首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   253篇
  免费   2篇
  国内免费   2篇
系统科学   9篇
理论与方法论   1篇
现状及发展   54篇
研究方法   45篇
综合类   139篇
自然研究   9篇
  2021年   1篇
  2020年   1篇
  2019年   2篇
  2018年   7篇
  2017年   3篇
  2016年   5篇
  2015年   4篇
  2014年   2篇
  2013年   3篇
  2012年   12篇
  2011年   32篇
  2010年   7篇
  2009年   2篇
  2008年   19篇
  2007年   19篇
  2006年   17篇
  2005年   10篇
  2004年   18篇
  2003年   16篇
  2002年   15篇
  2001年   6篇
  2000年   7篇
  1999年   6篇
  1997年   1篇
  1996年   2篇
  1992年   5篇
  1989年   1篇
  1988年   3篇
  1986年   1篇
  1985年   1篇
  1984年   2篇
  1983年   2篇
  1982年   1篇
  1980年   1篇
  1979年   1篇
  1978年   2篇
  1977年   1篇
  1975年   2篇
  1974年   1篇
  1973年   1篇
  1971年   1篇
  1970年   8篇
  1969年   5篇
  1968年   1篇
排序方式: 共有257条查询结果,搜索用时 15 毫秒
81.
The plant Arabidopsis thaliana occurs naturally in many different habitats throughout Eurasia. As a foundation for identifying genetic variation contributing to adaptation to diverse environments, a 1001 Genomes Project to sequence geographically diverse A. thaliana strains has been initiated. Here we present the first phase of this project, based on population-scale sequencing of 80 strains drawn from eight regions throughout the species' native range. We describe the majority of common small-scale polymorphisms as well as many larger insertions and deletions in the A. thaliana pan-genome, their effects on gene function, and the patterns of local and global linkage among these variants. The action of processes other than spontaneous mutation is identified by comparing the spectrum of mutations that have accumulated since A. thaliana diverged from its closest relative 10 million years ago with the spectrum observed in the laboratory. Recent species-wide selective sweeps are rare, and potentially deleterious mutations are more common in marginal populations.  相似文献   
82.
Analysis of the coding genome of diffuse large B-cell lymphoma   总被引:1,自引:0,他引:1  
Diffuse large B-cell lymphoma (DLBCL) is the most common form of human lymphoma. Although a number of structural alterations have been associated with the pathogenesis of this malignancy, the full spectrum of genetic lesions that are present in the DLBCL genome, and therefore the identity of dysregulated cellular pathways, remains unknown. By combining next-generation sequencing and copy number analysis, we show that the DLBCL coding genome contains, on average, more than 30 clonally represented gene alterations per case. This analysis also revealed mutations in genes not previously implicated in DLBCL pathogenesis, including those regulating chromatin methylation (MLL2; 24% of samples) and immune recognition by T cells. These results provide initial data on the complexity of the DLBCL coding genome and identify novel dysregulated pathways underlying its pathogenesis.  相似文献   
83.
84.
Multiple organs cooperate to regulate appetite, metabolism, and glucose and fatty acid homeostasis. Here, we identified and characterized lymphatic vasculature dysfunction as a cause of adult-onset obesity. We found that functional inactivation of a single allele of the homeobox gene Prox1 led to adult-onset obesity due to abnormal lymph leakage from mispatterned and ruptured lymphatic vessels. Prox1 heterozygous mice are a new model for adult-onset obesity and lymphatic vascular disease.  相似文献   
85.
86.
Perillartine and some derivatives: clarification of structures   总被引:1,自引:0,他引:1  
  相似文献   
87.
Emissivity of human skin in the waveband between 2micra and 6micra   总被引:1,自引:0,他引:1  
D J Watmough  R Oliver 《Nature》1968,219(5154):622-624
  相似文献   
88.
Control of cell surface topography   总被引:14,自引:0,他引:14  
R D Berlin  J M Oliver  T E Ukena  H H Yin 《Nature》1974,247(5435):45-46
  相似文献   
89.
90.
The research described in this paper is undertaken under the banner of the smart city, a concept that captures the way urban spaces are re-made by the incursion of new technology. Much of smart is centred on converting everyday activities into data, and using this data to generate knowledge mediated by technology. Ordinary citizens, those that may have their lives impacted by the technology, usually are not properly involved in the ‘smartification’ process. Their perceptions, concerns and expectations should inform the conception and development of smart technologies at the same extent. How to engage general public with smart cities research is the central challenge for the Making Metrics Meaningful (MMM) project. Applying a rapid participatory method, ‘Imagine’ over a five-month period (March – July) the research sought to gain insights from the general public into novel forms of information system innovation. This brief paper describes the nature of the accelerated research undertaken and explores some of the themes which emerged in the analysis. Generic themes, beyond the remit of an explicit transport focus, are developed and pointers towards further research directions are discussed. Participatory methods, including engaging with self-selected transport users actively through both picture creation and programmatically specific musical ‘signatures’ as well as group discussion, were found to be effective in eliciting users’ own concerns, needs and ideas for novel information systems.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号