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   4861275篇
  免费   365446篇
  国内免费   15371篇
耳鼻咽喉   67751篇
儿科学   155289篇
妇产科学   128457篇
基础医学   730785篇
口腔科学   133875篇
临床医学   445878篇
内科学   881337篇
皮肤病学   118305篇
神经病学   403765篇
特种医学   189126篇
外国民族医学   935篇
外科学   727015篇
综合类   134257篇
现状与发展   24篇
一般理论   2765篇
预防医学   399391篇
眼科学   114763篇
药学   349433篇
  29篇
中国医学   13280篇
肿瘤学   245632篇
  2021年   56883篇
  2019年   59264篇
  2018年   75948篇
  2017年   58352篇
  2016年   64721篇
  2015年   77224篇
  2014年   111598篇
  2013年   177369篇
  2012年   138443篇
  2011年   145750篇
  2010年   130483篇
  2009年   130677篇
  2008年   131113篇
  2007年   140520篇
  2006年   148304篇
  2005年   142198篇
  2004年   142880篇
  2003年   132743篇
  2002年   121686篇
  2001年   194970篇
  2000年   191409篇
  1999年   172351篇
  1998年   75031篇
  1997年   69868篇
  1996年   67957篇
  1995年   63410篇
  1994年   57176篇
  1993年   52997篇
  1992年   125425篇
  1991年   119954篇
  1990年   115788篇
  1989年   112794篇
  1988年   103580篇
  1987年   101185篇
  1986年   95626篇
  1985年   92834篇
  1984年   75542篇
  1983年   66383篇
  1982年   50572篇
  1981年   46653篇
  1980年   43796篇
  1979年   65148篇
  1978年   50880篇
  1977年   45560篇
  1976年   41710篇
  1975年   42721篇
  1974年   46891篇
  1973年   44921篇
  1972年   42233篇
  1971年   39141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