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   298452篇
  免费   14402篇
  国内免费   721篇
耳鼻咽喉   3775篇
儿科学   8987篇
妇产科学   6479篇
基础医学   42691篇
口腔科学   8116篇
临床医学   23685篇
内科学   66098篇
皮肤病学   7874篇
神经病学   26853篇
特种医学   8997篇
外国民族医学   106篇
外科学   35864篇
综合类   1341篇
一般理论   91篇
预防医学   27925篇
眼科学   5598篇
药学   20993篇
中国医学   963篇
肿瘤学   17139篇
  2023年   1727篇
  2022年   2373篇
  2021年   5997篇
  2020年   3429篇
  2019年   5858篇
  2018年   10782篇
  2017年   7050篇
  2016年   6513篇
  2015年   7250篇
  2014年   8376篇
  2013年   12627篇
  2012年   20471篇
  2011年   20624篇
  2010年   10736篇
  2009年   8494篇
  2008年   17295篇
  2007年   18222篇
  2006年   16739篇
  2005年   16390篇
  2004年   15320篇
  2003年   13982篇
  2002年   13141篇
  2001年   7049篇
  2000年   7163篇
  1999年   6340篇
  1998年   1454篇
  1997年   1172篇
  1996年   1062篇
  1995年   959篇
  1992年   3619篇
  1991年   3199篇
  1990年   3062篇
  1989年   2798篇
  1988年   2593篇
  1987年   2464篇
  1986年   2309篇
  1985年   2102篇
  1984年   1578篇
  1983年   1330篇
  1979年   1356篇
  1978年   971篇
  1977年   905篇
  1975年   914篇
  1974年   1096篇
  1973年   1116篇
  1972年   1048篇
  1971年   1019篇
  1970年   944篇
  1969年   979篇
  1968年   881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.
Abstract

Objectives: This study examined word use as an indicator of interpersonal positive reframing in daily conversations of couples coping with breast cancer and as a predictor of stress.

Design: The Electronically Activated Recorder (EAR) and Linguistic Inquiry and Word Count (LIWC) were used to examine naturally occurring word use conceptually linked to positive reframing (positive emotion, negative emotion, and cognitive processing words).

Sample: Fifty-two couples coping with breast cancer.

Methods: Couples wore the EAR, a device participants wear, that audio-recorded over one weekend (>16,000 sound files), and completed self-reports of positive reframing (COPE) and stress (Perceived Stress Scale). LIWC, a software program, measured word use.

Findings: Both partners’ word use (i.e., positive emotion and cognitive processing words) was associated with their own reported positive reframing, and spouses’ word use was also indicative of patients’ positive reframing. Results also revealed that, in general, words indicating positive reframing predicted lower levels of stress.

Conclusions: Findings supported the hypothesis that partners—and particularly spouses of breast cancer patients—may assist each other’s coping by positively reframing the cancer experience and other negative experiences in conversation.  相似文献   
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