A Frizzell J M Wilson 《Cell》1990,62(6):1227-1233