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   733篇
  免费   56篇
  国内免费   2篇
耳鼻咽喉   2篇
儿科学   5篇
妇产科学   13篇
基础医学   99篇
口腔科学   13篇
临床医学   52篇
内科学   132篇
皮肤病学   8篇
神经病学   108篇
特种医学   75篇
外科学   76篇
综合类   6篇
预防医学   18篇
眼科学   132篇
药学   29篇
肿瘤学   23篇
  2023年   9篇
  2022年   7篇
  2021年   15篇
  2020年   5篇
  2019年   14篇
  2018年   10篇
  2017年   16篇
  2016年   26篇
  2015年   15篇
  2014年   15篇
  2013年   32篇
  2012年   57篇
  2011年   66篇
  2010年   26篇
  2009年   26篇
  2008年   38篇
  2007年   44篇
  2006年   40篇
  2005年   45篇
  2004年   40篇
  2003年   44篇
  2002年   38篇
  2001年   22篇
  2000年   12篇
  1999年   7篇
  1998年   7篇
  1997年   13篇
  1996年   2篇
  1995年   6篇
  1994年   5篇
  1993年   4篇
  1992年   5篇
  1991年   7篇
  1990年   5篇
  1989年   4篇
  1988年   6篇
  1987年   2篇
  1986年   3篇
  1984年   5篇
  1983年   4篇
  1982年   3篇
  1981年   3篇
  1980年   4篇
  1979年   5篇
  1978年   2篇
  1976年   2篇
  1974年   2篇
  1972年   2篇
  1903年   7篇
  1886年   1篇
排序方式: 共有791条查询结果,搜索用时 15 毫秒
1.
The impact of primary hand osteoarthritis (HOA) on bone mass, microstructure, and biomechanics in the affected skeletal regions is largely unknown. HOA patients and healthy controls (HCs) underwent high-resolution peripheral quantitative computed tomography (HR-pQCT). We measured total, trabecular, and cortical volumetric bone mineral densities (vBMDs), microstructural attributes, and performed micro–finite element analysis for bone strength. Failure load and scaled multivariate outcome matrices from distal radius and second metacarpal (MCP2) head measurements were analyzed using multiple linear regression adjusting for age, sex, and functional status and reported as adjusted Z-score differences for total and direct effects. A total of 105 subjects were included (76 HC: 46 women, 30 men; 29 HOA: 23 women, six men). After adjustment, HOA was associated with significant changes in the multivariate outcome matrix from the MCP2 head (p < .001) (explained by an increase in cortical vBMD (Δz = 1.07, p = .02) and reduction in the trabecular vBMD (Δz = −0.07, p = .09). Distal radius analysis did not show an overall effect of HOA; however, there was a gender-study group interaction (p = .044) explained by reduced trabecular vBMD in males (Δz = −1.23, p = .02). HOA was associated with lower failure load (−514 N; 95%CI, −1018 to −9; p = 0.05) apparent in males after adjustment for functional status. HOA is associated with reduced trabecular and increased cortical vBMD in the MCP2 head and a reduction in radial trabecular vBMD and bone strength in males. Further investigations of gender-specific changes of bone architecture in HOA are warranted. © 2020 The Authors. Journal of Bone and Mineral Research published by American Society for Bone and Mineral Research.  相似文献   
2.
3.
The goal of the present study was to test the impact of administration time of the angiotensin II type 1-receptor blocker candesartan on cerebral blood flow (CBF), infarct size, and neuroscore in transient cerebral ischemia. Therefore, 1-hour middle cerebral artery occlusion (MCAO) was followed by reperfusion. Rats received 0.5-mg/kg candesartan intravenously 2 hours before MCAO (pretreatment), 24 hours after MCAO, every 24 hours after MCAO, or 2 hours before and every 24 hours after MCAO. Infarct size (mm3) and a neuroscore at day 7 were compared with controls. CBF was quantified by radiolabeled microspheres and laser-Doppler flowmetry. Compared with controls (95 +/- 8), infarct size in candesartan-treated groups was smaller (59 +/- 5, 68 +/- 10, 28 +/- 3, and 15 +/- 3, respectively; P<0.05). Although there was no difference in neuroscore between pretreatment and controls (1.55 +/- 0.18, 1.80 +/- 0.13), other treatment regimens resulted in improved neuroscores (1.33 +/- 0.16, 1.11 +/- 0.11, 0.73 +/- 0.15; P<0.05). CBF in pretreated animals at 0.5 hours after MCAO was significantly higher than in controls (0.58 +/- 0.09 mL x g(-1) x min(-1) and 44% +/- 7% of baseline compared with 0.49 +/- 0.06 mL x g(-1) x min(-1) and 37% +/- 6%, microspheres and laser-Doppler flowmetry; P<0.05). Thus, candesartan reduces infarct size even if administered only during reperfusion. Apart from pretreatment, other treatment regimens result in significantly improved neuroscores. In the acute phase of cerebral ischemia, candesartan increases CBF.  相似文献   
4.
5.
实验性单纯疱疹性角膜炎的组织病理学研究   总被引:1,自引:0,他引:1  
目的:动态观察1型单纯疱疹病毒(HSV-1)感染角膜后的组织病理改变。方法:BALB/c小鼠眼角膜接种HSV-1(KOS株)以诱发单纯疱疹性角膜炎(HSK)。分别收集正常眼球及感染后第2、7、14天的感染眼球,组织学观察结膜及角膜的病理过程。结果:感染后第2天,中性粒细胞、淋巴细胞及其他单核细胞浸润结膜并在第7-14天间快速向中央角膜扩散。结论:在HSK发展中,中性粒细胞浸润导致进行性的组织破坏。  相似文献   
6.
The existence of a new Apa LI restriction fragment length polymorphism in the third intron of the low density lipoprotein (LDL) receptor gene was described. As a gene probe we used a newly constructed derivative of pLDLR 3 which did not contain the highly repetitive Alu-sequences in exon 18. This new gene probe detected all exon sequences containing restriction fragments, and enabled us to demonstrate all described polymorphisms, which might be useful for genetic linkage studies. Based on analysis of 72 unrelated normo- and hypercholesterolaemic persons, the frequency of the allele A2, which showed the additional cutting site, was determined to be 0.05. With the simplified gene probe, pLDLR delta, we also studied other polymorphisms. A clear linkage disequilibrium between the Pvu II and Msp I polymorphisms was detected. This, and the previously described linkage disequilibrium of the two Msp I polymorphisms, demonstrate that the LDL receptor gene is apparently less heterogeneous than expected from the number of described polymorphisms.  相似文献   
7.
8.
9.
10.
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