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   429篇
  免费   51篇
  2023年   2篇
  2021年   6篇
  2020年   3篇
  2019年   2篇
  2018年   5篇
  2017年   8篇
  2016年   9篇
  2015年   18篇
  2014年   14篇
  2013年   23篇
  2012年   33篇
  2011年   29篇
  2010年   26篇
  2009年   20篇
  2008年   19篇
  2007年   20篇
  2006年   18篇
  2005年   15篇
  2004年   11篇
  2003年   14篇
  2002年   16篇
  2001年   6篇
  2000年   14篇
  1999年   16篇
  1998年   8篇
  1997年   10篇
  1995年   5篇
  1994年   4篇
  1993年   3篇
  1992年   12篇
  1991年   6篇
  1990年   8篇
  1989年   7篇
  1988年   10篇
  1987年   6篇
  1985年   4篇
  1984年   6篇
  1981年   2篇
  1979年   5篇
  1978年   4篇
  1977年   2篇
  1974年   2篇
  1973年   4篇
  1967年   1篇
  1966年   2篇
  1964年   2篇
  1942年   2篇
  1941年   3篇
  1940年   4篇
  1915年   2篇
排序方式: 共有480条查询结果,搜索用时 17 毫秒
1.
2.
3.
4.
5.
In patients with unexplained hypertension, especially in combination with a cardiac murmur, the presence of an aortic coarctation should always be ruled out given the high morbidity and mortality. However, particularly patients with an isolated coarctation often remain asymptomatic for years and the defect may be unnoticed even until the fifth or sixth decade of life. In the present article, we describe two patients with late detected coarctation to illustrate the clinical consequences, diagnostic clues for earlier detection and current therapeutic options to achieve optimal treatment. The key sign of an aortic coarctation, a difference in arterial blood pressure measured between the upper and lower extremities, should always be examined, followed by echocardiography. We conclude that even in case of a late detected severe coarctation, surgical or percutaneous repair has proven to be feasible and substantially effective, improving quality of life and lowering the risk of further hypertension-associated problems.  相似文献   
6.
Extremophiles - Genotypic and morphological diversity of cyanobacteria in the Rupite hot spring (Bulgaria) was investigated by means of optical microscopy, cultivation, single-cell PCR, and 16S...  相似文献   
7.
8.

Background  

A recent study on expression and function of the ortholog of the Drosophila collier (col) gene in various arthropods including insects, crustaceans and chelicerates suggested a de novo function of col in the development of the appendage-less intercalary segment of insects. However, this assumption was made on the background of the now widely-accepted Pancrustacea hypothesis that hexapods represent an in-group of the crustaceans. It was therefore assumed that the expression of col in myriapods would reflect the ancestral state like in crustaceans and chelicerates, i.e. absence from the premandibular/intercalary segment and hence no function in its formation.  相似文献   
9.
10.
Membrane proteins serve as cellular gatekeepers, regulators, and sensors. Prior studies have explored the functional breadth and evolution of proteins and families of particular interest, such as the diversity of transport-associated membrane protein families in prokaryotes and eukaryotes, the composition of integral membrane proteins, and family classification of all human G-protein coupled receptors. However, a comprehensive analysis of the content and evolutionary associations between membrane proteins and families in a diverse set of genomes is lacking. Here, a membrane protein annotation pipeline was developed to define the integral membrane genome and associations between 21,379 proteins from 34 genomes; most, but not all of these proteins belong to 598 defined families. The pipeline was used to provide target input for a structural genomics project that successfully cloned, expressed, and purified 61 of our first 96 selected targets in yeast. Furthermore, the methodology was applied (1) to explore the evolutionary history of the substrate-binding transmembrane domains of the human ABC transporter superfamily, (2) to identify the multidrug resistance-associated membrane proteins in whole genomes, and (3) to identify putative new membrane protein families.  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