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   279952篇
  免费   13554篇
  国内免费   489篇
耳鼻咽喉   3674篇
儿科学   8268篇
妇产科学   5739篇
基础医学   39750篇
口腔科学   7314篇
临床医学   21950篇
内科学   62547篇
皮肤病学   7354篇
神经病学   25141篇
特种医学   8154篇
外国民族医学   101篇
外科学   35361篇
综合类   1185篇
一般理论   82篇
预防医学   25280篇
眼科学   5500篇
药学   19501篇
中国医学   856篇
肿瘤学   16238篇
  2023年   1521篇
  2022年   977篇
  2021年   4140篇
  2020年   2466篇
  2019年   4602篇
  2018年   8790篇
  2017年   5701篇
  2016年   5775篇
  2015年   6833篇
  2014年   7068篇
  2013年   11297篇
  2012年   19801篇
  2011年   19704篇
  2010年   9716篇
  2009年   7225篇
  2008年   16998篇
  2007年   18069篇
  2006年   17091篇
  2005年   16768篇
  2004年   15607篇
  2003年   14253篇
  2002年   13524篇
  2001年   7357篇
  2000年   7898篇
  1999年   6324篇
  1998年   1055篇
  1997年   858篇
  1996年   826篇
  1995年   757篇
  1992年   3297篇
  1991年   2950篇
  1990年   2790篇
  1989年   2559篇
  1988年   2416篇
  1987年   2239篇
  1986年   2139篇
  1985年   1939篇
  1984年   1473篇
  1983年   1236篇
  1979年   1237篇
  1978年   879篇
  1977年   824篇
  1975年   821篇
  1974年   1014篇
  1973年   1020篇
  1972年   940篇
  1971年   934篇
  1970年   871篇
  1969年   917篇
  1968年   792篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
3.

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   
4.
5.
6.
7.
8.
Objective: To assess the quality of images and video clips of fetal central nervous (CNS) structures obtained by ultrasound and transmitted via tele-ultrasound from Brazil to Australia.

Methods: In this cross-sectional study, 15 normal singleton pregnant women between 20 and 26 weeks were selected. Fetal CNS structures were obtained by images and video clips. The exams were transmitted in real-time using a broadband internet and an inexpensive video streaming device. Four blinded examiners evaluated the quality of the exams using the Likert scale. We calculated the mean, standard deviation, mean difference, and p values were obtained from paired t tests.

Results: The quality of the original video clips was slightly better than that observed by the transmitted video clips; mean difference considering all observers = 0.23 points. In 47/60 comparisons (78.3%; 95% CI?=?66.4–86.9%) the quality of the video clips were judged to be the same. In 182/240 still images (75.8%; 95% CI?=?70.0–80.8%) the scores of transmitted image were considered the same as the original.

Conclusion: We demonstrated that long distance tele-ultrasound transmission of fetal CNS structures using an inexpensive video streaming device provided images of subjective good quality.  相似文献   
9.
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