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   342077篇
  免费   15911篇
  国内免费   671篇
耳鼻咽喉   4576篇
儿科学   10422篇
妇产科学   7548篇
基础医学   48625篇
口腔科学   8814篇
临床医学   25619篇
内科学   76946篇
皮肤病学   9509篇
神经病学   29759篇
特种医学   9719篇
外国民族医学   102篇
外科学   41685篇
综合类   1689篇
一般理论   98篇
预防医学   32290篇
眼科学   7093篇
药学   24168篇
中国医学   1208篇
肿瘤学   18789篇
  2023年   1882篇
  2022年   1851篇
  2021年   5979篇
  2020年   3388篇
  2019年   6518篇
  2018年   11034篇
  2017年   7069篇
  2016年   6978篇
  2015年   7923篇
  2014年   8978篇
  2013年   13911篇
  2012年   23295篇
  2011年   23793篇
  2010年   12083篇
  2009年   9225篇
  2008年   20090篇
  2007年   21542篇
  2006年   19814篇
  2005年   19727篇
  2004年   18148篇
  2003年   16801篇
  2002年   15892篇
  2001年   9123篇
  2000年   9729篇
  1999年   8228篇
  1998年   1547篇
  1997年   1225篇
  1996年   1115篇
  1995年   1004篇
  1992年   4301篇
  1991年   3772篇
  1990年   3576篇
  1989年   3178篇
  1988年   2933篇
  1987年   2750篇
  1986年   2643篇
  1985年   2366篇
  1984年   1753篇
  1983年   1460篇
  1979年   1535篇
  1978年   1066篇
  1977年   988篇
  1975年   1060篇
  1974年   1266篇
  1973年   1314篇
  1972年   1216篇
  1971年   1213篇
  1970年   1124篇
  1969年   1177篇
  1968年   1042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.
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