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   1527篇
  免费   68篇
  国内免费   10篇
耳鼻咽喉   29篇
儿科学   34篇
妇产科学   25篇
基础医学   232篇
口腔科学   48篇
临床医学   127篇
内科学   252篇
皮肤病学   13篇
神经病学   86篇
特种医学   199篇
外科学   276篇
综合类   10篇
预防医学   56篇
眼科学   27篇
药学   101篇
中国医学   4篇
肿瘤学   86篇
  2023年   7篇
  2022年   13篇
  2021年   38篇
  2020年   26篇
  2019年   32篇
  2018年   43篇
  2017年   25篇
  2016年   32篇
  2015年   43篇
  2014年   59篇
  2013年   73篇
  2012年   121篇
  2011年   156篇
  2010年   90篇
  2009年   68篇
  2008年   116篇
  2007年   112篇
  2006年   121篇
  2005年   115篇
  2004年   92篇
  2003年   73篇
  2002年   56篇
  2001年   3篇
  2000年   1篇
  1999年   3篇
  1998年   12篇
  1997年   17篇
  1996年   12篇
  1995年   8篇
  1994年   7篇
  1993年   3篇
  1992年   1篇
  1991年   6篇
  1990年   1篇
  1989年   3篇
  1988年   3篇
  1987年   1篇
  1986年   2篇
  1985年   1篇
  1983年   2篇
  1982年   1篇
  1981年   1篇
  1979年   1篇
  1978年   2篇
  1976年   1篇
  1970年   1篇
  1967年   1篇
排序方式: 共有1605条查询结果,搜索用时 140 毫秒
21.
Evolution of communication systems, especially internet-based technologies, has probably affected Radiology more than any other medical specialty. Tremendous increase in internet bandwidth has enabled a true revolution in image transmission and easy remote viewing of the static images and real-time video stream. Previous reports of real-time telesonography, such as the ones developed for emergency situations and humanitarian work, rely on high compressions of images utilized by remote sonologist to guide and supervise the unexperienced examiner. We believe that remote sonology could be also utilized in teleultrasound exam of infant hip. We tested feasibility of a low-cost teleultrasound system for infant hip and performed data analysis on the transmitted and original images. Transmission of data was accomplished with Remote Ultrasound (RU), a software package specifically designed for teleultrasound transmission through limited internet bandwidth. While image analysis of image pairs revealed statistically significant loss of information, panel evaluation failed to recognize any clinical difference between the original saved and transmitted still images.  相似文献   
22.
23.
ObjectiveMany studies have reported insufficient support from surgical services, resulting in nephrologists creating arteriovenous fistulas in many centers. The aim of this study was to compare risk factors of arteriovenous fistula dysfunction in patients whose fistulas were created by nephrologists versus vascular surgeons.MethodsThis was a retrospective, analytical study of interventions by nephrologists and vascular surgeons during a period of 15 years. Out of a total of 1,048 fistulas, 764 (72.9%) were created by nephrologists patients, while vascular surgeons were responsible for 284 (27.1%) fistulae. Laboratory, demographic, and clinical parameters which might affect functioning of these arteriovenous fistulae were analyzed.ResultsPatients whose arteriovenous fistula was formed by nephrologists differed significantly from those created by vascular surgeons in relation to the preventive character of the arteriovenous fistula (p = 0.011), lumen of the vein (p < 0.001) and systolic blood pressure (p = 0.047). Multivariate logistic regression of arteriovenous fistula dysfunction showed that risk factors were female gender (odds ratio [OR] = 1.56, 95% CI 1.16–2.07), whether the fistulae were created by vascular surgeons or nephrologists (OR = 1.38; 95% CI 1.01–1.89) and the site of the arteriovenous fistula (OR = 0.64; 95% CI 0.48–0.85).ConclusionsArteriovenous fistulae created by vascular surgeons, female gender, and the location are risk factors of dysfunction.  相似文献   
24.
25.
26.

Purpose

The aim of this research was to investigate the association of chronic and aggressive periodontitis with the severity of coronary artery disease which was angiographically verified.

Material and methods

Subjects were selected among the hospitalized patients at the University Hospital Centre Zagreb who had coronary angiography done because of the chest pain. Thorough clinical examination included periodontal indices and clinical and socio-demographic characteristics of participants. Subjects were divided in two test groups, acute coronary syndrome (ACS) and stable coronary artery disease (CAD), and the control group with no significant CAD. Data were analyzed using Kruskal-Wallis and Pearson’s Chi-Square test.

Results

From 106 subjects, 66 (62.3%) were hospitalized for ACS, 22 (20.7%) had stable CAD and only 18 (17.0%) had no significant CAD. Only 26 (24.5%) out of 106 patients were never smokers (p<0.05). Chronic periodontitis was the most common finding with 68.2% in ACS group and 54.5% in stable CAD group, while healthy patients without periodontitis (72.6%) were dominant in the control group (p<0.001). Stable CAD group had the highest mean probing depth (PD) 3.92±1.16, gingival recession (GR) 1.34±0.78, clinical attachment level (CAL) 4.60±1.41 and bleeding on probing (BOP) 45.98±26.19 values, whereas ACS group had mean PD value of 3.77±0.91, GR 1.11±0.66, CAL 4.32±1.08 and BOP 41.30±22.09, and no significant CAD group had mean PD value of 3.27±0.97, GR 0.69±0.37, CAL 3.62±1.04 and BOP 26.39±13.92 (p<0.05).

Conclusion

Periodontitis was shown to be associated with angiographically verified coronary artery disease. Physical inactivity, poor oral hygiene and periodontal inflammation were observed in patients with ACS and stable CAD.Key words: Periodontitis, Periodontal Index, Cardiovascular Diseases, Coronary Artery Disease, Coronary Angiography  相似文献   
27.
We aimed to investigate whether the expression of the OPG/RANK/RANKL triad in peripheral blood mononuclear cells (PBMC) and circulating levels of markers of ectopic mineralization (OPG, FGF-23, PPi) are modified in patients with calcific aortic valve disease (CAVD). We found that patients affected by CAVD (n?=?50) had significantly higher circulating levels of OPG as compared to control individuals (p?=?0.003). No differences between the two groups were found in FGF-23 and PPi levels. RANKL expression was higher in the PBMC from CAVD patients (p?=?0.018) and was directly correlated with the amount of valve calcification (p?=?0.032). In vitro studies showed that treatment of valve interstitial cells (VIC) with RANKL plus phosphate was followed by increase in matrix mineralization (p?=?0.001). In conclusion, RANKL expression is increased in PBMC of patients with CAVD, is directly correlated with the degree of valve calcification, and promotes pro-calcific differentiation of VIC.  相似文献   
28.
29.
30.
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