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   31984篇
  免费   1584篇
  国内免费   139篇
耳鼻咽喉   347篇
儿科学   787篇
妇产科学   433篇
基础医学   4192篇
口腔科学   864篇
临床医学   2118篇
内科学   8372篇
皮肤病学   578篇
神经病学   2364篇
特种医学   999篇
外科学   5489篇
综合类   156篇
一般理论   4篇
预防医学   1029篇
眼科学   524篇
药学   2340篇
中国医学   126篇
肿瘤学   2985篇
  2023年   170篇
  2022年   305篇
  2021年   558篇
  2020年   271篇
  2019年   418篇
  2018年   511篇
  2017年   451篇
  2016年   498篇
  2015年   491篇
  2014年   660篇
  2013年   845篇
  2012年   1323篇
  2011年   1423篇
  2010年   847篇
  2009年   743篇
  2008年   1381篇
  2007年   1540篇
  2006年   1486篇
  2005年   1617篇
  2004年   1510篇
  2003年   1489篇
  2002年   1413篇
  2001年   1182篇
  2000年   1268篇
  1999年   1101篇
  1998年   424篇
  1997年   301篇
  1996年   311篇
  1995年   283篇
  1994年   246篇
  1993年   249篇
  1992年   771篇
  1991年   710篇
  1990年   672篇
  1989年   735篇
  1988年   644篇
  1987年   605篇
  1986年   548篇
  1985年   521篇
  1984年   340篇
  1983年   285篇
  1979年   267篇
  1978年   189篇
  1977年   159篇
  1974年   157篇
  1973年   166篇
  1972年   168篇
  1971年   157篇
  1970年   155篇
  1969年   144篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
1.
International Journal of Clinical Oncology - The practice of cancer diagnosis disclosure to children has been changed with the times. The regulations of clinical trials in the 2000s might change...  相似文献   
2.
3.
4.
5.
6.
7.
8.
9.
Objective: Induction chemoradiotherapy followed by anatomical resection is a current therapeutic strategy for non-small-cell lung cancer with mediastinal node involvement. Dense peritracheal fibrosis and sclerosis after chemoradiotherapy cause difficult mediastinal node dissection. We evaluated a novel technique to make the mediastinal node dissection easier after induction therapy. Methods: At the end of mediastinoscopic node biopsy for staging of lung cancer, cotton-type collagen was inserted anterior and lateral to the trachea in patients with pathologically confirmed mediastinal node involve-ment (n=45). The induction therapy consisted of concurrent use of platinum-based chemotherapy and hyperfractionated radiotherapy. After the chemoradiotherapy all patients underwent a pulmonary resection with complete mediastinal node dissection 7–12 weeks after the collagen insertion. Surgical findings of the mediastinum and the time for node dissection were compared with those without collagen insertion at mediastinoscopy after chemoradiotherapy (n=5). Results: All five patients without collagen insertion showed sclerotic and fibrotic change of mediastinal nodes with severe adhesion to the trachea. In 42 of 45 patients with collagen insertion (93.3%) the collagen remained unabsorbed and separated the mediastinal nodes from the trachea. Mediastinal node dissection was easily accomplished by removing mediastinal tissues lateral and anterior to the collagen. The rate of mediastinal node separation was significantly higher with collagen insertion than without (p< 0.0001). The times for node dissection in patients with and without collagen insertion showed no significant difference. Conclusion: Cotton-type collagen insertion at staging mediastinoscopy for lung cancer separates the mediastinal nodes from the trachea and makes the node dissection easier after induction chemoradiotherapy.  相似文献   
10.
Anthocyanins, which are responsible for a variety of bright colors (including red, blue, and purple) in fruits, vegetables, and flowers, are consumed as dietary polyphenols. Anthocyanin-containing fruits are thought to decrease coronary heart disease and are used in anti-diabetic preparations. Diabetes is associated with a variety of cardiovascular complications that may be mediated by endothelial dysfunction, and so this study was designed mainly to characterize the influence of a synthesized anthocyanidin derivative (HK-008) over acetylcholine (ACh)-induced relaxation in mesenteric arterial beds isolated from rats. In a glucose-tolerance test in intact rats, HK-008 (30 mg/kg) reduced the glucose level as effectively as the same dose of glibenclamide. The aortic relaxation induced by pinacidil (an ATP-sensitive potassium channel opener) was greatly inhibited by glibenclamide (10 microM), and also significantly inhibited by HK-008 (10 microM). Interestingly, the ACh-induced relaxation in the perfused, preconstricted mesenteric arterial bed was significantly enhanced by HK-008 (10 microM), and this enhancement was significantly attenuated by indomethacin (10 microM). The ACh-induced mesenteric relaxation was impaired by an increase in oxidative stress, viz. superoxide-generating treatment [xanthine oxidase (XO; 0.1 U/ml) plus hypoxanthine (HX; 10 microM)]. However, this impairment was strongly suppressed by HK-008 (10 microM). These results suggest that HK-008 increases endothelium-induced relaxation by suppressing oxidative stress or modulating prostanoids signaling. This compound may therefore be useful against certain cardiovascular disorders.  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