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   2403894篇
  免费   180274篇
  国内免费   7147篇
耳鼻咽喉   32569篇
儿科学   76611篇
妇产科学   63266篇
基础医学   352833篇
口腔科学   64765篇
临床医学   219411篇
内科学   463189篇
皮肤病学   52472篇
神经病学   186926篇
特种医学   89826篇
外国民族医学   507篇
外科学   358547篇
综合类   61758篇
现状与发展   32篇
一般理论   849篇
预防医学   188278篇
眼科学   55401篇
药学   182108篇
  95篇
中国医学   9199篇
肿瘤学   132673篇
  2021年   20905篇
  2019年   20856篇
  2018年   28351篇
  2017年   21989篇
  2016年   24075篇
  2015年   28016篇
  2014年   39185篇
  2013年   57243篇
  2012年   79758篇
  2011年   84830篇
  2010年   51643篇
  2009年   48782篇
  2008年   78994篇
  2007年   83860篇
  2006年   84407篇
  2005年   81324篇
  2004年   76958篇
  2003年   73988篇
  2002年   71239篇
  2001年   110178篇
  2000年   112585篇
  1999年   94324篇
  1998年   27482篇
  1997年   24162篇
  1996年   24402篇
  1995年   23006篇
  1994年   21190篇
  1993年   19877篇
  1992年   72131篇
  1991年   70173篇
  1990年   68483篇
  1989年   65718篇
  1988年   60352篇
  1987年   59174篇
  1986年   55250篇
  1985年   53027篇
  1984年   39317篇
  1983年   33401篇
  1982年   19863篇
  1979年   35867篇
  1978年   25653篇
  1977年   21231篇
  1976年   20333篇
  1975年   21816篇
  1974年   26152篇
  1973年   24802篇
  1972年   23201篇
  1971年   22038篇
  1970年   20249篇
  1969年   19315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.
4.
5.
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   
6.
7.
8.
Noninvasive imaging of cardiac fibrosis is important for early diagnosis and intervention in chronic heart diseases. Here, we investigated whether noninvasive, contrast agent-free MRI T2-mapping can quantify myocardial fibrosis in preclinical models of aging and pressure overload. Myocardial fibrosis and remodeling were analyzed in two animal models: (i) aging (15-month-old male CF-1 mice vs. young 6- to 8-week-old mice), and (ii) pressure overload (PO; by transverse aortic constriction in 4- to 5-month-old male C57BL/6 mice vs. sham-operated for 14 days). In vivo T2-mapping was performed by acquiring data during the isovolumic and early diastolic phases, with a modified respiratory and ECG-triggered multiecho TurboRARE sequence on a 7-T MRI. Cine MRI provided cardiac morphology and function. A quantitative segmentation method was developed to analyze the in vivo T2-maps of hearts at midventricle, apex, and basal regions. The cardiac fibrosis area was analyzed ex vivo by picro sirius red (PSR) staining. Both aged and pressure-overloaded hearts developed significant myocardial contractile dysfunction, cardiac hypertrophy, and interstitial fibrosis. The aged mice had two phenotypes, fibrotic and mild-fibrotic. Notably, the aged fibrotic subgroup and the PO mice showed a marked decrease in T2 relaxation times (25.3 ± 0.6 in aged vs. 29.9 ± 0.7 ms in young mice, p = 0.002; and 24.3 ± 1.7 in PO vs. 28.7 ± 0.7 ms in shams, p = 0.05). However, no significant difference in T2 was detected between the aged mild-fibrotic subgroup and the young mice. Accordingly, an inverse correlation between myocardial fibrosis percentage (FP) and T2 relaxation time was derived (R2 = 0.98): T2 (ms) = 30.45 – 1.05 × FP. Thus, these results demonstrate a statistical agreement between T2-map–quantified fibrosis and PSR staining in two different clinically relevant animal models. In conclusion, T2-mapping MRI is a promising noninvasive contrast agent-free quantitative technique to characterize myocardial fibrosis.  相似文献   
9.
10.
The coronavirus disease 2019 (COVID-19) pandemic has rapidly created widespread impacts on global health and the economy. Data suggest that women are less susceptible to severe illness. However, sex-disaggregated data are incomplete, leaving room for misinterpretation, and focusing only on biologic sex underestimates the gendered impact of the pandemic on women. This narrative review summarizes what is known about gender disparities during the COVID-19 pandemic and the economic, domestic, and health burdens along with overlapping vulnerabilities related to the pandemic. In addition, this review outlines recommended strategies that advocacy groups, community leaders, and policymakers should implement to mitigate the widening gender disparities related to COVID-19.  相似文献   
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