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   2884篇
  免费   158篇
  国内免费   17篇
耳鼻咽喉   26篇
儿科学   69篇
妇产科学   104篇
基础医学   300篇
口腔科学   47篇
临床医学   261篇
内科学   901篇
皮肤病学   55篇
神经病学   144篇
特种医学   41篇
外科学   518篇
综合类   62篇
预防医学   172篇
眼科学   73篇
药学   157篇
中国医学   13篇
肿瘤学   116篇
  2023年   29篇
  2022年   59篇
  2021年   113篇
  2020年   54篇
  2019年   91篇
  2018年   113篇
  2017年   58篇
  2016年   86篇
  2015年   73篇
  2014年   115篇
  2013年   129篇
  2012年   214篇
  2011年   217篇
  2010年   110篇
  2009年   114篇
  2008年   171篇
  2007年   180篇
  2006年   157篇
  2005年   178篇
  2004年   169篇
  2003年   129篇
  2002年   122篇
  2001年   33篇
  2000年   21篇
  1999年   26篇
  1998年   22篇
  1997年   15篇
  1996年   17篇
  1995年   15篇
  1994年   14篇
  1993年   15篇
  1992年   35篇
  1991年   32篇
  1990年   19篇
  1989年   12篇
  1988年   22篇
  1987年   9篇
  1986年   4篇
  1985年   6篇
  1984年   10篇
  1983年   6篇
  1982年   4篇
  1980年   2篇
  1977年   4篇
  1975年   4篇
  1973年   2篇
  1972年   2篇
  1968年   6篇
  1967年   7篇
  1966年   3篇
排序方式: 共有3059条查询结果,搜索用时 609 毫秒
81.

Background:

Clinical outcomes of percutaneous coronary intervention (PCI) in patients with saphenous vein grafts (SVGs) remain poor despite the use of drug‐eluting stents (DES). There is a disparity in clinical outcomes in SVG PCI based on various registries, and randomized clinical data remain scant. We conducted a meta‐analysis of all existing randomized controlled trials (RCTS) comparing bare‐metal stents (BMS) and DES in SVGPCIs.

Hypothesis:

PCI in patients with SVG disease using DES may reduce need for repeat revascularization without an excess mortality when compared to BMS.

Methods:

An aggregate data meta‐analysis of clinical outcomes in RCTs comparing PCI with DES vs BMS for SVGs reporting at least 12 months of follow‐up was performed. A literature search between Janurary 1, 2003 and September 30, 2011 identified 4 RCTs (812 patients; DES = 416, BMS = 396). Summary odds ratio (OR) and 95% confidence interval (CI) were calculated using the random‐effects model. The primary endpoint was all‐cause mortality. Secondary outcomes included nonfatal myocardial infarction (MI), repeat revascularization, and major adverse cardiac events (MACE). These outcomes were assessed in a cumulative fashion at 30 days, 18 months, and 36 months.

Results:

There were no intergroup differences in baseline clinical and sociodemographic characteristics. At a median follow‐up of 25 months, patients in the DES and BMS group had similar rates of death (OR: 1.63, 95% CI: 0.45–5.92), MI (OR; 0.83, 95% CI: 0.27‐2.60), and MACE (OR: 0.58, 95% CI: 0.25–1.32). Patients treated with DES had lower rates of repeat revascularization (OR: 0.40, 95% CI: 0.22–0.75).

Conclusions:

In this comprehensive meta‐analysis of all RCTs comparing clinical outcomes of PCI using DES vs BMS in patients with SVG disease, use of DES was associated with a reduction in rate of repeat revascularization and no difference in rates of all‐cause death and MI. Clin. Cardiol. 2012 DOI: 10.1002/clc.21984 Dr. Virani is supported by a Department of Veterans Affairs Health Services Research and Development Service (HSR&D) Career Development Award (CDA‐09‐028), and has research support from Merck and National Football League Charities (all grants to the institution and not individual). The views expressed in this article are those of the authors and do not necessarily represent the views of the Department of Veterans Affairs. The authors have no other funding, financial relationships, or conflicts of interest to disclose.  相似文献   
82.
83.
84.
The association between preoperative use of angiotensin-converting enzyme (ACE) inhibitors and outcomes after coronary artery bypass grafting (CABG) remain controversial. Our aim was to study in-hospital outcomes after isolated CABG in patients on preoperative ACE inhibitors. A retrospective analysis of 8,889 patients who underwent isolated CABG from 2000 through 2011 was conducted. The primary outcome of interest was the incidence of major adverse events (MAEs) defined as a composite of mortality, postoperative renal dysfunction, myocardial infarction, stroke, and atrial fibrillation during index hospitalization. The secondary outcome was the incidence of individual outcomes included in MAEs. Logistic regression analyses were performed. Of 8,889 patients, 3,983 (45%) were on preoperative ACE inhibitors and 4,906 (55%) were not. Overall incidence of MAEs was 38.1% (n = 1,518) in the ACE inhibitor group compared to 33.6% (n = 1,649) in the no-ACE inhibitor group. Preoperative use of ACE inhibitors was independently associated with MAEs (odds ratio 1.13, 95% confidence interval 1.03 to 1.24), most of which was driven by a statistically significant increase in postoperative renal dysfunction (odds ratio 1.18, 95% confidence interval 1.03 to 1.36) and atrial fibrillation (odds ratio 1.15, 95% confidence interval 1.05 to 1.27). In-hospital mortality, postoperative myocardial infarction, and stroke were not significantly associated with preoperative ACE inhibitor use. Analyses performed after excluding patients with low ejection fractions yielded similar results. In conclusion, preoperative ACE inhibitor use was associated with an increased risk of MAEs after CABG, in particular postoperative renal dysfunction and atrial fibrillation.  相似文献   
85.
ABSTRACT: Canalicular adenomas are uncommon, benign epithelial neoplasm of the salivary glands that usually involve the upper lip and the buccal mucosa of elderly people. Differential diagnosis of the canalicular adenoma versus adenocarcinoma is important because it may result in unjustified radiotherapy or extensive and aggressive surgery. Despite the benign nature of canalicular adenomas, complete surgical removal and a regular clinical follow-up are recommended. The current study describes the diagnostic procedures, surgical management, and follow-up of a canalicular adenoma involving the palate of a 79-year-old man.  相似文献   
86.
87.
88.
89.
Despite the high incidence, the molecular events involved in intestinal-type gastric carcinogenesis remains unclear. We previously established an intestinal-type gastric carcinogenesis model in Cebus apella, a New World monkey. In the present study, we evaluated hTERT and TP53 mRNA expression, as well as their protein immunoreactivity, in normal mucosa, non-atrophic gastritis, atrophic gastritis, intestinal metaplasia, and intestinal-type gastric cancer samples of non-human primates treated with N-methyl-nitrosourea. In addition, we evaluated the number of TP53 copies in these samples. Although hTERT immunoreactivity was only detected in gastric cancer, a continuous increase of hTERT mRNA expression was observed from non-atrophic gastritis to gastric tumors. No sample presented p53 immunoreactivity. However, we also observed a continuous decrease of TP53 mRNA expression during the sequential steps of gastric carcinogenesis. Moreover, loss of TP53 copies was observed in intestinal metaplasia and gastric cancer samples. Our study highlights that hTERT and TP53 have a key role in intestinal-type gastric cancer initiation.  相似文献   
90.
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