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   8083篇
  免费   497篇
  国内免费   46篇
耳鼻咽喉   121篇
儿科学   176篇
妇产科学   147篇
基础医学   1016篇
口腔科学   273篇
临床医学   536篇
内科学   1623篇
皮肤病学   198篇
神经病学   625篇
特种医学   309篇
外国民族医学   2篇
外科学   1279篇
综合类   137篇
一般理论   5篇
预防医学   553篇
眼科学   356篇
药学   782篇
中国医学   67篇
肿瘤学   421篇
  2023年   90篇
  2022年   88篇
  2021年   259篇
  2020年   222篇
  2019年   307篇
  2018年   405篇
  2017年   260篇
  2016年   315篇
  2015年   328篇
  2014年   481篇
  2013年   595篇
  2012年   832篇
  2011年   831篇
  2010年   483篇
  2009年   340篇
  2008年   531篇
  2007年   507篇
  2006年   392篇
  2005年   327篇
  2004年   243篇
  2003年   253篇
  2002年   190篇
  2001年   45篇
  2000年   35篇
  1999年   40篇
  1998年   27篇
  1997年   14篇
  1996年   14篇
  1995年   15篇
  1994年   15篇
  1993年   13篇
  1992年   12篇
  1991年   11篇
  1990年   4篇
  1989年   12篇
  1988年   12篇
  1987年   5篇
  1986年   2篇
  1985年   6篇
  1984年   8篇
  1982年   8篇
  1981年   5篇
  1980年   4篇
  1979年   7篇
  1978年   6篇
  1977年   3篇
  1976年   7篇
  1975年   7篇
  1974年   6篇
  1960年   1篇
排序方式: 共有8626条查询结果,搜索用时 15 毫秒
1.

Psychometrically sound resilience outcome measures are essential to establish how health and care services or interventions can enhance the resilience of people living with dementia (PLWD) and their carers. This paper systematically reviews the literature to identify studies that administered a resilience measurement scale with PLWD and/or their carers and examines the psychometric properties of these measures. Electronic abstract databases and the internet were searched, and an international network contacted to identify peer-reviewed journal articles. Two authors independently extracted data. They critically reviewed the measurement properties from the available psychometric data in the studies, using a standardised checklist adapted for purpose. Fifty-one studies were included in the final review, which applied nine different resilience measures, eight developed in other populations and one developed for dementia carers in Thailand. None of the measures were developed for use with people living with dementia. The majority of studies (N?=?47) focussed on dementia carers, three studies focussed on people living with dementia and one study measured both carers and the person with dementia. All the studies had missing information regarding the psychometric properties of the measures as applied in these two populations. Nineteen studies presented internal consistency data, suggesting seven of the nine measures demonstrate acceptable reliability in these new populations. There was some evidence of construct validity, and twenty-eight studies hypothesised effects a priori (associations with other outcome measure/demographic data/differences in scores between relevant groups) which were partially supported. The other studies were either exploratory or did not specify hypotheses. This limited evidence does not necessarily mean the resilience measure is not suitable, and we encourage future users of resilience measures in these populations to report information to advance knowledge and inform further reviews. All the measures require further psychometric evaluation in both these populations. The conceptual adequacy of the measures as applied in these new populations was questionable. Further research to understand the experience of resilience for people living with dementia and carers could establish the extent current measures -which tend to measure personal strengths -are relevant and comprehensive, or whether further work is required to establish a new resilience outcome measure.

  相似文献   
2.
3.
Prior studies have conflicting findings regarding the association between gastroesophageal reflux disease (GERD) and esophageal squamous cell carcinoma (ESCC). We examined this relationship in a prospective cohort in a region of high ESCC incidence. Baseline exposure data were collected from 50 045 individuals using in-person interviews at the time of cohort entry. Participants were followed until they developed cancer, died, or were lost to follow up. Participants with GERD symptoms were categorized into any GERD (heartburn or regurgitation), mixed symptoms, or heartburn alone. Multivariable Cox regression was used to assess the relationship between GERD symptom group and histologically confirmed ESCC. The model was adjusted for known risk factors for GERD and ESCC. 49 559 individuals were included in this study, of which 9005 had GERD symptoms. Over 13.0 years of median follow up, 290 individuals were diagnosed with ESCC. We found no association between any GERD and risk of ESCC (aHR 0.90, 95% CI: 0.66-1.24, P = .54). Similar findings were observed for the GERD symptom subtypes. Significant interactions between any GERD and sex (P = .013) as well as tobacco smoking (P = .028) were observed. In post-hoc analyses, GERD was associated with a decreased risk of ESCC in men (aHR 0.51, 95% CI: 0.27-0.98 P = .04) and in smokers (aHR 0.26, 95% CI: 0.08-0.83 P = .02). While there was little evidence for an overall association between GERD symptoms and ESCC risk, significant interactions with sex and smoking were observed. Men and smokers with GERD symptoms had a lower risk of ESCC development.  相似文献   
4.
5.
Background

The aim of this study was to evaluate the effects of multi-walled carbon nanotubes/hydroxyapatite (MWCNT/HA) granules with or without leukocyte- and platelet-rich fibrin (L-PRF) on bone regeneration in cancellous bone of sheep model.

Methods

Totally, 32 cylindrical holes were drilled in female sheep (n?=?4) in the distal epiphysis and proximal metaphysis of right and left humerus and femur. The defects were randomly filled with (1) MWCNT/HA, (2) MWCNT/HA mixed with L-PRF, (3) L-PRF, and (4) left empty as control. After 8 weeks, defects were evaluated and compared radiographically using multi-slice computed tomographic (CT) scan and cone beam CT scans, histologically and histomorphometrically.

Results

The results showed that there was no significant inflammation (>?10%) or foreign body reaction around the granules. The new lamellar bone was regenerated around the MWCNT/HA nanocomposite granules. Addition of L-PRF to MWCNT/HA demonstrated significantly improvement of new bone formation, about 27.40?±?1.08%, in comparison with the L-PRF alone, about (12.16?±?1.46%) (P?<?0.01). Also, the rate of new bone formation was significantly greater with the use of MWCNT/HA granules (24.59?±?1.54%) compared to the control (10.36?±?1.17%) (P?<?0.01).

Conclusion

Consequently, both biocompatibility and osteoconductivity of MWCNT/HA nanocomposite were demonstrated in the preclinical sheep model, and the use of L-PRF in combination with MWCNT/HA nanocomposite can improve bone regeneration.

  相似文献   
6.
7.
8.
9.
Inflammation Research - Among the countless endeavours made at elucidating the pathogenesis of COVID-19, those aimed at the histopathological alterations of type 2 alveolar epithelial cells (AT2)...  相似文献   
10.
Millions of cataract surgeries with intraocular lens (IOL) implantation are performed worldwide. Although cataract surgery brings many benefits to the patients, the risk of various complications is still a concern. One of the infrequent adverse events but potentially affecting on patients’ visual acuity and contrast sensitivity is losing the transparency of IOL. IOL opacification may lead to IOL removal or exchange, which is unpleasant to both the patient and the surgeon. Several reports of acute IOL clouding are available in the literature describing various etiologies of this phenomenon, however, the exact mechanism remained unclear in some cases. Herein, we aimed to review the causes and outcomes of intraoperative and early postoperative IOL opacification.  相似文献   
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