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   248329篇
  免费   12562篇
  国内免费   427篇
耳鼻咽喉   3317篇
儿科学   7730篇
妇产科学   5033篇
基础医学   35612篇
口腔科学   5615篇
临床医学   19882篇
内科学   54528篇
皮肤病学   6955篇
神经病学   22311篇
特种医学   7676篇
外国民族医学   103篇
外科学   31403篇
综合类   1185篇
一般理论   63篇
预防医学   22350篇
眼科学   4824篇
药学   17339篇
中国医学   722篇
肿瘤学   14670篇
  2023年   1290篇
  2022年   961篇
  2021年   3655篇
  2020年   2190篇
  2019年   4052篇
  2018年   7702篇
  2017年   5071篇
  2016年   5149篇
  2015年   5699篇
  2014年   6037篇
  2013年   9709篇
  2012年   16700篇
  2011年   16697篇
  2010年   8372篇
  2009年   6319篇
  2008年   14291篇
  2007年   15340篇
  2006年   14187篇
  2005年   14019篇
  2004年   13176篇
  2003年   12065篇
  2002年   11443篇
  2001年   6684篇
  2000年   6729篇
  1999年   6036篇
  1998年   1065篇
  1997年   871篇
  1996年   803篇
  1995年   756篇
  1992年   3440篇
  1991年   3147篇
  1990年   2967篇
  1989年   2722篇
  1988年   2561篇
  1987年   2396篇
  1986年   2287篇
  1985年   2090篇
  1984年   1531篇
  1983年   1323篇
  1979年   1338篇
  1978年   942篇
  1977年   885篇
  1975年   913篇
  1974年   1099篇
  1973年   1095篇
  1972年   1044篇
  1971年   1018篇
  1970年   937篇
  1969年   985篇
  1968年   876篇
排序方式: 共有10000条查询结果,搜索用时 46 毫秒
31.
32.
33.

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   
34.
35.
36.
37.
38.
39.
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   
40.
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