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   21618篇
  免费   1262篇
  国内免费   187篇
耳鼻咽喉   149篇
儿科学   1250篇
妇产科学   324篇
基础医学   2666篇
口腔科学   363篇
临床医学   1329篇
内科学   3703篇
皮肤病学   412篇
神经病学   1399篇
特种医学   724篇
外国民族医学   5篇
外科学   3003篇
综合类   817篇
一般理论   1篇
预防医学   1476篇
眼科学   1125篇
药学   2201篇
  5篇
中国医学   317篇
肿瘤学   1798篇
  2022年   248篇
  2021年   461篇
  2020年   296篇
  2019年   328篇
  2018年   401篇
  2017年   315篇
  2016年   395篇
  2015年   448篇
  2014年   629篇
  2013年   855篇
  2012年   1229篇
  2011年   1231篇
  2010年   747篇
  2009年   605篇
  2008年   1053篇
  2007年   1034篇
  2006年   971篇
  2005年   939篇
  2004年   834篇
  2003年   840篇
  2002年   777篇
  2001年   630篇
  2000年   654篇
  1999年   588篇
  1998年   256篇
  1997年   230篇
  1996年   206篇
  1995年   191篇
  1994年   149篇
  1993年   160篇
  1992年   372篇
  1991年   397篇
  1990年   356篇
  1989年   400篇
  1988年   303篇
  1987年   308篇
  1986年   251篇
  1985年   270篇
  1984年   235篇
  1983年   207篇
  1982年   130篇
  1981年   121篇
  1979年   189篇
  1978年   127篇
  1976年   111篇
  1975年   135篇
  1974年   143篇
  1973年   137篇
  1972年   125篇
  1971年   143篇
排序方式: 共有10000条查询结果,搜索用时 62 毫秒
61.
采用紫外分光光度法测定长春丁汀片的含量。长春西汀片在274mm波长处有最大吸收,方法线性范围是10-20μg/ml,回归方程Y=30.092X+0.0533,r=0.9999,平均回收率为101.38%(n=5,RSD=0.71%)。  相似文献   
62.
63.
The present study was undertaken to determine the effect of two different types of liver cell proliferative stimuli, namely compensatory regeneration and direct hyperplasia on DNA synthesis of normal and preneoplastic isolated hepatocytes. Platelet-poor plasma (PPP) isolated from male Wistar rats treated with three different hepato-mitogens, lead nitrate (LN), cyproterone acetate (CPA) and ethylene dibromide (EDB), or subjected to surgical partial hepatectomy (PH), was tested for its ability to stimulate DNA synthesis in normal and preneoplastic hepatocytes in primary cultures. Induction of DNA synthesis was detected as early as 30 min after CPA, EDB and PH administration and persisted up to 5 days after the LN administration. In addition, hepatocytes isolated from preneoplastic liver nodules were also able to respond in culture to the DNA synthesis stimulus induced by these factors.  相似文献   
64.
The introduction of different types of pollutants like those from industrial effluence, bye-products from petro-chemical industries, pesticidal application, wastages of nuclear power industries, etc. is viewed seriously by the society. For the control of vectors of disease the adoption of environmental management is, therefore, imperative. The physical methods like drainage of excess and waste water, making water unsuitable for vector breeding by adopting various indigenous methods in vogue, the intra and inter-sectrol coordination and community based activities are identified as the basic approaches for achieving this goal. Minimising the potentiality of vector breeding through source reduction and water management is thought to be the simplest, cheapest and most permanent method. For the society having varying types of habitation and varying degree of habitational facilities like planned housing, water supply and disposal, sanitation and organized anti-vector measures, the adoption of environmental management to exercise check over vector population is a promising proposition. The suitability of such an approach has already been demonstrated by MRC, (ICMR), Delhi and V.C.R.C., Pondicherry. The implementation of these methods is to be initiated right from Primary Health Centre and district level onwards and community is to be motivated to the extent that the various methods of environmental management for vector control are adopted in the routine way of life. In the present article these ideas have been touched upon and various methods of environmental management described in brief. In addition what other Governmental agencies are required to do in order to effectively implement environmental management methods are briefly enlisted.  相似文献   
65.
A 36-year-old man was brought to the emergency department after being assaulted. A mandible series showed a nondisplaced fracture through the angle of the mandible extending through the left third molar tooth. Axial slices from a nonhelical computed tomographic (CT) examination of the head as well as a helical CT examination of the mandible failed to demonstrate the fracture. The fracture was well shown, however, on sagittal CT reformations. Although CT is generally regarded as more sensitive than plain radiography for the detection of fractures, fractures may be overlooked by CT if examination in only one plane is performed.  相似文献   
66.
67.
The present study was undertaken to evaluate the noise attenuation characteristics of different types of Ear protective Devices which are commonly used. 20 healthy normal subjects’ open and closed hearing thresholds (with the usage of ear protective device) were recorded in an anechoic chamber and the attenuation charactaristics at 8 discrete frequencies were analysed and compared. Though the attenuation given by different types of ear protective devices are variable and not the ideal, still the present generation of devices have shown satisfactory attenuation characteristics, It is important that proper selection, fitment and usage of these devices should he carefully thought of prior to its usage.  相似文献   
68.
By a double-labeling method combining the retrograde tracing of horseradish peroxidase and the immunocytochemical technique, serotonin-like immunoreactive neurons in the midbrain periaqueductal gray (PAG) and nucleus raphe dorsalis (DR) of the rat were observed to send projection fibers to the nucleus parafascicularis of the thalamus bilaterally with an ipsilateral dominance. These serotonin-containing projecting neurons were observed mainly at the middle-caudal levels of the ventrolateral subdivision of the PAG and less at the middle-rostral levels of the DR.  相似文献   
69.
军队高等医学院校课程教学质量评估的意义及作用:具有判断教育活动、获取信息、反馈、激励、促进教学改革六项功能.  相似文献   
70.
This article reviews a focused helical appendiceal computed tomographic technique and discusses an approach to appendiceal computed tomographic interpretation.  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