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   1380276篇
  免费   100587篇
  国内免费   5600篇
耳鼻咽喉   18567篇
儿科学   42030篇
妇产科学   38058篇
基础医学   199802篇
口腔科学   39782篇
临床医学   121252篇
内科学   271859篇
皮肤病学   31969篇
神经病学   106877篇
特种医学   53365篇
外国民族医学   378篇
外科学   210000篇
综合类   32580篇
现状与发展   2篇
一般理论   462篇
预防医学   95381篇
眼科学   32164篇
药学   104070篇
  4篇
中国医学   4578篇
肿瘤学   83283篇
  2021年   11077篇
  2019年   10840篇
  2018年   15857篇
  2017年   12166篇
  2016年   13957篇
  2015年   16332篇
  2014年   22040篇
  2013年   31430篇
  2012年   42380篇
  2011年   43902篇
  2010年   26323篇
  2009年   24577篇
  2008年   39988篇
  2007年   42170篇
  2006年   42031篇
  2005年   39860篇
  2004年   38335篇
  2003年   36720篇
  2002年   35206篇
  2001年   72335篇
  2000年   73987篇
  1999年   61616篇
  1998年   16045篇
  1997年   13990篇
  1996年   13689篇
  1995年   12939篇
  1994年   11947篇
  1993年   11049篇
  1992年   46976篇
  1991年   45137篇
  1990年   44091篇
  1989年   42907篇
  1988年   38877篇
  1987年   38551篇
  1986年   35734篇
  1985年   34231篇
  1984年   24849篇
  1983年   20707篇
  1982年   11759篇
  1979年   22016篇
  1978年   15374篇
  1977年   13091篇
  1976年   11871篇
  1975年   12675篇
  1974年   15213篇
  1973年   14549篇
  1972年   13560篇
  1971年   12745篇
  1970年   11782篇
  1969年   11150篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
1.
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.

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   
5.
Social Psychiatry and Psychiatric Epidemiology - The negative effect of catastrophic financial loss on suicide risk is widely perceived but hardly studied in-depth because of various difficulties...  相似文献   
6.
7.
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