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   16561篇
  免费   1068篇
  国内免费   533篇
耳鼻咽喉   136篇
儿科学   125篇
妇产科学   79篇
基础医学   1332篇
口腔科学   520篇
临床医学   1578篇
内科学   887篇
皮肤病学   63篇
神经病学   705篇
特种医学   558篇
外科学   3170篇
综合类   2948篇
预防医学   1694篇
眼科学   76篇
药学   2417篇
  28篇
中国医学   1702篇
肿瘤学   144篇
  2024年   61篇
  2023年   244篇
  2022年   655篇
  2021年   792篇
  2020年   654篇
  2019年   525篇
  2018年   515篇
  2017年   567篇
  2016年   703篇
  2015年   621篇
  2014年   1344篇
  2013年   1403篇
  2012年   1279篇
  2011年   1324篇
  2010年   1016篇
  2009年   835篇
  2008年   784篇
  2007年   748篇
  2006年   642篇
  2005年   527篇
  2004年   447篇
  2003年   384篇
  2002年   273篇
  2001年   243篇
  2000年   207篇
  1999年   156篇
  1998年   144篇
  1997年   127篇
  1996年   107篇
  1995年   92篇
  1994年   81篇
  1993年   77篇
  1992年   79篇
  1991年   61篇
  1990年   52篇
  1989年   54篇
  1988年   54篇
  1987年   52篇
  1986年   27篇
  1985年   35篇
  1984年   28篇
  1983年   27篇
  1982年   23篇
  1981年   25篇
  1980年   14篇
  1979年   12篇
  1978年   12篇
  1977年   12篇
  1976年   4篇
  1973年   6篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
71.
Factors affecting choice between a managed care organization(MCO) and a fee-for-service insurance plan were examined whenthe University of Geneva health insurance plan was transformedinto an MCO, in October 1992. A case-control study using a mailedquestionnaire (response rate 84%) was conducted to compare formermembers who joined the MCO (joiners, n=421) to former memberswho opted out in order to keep fee-for-service coverage (non-joiners,n=222). Non-joiners were more likely to be women (odds ratio(OR) from multivariate model was 1.15, p=0.50), to be born inSwitzerland (OR=2.04, p<0.01), to have an annual income >75,000Swiss francs (OR=2.00, p<0.01), to have a personal physician(OR=1.96, p<0.01) and to have consulted a specialist (OR=1.69,p=0.02) or used unconventional medicine (OR=4.59, p<0.01)in the past year. During the previous year, non-joiners hadmore health care visits than joiners (14.6 versus 9.1, p=0.01).Non-joiners reported better mental health and fewer complainedof persistent fatigue (OR=2.18, p=0.03). The choice of healthplan was strongly influenced by socio-demographic characteristics,past patterns of health services utilization and health status.The self-selection process was paradoxical: MCO joiners hadused fewer health care visits than non-joiners, but their self-reportedhealth status was worse. The differences we have observed betweenself-selected populations have important implications for thefinancial performance of competing health care delivery systems.  相似文献   
72.
颈椎前路钢板在脊髓型颈椎病前路手术中的作用   总被引:10,自引:2,他引:8  
目的 评价内固定在脊髓型颈椎病前路减压中的作用。方法 143例脊髓型颈椎病患者经前路减压后自体髂骨植骨,带锁钢板内固定。获得随访病例132例,随访时间平均20个月,观察术后神经功能恢复情况,植骨融合率,椎间高度及颈椎生理曲度恢复情况。结果 单节段与两节段病变者术后3月均获得骨性愈合,融合率为100%,16例3节段病变者融合体为81.3%,内固定并发症为5/132(3.8%)。术后椎间高度与生理曲度均获得满意重建。JOA记分平均改善率65.8%。结论 在脊髓型颈椎病前路减压手术中应用带锁钢板内固定可有效维持椎间高度和生理曲度,并有助于后路间接减压。  相似文献   
73.
基于组合不变量配准的数字减影算法   总被引:2,自引:1,他引:1  
在现代医学中,DSA是X光片血管可视化技术的重要组成部分之一,在DSA中图像配准对消除运动伪影起着关键作用。运用一种基于组合不变量的相似度测量的模板匹配和弹性TPS算法配准减影方法,并根据实际情况有所改进。经过试验证明这种方法可以自动并有效地去除运动伪影,其速度和血管图像质量均比较理想。  相似文献   
74.
生物胶复合物加解剖钢板内固定治疗胫骨平台骨折   总被引:3,自引:0,他引:3  
目的探讨生物胶复合物加解剖钢板内固定治疗胫骨平台骨折的临床效果。方法采用切开复位、生物胶复合物植骨加解剖型支撑钢板内固定治疗胫骨平台骨折28例,受伤至手术时间5~10d,植入复合物量为3~8g。结果所有患者均获随访,随访6~24个月,全部骨折均获得临床愈合,未见关节面下陷,生物胶复合物中羟基磷灰石未见移动及吸收,治疗效果参照M echant评分标准,优13例,良11例,可3例,差1例,总优良率达85.3%。结论生物胶复合物加解剖钢板内固定治疗胫骨平台骨折的临床效果良好。生物胶复合物具有较强的成骨能力,可修复骨缺损。  相似文献   
75.
During maturation, most proteins undergo different posttranslational modifications. In most simple cases, signal peptidases remove the signal or leader peptide from the precursors of the secretory proteins during their translocation across the ER membrane. For biologically active proteins, such as enzymes, regulatory and defense proteins, toxins, etc., additional maturation-regulating mechanisms were shown to proceed with limited proteolysis of inactive precursors by specific enzymes. A number of specific enzymes from different cell types selectively cleave proproteins at specific processing sites. In this work, we analyzed the sequences of protein precursors synthesized in the excretory glands of different animals and identified new, non-traditional processing sites. They differ from the motifs previously identified in secreted proteins' precursors and enabled us to reconstruct the sequence of events leading to the conversion of protein precursors into the final products (mature proteins). We also found that in animals, the maturation mechanism of secretory and excretory proteins and the set of enzymes involved are species specific. The processing sites identified in protein precursors in this study are useful for a more detailed genome analysis and more accurate mature protein sequence prediction.  相似文献   
76.
作者应用改制的弯形麦氏接骨板内固定治疗股骨粗隆下骨折28例。经随访3~6个月,平均4个月骨折达临床愈合,14~20个月,平均16个月达骨性愈合。优良25例,优良率为89.3%。认为改制的弯形麦氏接骨板内固定牢固可靠。除严重粉碎性骨折一般不需外固定,病人可早期活动,加速骨折愈合。  相似文献   
77.
Mice immunized against anti-substance P (anti-SP) monoclonal antibodies produced anti-SP anti-idiotypic antibodies (SPAb2). In a previous report. SPAb2 antibodies were found to have in vitro biological activity i.e. to behave either as agonists or as antagonists for substance P (SP) depending on the biological test. In this study, the involvement of SPAb2 in vivo biological activity has been tested. Because of the possible implication of SP in the generation and transmission of nociceptive information, we have tested the responsiveness of SPAb2 responding mice in behavioral nociceptive tests. SPAb2 mice showed very small behavioral variations in the hot plate test as compared with a control group of mice immunized against an unrelated monoclonal antibody. In the formalin test, however, SPAb2 mice displayed a significant increase in paw licking time, which was significantly correleted with SPAb2 serum concentration. These results are discussed in terms of the use of SPAb2 as pharmacological tools for studying the biological properties of SP receptors and more generally of auto anti-idiotypic antibodies in modulating behavior responses.  相似文献   
78.
The conceptual and methodological framework proposed by Doss (this issue) makes valuable suggestions for strategic choices in future research. This commentary addresses conceptual and terminological distinctions adopted by Doss, as well as his criticism of add-on/ dismantling studies. We also suggest research topics and methodological developments that could be integrated in Doss's framework to further expand understanding of therapeutic change.  相似文献   
79.
髋臼钛板加颗粒植骨治疗髋臼严重骨缺损   总被引:1,自引:0,他引:1  
[目的]探讨髋臼钛板加颗粒植骨治疗髋臼严重骨缺损的临床效果。[方法]应用该技术治疗27例患者,髋臼骨缺损分型(AAOS分类)Ⅰ型6例,ⅡC型4例,Ⅲ型17例;术前髋关节Harris评分平均37分,术后根据临床及x线进行评估。[结果]所有患者均采用该方法重建髋臼,术后假体脱位1例,原因是重建钛板前倾过多与大粗隆发生撞击,经凿去部分粗隆骨质消除撞击因素后治愈。其余病例无并发症,平均随访3a,Harris评分平均87分。X线无1例患者的髋臼骨床、移植骨、重建钛板和聚乙烯内衬交界面出现透亮带。[结论]髋臼钛板加颗粒植骨可有效修复髋臼骨缺损,为假体提供坚强的初始固定,具有恢复髋关节旋转中心的作用。  相似文献   
80.
目的评价脊髓型颈椎病前路减压后应用带锁钛板内固定的价值。方法对51例脊髓型颈椎病患者采用前路减压、取自体髂骨植骨和颈椎带锁钛板内固定治疗。结果随访43例,平均随访时间2a,术后3个月植骨块获得骨性融合,颈椎椎间高度和生理曲度维持满意,感觉、肌力明显恢复,钛板及螺钉无松动及断裂现象。结论脊髓型颈椎病前路减压术后应用带锁钛板内固定能促使植骨块融合,有效地维持椎间高度和颈椎生理曲度,有较高的应用价值。  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