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排序方式: 共有96条查询结果,搜索用时 314 毫秒
91.
在我国个人信用征信制度中,个人征信机构的所有经营活动都是围绕着消费者的个人信用信息展开的。因此,不可避免的存在着侵犯消费者隐私权的情形,必须在确保个人征信业的健康发展与隐私权的保护之间寻找一个平衡点。在借鉴世界各国对隐私权保护的基础上,针对我国立法和司法对隐私权保护的不足,提出了我国在现阶段保护隐私权的一些设想。 相似文献
92.
The dynamics of chromosome evolution in birds and mammals 总被引:20,自引:0,他引:20
Burt DW Bruley C Dunn IC Jones CT Ramage A Law AS Morrice DR Paton IR Smith J Windsor D Sazanov A Fries R Waddington D 《Nature》1999,402(6760):411-413
Comparative mapping, which compares the location of homologous genes in different species, is a powerful tool for studying genome evolution. Comparative maps suggest that rates of chromosomal change in mammals can vary from one to ten rearrangements per million years. On the basis of these rates we would expect 84 to 600 conserved segments in a chicken comparison with human or mouse. Here we build comparative maps between these species and estimate that numbers of conserved segments are in the lower part of this range. We conclude that the organization of the human genome is closer to that of the chicken than the mouse and by adding comparative mapping results from a range of vertebrates, we identify three possible phases of chromosome evolution. The relative stability of genomes such as those of the chicken and human will enable the reconstruction of maps of ancestral vertebrates. 相似文献
93.
Magnani F Mencuccini M Borghetti M Berbigier P Berninger F Delzon S Grelle A Hari P Jarvis PG Kolari P Kowalski AS Lankreijer H Law BE Lindroth A Loustau D Manca G Moncrieff JB Rayment M Tedeschi V Valentini R Grace J 《Nature》2007,447(7146):848-850
Temperate and boreal forests in the Northern Hemisphere cover an area of about 2 x 10(7) square kilometres and act as a substantial carbon sink (0.6-0.7 petagrams of carbon per year). Although forest expansion following agricultural abandonment is certainly responsible for an important fraction of this carbon sink activity, the additional effects on the carbon balance of established forests of increased atmospheric carbon dioxide, increasing temperatures, changes in management practices and nitrogen deposition are difficult to disentangle, despite an extensive network of measurement stations. The relevance of this measurement effort has also been questioned, because spot measurements fail to take into account the role of disturbances, either natural (fire, pests, windstorms) or anthropogenic (forest harvesting). Here we show that the temporal dynamics following stand-replacing disturbances do indeed account for a very large fraction of the overall variability in forest carbon sequestration. After the confounding effects of disturbance have been factored out, however, forest net carbon sequestration is found to be overwhelmingly driven by nitrogen deposition, largely the result of anthropogenic activities. The effect is always positive over the range of nitrogen deposition covered by currently available data sets, casting doubts on the risk of widespread ecosystem nitrogen saturation under natural conditions. The results demonstrate that mankind is ultimately controlling the carbon balance of temperate and boreal forests, either directly (through forest management) or indirectly (through nitrogen deposition). 相似文献
94.
TiAl合金高温拉伸流变应力与Zener-Hollomon因子的关系函数 总被引:4,自引:0,他引:4
:把温度T和应变速率ε·对Ti-47Al-2Mn-2Nb(TiAlMnNb)和Ti-47Al-2Mn-2Nb-0.8TiB2(TiAlMnNbB)合金在1073~1373K和10-5~10-1s-1条件范围内拉伸应力的影响归结为Zener-Hollomon因子Z=ε·exp(Q/RT)的影响,利用Sellars和Tegart提出的双曲函数,确定两种合金拉伸形变应力峰值σP与Z因子之间的关系函数;得到的σP解析表达式中A、α和n值分别为2.308×108s-1、8.50×10-9Pa-1和2.594(TiAlMnNb),1.423×1010s-1、6.275×10-9Pa-1和2.980(TiAlMnNbB);Z因子中的激活能Q值分别为322.3kJ/mol和351.6kJ/mol,提示两种合金高温拉伸形变受微观原子扩散过程控制 相似文献
95.
96.
Wang K Kan J Yuen ST Shi ST Chu KM Law S Chan TL Kan Z Chan AS Tsui WY Lee SP Ho SL Chan AK Cheng GH Roberts PC Rejto PA Gibson NW Pocalyko DJ Mao M Xu J Leung SY 《Nature genetics》2011,43(12):1219-1223
Gastric cancer is a heterogeneous disease with multiple environmental etiologies and alternative pathways of carcinogenesis. Beyond mutations in TP53, alterations in other genes or pathways account for only small subsets of the disease. We performed exome sequencing of 22 gastric cancer samples and identified previously unreported mutated genes and pathway alterations; in particular, we found genes involved in chromatin modification to be commonly mutated. A downstream validation study confirmed frequent inactivating mutations or protein deficiency of ARID1A, which encodes a member of the SWI-SNF chromatin remodeling family, in 83% of gastric cancers with microsatellite instability (MSI), 73% of those with Epstein-Barr virus (EBV) infection and 11% of those that were not infected with EBV and microsatellite stable (MSS). The mutation spectrum for ARID1A differs between molecular subtypes of gastric cancer, and mutation prevalence is negatively associated with mutations in TP53. Clinically, ARID1A alterations were associated with better prognosis in a stage-independent manner. These results reveal the genomic landscape, and highlight the importance of chromatin remodeling, in the molecular taxonomy of gastric cancer. 相似文献