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   356065篇
  免费   15698篇
  国内免费   620篇
耳鼻咽喉   4719篇
儿科学   10678篇
妇产科学   7873篇
基础医学   51874篇
口腔科学   9343篇
临床医学   25330篇
内科学   77747篇
皮肤病学   9376篇
神经病学   30937篇
特种医学   10224篇
外国民族医学   102篇
外科学   42765篇
综合类   1533篇
一般理论   81篇
预防医学   35782篇
眼科学   8106篇
药学   26249篇
中国医学   1174篇
肿瘤学   18490篇
  2023年   1815篇
  2022年   1259篇
  2021年   5124篇
  2020年   3019篇
  2019年   5786篇
  2018年   10760篇
  2017年   6957篇
  2016年   7034篇
  2015年   7851篇
  2014年   8381篇
  2013年   13389篇
  2012年   22944篇
  2011年   23294篇
  2010年   11625篇
  2009年   8711篇
  2008年   19818篇
  2007年   21198篇
  2006年   19861篇
  2005年   19487篇
  2004年   18261篇
  2003年   16796篇
  2002年   16079篇
  2001年   9881篇
  2000年   10396篇
  1999年   8706篇
  1998年   1477篇
  1992年   5040篇
  1991年   4515篇
  1990年   4417篇
  1989年   3918篇
  1988年   3720篇
  1987年   3441篇
  1986年   3390篇
  1985年   3122篇
  1984年   2298篇
  1983年   1972篇
  1979年   2264篇
  1978年   1548篇
  1977年   1474篇
  1976年   1292篇
  1975年   1587篇
  1974年   1992篇
  1973年   2052篇
  1972年   1913篇
  1971年   1867篇
  1970年   1752篇
  1969年   1875篇
  1968年   1790篇
  1967年   1555篇
  1966年   1404篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.

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   
3.
4.
5.
6.
7.
8.
9.
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   
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