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   4325582篇
  免费   351703篇
  国内免费   15387篇
耳鼻咽喉   61420篇
儿科学   134243篇
妇产科学   112659篇
基础医学   660276篇
口腔科学   119627篇
临床医学   392758篇
内科学   783429篇
皮肤病学   103876篇
神经病学   370923篇
特种医学   172091篇
外国民族医学   915篇
外科学   658826篇
综合类   126681篇
现状与发展   23篇
一般理论   2660篇
预防医学   366796篇
眼科学   101426篇
药学   304956篇
  24篇
中国医学   11416篇
肿瘤学   207647篇
  2021年   56062篇
  2020年   35747篇
  2019年   58988篇
  2018年   73836篇
  2017年   56371篇
  2016年   62741篇
  2015年   75986篇
  2014年   110836篇
  2013年   176461篇
  2012年   121640篇
  2011年   125190篇
  2010年   124391篇
  2009年   127113篇
  2008年   111866篇
  2007年   118918篇
  2006年   128200篇
  2005年   123106篇
  2004年   123956篇
  2003年   114323篇
  2002年   104792篇
  2001年   154496篇
  2000年   150589篇
  1999年   139705篇
  1998年   71455篇
  1997年   67874篇
  1996年   65732篇
  1995年   61593篇
  1994年   55645篇
  1993年   51678篇
  1992年   103627篇
  1991年   99005篇
  1990年   94092篇
  1989年   91727篇
  1988年   85348篇
  1987年   83823篇
  1986年   79497篇
  1985年   77960篇
  1984年   65980篇
  1983年   58885篇
  1982年   48173篇
  1981年   44902篇
  1980年   42192篇
  1979年   57839篇
  1978年   47046篇
  1977年   41607篇
  1976年   38658篇
  1975年   37854篇
  1974年   42430篇
  1973年   40568篇
  1972年   38026篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
71.
72.
73.
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   
74.
75.
76.
77.
78.
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   
79.
80.
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