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   954696篇
  免费   68086篇
  国内免费   1392篇
耳鼻咽喉   13136篇
儿科学   25226篇
妇产科学   23911篇
基础医学   135798篇
口腔科学   28493篇
临床医学   84532篇
内科学   187163篇
皮肤病学   19541篇
神经病学   74439篇
特种医学   37176篇
外国民族医学   79篇
外科学   154010篇
综合类   18399篇
现状与发展   1篇
一般理论   281篇
预防医学   65159篇
眼科学   21536篇
药学   73828篇
  3篇
中国医学   2179篇
肿瘤学   59284篇
  2018年   9462篇
  2017年   7382篇
  2016年   8178篇
  2015年   9307篇
  2014年   12603篇
  2013年   18550篇
  2012年   25582篇
  2011年   26542篇
  2010年   15631篇
  2009年   15087篇
  2008年   26125篇
  2007年   27350篇
  2006年   27988篇
  2005年   26914篇
  2004年   26053篇
  2003年   24923篇
  2002年   24482篇
  2001年   54931篇
  2000年   56713篇
  1999年   47163篇
  1998年   11064篇
  1997年   9730篇
  1996年   9827篇
  1995年   9135篇
  1994年   8490篇
  1993年   7780篇
  1992年   35620篇
  1991年   34006篇
  1990年   32858篇
  1989年   31967篇
  1988年   29109篇
  1987年   28341篇
  1986年   26388篇
  1985年   25254篇
  1984年   17955篇
  1983年   15247篇
  1982年   7970篇
  1981年   6901篇
  1979年   15848篇
  1978年   10679篇
  1977年   9113篇
  1976年   7947篇
  1975年   8700篇
  1974年   10547篇
  1973年   9950篇
  1972年   9405篇
  1971年   8899篇
  1970年   8463篇
  1969年   7951篇
  1968年   7216篇
排序方式: 共有10000条查询结果,搜索用时 328 毫秒
31.
32.
33.
34.
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   
35.
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   
36.
37.
芦荟自古就被用作化妆品和药物添加剂,近来更受喜爱。虽应用广泛,但过敏反应罕有报道。作者用芦荟叶的油性提取物、来自整个植株的芦荟粉及浓缩的芦荟凝胶,对相继就诊的702例患者做斑贴试验。设计专门的问卷调查芦荟的使用、使用原因、使用部位、不良反应、患者职业、个人爱好及是否为遗传性过敏体质。患者均未对任一制剂发生任何反应。需对芦荟所含的两种成分加以鉴别:即芦荟叶皮含有的具有促进肠蠕动、潜在抗菌及抗癌特性的蒽醌类物质。  相似文献   
38.
39.
Published data devoted to making and characterization of the properties of polymeric wound dressings with proteolytic action are reviewed. These data are indicative of individual dependence of the physicochemical properties, activity, and stability of each particular enzyme on the type of polymer matrix and the method of immobilization. In order to obtain wound dressings, which are active in physiological medium and retain their activity upon sterilization, it is necessary to optimize the composition and characteristics of a polymer matrix and the enzyme included into its structure. __________ Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 40, No. 8, pp. 24–28, August, 2006.  相似文献   
40.
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