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   7413篇
  免费   486篇
  国内免费   20篇
耳鼻咽喉   102篇
儿科学   238篇
妇产科学   104篇
基础医学   1230篇
口腔科学   199篇
临床医学   623篇
内科学   1633篇
皮肤病学   216篇
神经病学   584篇
特种医学   433篇
外国民族医学   2篇
外科学   1217篇
综合类   65篇
一般理论   1篇
预防医学   484篇
眼科学   92篇
药学   363篇
中国医学   3篇
肿瘤学   330篇
  2021年   113篇
  2020年   67篇
  2019年   85篇
  2018年   118篇
  2017年   83篇
  2016年   138篇
  2015年   144篇
  2014年   168篇
  2013年   234篇
  2012年   324篇
  2011年   375篇
  2010年   180篇
  2009年   195篇
  2008年   314篇
  2007年   366篇
  2006年   357篇
  2005年   277篇
  2004年   281篇
  2003年   312篇
  2002年   275篇
  2001年   239篇
  2000年   269篇
  1999年   216篇
  1998年   91篇
  1997年   83篇
  1996年   65篇
  1995年   58篇
  1994年   63篇
  1993年   53篇
  1992年   123篇
  1991年   118篇
  1990年   106篇
  1989年   109篇
  1988年   125篇
  1987年   139篇
  1986年   122篇
  1985年   120篇
  1984年   89篇
  1983年   68篇
  1982年   44篇
  1981年   50篇
  1979年   75篇
  1978年   64篇
  1976年   47篇
  1974年   61篇
  1973年   74篇
  1972年   53篇
  1971年   52篇
  1970年   49篇
  1968年   51篇
排序方式: 共有7919条查询结果,搜索用时 46 毫秒
1.
ResearchGate is a world wide web for scientists and researchers to share papers, ask and answer questions, and find collaborators. As one of the more than 15 million members, the author uploads research output and reads and responds to some of the questions raised, which are related to type 2 diabetes. In that way, he noticed a serious gap of knowledge of this disease among medical professionals over recent decades. The main aim of the current study is to remedy this situation through providing a comprehensive review on recent developments in biochemistry and molecular biology, which can be helpful for the scientific understanding of the molecular nature of type 2 diabetes. To fill up the shortcomings in the curricula of medical education, and to familiarize the medical community with a new concept of the onset of type 2 diabetes, items are discussed like: Insulin resistance, glucose effectiveness, insulin sensitivity, cell membranes, membrane flexibility, unsaturation index (UI; number of carbon-carbon double bonds per 100 acyl chains of membrane phospholipids), slow-down principle, effects of temperature acclimation on phospholipid membrane composition, free fatty acids, energy transport, onset of type 2 diabetes, metformin, and exercise. Based on the reviewed data, a new model is presented with proposed steps in the development of type 2 diabetes, a disease arising as a result of a hypothetical hereditary anomaly, which causes hyperthermia in and around the mitochondria. Hyperthermia is counterbalanced by the slow-down principle, which lowers the amount of carbon-carbon double bonds of membrane phospholipid acyl chains. The accompanying reduction in the UI lowers membrane flexibility, promotes a redistribution of the lateral pressure in cell membranes, and thereby reduces the glucose transporter protein pore diameter of the transmembrane glucose transport channel of all Class I GLUT proteins. These events will set up a reduction in transmembrane glucose transport. So, a new blood glucose regulation system, effective in type 2 diabetes and its prediabetic phase, is based on variations in the acyl composition of phospholipids and operates independent of changes in insulin and glucose concentration. UI assessment is currently arising as a promising analytical technology for a membrane flexibility analysis. An increase in mitochondrial heat production plays a pivotal role in the existence of this regulation system.  相似文献   
2.
3.
Oil-emulsified (OE) and aqueous (Aq) vaccines were prepared with the same batch of inactivated A24 8345 foot and mouth disease virus (FMDV). Calves born to vaccinated dams did not respond to the Aq vaccine 30 or 90 days post partum. When the OE vaccine was used on a similar group of calves, no responses were elicited up to 21 days post partum. However, calves 30 or more days old responded like adult cattle to the OE vaccine. When the OE vaccine was used in colostral antibody-free calves 3-30 days old, all animals showed good antibody responses but, in calves vaccinated 3 or 7 days post partum, antibodies were detectable only after a considerable period of time. Our results show that both passively acquired colostral antibodies and age are important in the response of very young calves to FMDV oil vaccines. From a practical point of view, in endemic areas where adult cattle are periodically vaccinated, vaccination of calves between 30 and 60 days post partum with OE vaccines would lead to high levels of herd protection.  相似文献   
4.
W C Hsiao  P Braun  E R Becker  S R Thomas 《JAMA》1987,258(6):799-802
This article describes the design and methods of a study currently under way to develop a Resource-Based Relative Value Scale (RBRVS); an alternative basis for establishing the payment rate for the services and procedures (S/Ps) of physicians in medical and surgical specialties. Physician resource inputs to be measured include (1) S/P time, (2) pre-S/P and post-S/P times, (3) intensity, (4) practice costs, including malpractice premiums, and (5) the cost of specialty training. These five factors will be combined to produce an RBRVS denominated in nonmonetary units. In the initial phase of the study, data on time and intensity will be obtained through a national survey of physicians who perform these S/Ps. In the second, consensus phase of the project, the investigators will convene a panel of representatives of the medical profession, third-party payers, consumers, and other interested parties to examine areas of agreement and disagreement as to how an RBRVS should be used for policy purposes. The final results of this study are expected by the summer of 1988.  相似文献   
5.
6.
International Journal of Legal Medicine -  相似文献   
7.
8.
9.
Long-term complications of renal transplantation   总被引:3,自引:0,他引:3  
  相似文献   
10.
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