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   4346125篇
  免费   336481篇
  国内免费   13947篇
耳鼻咽喉   60810篇
儿科学   139459篇
妇产科学   114403篇
基础医学   666584篇
口腔科学   117335篇
临床医学   392893篇
内科学   784770篇
皮肤病学   108534篇
神经病学   358756篇
特种医学   168915篇
外国民族医学   539篇
外科学   666962篇
综合类   122703篇
现状与发展   23篇
一般理论   2646篇
预防医学   362231篇
眼科学   102266篇
药学   303362篇
  26篇
中国医学   11582篇
肿瘤学   211754篇
  2021年   55877篇
  2020年   35579篇
  2019年   58538篇
  2018年   74151篇
  2017年   56630篇
  2016年   62764篇
  2015年   75640篇
  2014年   110098篇
  2013年   175335篇
  2012年   124077篇
  2011年   130120篇
  2010年   126516篇
  2009年   127438篇
  2008年   116435篇
  2007年   124395篇
  2006年   132823篇
  2005年   127876篇
  2004年   128166篇
  2003年   118456篇
  2002年   107705篇
  2001年   156256篇
  2000年   151273篇
  1999年   139866篇
  1998年   70750篇
  1997年   66630篇
  1996年   64907篇
  1995年   60096篇
  1994年   54254篇
  1993年   50423篇
  1992年   100245篇
  1991年   96976篇
  1990年   93383篇
  1989年   91079篇
  1988年   83917篇
  1987年   82414篇
  1986年   77593篇
  1985年   76520篇
  1984年   64022篇
  1983年   57389篇
  1982年   46827篇
  1981年   43767篇
  1980年   41113篇
  1979年   55583篇
  1978年   45583篇
  1977年   40172篇
  1976年   37498篇
  1975年   37822篇
  1974年   41363篇
  1973年   39624篇
  1972年   37180篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
82.
83.
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   
84.
85.
86.
87.
88.
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   
89.
90.
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   
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