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排序方式: 共有277条查询结果,搜索用时 15 毫秒
71.
Chin K de Solorzano CO Knowles D Jones A Chou W Rodriguez EG Kuo WL Ljung BM Chew K Myambo K Miranda M Krig S Garbe J Stampfer M Yaswen P Gray JW Lockett SJ 《Nature genetics》2004,36(9):984-988
Transition through telomere crisis is thought to be a crucial event in the development of most breast carcinomas. Our goal in this study was to determine where this occurs in the context of histologically defined breast cancer progression. To this end, we assessed genome instability (using fluorescence in situ hybridization) and other features associated with telomere crisis in normal ductal epithelium, usual ductal hyperplasia, ductal carcinoma in situ and invasive cancer. We modeled this process in vitro by measuring these same features in human mammary epithelial cell cultures during ZNF217-mediated transition through telomere crisis and immortalization. Taken together, the data suggest that transition through telomere crisis and immortalization in breast cancer occurs during progression from usual ductal hyperplasia to ductal carcinoma in situ. 相似文献
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OPCML at 11q25 is epigenetically inactivated and has tumor-suppressor function in epithelial ovarian cancer 总被引:12,自引:0,他引:12
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76.
Jiang Hui 《科学通报(英文版)》2007,52(6):789-796
Diatom data from core MD992271 on the North Icelandic shelf record a cooling trend through the last 3000 years. This is indicated by a general decrease in warm water species and an increase in cold water taxa. The relative abundance of these two diatom groups changed periodically, suggesting that the climate also fluctuated within this time period. The results of diatom-based transfer function calculation show that the summer sea-surface temperatures (SSTs) before 1400 cal. a BP were generally higher than the mean value for the last 3000 years and the summer SSTs fluctuated around the mean between 1400 and 700 cal. a BP, and dropped to the values below the mean after 700 cal. a BP. Four cooling events were distinguished, centered at around 2600, 1900, 1300 and 600 cal. a BP respectively. The results are not only consistent with the data from neighbouring cores HM107-03 and MD992275, but also comparable with those from the GISP2 ice core and from other marine sediment records in the North Atlantic. This suggests that changes in the summer SSTs reflect regional climate variations in the North Atlantic. On the North Icelandic shelf, the summer SST variation is a result of changes in the in-teraction between the cold and the warm currents in the area. 相似文献
77.
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
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
78.
Eleonora Dondossola Anna Gasparri Angela Bachi Renato Longhi Marie-Hélène Metz-Boutigue Bruno Tota Karen B. Helle Flavio Curnis Angelo Corti 《Cellular and molecular life sciences : CMLS》2010,67(12):2107-2118
Fibroblast adhesion can be modulated by proteins released by neuroendocrine cells and neurons, such as chromogranin A (CgA)
and its N-terminal fragment vasostatin-1 (VS-1, CgA1–78). We have investigated the mechanisms of the interaction of VS-1 with fibroblasts and of its pro-adhesive activity and have
found that the proadhesive activity of VS-1 relies on its interaction with the fibroblast membrane via a phospholipid-binding
amphipathic α-helix located within residues 47–66, as well as on the interaction of the adjacent C-terminal region 67–78,
which is structurally similar to ezrin–radixin–moesin-binding phosphoprotein 50 (a membrane-cytoskeleton adapter protein),
with other cellular components critical for the regulation of cell cytoskeleton. 相似文献
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Croker B Crozat K Berger M Xia Y Sovath S Schaffer L Eleftherianos I Imler JL Beutler B 《Nature genetics》2007,39(12):1453-1460
Specific homeostatic mechanisms confer stability in innate immune responses, preventing injury or death from infection. Here we identify, from a screen of N-ethyl-N-nitrosourea-mutagenized mice, a mutation causing both profound susceptibility to infection by mouse cytomegalovirus and approximately 20,000-fold sensitization to lipopolysaccharide (LPS), poly(I.C) and immunostimulatory (CpG) DNA. The LPS hypersensitivity phenotype is not suppressed by mutations in Myd88, Trif, Tnf, Tnfrsf1a, Ifnb, Ifng or Stat1, genes contributing to LPS responses, and results from an abnormality extrinsic to hematopoietic cells. The phenotype is due to a null allele of Kcnj8, encoding Kir6.1, a protein that combines with SUR2 to form an ATP-sensitive potassium channel (K(ATP)) expressed in coronary artery smooth muscle and endothelial cells. In Drosophila melanogaster, suppression of dSUR by RNA interference similarly causes hypersensitivity to infection by flock house virus. Thus, K(ATP) evolved to serve a homeostatic function during infection, and in mammals it prevents coronary artery vasoconstriction induced by cytokines dependent on TLR and/or MDA5 immunoreceptors. 相似文献