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   79409篇
  免费   8660篇
  国内免费   334篇
耳鼻咽喉   884篇
儿科学   1856篇
妇产科学   2518篇
基础医学   7300篇
口腔科学   1410篇
临床医学   21466篇
内科学   14709篇
皮肤病学   1101篇
神经病学   6696篇
特种医学   2136篇
外科学   11311篇
综合类   671篇
一般理论   70篇
预防医学   6065篇
眼科学   1290篇
药学   3731篇
  1篇
中国医学   66篇
肿瘤学   5122篇
  2023年   1017篇
  2022年   317篇
  2021年   1384篇
  2020年   1284篇
  2019年   1386篇
  2018年   2498篇
  2017年   2405篇
  2016年   2627篇
  2015年   2842篇
  2014年   3479篇
  2013年   4486篇
  2012年   4787篇
  2011年   5488篇
  2010年   3625篇
  2009年   3740篇
  2008年   4866篇
  2007年   4957篇
  2006年   4873篇
  2005年   4785篇
  2004年   4496篇
  2003年   4256篇
  2002年   3922篇
  2001年   909篇
  2000年   652篇
  1999年   954篇
  1998年   1295篇
  1997年   1270篇
  1996年   1159篇
  1995年   1071篇
  1994年   830篇
  1993年   692篇
  1992年   543篇
  1991年   465篇
  1990年   456篇
  1989年   350篇
  1988年   354篇
  1987年   307篇
  1986年   300篇
  1985年   331篇
  1984年   317篇
  1983年   338篇
  1982年   399篇
  1981年   370篇
  1980年   267篇
  1979年   170篇
  1978年   183篇
  1977年   171篇
  1976年   134篇
  1975年   87篇
  1972年   103篇
排序方式: 共有10000条查询结果,搜索用时 171 毫秒
1.
2.
3.
Patient navigation is a strategy for overcoming barriers to reduce disparities and to improve access and outcomes. The aim of this umbrella review was to identify, critically appraise, synthesize, and present the best available evidence to inform policy and planning regarding patient navigation across the cancer continuum. Systematic reviews examining navigation in cancer care were identified in the Cochrane Central Register of Controlled Trials (CENTRAL), PubMed, Embase, Cumulative Index of Nursing and Allied Health (CINAHL), Epistemonikos, and Prospective Register of Systematic Reviews (PROSPERO) databases and in the gray literature from January 1, 2012, to April 19, 2022. Data were screened, extracted, and appraised independently by two authors. The JBI Critical Appraisal Checklist for Systematic Review and Research Syntheses was used for quality appraisal. Emerging literature up to May 25, 2022, was also explored to capture primary research published beyond the coverage of included systematic reviews. Of the 2062 unique records identified, 61 systematic reviews were included. Fifty-four reviews were quantitative or mixed-methods reviews, reporting on the effectiveness of cancer patient navigation, including 12 reviews reporting costs or cost-effectiveness outcomes. Seven qualitative reviews explored navigation needs, barriers, and experiences. In addition, 53 primary studies published since 2021 were included. Patient navigation is effective in improving participation in cancer screening and reducing the time from screening to diagnosis and from diagnosis to treatment initiation. Emerging evidence suggests that patient navigation improves quality of life and patient satisfaction with care in the survivorship phase and reduces hospital readmission in the active treatment and survivorship care phases. Palliative care data were extremely limited. Economic evaluations from the United States suggest the potential cost-effectiveness of navigation in screening programs.  相似文献   
4.
5.
6.
7.
8.
9.
10.
Prevalence of osteoporosis is more than 50% in older adults, yet current clinical methods for diagnosis that rely on areal bone mineral density (aBMD) fail to detect most individuals who have a fragility fracture. Bone fragility can manifest in different forms, and a “one-size-fits-all” approach to diagnosis and management of osteoporosis may not be suitable. High-resolution peripheral quantitative computed tomography (HR-pQCT) provides additive information by capturing information about volumetric density and microarchitecture, but interpretation is challenging because of the complex interactions between the numerous properties measured. In this study, we propose that there are common combinations of bone properties, referred to as phenotypes, that are predisposed to different levels of fracture risk. Using HR-pQCT data from a multinational cohort (n = 5873, 71% female) between 40 and 96 years of age, we employed fuzzy c-means clustering, an unsupervised machine-learning method, to identify phenotypes of bone microarchitecture. Three clusters were identified, and using partial correlation analysis of HR-pQCT parameters, we characterized the clusters as low density, low volume, and healthy bone phenotypes. Most males were associated with the healthy bone phenotype, whereas females were more often associated with the low volume or low density bone phenotypes. Each phenotype had a significantly different cumulative hazard of major osteoporotic fracture (MOF) and of any incident osteoporotic fracture (p < 0.05). After adjustment for covariates (cohort, sex, and age), the low density followed by the low volume phenotype had the highest association with MOF (hazard ratio = 2.96 and 2.35, respectively), and significant associations were maintained when additionally adjusted for femoral neck aBMD (hazard ratio = 1.69 and 1.90, respectively). Further, within each phenotype, different imaging biomarkers of fracture were identified. These findings suggest that osteoporotic fracture risk is associated with bone phenotypes that capture key features of bone deterioration that are not distinguishable by aBMD. © 2021 American Society for Bone and Mineral Research (ASBMR).  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