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   2551303篇
  免费   200016篇
  国内免费   3979篇
耳鼻咽喉   36313篇
儿科学   86580篇
妇产科学   72154篇
基础医学   363011篇
口腔科学   72867篇
临床医学   226014篇
内科学   499208篇
皮肤病学   54920篇
神经病学   204589篇
特种医学   101881篇
外国民族医学   1064篇
外科学   388218篇
综合类   59939篇
现状与发展   4篇
一般理论   867篇
预防医学   197091篇
眼科学   58569篇
药学   191539篇
  5篇
中国医学   4747篇
肿瘤学   135718篇
  2018年   24936篇
  2016年   21266篇
  2015年   24321篇
  2014年   33746篇
  2013年   51760篇
  2012年   70278篇
  2011年   74438篇
  2010年   44281篇
  2009年   42195篇
  2008年   71239篇
  2007年   75616篇
  2006年   76512篇
  2005年   74477篇
  2004年   72885篇
  2003年   70039篇
  2002年   68639篇
  2001年   119671篇
  2000年   124157篇
  1999年   105420篇
  1998年   28993篇
  1997年   26275篇
  1996年   26562篇
  1995年   25638篇
  1994年   24177篇
  1993年   22625篇
  1992年   86021篇
  1991年   83896篇
  1990年   82100篇
  1989年   78768篇
  1988年   73048篇
  1987年   71961篇
  1986年   67912篇
  1985年   65467篇
  1984年   49065篇
  1983年   42039篇
  1982年   24666篇
  1981年   22190篇
  1980年   20496篇
  1979年   45992篇
  1978年   32083篇
  1977年   27052篇
  1976年   25463篇
  1975年   27171篇
  1974年   32716篇
  1973年   31527篇
  1972年   28996篇
  1971年   26884篇
  1970年   24980篇
  1969年   23202篇
  1968年   21197篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
101.
102.
103.
104.
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   
105.
科学研究的目标是创造和传播知识。这得通过对系统收集以及报告信息的批判性分析来完成。批判性分析始于一个简单的步骤,即在运用复杂统计学分析方法进行比较之前对所收集的数据进行深入检查。根据所收集的数据类型按照标准化方式进行统计学分析。在为解决研究问题而需采用合理、标准化步骤进行比较时,新知识就产生了,同时要避免错误的结论。在对数据进行仔细检查和分析之后,为了保证结论的正确性,再对数据进行一次批判性评论是非常重要的补充步骤。在科学文献中发表研究成果过程中涉及的同行评价对于传播新知识并保证其质量方面是一个非常重要的步骤。如果没有将研究成果发表供同行参考,这项研究就不算完整。  相似文献   
106.
107.
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   
108.
109.
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   
110.
G Pauletto  P Bergonzi 《Seizure》2006,15(3):150-155
The antiepileptic efficacy and tolerability of oxcarbazepine, used both as monotherapy and adjunctive therapy, were observed for 1 year in 202 adult patients, aged 17-83 years, with newly diagnosed or refractory partial epilepsy in clinical practice in Italy. At first observation, the seizure free rate was 72.2% in newly diagnosed patients given monotherapy, 40% in patients in whom oxcarbazepine replaced another monotherapy and 10.3% in patients given oxcarbazepine as adjunctive therapy. At least 50% reduction in seizure frequency was achieved in 90.7, 72 and 57%, respectively. Efficacy increased with the duration of treatment (p < 0.0001). In the 160 completers the seizure free rate was 61.3% with monotherapy and 28% with adjunctive therapy. 16.3% of patients reported adverse effects, mainly sedation and sleepiness; 5% discontinued oxcarbazepine because of adverse events. OXC is an effective and well-tolerated antiepileptic agent for the long-term treatment of partial epilepsy in adults.  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