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   3241581篇
  免费   269611篇
  国内免费   13729篇
耳鼻咽喉   44270篇
儿科学   103979篇
妇产科学   83014篇
基础医学   522141篇
口腔科学   87019篇
临床医学   291825篇
内科学   564873篇
皮肤病学   88338篇
神经病学   279095篇
特种医学   127431篇
外国民族医学   329篇
外科学   501442篇
综合类   100704篇
现状与发展   23篇
一般理论   2265篇
预防医学   274624篇
眼科学   73865篇
药学   220512篇
  23篇
中国医学   9313篇
肿瘤学   149836篇
  2021年   54820篇
  2020年   35008篇
  2019年   57935篇
  2018年   70759篇
  2017年   54000篇
  2016年   59570篇
  2015年   73717篇
  2014年   107881篇
  2013年   173131篇
  2012年   86755篇
  2011年   86303篇
  2010年   115314篇
  2009年   120021篇
  2008年   73384篇
  2007年   75551篇
  2006年   86698篇
  2005年   81973篇
  2004年   84291篇
  2003年   75351篇
  2002年   65063篇
  2001年   94483篇
  2000年   87031篇
  1999年   88724篇
  1998年   64335篇
  1997年   62375篇
  1996年   60141篇
  1995年   55674篇
  1994年   49954篇
  1993年   46518篇
  1992年   62408篇
  1991年   59527篇
  1990年   56624篇
  1989年   56017篇
  1988年   51655篇
  1987年   51074篇
  1986年   48180篇
  1985年   48698篇
  1984年   45303篇
  1983年   41573篇
  1982年   40693篇
  1981年   38511篇
  1980年   36213篇
  1979年   37099篇
  1978年   33772篇
  1977年   30976篇
  1976年   28481篇
  1975年   26816篇
  1974年   27605篇
  1973年   26548篇
  1972年   24665篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Quality of Life Research - The COVID-19 pandemic might add to the stressors experienced by people living with rheumatic diseases. This study aimed to examine rheumatic patients’ functional...  相似文献   
2.
Molnár  B.  Aroca  S.  Dobos  A.  Orbán  K.  Szabó  J.  Windisch  P.  Stähli  A.  Sculean  A. 《Clinical oral investigations》2022,26(12):7135-7142
Clinical Oral Investigations - To evaluate t he long-term outcomes following treatment of RT 1 multiple adjacent gingival recessions (MAGR) using the modified coronally advanced tunnel (MCAT) with...  相似文献   
3.

Physical activity brings significant health benefits to middle-aged adults, although the research to date has been focused on late adulthood. This study aims to examine how ageing affects the self-reported and accelerometer-derived measures of physical activity levels in middle-aged adults. We employed the data recorded in the UK Biobank and analysed the physical activity levels of 2,998 participants (1381 men and 1617 women), based on self-completion questionnaire and accelerometry measurement of physical activity. We also assessed the musculoskeletal health of the participants using the dual-energy X-ray absorptiometry (DXA) measurements provided by the UK Biobank. Participants were categorised into three groups according to their age: group I younger middle-aged (40 to 49 years), group II older middle-aged (50 to 59 years), and group III oldest middle-aged (60 to 69 years). Self-reported physical activity level increased with age and was the highest in group III, followed by group II and I (P?<?0.05). On the contrary, physical activity measured by accelerometry decreased significantly with age from group I to III (P?<?0.05), and the same pertained to the measurements of musculoskeletal health (P?<?0.05). It was also shown that middle-aged adults mostly engaged in low and moderate intensity activities. The opposing trends of the self-reported and measured physical activity levels may suggest that middle-aged adults over-report their activity level as they age. They should be aware of the difference between their perceived and actual physical activity levels, and objective measures would be useful to prevent the decline in musculoskeletal health.

  相似文献   
4.
5.

Interstitial lung disease (ILD) represents a significant cause of morbidity and mortality in systemic sclerosis (SSc). The purpose of this study was to examine recirculating lymphocytes from SSc patients for potential biomarkers of interstitial lung disease (ILD). Peripheral blood mononuclear cells (PBMCs) were isolated from patients with SSc and healthy controls enrolled in the Vanderbilt University Myositis and Scleroderma Treatment Initiative Center cohort between 9/2017–6/2019. Clinical phenotyping was performed by chart abstraction. Immunophenotyping was performed using both mass cytometry and fluorescence cytometry combined with t-distributed stochastic neighbor embedding analysis and traditional biaxial gating. This study included 34 patients with SSc-ILD, 14 patients without SSc-ILD, and 25 healthy controls. CD21lo/neg cells are significantly increased in SSc-ILD but not in SSc without ILD (15.4 ± 13.3% vs. 5.8 ± 0.9%, p = 0.002) or healthy controls (5.0 ± 0.5%, p < 0.0001). While CD21lo/neg B cells can be identified from a single biaxial gate, tSNE analysis reveals that the biaxial gate is comprised of multiple distinct subsets, all of which are increased in SSc-ILD. CD21lo/neg cells in both healthy controls and SSc-ILD are predominantly tBET positive and do not have intracellular CD21. Immunohistochemistry staining demonstrated that CD21lo/neg B cells diffusely infiltrate the lung parenchyma of an SSc-ILD patient. Additional work is needed to validate this biomarker in larger cohorts and longitudinal studies and to understand the role of these cells in SSc-ILD.

  相似文献   
6.
7.
Journal of Medical Ultrasonics - Chronic liver disease is still a major problem because disease progression will ultimately lead to liver cirrhosis. Portal hypertension is the hallmark in advanced...  相似文献   
8.
9.
10.
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