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   3237846篇
  免费   232195篇
  国内免费   6589篇
耳鼻咽喉   44800篇
儿科学   105949篇
妇产科学   88480篇
基础医学   473446篇
口腔科学   90217篇
临床医学   293005篇
内科学   619371篇
皮肤病学   73072篇
神经病学   254432篇
特种医学   126501篇
外国民族医学   841篇
外科学   483566篇
综合类   67281篇
现状与发展   17篇
一般理论   1230篇
预防医学   253702篇
眼科学   76052篇
药学   241421篇
  12篇
中国医学   7435篇
肿瘤学   175800篇
  2021年   27457篇
  2019年   27059篇
  2018年   39740篇
  2017年   31059篇
  2016年   34498篇
  2015年   40707篇
  2014年   54289篇
  2013年   77888篇
  2012年   110973篇
  2011年   112627篇
  2010年   66807篇
  2009年   63606篇
  2008年   101949篇
  2007年   108339篇
  2006年   108808篇
  2005年   111839篇
  2004年   108663篇
  2003年   100653篇
  2002年   93355篇
  2001年   140207篇
  2000年   142459篇
  1999年   121610篇
  1998年   35356篇
  1997年   31019篇
  1996年   31208篇
  1995年   29657篇
  1994年   27324篇
  1993年   25699篇
  1992年   95674篇
  1991年   93800篇
  1990年   91765篇
  1989年   88411篇
  1988年   81321篇
  1987年   80106篇
  1986年   75162篇
  1985年   72011篇
  1984年   53692篇
  1983年   45546篇
  1982年   26925篇
  1979年   49897篇
  1978年   35611篇
  1977年   29736篇
  1976年   28332篇
  1975年   30636篇
  1974年   37043篇
  1973年   35188篇
  1972年   33020篇
  1971年   31253篇
  1970年   28836篇
  1969年   27371篇
排序方式: 共有10000条查询结果,搜索用时 31 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.

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.
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