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   143304篇
  免费   11328篇
  国内免费   3435篇
耳鼻咽喉   1201篇
儿科学   2872篇
妇产科学   2044篇
基础医学   11231篇
口腔科学   2771篇
临床医学   17642篇
内科学   17237篇
皮肤病学   1279篇
神经病学   12102篇
特种医学   3959篇
外国民族医学   10篇
外科学   11016篇
综合类   21339篇
现状与发展   8篇
一般理论   1篇
预防医学   23993篇
眼科学   1271篇
药学   15887篇
  212篇
中国医学   6604篇
肿瘤学   5388篇
  2024年   498篇
  2023年   2814篇
  2022年   5410篇
  2021年   7016篇
  2020年   6687篇
  2019年   5605篇
  2018年   5421篇
  2017年   4923篇
  2016年   5106篇
  2015年   4935篇
  2014年   10533篇
  2013年   10516篇
  2012年   9174篇
  2011年   9798篇
  2010年   7547篇
  2009年   7297篇
  2008年   7153篇
  2007年   6937篇
  2006年   5798篇
  2005年   4914篇
  2004年   3976篇
  2003年   3384篇
  2002年   2552篇
  2001年   2262篇
  2000年   1864篇
  1999年   1664篇
  1998年   1465篇
  1997年   1379篇
  1996年   1166篇
  1995年   1082篇
  1994年   1026篇
  1993年   861篇
  1992年   816篇
  1991年   758篇
  1990年   615篇
  1989年   537篇
  1988年   526篇
  1987年   484篇
  1986年   443篇
  1985年   588篇
  1984年   501篇
  1983年   308篇
  1982年   328篇
  1981年   301篇
  1980年   283篇
  1979年   172篇
  1978年   173篇
  1977年   145篇
  1976年   105篇
  1974年   53篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
21.
22.
23.
Academic output is just one aspect of a successful career as a plastic surgeon. However, for those with a strong interest in academia, the academic output of a department will likely be a key factor when deciding how to rank jobs. The aim of this study was to quantify and rank the academic output of plastic surgery units across the UK and Ireland. The Institute for Scientific Information (ISI) Web of Science Bibliometric analysis tool was used to collate cumulative (1950–2016), 10 year (2006–2016) and 3 years (2013–2015) research output data for plastic surgery units in the UK and Ireland. Sixty-six plastic surgery units were identified. Departments were ranked for each time period according to the number of papers produced, number of citations (Nc) and h-index (a measure of the impact of scientific output). The top 3 departments for number of papers in the last 10 years were The Royal Free Hospital, London (226) Broomfield Hospital, Chelmsford (218), and Morriston Hospital and Swansea (188). The top 3 for h-number were The Royal Free Hospital (21) Wythenshawe Hospital, Manchester (18) and Morriston Hospital (17). Academic output varies across plastic surgery units in the UK and Ireland. A number of departments have consistently maintained high academic outputs across the years and will be of interest to surgeons hoping to pursue a career in academia.  相似文献   
24.
《Journal of Evidence》2019,19(2):131-139
ObjectivesThe aims of this article are to identify all the published systematic reviews (SRs) and meta-analyses (MAs) that studied the relationship between periodontal and systemic diseases and to assess their quality using 2 scales (the Overview Quality Assessment Questionnaire [OQAQ] and A Measurement Tool to Assess Systematic Reviews [AMSTAR] checklist).MethodsFor SRs and MAs to be included, they should have investigated one of the following systemic diseases: pulmonary conditions, cardiac conditions, endocrine conditions, cancer, blood disorders, psychological conditions, anxiety, depression, mood disorders, and several other diseases. Two investigators screened MEDLINE via PubMed, Embase, Scopus, Web of Science, and the Cochrane Database of Systematic Reviews. The tools used to evaluate quality were the AMSTAR scale and OQAQ. The protocol was prospectively registered in PROSPERO (CRD42018102208).ResultsThe search strategy found 691 unique articles, 42 of which met the eligibility criteria and were included in this review. Diabetes mellitus was the most investigated disease (14 out of 42 studies), followed by obesity (11 studies) and cardiovascular diseases (5 studies). A total of 40 reviews reported on the characteristics of included studies, and, as per the AMSTAR scale, 39 reviews had an a priori design. The number of reviews that fulfilled the status of publication criterion was the lowest (7 reviews only), followed by the number used in the assessment of publication bias (11 reviews). The number of high-quality reviews was higher with the OQAQ than with the AMSTAR checklist (33 vs 25 studies), but the AMSTAR showed a higher number of medium-quality reviews than the OQAQ (14 vs 6 studies). Both showed the same number of low-quality reviews.ConclusionsHigh-quality SRs and MAs are crucial to understanding the relationship between systemic and periodontal diseases. Medical practitioners must be able to inform patients about oral health and specific periodontal health concerns.  相似文献   
25.
Although an inverse relationship between body mass index (BMI) and baroreflex sensitivity (BRS) was found, the effect of waist circumference (WC) on BRS is still inconclusive. The contradictory results of previous studies may be related to the heterogeneity and relatively small sample size of the subjects examined. The aim of this population-based study was to investigate whether the influence of increased WC is more detrimental to BRS than BMI. A total of 760 community dwellers were recruited and they were classified into Q1 (n = 189), Q2 (n = 183), Q3 (n = 192) and Q4 (n = 196) groups, based on WC quartiles. Spontaneous BRS was determined by spectral α coefficient method. Valsalva ratio was the longest RR interval after release of Valsalva maneuver divided by the shortest RR interval during maneuver. Cardiac autonomic function was calculated by power spectrum of heart rate in low and high frequency (LF, 0.04–0.15 Hz; HF, 0.15–0.40 Hz), and LF/HF ratio in supine position for five minutes. There were significant differences in spontaneous BRS and Valsalva ratio among different WC groups. In multivariate analysis, obesity was inversely associated with spontaneous BRS and Valsalva ratio. However, these inverse relationships became insignificant after further adjustment for WC quartiles. In contrast, Q4 vs. Q1, Q3 vs. Q1 and Q2 vs. Q1 of WC were inversely related to spontaneous BRS. Q4 vs. Q1 and Q3 vs. Q1 of WC were negatively associated with the Valsalva ratio. In conclusion, increased and even high-normal WC had a stronger adverse effect on BRS than BMI, independent of cardio-metabolic risk factors.  相似文献   
26.
目的通过Meta分析评价安宁疗护对社区临终患者生活质量的影响。方法计算机检索PubMed、CINAHL、ScienceDirect、MEDLINE、Cochrane Library、SAGE数据库、中国知网、维普中文科技期刊数据库、万方数据库和中国生物医学文献数据库中安宁疗护对社区临终患者的随机对照试验,由2名研究人员独立筛选文献并提取资料,对符合质量标准的随机对照试验进行Meta分析。结果共纳入7篇文献,包括1095名社区临终患者。Meta分析结果显示,安宁疗护可以改善社区临终患者的总体生活质量(SMD=0.48,95%CI0.07~0.88,P=0.02)和情绪功能(SMD=1.27,95%CI0.59~1.95,P<0.001),在改善生活质量的躯体功能、角色功能、认知功能和社会功能水平上差异无统计学意义(P>0.05)。结论安宁疗护能改善社区临终患者的总体生活质量和情绪功能,但对生活质量其他功能的改善情况还需要设计更加规范、多中心、大样本的随机对照试验进一步证实。  相似文献   
27.
对当前的疾病预防控制体系和机构面临的体系不健全、政府投入不充分、事业发展不平衡、人才缺失和能力不足、缺乏系统的理论指导、体系的碎片化严重、与社会经济发展的战略衔接不力、机构内部内生动力和活力不足以及体系治理能力不足等问题做了讨论分析,以期进一步分析在健康中国战略和事业单位机构改革等宏观环境变化所带来的机遇以及疾控体系的发展策略和具体措施,促进疾病预防控制事业在改革中谋发展。  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