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   4357293篇
  免费   352959篇
  国内免费   15493篇
耳鼻咽喉   62018篇
儿科学   135178篇
妇产科学   113477篇
基础医学   664448篇
口腔科学   120461篇
临床医学   395296篇
内科学   790612篇
皮肤病学   104491篇
神经病学   373925篇
特种医学   172958篇
外国民族医学   921篇
外科学   662254篇
综合类   127273篇
现状与发展   24篇
一般理论   2692篇
预防医学   368473篇
眼科学   102864篇
药学   307083篇
  24篇
中国医学   11459篇
肿瘤学   209814篇
  2021年   56290篇
  2020年   35863篇
  2019年   59052篇
  2018年   73962篇
  2017年   56507篇
  2016年   62997篇
  2015年   76228篇
  2014年   111141篇
  2013年   176932篇
  2012年   123705篇
  2011年   127683篇
  2010年   125080篇
  2009年   127661篇
  2008年   114606篇
  2007年   122029篇
  2006年   130920篇
  2005年   126317篇
  2004年   127153篇
  2003年   117575篇
  2002年   108001篇
  2001年   154603篇
  2000年   150698篇
  1999年   139805篇
  1998年   71674篇
  1997年   68039篇
  1996年   65859篇
  1995年   61672篇
  1994年   55771篇
  1993年   51767篇
  1992年   103716篇
  1991年   99073篇
  1990年   94169篇
  1989年   91806篇
  1988年   85418篇
  1987年   83874篇
  1986年   79556篇
  1985年   78035篇
  1984年   66079篇
  1983年   58977篇
  1982年   48290篇
  1981年   45012篇
  1980年   42290篇
  1979年   57923篇
  1978年   47122篇
  1977年   41670篇
  1976年   38732篇
  1975年   37909篇
  1974年   42505篇
  1973年   40619篇
  1972年   38067篇
排序方式: 共有10000条查询结果,搜索用时 0 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