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   254432篇
  免费   11090篇
  国内免费   655篇
耳鼻咽喉   3552篇
儿科学   7119篇
妇产科学   5878篇
基础医学   35554篇
口腔科学   8718篇
临床医学   15420篇
内科学   58481篇
皮肤病学   6996篇
神经病学   21171篇
特种医学   6371篇
外国民族医学   2篇
外科学   30437篇
综合类   1172篇
一般理论   59篇
预防医学   27901篇
眼科学   6181篇
药学   19178篇
  1篇
中国医学   1031篇
肿瘤学   10955篇
  2023年   1369篇
  2022年   1221篇
  2021年   4312篇
  2020年   2392篇
  2019年   4736篇
  2018年   7952篇
  2017年   4990篇
  2016年   4983篇
  2015年   5555篇
  2014年   6496篇
  2013年   9720篇
  2012年   16492篇
  2011年   17431篇
  2010年   8849篇
  2009年   6548篇
  2008年   14457篇
  2007年   15357篇
  2006年   14483篇
  2005年   14201篇
  2004年   13012篇
  2003年   12212篇
  2002年   11521篇
  2001年   7226篇
  2000年   8096篇
  1999年   6240篇
  1998年   1204篇
  1992年   3067篇
  1991年   2675篇
  1990年   2570篇
  1989年   2174篇
  1988年   2070篇
  1987年   1946篇
  1986年   1959篇
  1985年   1808篇
  1984年   1336篇
  1983年   1141篇
  1979年   1426篇
  1978年   944篇
  1977年   913篇
  1976年   889篇
  1975年   1032篇
  1974年   1315篇
  1973年   1387篇
  1972年   1296篇
  1971年   1274篇
  1970年   1173篇
  1969年   1238篇
  1968年   1274篇
  1967年   1132篇
  1966年   999篇
排序方式: 共有10000条查询结果,搜索用时 234 毫秒
31.
32.
33.
34.

Background

Since recent reports have shown that (-)-Epigallocatechin-3-gallate (EGCG) could be used for treating proliferative and inflammatory disorders, we explored its use for the management of corneal chemical burns.

Materials and methods

Initially, EGCG was assayed on the rabbit corneal epithelial cell line RCE1(5T5) to establish the best testing conditions, and to avoid unwanted outcomes in the experimental animals. Then, we studied its effects on cell proliferation, cell cycle progression and cell differentiation. Afterwards, we instilled EGCG in experimental grade II corneal alkali burns in mice, three times a day up to 21 days, and evaluated by slit lamp examination and histological sections of corneal epithelial, corneal endothelial and stromal edema, as well as the presence of inflammatory cells and neovascularization.

Results

EGCG reduced cell growth and led to a decline in the proportion of proliferative cells in a concentration dependent manner. At 10 μM, EGCG promoted cell differentiation, an effect not related with apoptosis or cytotoxicity. When 10 μM EGCG was instilled in corneal alkali burns in mice three times a day up to 21 days, EGCG significantly reduced corneal opacity and neovascularization. The improved clinical appearance of the cornea was associated to a controlled epithelial growth; epithelial morphology was similar to that observed in normal epithelium and contrasted with the hyperproliferative, desquamating epithelium observed in control burn wounds. EGCG reduced corneal, stromal and endothelial edema, and wound inflammation.

Conclusion

This work constitutes the first evidence for the use of EGCG in the acute phase of a corneal alkali burn, representing a possible novel alternative to improve patient outcomes as an add-on therapy.  相似文献   
35.
36.
37.
38.
39.
40.
Pulmonary hypertension of the newborn (PHN) constitutes a critical condition with severe cardiovascular and neurological consequences. One of its main causes is hypoxia during gestation, and thus, it is a public health concern in populations living above 2500 m. Although some mechanisms are recognized, the pathophysiological facts that lead to PHN are not fully understood, which explains the lack of an effective treatment. Oxidative stress is one of the proposed mechanisms inducing pulmonary vascular dysfunction and PHN. Therefore, we assessed whether melatonin, a potent antioxidant, improves pulmonary vascular function. Twelve newborn sheep were gestated, born, and raised at 3600 meters. At 3 days old, lambs were catheterized and daily cardiovascular measurements were recorded. Lambs were divided into two groups, one received daily vehicle as control and another received daily melatonin (1 mg/kg/d), for 8 days. At 11 days old, lung tissue and small pulmonary arteries (SPA) were collected. Melatonin decreased pulmonary pressure and resistance for the first 3 days of treatment. Further, melatonin significantly improved the vasodilator function of SPA, enhancing the endothelial‐ and muscular‐dependent pathways. This was associated with an enhanced nitric oxide‐dependent and nitric oxide independent vasodilator components and with increased nitric oxide bioavailability in lung tissue. Further, melatonin reduced the pulmonary oxidative stress markers and increased enzymatic and nonenzymatic antioxidant capacity. Finally, these effects were associated with an increase of lumen diameter and a mild decrease in the wall of the pulmonary arteries. These outcomes support the use of melatonin as an adjuvant in the treatment for PHN.  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