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排序方式: 共有1069条查询结果,搜索用时 15 毫秒
81.
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Climate impact of increasing atmospheric carbon dioxide 总被引:2,自引:0,他引:2
Hansen J Johnson D Lacis A Lebedeff S Lee P Rind D Russell G 《Science (New York, N.Y.)》1981,213(4511):957-966
The global temperature rose by 0.2 degrees C between the middle 1960's and 1980, yielding a warming of 0.4 degrees C in the past century. This temperature increase is consistent with the calculated greenhouse effect due to measured increases of atmospheric carbon dioxide. Variations of volcanic aerosols and possibly solar luminosity appear to be primary causes of observed fluctuations about the mean trend of increasing temperature. It is shown that the anthropogenic carbon dioxide warming should emerge from the noise level of natural climate variability by the end of the century, and there is a high probability of warming in the 1980's. Potential effects on climate in the 21st century include the creation of drought-prone regions in North America and central Asia as part of a shifting of climatic zones, erosion of the West Antarctic ice sheet with a consequent worldwide rise in sea level, and opening of the fabled Northwest Passage. 相似文献
84.
Russell PF 《Science (New York, N.Y.)》1933,78(2014):101-102
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86.
Implantation of genetically engineered fibroblasts into mice: implications for gene therapy 总被引:7,自引:0,他引:7
R F Selden M J Skoskiewicz K B Howie P S Russell H M Goodman 《Science (New York, N.Y.)》1987,236(4802):714-718
In a variety of human genetic diseases, replacement of the absent or defective protein provides significant therapeutic benefits. As a model for a somatic cell gene therapy system, cultured murine fibroblasts were transfected with a human growth hormone (hGH) fusion gene and cells from one of the resulting clonal lines were subsequently implanted into various locations in mice. Such implants synthesized and secreted hGH, which was detectable in the serum. The function of the implants depended on their location and size, and on the histocompatibility of the donor cells with their recipients. The expression of hGH could be modified by addition of regulatory effectors, and, with appropriate immunosuppression, the implants survived for more than 3 months. This approach to gene therapy, here termed "transkaryotic implantation," is potentially applicable to many genetic diseases in that the transfected cell line can be extensively characterized prior to implantation, several anatomical sites are suitable for implantation, and regulated expression of the gene of therapeutic interest can be obtained. 相似文献
87.
Diphosphonates inhibit formation of calcium phosphate crystals in vitro and pathological calcification in vivo 总被引:14,自引:0,他引:14
Two diphosphonates containing the P-C-P bond, CH(3)C(OH)(PO(3)HNa)(2) and H(2)C(PO(3)HNa)(2), inhibit the crystallization of calcium phosphate in vitro and prevent aortic calcification of rats given large amounts of vitamin D(3). The diphosphonates therefore have effects similar to those described for compounds containing the P-O-P bond but are active when administered orally. 相似文献
88.
Direct measurements of intracellular K(+) and Cl(-)activities before and after blockage of cellular metabolic processes indicate that K(+) is actively transported inwardly and Cl(-)is actively transported outwardly from the giant cell of the abdominal ganglion of Aplysia. The rewarming of cells that have been cooled to 1 degrees +/- 1 degrees C causes K(+) to be taken up and Cl(-) to be extruded against electrochemical gradients. 相似文献
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Nadeau JH Balling R Barsh G Beier D Brown SD Bucan M Camper S Carlson G Copeland N Eppig J Fletcher C Frankel WN Ganten D Goldowitz D Goodnow C Guenet JL Hicks G Hrabe de Angelis M Jackson I Jacob HJ Jenkins N Johnson D Justice M Kay S Kingsley D Lehrach H Magnuson T Meisler M Poustka A Rinchik EM Rossant J Russell LB Schimenti J Shiroishi T Skarnes WC Soriano P Stanford W Takahashi JS Wurst W Zimmer A;International Mouse Mutagenesis Consortium 《Science (New York, N.Y.)》2001,291(5507):1251-1255