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   2566372篇
  免费   178966篇
  国内免费   5757篇
耳鼻咽喉   33922篇
儿科学   86307篇
妇产科学   71235篇
基础医学   364640篇
口腔科学   74318篇
临床医学   230257篇
内科学   494825篇
皮肤病学   58196篇
神经病学   198476篇
特种医学   99634篇
外国民族医学   606篇
外科学   386643篇
综合类   57709篇
现状与发展   4篇
一般理论   870篇
预防医学   196008篇
眼科学   60750篇
药学   186737篇
  11篇
中国医学   5882篇
肿瘤学   144065篇
  2018年   30219篇
  2017年   24092篇
  2016年   25636篇
  2015年   30050篇
  2014年   39571篇
  2013年   56520篇
  2012年   81039篇
  2011年   81249篇
  2010年   47808篇
  2009年   46143篇
  2008年   73914篇
  2007年   79154篇
  2006年   80027篇
  2005年   83819篇
  2004年   82991篇
  2003年   75663篇
  2002年   69124篇
  2001年   124300篇
  2000年   125962篇
  1999年   106949篇
  1998年   28273篇
  1997年   24833篇
  1996年   24891篇
  1995年   23926篇
  1994年   21998篇
  1993年   20400篇
  1992年   83874篇
  1991年   81650篇
  1990年   79391篇
  1989年   76489篇
  1988年   69666篇
  1987年   68595篇
  1986年   64611篇
  1985年   61426篇
  1984年   45236篇
  1983年   38305篇
  1982年   21702篇
  1981年   19327篇
  1979年   41079篇
  1978年   28652篇
  1977年   24331篇
  1976年   22599篇
  1975年   24357篇
  1974年   29637篇
  1973年   28323篇
  1972年   26389篇
  1971年   24572篇
  1970年   22857篇
  1969年   21498篇
  1968年   19981篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
12.
We report two British cases of liver abscess, due to Klebsiella pneumoniae and associated with synchronous infection elsewhere, which required liver resection for definitive treatment. They illustrate the geographic spread of aggressive K pneumoniae liver infection and demonstrate the importance of early aggressive treatment.  相似文献   
13.
14.
15.
Dosage form is a mean used for the delivery of drug to a living body. In order to get the desired effect the drug should be delivered to its site of action at such rate and concentration to achieve the maximum therapeutic effect and minimum adverse effect. Since oral route is still widely accepted route but having a common drawback of difficulty in swallowing of tablets and capsules. Therefore a lot of research has been done on novel drug delivery systems. This review is about oral dispersible tablets a novel approach in drug delivery systems that are now a day''s more focused in formulation world, and laid a new path that, helped the patients to build their compliance level with the therapy, also reduced the cost and ease the administration especially in case of pediatrics and geriatrics. Quick absorption, rapid onset of action and reduction in drug loss properties are the basic advantages of this dosage form.  相似文献   
16.
Sinus venosus atrial septal defect (SV‐ASD) usually coexists with partial anomalous pulmonary vein connection (PAPVC). It is a difficult diagnosis in transthoracic echocardiography (TTE) due to eccentric position of defects. We present a rare case of atypical anatomical variation in PAPVC, which was never described before. Two right pulmonary veins drained into superior vena cava, which overrode SV‐ASD and interatrial septum, a third pulmonary vein into the right atrium. Complete diagnosis could not be set after TTE, nor transesophageal echocardiography, whereas angio‐CT was finally conclusive. This diagnostic approach allowed the surgical planning.  相似文献   
17.
18.
Hepatic NADPH-cytochrome P450 oxidoreductase null (HRN?) mice exhibit normal hepatic and extrahepatic biotransformation enzyme activities when compared to wild-type (WT) mice, but express no functional hepatic cytochrome P450 activities. When incubated in vitro with [14C]-diclofenac, liver microsomes from WT mice exhibited extensive biotransformation to oxidative and glucuronide metabolites and covalent binding to proteins was also observed. In contrast, whereas glucuronide conjugates and a quinone-imine metabolite were formed when [14C]-diclofenac was incubated with HRN? mouse liver, only small quantities of P450-derived oxidative metabolites were produced in these samples and covalent binding to proteins was not observed. Livers from vehicle-treated HRN? mice exhibited enhanced lipid accumulation, bile duct proliferation, hepatocellular degeneration and necrosis and inflammatory cell infiltration, which were not present in livers from WT mice. Elevated liver-derived alanine aminotransferase, glutamate dehydrogenase and alkaline phosphatase activities were also observed in plasma from HRN? mice. When treated orally with diclofenac for 7 days, at 30 mg/kg/day, the severities of the abnormal liver histopathology and plasma liver enzyme findings in HRN? mice were reduced markedly. Oral diclofenac administration did not alter the liver histopathology or elevate plasma enzyme activities of WT mice. These findings indicate that HRN? mice are valuable for exploration of the role played by hepatic P450s in drug biotransformation, but poorly suited to investigations of drug-induced liver toxicity. Nevertheless, studies in HRN? mice could provide novel insights into the role played by inflammation in liver injury and may aid the evaluation of new strategies for its treatment.  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