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   3640篇
  免费   283篇
  国内免费   19篇
耳鼻咽喉   14篇
儿科学   68篇
妇产科学   133篇
基础医学   608篇
口腔科学   35篇
临床医学   349篇
内科学   685篇
皮肤病学   78篇
神经病学   493篇
特种医学   126篇
外科学   338篇
综合类   29篇
一般理论   5篇
预防医学   332篇
眼科学   55篇
药学   229篇
中国医学   5篇
肿瘤学   360篇
  2024年   2篇
  2023年   35篇
  2022年   81篇
  2021年   129篇
  2020年   92篇
  2019年   89篇
  2018年   107篇
  2017年   103篇
  2016年   140篇
  2015年   148篇
  2014年   190篇
  2013年   223篇
  2012年   350篇
  2011年   375篇
  2010年   172篇
  2009年   164篇
  2008年   264篇
  2007年   241篇
  2006年   231篇
  2005年   229篇
  2004年   180篇
  2003年   173篇
  2002年   137篇
  2001年   14篇
  2000年   7篇
  1999年   16篇
  1998年   15篇
  1997年   12篇
  1996年   6篇
  1995年   1篇
  1993年   4篇
  1992年   1篇
  1991年   1篇
  1990年   2篇
  1989年   2篇
  1988年   1篇
  1985年   1篇
  1980年   2篇
  1979年   2篇
排序方式: 共有3942条查询结果,搜索用时 15 毫秒
81.
82.
Dysregulation of apoptosis caused by an imbalance of pro‐ and anti‐apoptotic protein expression can lead to cancer, neurodegenerative, and autoimmune diseases. Cellular‐FLIP (c‐FLIP) proteins inhibit apoptosis directly at the death‐inducing signaling complex of death receptors, such as CD95, and have been linked to apoptosis regulation during immune responses. While the isoforms c‐FLIPL and c‐FLIPS are well characterized, the function of c‐FLIPR remains poorly understood. Here, we demonstrate the induction of endogenous murine c‐FLIPR in activated lymphocytes for the first time. To analyze c‐FLIPR function in vivo, we generated transgenic mice expressing murine c‐FLIPR specifically in hematopoietic cells. As expected, lymphocytes from c‐FLIPR transgenic mice were protected against CD95‐induced apoptosis in vitro. In the steady state, transgenic mice had normal cell numbers and unaltered frequencies of B cells and T‐cell subsets in lymphoid organs. However, when challenged with Listeria monocytogenes, c‐FLIPR transgenic mice showed less liver necrosis and better bacterial clearance compared with infected wild‐type mice. We conclude that c‐FLIPR expression in hematopoietic cells supports an efficient immune response against bacterial infections.  相似文献   
83.
Prostate growth seems to be influenced by paracrine factors like endothelin-1 (ET-1), originating from the microvascular endothelium. Recently, we reported on the first isolation and primary culture of microvascular endothelial cells (HPEC) derived from tissue of human benign prostatic hyperplasia (BPH). Therefore, direct investigation of growth factor secretion by HPEC is now possible.

BPH tissue was cut into small cubes and gently squeezed after incubation with dispase. HPEC were cultured from the resulting cell suspension after a stepwise selection by use of superparamagnetic beads coated with antibodies against endothelial specific antigens. HPEC were characterized by flow cytometry. After the incubation of HPEC either with vascular endothelial growth factor (VEGF), tumor necrosis factor α (TNF-α), or adenosine triphosphate (ATP), the secretion of ET-1 was measured by ELISA.

HPEC showed a typical endothelial morphology. They were positive for von Willebrand factor and CD31. The ET-1 secretion of HPEC was inhibited by VEGF, but was unaffected by TNF-α or ATP. Furthermore, histochemistry revealed that in vivo microvascular endothelial cells were negative for ET-1. Because of the suppression by the widespread VEGF, it is unlikely that ET-1 from the microvascular endothelium acts as a growth factor in human BPH.  相似文献   
84.
85.
86.
87.
88.
We report two cases highlighting the diversity of vagal nerve stimulation (VNS)‐related effects on voice and breathing in patients with refractory epilepsy. The patients had both implantation and stimulation‐related side effects, which lasted for several months, impacting on their quality of life. The adverse effects appear to be due to recurrent laryngeal nerve paralysis‐related vocal cord hypofunction and stimulation‐related vocal fold spasms, however, their inter‐relationship is complex. In one of the patients, we were able to utilize the novel programming capabilities of the VNS device to reduce the laryngeal side effects without compromising therapeutic efficacy. [Published with video sequences].  相似文献   
89.
90.
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