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   257265篇
  免费   12973篇
  国内免费   2212篇
耳鼻咽喉   3265篇
儿科学   7689篇
妇产科学   5065篇
基础医学   36530篇
口腔科学   5794篇
临床医学   21560篇
内科学   55455篇
皮肤病学   6533篇
神经病学   22051篇
特种医学   8070篇
外国民族医学   115篇
外科学   31475篇
综合类   4410篇
现状与发展   6篇
一般理论   64篇
预防医学   22664篇
眼科学   5104篇
药学   18774篇
  15篇
中国医学   1691篇
肿瘤学   16120篇
  2023年   1550篇
  2022年   1624篇
  2021年   4439篇
  2020年   2845篇
  2019年   4529篇
  2018年   8204篇
  2017年   5517篇
  2016年   5503篇
  2015年   6400篇
  2014年   6933篇
  2013年   10191篇
  2012年   17572篇
  2011年   17603篇
  2010年   8973篇
  2009年   6786篇
  2008年   14896篇
  2007年   15851篇
  2006年   14642篇
  2005年   14628篇
  2004年   13244篇
  2003年   12146篇
  2002年   11456篇
  2001年   6645篇
  2000年   6843篇
  1999年   6190篇
  1998年   1453篇
  1997年   1332篇
  1996年   1170篇
  1995年   1076篇
  1994年   931篇
  1992年   3482篇
  1991年   3108篇
  1990年   2954篇
  1989年   2734篇
  1988年   2563篇
  1987年   2377篇
  1986年   2241篇
  1985年   2041篇
  1984年   1460篇
  1983年   1243篇
  1979年   1217篇
  1978年   856篇
  1977年   813篇
  1975年   815篇
  1974年   987篇
  1973年   997篇
  1972年   936篇
  1971年   922篇
  1970年   862篇
  1969年   905篇
排序方式: 共有10000条查询结果,搜索用时 0 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