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   237129篇
  免费   11199篇
  国内免费   416篇
耳鼻咽喉   3108篇
儿科学   7423篇
妇产科学   4816篇
基础医学   33959篇
口腔科学   5691篇
临床医学   18684篇
内科学   52447篇
皮肤病学   6295篇
神经病学   21025篇
特种医学   7350篇
外国民族医学   101篇
外科学   29277篇
综合类   994篇
一般理论   63篇
预防医学   21488篇
眼科学   4626篇
药学   16581篇
中国医学   713篇
肿瘤学   14103篇
  2023年   1273篇
  2022年   935篇
  2021年   3562篇
  2020年   2124篇
  2019年   3966篇
  2018年   7525篇
  2017年   4930篇
  2016年   4922篇
  2015年   5535篇
  2014年   5787篇
  2013年   9333篇
  2012年   16226篇
  2011年   16184篇
  2010年   8078篇
  2009年   6067篇
  2008年   13866篇
  2007年   14857篇
  2006年   13655篇
  2005年   13532篇
  2004年   12672篇
  2003年   11538篇
  2002年   10933篇
  2001年   6150篇
  2000年   6233篇
  1999年   5560篇
  1998年   989篇
  1997年   815篇
  1996年   785篇
  1995年   697篇
  1992年   3210篇
  1991年   2878篇
  1990年   2750篇
  1989年   2534篇
  1988年   2389篇
  1987年   2237篇
  1986年   2112篇
  1985年   1916篇
  1984年   1419篇
  1983年   1204篇
  1979年   1211篇
  1978年   862篇
  1977年   813篇
  1975年   814篇
  1974年   985篇
  1973年   994篇
  1972年   935篇
  1971年   923篇
  1970年   863篇
  1969年   905篇
  1968年   789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