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   4357103篇
  免费   352963篇
  国内免费   15493篇
耳鼻咽喉   62015篇
儿科学   135171篇
妇产科学   113478篇
基础医学   664425篇
口腔科学   120466篇
临床医学   395255篇
内科学   790579篇
皮肤病学   104491篇
神经病学   373891篇
特种医学   172956篇
外国民族医学   921篇
外科学   662223篇
综合类   127272篇
现状与发展   24篇
一般理论   2692篇
预防医学   368461篇
眼科学   102864篇
药学   307078篇
  24篇
中国医学   11459篇
肿瘤学   209814篇
  2021年   56289篇
  2020年   35863篇
  2019年   59053篇
  2018年   73961篇
  2017年   56506篇
  2016年   62994篇
  2015年   76229篇
  2014年   111140篇
  2013年   176928篇
  2012年   123690篇
  2011年   127672篇
  2010年   125078篇
  2009年   127659篇
  2008年   114595篇
  2007年   122015篇
  2006年   130907篇
  2005年   126297篇
  2004年   127139篇
  2003年   117556篇
  2002年   107982篇
  2001年   154596篇
  2000年   150690篇
  1999年   139801篇
  1998年   71674篇
  1997年   68039篇
  1996年   65858篇
  1995年   61672篇
  1994年   55771篇
  1993年   51767篇
  1992年   103712篇
  1991年   99067篇
  1990年   94164篇
  1989年   91804篇
  1988年   85416篇
  1987年   83873篇
  1986年   79555篇
  1985年   78031篇
  1984年   66074篇
  1983年   58974篇
  1982年   48290篇
  1981年   45013篇
  1980年   42290篇
  1979年   57919篇
  1978年   47122篇
  1977年   41665篇
  1976年   38731篇
  1975年   37906篇
  1974年   42503篇
  1973年   40614篇
  1972年   38065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