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   243314篇
  免费   11644篇
  国内免费   491篇
耳鼻咽喉   3189篇
儿科学   7697篇
妇产科学   4962篇
基础医学   34761篇
口腔科学   5821篇
临床医学   19510篇
内科学   53486篇
皮肤病学   6490篇
神经病学   21681篇
特种医学   7401篇
外国民族医学   104篇
外科学   30110篇
综合类   1265篇
一般理论   67篇
预防医学   22057篇
眼科学   4715篇
药学   16938篇
  4篇
中国医学   808篇
肿瘤学   14383篇
  2023年   1339篇
  2022年   1096篇
  2021年   3850篇
  2020年   2308篇
  2019年   4148篇
  2018年   7712篇
  2017年   5115篇
  2016年   5112篇
  2015年   5747篇
  2014年   6145篇
  2013年   9672篇
  2012年   16529篇
  2011年   16491篇
  2010年   8353篇
  2009年   6314篇
  2008年   14061篇
  2007年   15119篇
  2006年   13911篇
  2005年   13794篇
  2004年   12954篇
  2003年   11846篇
  2002年   11164篇
  2001年   6343篇
  2000年   6386篇
  1999年   5699篇
  1998年   1028篇
  1997年   848篇
  1996年   787篇
  1992年   3295篇
  1991年   2960篇
  1990年   2816篇
  1989年   2563篇
  1988年   2444篇
  1987年   2250篇
  1986年   2144篇
  1985年   1920篇
  1984年   1447篇
  1983年   1227篇
  1982年   708篇
  1979年   1251篇
  1978年   889篇
  1977年   827篇
  1975年   831篇
  1974年   1023篇
  1973年   1046篇
  1972年   961篇
  1971年   959篇
  1970年   891篇
  1969年   928篇
  1968年   797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.
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   
8.
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