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   1243480篇
  免费   78194篇
  国内免费   1750篇
耳鼻咽喉   17351篇
儿科学   39574篇
妇产科学   32464篇
基础医学   177024篇
口腔科学   35237篇
临床医学   105143篇
内科学   240816篇
皮肤病学   28957篇
神经病学   95321篇
特种医学   47229篇
外国民族医学   202篇
外科学   183615篇
综合类   22510篇
现状与发展   1篇
一般理论   293篇
预防医学   93445篇
眼科学   28989篇
药学   98659篇
  7篇
中国医学   3477篇
肿瘤学   73110篇
  2021年   10275篇
  2019年   10759篇
  2018年   16535篇
  2017年   12196篇
  2016年   13459篇
  2015年   15000篇
  2014年   19310篇
  2013年   28416篇
  2012年   41085篇
  2011年   43445篇
  2010年   24498篇
  2009年   21940篇
  2008年   39022篇
  2007年   41826篇
  2006年   41977篇
  2005年   40034篇
  2004年   38055篇
  2003年   36402篇
  2002年   34849篇
  2001年   64728篇
  2000年   66766篇
  1999年   54975篇
  1998年   13217篇
  1997年   11523篇
  1996年   11523篇
  1995年   10752篇
  1994年   9707篇
  1993年   9163篇
  1992年   39939篇
  1991年   38171篇
  1990年   37575篇
  1989年   35890篇
  1988年   32391篇
  1987年   31365篇
  1986年   29642篇
  1985年   27804篇
  1984年   20158篇
  1983年   16962篇
  1982年   9291篇
  1979年   18135篇
  1978年   12173篇
  1977年   10955篇
  1976年   9513篇
  1975年   10900篇
  1974年   12687篇
  1973年   12366篇
  1972年   11812篇
  1971年   11095篇
  1970年   10178篇
  1969年   9954篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
31.
32.

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   
33.
34.
35.
36.
37.
38.
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   
39.
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