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   1874698篇
  免费   140264篇
  国内免费   2954篇
耳鼻咽喉   24074篇
儿科学   62006篇
妇产科学   51416篇
基础医学   257376篇
口腔科学   50972篇
临床医学   165264篇
内科学   364272篇
皮肤病学   36095篇
神经病学   155942篇
特种医学   77102篇
外国民族医学   478篇
外科学   287358篇
综合类   43487篇
现状与发展   3篇
一般理论   690篇
预防医学   149627篇
眼科学   41309篇
药学   137535篇
  3篇
中国医学   3730篇
肿瘤学   109177篇
  2018年   37495篇
  2017年   29482篇
  2016年   32839篇
  2015年   18255篇
  2014年   24915篇
  2013年   37106篇
  2012年   56616篇
  2011年   72122篇
  2010年   48161篇
  2009年   40089篇
  2008年   67926篇
  2007年   72606篇
  2006年   53794篇
  2005年   53653篇
  2004年   54040篇
  2003年   52407篇
  2002年   49574篇
  2001年   77486篇
  2000年   80040篇
  1999年   68041篇
  1998年   19335篇
  1997年   17598篇
  1996年   17277篇
  1995年   16952篇
  1994年   15925篇
  1993年   15011篇
  1992年   56399篇
  1991年   54757篇
  1990年   53480篇
  1989年   51634篇
  1988年   47960篇
  1987年   47304篇
  1986年   44976篇
  1985年   43602篇
  1984年   32699篇
  1983年   28142篇
  1982年   16689篇
  1981年   14895篇
  1979年   30861篇
  1978年   21454篇
  1977年   18083篇
  1976年   17010篇
  1975年   17809篇
  1974年   21790篇
  1973年   20932篇
  1972年   19103篇
  1971年   17981篇
  1970年   16487篇
  1969年   15481篇
  1968年   14153篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
72.
73.
74.
PURPOSE: In children with locally advanced or recurrent malignant tumours, prognosis can be improved by regional deep hyperthermia (RHT) in combination with platin-based chemotherapy. However, because of the increasing number of patients that achieve long-time remission with this therapy, it is necessary to evaluate long-term sequelae of thermochemotherapy. During the years 1993-2004 one has observed avascular osteonecrosis (AON) of the femoral head after RHT in seven children with pelvic germ cell tumours or rhabdomyosarcomas. METHODS: Although AON may develop in patients with malignancies treated with chemo- or radiotherapy alone, RHT might nevertheless contribute to the occurrence of AON. In order to determine potential risk factors for AON after RHT, this study analysed the relationship of AON to the patient's age, medical history and treatment parameters such as thermal dose equivalent and power output. RESULTS AND CONCLUSIONS: In the present study AON was associated with young age as well as intensity of hyperthermia indicated by high power levels that exceed 20 W per kg body weight and/or application of eight or more heat sessions as well as additional radiotherapy. Based on this observation, it was assumed that an optimized three dimensional thermal field modelling may be helpful to avoid hazardous temperatures in the femoral heads during RHT treatment and to reduce AON of the femoral heads.  相似文献   
75.
76.
Carbon monoxide (CO), a byproduct of heme catalysis, was shown to have potent cytoprotective and anti-inflammatory effects. In vivo recipient CO inhalation at low concentrations prevented ischemia/reperfusion (I/R) injury associated with small intestinal transplantation (SITx). This study examined whether ex vivo delivery of CO in University of Wisconsin (UW) solution could ameliorate intestinal I/R injury. Orthotopic syngenic SITx was performed in Lewis rats after 6 h cold preservation in control UW or UW that was bubbled with CO gas (0.1-5%) (CO-UW). Recipient survival with intestinal grafts preserved in 5%, but not 0.1%, CO-UW improved to 86.7% (13/15) from 53% (9/17) with control UW. At 3 h after SITx, grafts stored in 5% CO-UW showed improved intestinal barrier function, less mucosal denudation and reduced inflammatory mediator upregulation compared to those in control UW. Preservation in CO-UW associated with reduced vascular resistance (end preservation), increased graft cyclic guanosine monophosphate levels (1 h), and improved graft blood flow (1 h). Protective effects of CO-UW were reversed by ODQ, an inhibitor of soluble guanylyl cyclase. In vitro culture experiment also showed better preservation of vascular endothelial cells with CO-UW. The study suggests that ex vivo CO delivery into UW solution would be a simple and innovative therapeutic strategy to prevent transplant-induced I/R injury.  相似文献   
77.
The absence of the temporary incisors could be to a genetic illness or to some multiple premature extractions. These extractions are the aftermaths of the carious lesions or some traumatisms underwent by the temporary incisors. Beyond measure the loss of the space, the premature loss some temporary incisors very often assign the relational development of the child and disturb its psychological development and the aesthetic function. Across some cases clinics, the authors show that the replacement of the temporary incisors is the therapeutic ideal solution. Indeed, the child prosthesis, replacing the temporary absent incisors, solves the psychological, aesthetic and relational problems of the child.  相似文献   
78.
79.
背景:针对糖尿病患者Lp(a)水平和冠状动脉疾病(CAD)严重程度之间关系的研究较少并且结论有争议。另外,目前尚无关于apo(a)多态性与上述疾病关系的研究。本研究旨在探讨大样本2型糖尿病患者中冠状动脉粥样硬化的程度与Lp(a)水平及apo(a)多态性的相关性。方法:连续选取227例2型糖  相似文献   
80.
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