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   3209131篇
  免费   232405篇
  国内免费   7126篇
耳鼻咽喉   43839篇
儿科学   104395篇
妇产科学   86941篇
基础医学   469930篇
口腔科学   89502篇
临床医学   299315篇
内科学   613804篇
皮肤病学   68628篇
神经病学   258192篇
特种医学   118298篇
外国民族医学   810篇
外科学   470420篇
综合类   69729篇
现状与发展   13篇
一般理论   1224篇
预防医学   261555篇
眼科学   74142篇
药学   238255篇
  16篇
中国医学   6826篇
肿瘤学   172828篇
  2021年   25802篇
  2019年   26710篇
  2018年   37039篇
  2017年   27935篇
  2016年   30916篇
  2015年   35076篇
  2014年   49127篇
  2013年   74968篇
  2012年   102805篇
  2011年   109548篇
  2010年   64792篇
  2009年   60569篇
  2008年   101939篇
  2007年   108403篇
  2006年   109257篇
  2005年   105785篇
  2004年   101016篇
  2003年   96901篇
  2002年   93706篇
  2001年   142440篇
  2000年   146403篇
  1999年   123256篇
  1998年   36550篇
  1997年   32163篇
  1996年   32169篇
  1995年   30427篇
  1994年   28252篇
  1993年   26575篇
  1992年   96762篇
  1991年   94937篇
  1990年   92381篇
  1989年   88559篇
  1988年   81718篇
  1987年   80151篇
  1986年   75681篇
  1985年   72542篇
  1984年   54223篇
  1983年   46343篇
  1982年   27756篇
  1979年   49984篇
  1978年   35720篇
  1977年   29573篇
  1976年   28577篇
  1975年   30253篇
  1974年   36534篇
  1973年   35208篇
  1972年   32854篇
  1971年   30979篇
  1970年   28700篇
  1969年   26906篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
12.
Bone mineral density (BMD) is a highly heritable predictor of osteoporotic fracture. GWAS have identified hundreds of loci influencing BMD, but few have been functionally analyzed. In this study, we show that SNPs within a BMD locus on chromosome 14q32.32 alter splicing and expression of PAR-1a/microtubule affinity regulating kinase 3 (MARK3), a conserved serine/threonine kinase known to regulate bioenergetics, cell division, and polarity. Mice lacking Mark3 either globally or selectively in osteoblasts have increased bone mass at maturity. RNA profiling from Mark3-deficient osteoblasts suggested changes in the expression of components of the Notch signaling pathway. Mark3-deficient osteoblasts exhibited greater matrix mineralization compared with controls that was accompanied by reduced Jag1/Hes1 expression and diminished downstream JNK signaling. Overexpression of Jag1 in Mark3-deficient osteoblasts both in vitro and in vivo normalized mineralization capacity and bone mass, respectively. Together, these findings reveal a mechanism whereby genetically regulated alterations in Mark3 expression perturb cell signaling in osteoblasts to influence bone mass.  相似文献   
13.
14.
15.
16.
The coronavirus 2019 pandemic has affected almost every aspect of health care delivery in the United States, and the emergency medicine system has been hit particularly hard while dealing with this public health crisis. In an unprecedented time in our history, medical systems and clinicians have been asked to be creative, flexible, and innovative, all while continuing to uphold the important standards in the US health care system. To continue providing quality services to patients during this extraordinary time, care providers, organizations, administrators, and insurers have needed to alter longstanding models and procedures to respond to the dynamics of a pandemic. The Emergency Medicine Treatment and Active Labor Act of 1986, or EMTALA, is 1 example of where these alterations have allowed health care facilities and clinicians to continue their work of caring for patients while protecting both the patients and the clinicians themselves from infectious exposures at the same time.  相似文献   
17.
18.
BackgroundTotal hip and knee arthroplasties are increasingly performed operations, and routine follow-up places huge demands on orthopedic services. This study investigates the effectiveness, patients’ satisfaction, and cost reduction of Virtual Joint Replacement Clinic (VJRC) follow-up of total hip arthroplasty and total knee arthroplasty patients in a university hospital. VJRC is especially valuable when in-person appointments are not advised or feasible such as during the COVID-19 pandemic.MethodsA total of 1749 patients who were invited for VJRC follow-up for knee or hip arthroplasty from January 2017 to December 2018 were included in this retrospective study. Patients were referred to VJRC after their 6-week postoperative review. Routine VJRC postoperative review was undertaken at 1 and 7 years and then 3-yearly thereafter. We evaluated the VJRC patient response rate, acceptability, and outcome. Patient satisfaction was measured in a subgroup of patients using a satisfaction survey. VJRC costs were calculated compared to face-to-face follow-up.ResultsThe VJRC had a 92.05% overall response rate. Only 7.22% required further in-person appointments with only 3% being reviewed by an orthopedic consultant. VJRC resulted in an estimated saving of £42,644 per year at our institution. The patients’ satisfaction survey showed that 89.29% of the patients were either satisfied or very satisfied with VJRC follow-up.ConclusionVJRC follow-up for hip and knee arthroplasty patients is an effective alternative to in-person clinic assessment which is accepted by patients, has high patient satisfaction, and can reduce the cost to both health services and patients.  相似文献   
19.
20.
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