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41.
Structure of tumour necrosis factor 总被引:27,自引:0,他引:27
Tumour necrosis factor is a trimeric molecule, each subunit of which consists of an antiparallel beta-sandwich. Individual subunits from the trimer by a novel edge-to-face packing of beta-sheets. A comparison of the subunit fold with that of other proteins reveals a remarkable similarity to the 'jelly-roll' structural motif characteristic of viral coat proteins. 相似文献
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As some theorists regard organizational culture as ambiguities, this study attempts to prove that ambiguities are actually the resultant overview of interacting and dissimilar functional subcultures. Therefore, study of the effect of culture on performance should focus on the subculture system instead of the illusive and probably non-existing unitary corporate culture. To this end, a consensual structural framework that effectively demarcates the boundaries of subcultures is needed. By using the Viable System Model as a structural framework for the demarcation of functional subcultures, a questionnaire survey on construction professionals in Hong Kong was conducted. Statistical analysis results indicate that corporate culture could be better understood as a system of functional subcultures that correspond to the five functions of the viable system model. It is further noted that the strength of some functional subculture variables associates differently and significantly with organizational performance. 相似文献
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In the collection of Watt's papers at Doldowlod, home of Lord Gibson-Watt, there are seven previously unpublished letters from James Hutton to James Watt, and four letters from Watt to Hutton, also unpublished. The letters were written between 1774 and 1795. Very little of Hutton's other correspondence survives, so these letters add significantly to our knowledge. The earliest letters, together with two letters to George Clerk-Maxwell (in the Scottish Record Office), describe geological tours that Hutton made through Wales, the Midlands, and the south-west of England in 1774. The correspondence after 1774, which will appear in a later edition of Annals of Science, reveals Watt's expertise in geology, and also discusses meteorology, varnish making, Symington's steam engines, the first experiments with steam navigation, pneumatic medicine, and other topics. 相似文献
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Summary Disturbance to energy production in the S180 sarcoma (CB) by optical isomers of isoproterenol was assessed from altered adenine nucleotide levels at 1 h. The L-isomer almost halved the ATP level and lowered the energy charge significantly; the D-isomer was inactive. Dependence of tumor injury on cytochrome P-450 activity appears unlikely.One of us (GRNJ) thanks the Department of Surgery, Medical School, Kings's College Hospital, London, England, for the provision of experimental facilities; the Institute of Biochemistry, German Cancer Research Centre, Heidelberg, FRG, for permitting the measurement of metabolites; the Cancer Research Campaign, London, UK, for a part-time grant; and Zyma GmbH, München, FRG, and the estate of the late Dr Lucie Polak for additional financial support. 相似文献
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DNA mutagenesis and recombination 总被引:10,自引:0,他引:10
The polymerase chain reaction is used for site-specific mutagenesis and for DNA recombination without any enzymatic reaction in vitro, apart from DNA amplification. 相似文献
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Protein structure. Prediction of progress at last 总被引:4,自引:0,他引:4
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