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41.
Saenz HL Engel P Stoeckli MC Lanz C Raddatz G Vayssier-Taussat M Birtles R Schuster SC Dehio C 《Nature genetics》2007,39(12):1469-1476
The bacterial genus Bartonella comprises 21 pathogens causing characteristic intraerythrocytic infections. Bartonella bacilliformis is a severe pathogen representing an ancestral lineage, whereas the other species are benign pathogens that evolved by radial speciation. Here, we have used comparative and functional genomics to infer pathogenicity genes specific to the radiating lineage, and we suggest that these genes may have facilitated adaptation to the host environment. We determined the complete genome sequence of Bartonella tribocorum by shotgun sequencing and functionally identified 97 pathogenicity genes by signature-tagged mutagenesis. Eighty-one pathogenicity genes belong to the core genome (1,097 genes) of the radiating lineage inferred from genome comparison of B. tribocorum, Bartonella henselae and Bartonella quintana. Sixty-six pathogenicity genes are present in B. bacilliformis, and one has been lost by deletion. The 14 pathogenicity genes specific for the radiating lineage encode two laterally acquired type IV secretion systems, suggesting that these systems have a role in host adaptability. 相似文献
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Alpha-MSH, beta-MSH and ACTH have been localized in the cells of hypophyseal intermediate lobe by fluorescence histoimmunological technics. Elaboration and excretion of these polypeptides are enhanced after dehydration or adrenalectomy. The most evident variations are seen with alpha-MSH and ACTH after dehydration, with beta-MSH after adrenalectomy. 相似文献
45.
In this paper, Cassava dregs are an outgrowth produced during starchy production which uses cassava as raw material. It is usually dropped out or used as cheap feedstuff. In order to make the best use of cassava dregs, increase industries' benefits and reduce castoffthis study developed a 'new technique which used cassava dregs as raw material to produce distilled spirits based on cassava dregs characteristics. The technique adopt solid-ferment procedure. At first, the ferment is processed by solid-state distilling, and then rectification extra care refinement; at last the tequila was produced with characteristics of simple and elegant fragrance and mellow-tasting. 相似文献
46.
Albane le Maire William Bourguet Patrick Balaguer 《Cellular and molecular life sciences : CMLS》2010,67(8):1219-1237
Endocrine-disrupting chemicals (EDCs) represent a broad class of exogenous substances that cause adverse effects in the endocrine
system by interfering with hormone biosynthesis, metabolism, or action. The molecular mechanisms of EDCs involve different
pathways including interactions with nuclear hormone receptors (NHRs) which are primary targets of a large variety of environmental
contaminants. Here, based on the crystal structures currently available in the Protein Data Bank, we review recent studies
showing the many ways in which EDCs interact with NHRs and impact their signaling pathways. Like the estrogenic chemical diethylstilbestrol,
some EDCs mimic the natural hormones through conserved protein–ligand contacts, while others, such as organotins, employ radically
different binding mechanisms. Such structure-based knowledge, in addition to providing a better understanding of EDC activities,
can be used to predict the endocrine-disrupting potential of environmental pollutants and may have applications in drug discovery. 相似文献
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针对空间网架螺栓节点球在特定的分度夹紧装置上进行自动编程数控加工的过程 ,讨论了加工过程中夹紧信息的识别与提取 ,并以数学语言加以描述 ,有利于用计算机语言编程 ,实现螺栓节点球数控加工过程中夹紧状态判别的自动化 相似文献
49.
全国普通高校体育教育专业体操比赛的调查研究 总被引:2,自引:0,他引:2
通过对全国普通高校体育教育专业体操团体比赛成绩的统计分析,认为各校运动队以良好的运动竞技表演接受了国家教育部的检查,深化了体育教学改革,并对存有不足提出相应的建议。 相似文献
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Zhu P Liu J Bess J Chertova E Lifson JD Grisé H Ofek GA Taylor KA Roux KH 《Nature》2006,441(7095):847-852
Envelope glycoprotein (Env) spikes on AIDS retroviruses initiate infection of host cells and are therefore targets for vaccine development. Though crystal structures for partial Env subunits are known, the structure and distribution of native Env spikes on virions is obscure. We applied cryoelectron microscopy tomography to define ultrastructural details of spikes. Virions of wild-type human immunodeficiency virus 1 (HIV-1) and a mutant simian immunodeficiency virus (SIV) had approximately 14 and approximately 73 spikes per particle, respectively, with some clustering of HIV-1 spikes. Three-dimensional averaging showed that the surface glycoprotein (gp120) 'head' of each subunit of the trimeric SIV spike contains a primary mass, with two secondary lobes. The transmembrane glycoprotein 'stalk' of each trimer is composed of three independent legs that project obliquely from the trimer head, tripod-like. Reconciling available atomic structures with the three-dimensional whole spike density map yields insights into the orientation of Env spike structural elements and possible structural bases of their functions. 相似文献