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   8686篇
  免费   343篇
  国内免费   50篇
耳鼻咽喉   69篇
儿科学   177篇
妇产科学   186篇
基础医学   1172篇
口腔科学   244篇
临床医学   441篇
内科学   2032篇
皮肤病学   178篇
神经病学   635篇
特种医学   412篇
外科学   1601篇
综合类   21篇
一般理论   1篇
预防医学   205篇
眼科学   89篇
药学   549篇
中国医学   31篇
肿瘤学   1036篇
  2023年   39篇
  2022年   61篇
  2021年   135篇
  2020年   59篇
  2019年   77篇
  2018年   114篇
  2017年   90篇
  2016年   142篇
  2015年   158篇
  2014年   206篇
  2013年   245篇
  2012年   424篇
  2011年   461篇
  2010年   255篇
  2009年   231篇
  2008年   455篇
  2007年   526篇
  2006年   503篇
  2005年   614篇
  2004年   601篇
  2003年   598篇
  2002年   585篇
  2001年   127篇
  2000年   104篇
  1999年   131篇
  1998年   174篇
  1997年   153篇
  1996年   135篇
  1995年   127篇
  1994年   132篇
  1993年   104篇
  1992年   126篇
  1991年   111篇
  1990年   112篇
  1989年   91篇
  1988年   98篇
  1987年   86篇
  1986年   64篇
  1985年   77篇
  1984年   61篇
  1983年   43篇
  1982年   42篇
  1981年   46篇
  1980年   43篇
  1979年   40篇
  1978年   35篇
  1977年   24篇
  1976年   34篇
  1975年   18篇
  1971年   18篇
排序方式: 共有9079条查询结果,搜索用时 15 毫秒
1.
2.
The effect of electric charge on the hepatic disposition of macromolecules was studied in the rat. Charged derivatives of dextran (T-70) and bovine serum albumin (BSA), mitomycin C–dextran conjugates (MMC-D), and lactosaminated BSA (Lac-BSA) were employed as model macromolecules. After intravenous injection, cationic macromolecules were rapidly eliminated from plasma because of their extensive hepatic uptake, while anionic and neutral macromolecules were slowly eliminated. Cationic macromolecules were recovered from parenchymal and nonparenchymal hepatic cells at a cellular uptake (per unit cell number) ratio of 1.4–3.2, while that of Lac-BSA was 14. During liver perfusion using a single-pass constant infusion mode, cationic macromolecules were continuously extracted by the liver, with extraction ratios at steady-state (E ss) ranging between 0.03 and 0.54, whereas anionic and neutral macromolecules were almost completely recovered in the outflow at steady state. The E ss for cationized BSA (Cat-BSA) and cationic MMC-Dcat were concentration dependent and decreased at low temperatures and in the presence of colchicine and cytochalasin B. The possible participation of the internalization process in the uptake of cationic macromolecules by hepatocytes was suggested.  相似文献   
3.
4.
5.
The leukocyte-endothelium interaction is known to contribute to reperfusion injury, which is considered to participate in the pathophysiology of pressure ulcers, and integrin alphaV beta3 (alphavbeta3) has been shown to mediate the processes of cellular adhesion in various types of cells. This study aims to clarify leukocyte behavior in our original microcirculatory pressure-induced reperfusion model, which can visualize the microcirculation in vivo. We also estimated the effect of alphavbeta3 integrin inhibition on the reduction of the leukocyte-endothelium interaction. Mice with dorsal skinfold chambers were divided into three groups: the baseline group (n=6), in which animals received no compression; the compression-reperfusion group (n=6), in which animals underwent 2-hour compression of the dorsal skin, followed by release, and the inhibitor-treated group (n=7), in which an alphavbeta3 inhibitor, CP4715, was administered in addition to the compression-release procedure. Staining with rhodamine 6G quantitatively visualized leukocyte behavior under the intravital fluorescent microscope. Compression-reperfusion induced a significant increase in rolling, sticking, and extravasation of the leukocytes. Treatment with the inhibitor strikingly reduced leukocyte sticking and extravasation. The present experiment has provided evidence that alphavbeta3 inhibition reduces leukocyte-endothelium interaction in our original pressure-induced reperfusion model.  相似文献   
6.
7.
A 78-year-old woman with diagnosis of acute myocardial infarction (AMI) in the anteroseptal area fell into cardiogenic shock suddenly just before starting percutaneous coronary intervention (PCI). Echocardiography showed left ventricular free wall rupture, then an emergent operation was performed by sutureless patch repair using collagen fleece with fibrinogen-based impregnation. Eight days later from the initial operation, the onset of ventricular septal perforation (VSP) was recognized. Fifteen days after, the infarct exclusion technique with endocardial patch was performed. She has been doing well 4 months after the operation without residual shunt. To our best knowledge, this is the first surgical case report that free wall rupture of left ventricle and VSP which are serious complications after myocardial infarction happened in succession.  相似文献   
8.
9.
A rare case of urinary bladder carcinoma with granulocyte colony stimulating factor (G-CSF) production was reported. In an 83-year-old female, marked neutrophilia in the peripheral blood decreased from 132,500/mm3 to 3,300/mm3 after tumour resection. The tumour was a transitional cell carcinoma. The serum G-CSF level reduced from 238 pg/ml pre-operatively to normal (60 pg/ml) after the operation. Immunohistochemical investigation of the resected tumour with monoclonal antibody specific for G-CSF revealed positive staining in the carcinoma cells, confirming G-CSF secretion.  相似文献   
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