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该报告运用文献计量学方法,对英国及其主要合作伙伴国的国际合作格局做了全面的分析。所选
择的主要国家包括美国、加拿大、法国、德国、日本、澳大利亚、中国与印度;数据覆盖领域有临床、医药
卫生、生物科学、环境科学、数学、物质科学以及工程技术领域;数据时间分为1996-2000年与2001-2005
年两个时间段。结果显示:国际论文数量增长显著;英国国际合作论文份额的增长比G7 国家更加快速; 德
国和美国是英国最大的国际合作伙伴;英国国际合作论文的平均影响力显著高于其科研论文的总体影响力;
中国与英国合作发表的论文数量超过了与其他欧洲各国的合作论文数。  相似文献   
2.
Long SB  Casey PJ  Beese LS 《Nature》2002,419(6907):645-650
Protein farnesyltransferase (FTase) catalyses the attachment of a farnesyl lipid group to numerous essential signal transduction proteins, including members of the Ras superfamily. The farnesylation of Ras oncoproteins, which are associated with 30% of human cancers, is essential for their transforming activity. FTase inhibitors are currently in clinical trials for the treatment of cancer. Here we present a complete series of structures representing the major steps along the reaction coordinate of this enzyme. From these observations can be deduced the determinants of substrate specificity and an unusual mechanism in which product release requires binding of substrate, analogous to classically processive enzymes. A structural model for the transition state consistent with previous mechanistic studies was also constructed. The processive nature of the reaction suggests the structural basis for the successive addition of two prenyl groups to Rab proteins by the homologous enzyme geranylgeranyltransferase type-II. Finally, known FTase inhibitors seem to differ in their mechanism of inhibiting the enzyme.  相似文献   
3.
Hsu GW  Ober M  Carell T  Beese LS 《Nature》2004,431(7005):217-221
Aerobic respiration generates reactive oxygen species that can damage guanine residues and lead to the production of 8-oxoguanine (8oxoG), the major mutagenic oxidative lesion in the genome. Oxidative damage is implicated in ageing and cancer, and its prevalence presents a constant challenge to DNA polymerases that ensure accurate transmission of genomic information. When these polymerases encounter 8oxoG, they frequently catalyse misincorporation of adenine in preference to accurate incorporation of cytosine. This results in the propagation of G to T transversions, which are commonly observed somatic mutations associated with human cancers. Here, we present sequential snapshots of a high-fidelity DNA polymerase during both accurate and mutagenic replication of 8oxoG. Comparison of these crystal structures reveals that 8oxoG induces an inversion of the mismatch recognition mechanisms that normally proofread DNA, such that the 8oxoG.adenine mismatch mimics a cognate base pair whereas the 8oxoG.cytosine base pair behaves as a mismatch. These studies reveal a fundamental mechanism of error-prone replication and show how 8oxoG, and DNA lesions in general, can form mismatches that evade polymerase error-detection mechanisms, potentially leading to the stable incorporation of lethal mutations.  相似文献   
4.
国际合作研究不仅可以利用其他国家的科研投资,而且能够产生具有轰动效应的创新型结果。由
于语言文化的相似性,英国与美国及欧洲国家有着较为广泛的联系,他们之间的合作是英国科学研究合作的
主体。随着科学研究及技术革新的发展更多地转向东方,以及中国和印度这两大科技力量的迅猛发展,英国
应该更加重视与这两个国家的合作。文章指出:应该就英国及其新伙伴之间的关系进行详细的研究,从而深
入理解中英两国间的合作并建立成功的合作模式。  相似文献   
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