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   16729篇
  免费   1358篇
  国内免费   556篇
耳鼻咽喉   172篇
儿科学   326篇
妇产科学   389篇
基础医学   2151篇
口腔科学   334篇
临床医学   1972篇
内科学   3093篇
皮肤病学   342篇
神经病学   1101篇
特种医学   898篇
外国民族医学   3篇
外科学   1974篇
综合类   1174篇
一般理论   2篇
预防医学   1055篇
眼科学   464篇
药学   1436篇
  4篇
中国医学   338篇
肿瘤学   1415篇
  2023年   161篇
  2022年   402篇
  2021年   595篇
  2020年   322篇
  2019年   435篇
  2018年   430篇
  2017年   379篇
  2016年   394篇
  2015年   550篇
  2014年   643篇
  2013年   704篇
  2012年   1141篇
  2011年   1211篇
  2010年   742篇
  2009年   644篇
  2008年   885篇
  2007年   894篇
  2006年   834篇
  2005年   787篇
  2004年   702篇
  2003年   607篇
  2002年   531篇
  2001年   482篇
  2000年   420篇
  1999年   404篇
  1998年   231篇
  1997年   221篇
  1996年   235篇
  1995年   197篇
  1994年   150篇
  1993年   129篇
  1992年   216篇
  1991年   197篇
  1990年   178篇
  1989年   167篇
  1988年   162篇
  1987年   132篇
  1986年   127篇
  1985年   125篇
  1984年   95篇
  1983年   81篇
  1982年   73篇
  1981年   64篇
  1980年   60篇
  1979年   65篇
  1978年   56篇
  1977年   49篇
  1976年   34篇
  1975年   40篇
  1974年   43篇
排序方式: 共有10000条查询结果,搜索用时 203 毫秒
41.
CT影像学评分预测急性胰腺炎病情及转归的研究   总被引:2,自引:0,他引:2  
目的 探讨CT影像学评分对急性胰腺炎病情和转归的预测价值。方法 回顾性分析入院后经CT检查的急性胰腺炎46例,按一定的规则对每例患进行CT影像学评分与分型,并与临床治疗中的有关资料进行对照。结果 46例患CT评分后获得:轻型24例,中型13例,重型9例。轻型患较重型住院日少、恢复顺利,中转手术及死亡率均以重型为高。结论 CT评分对急性胰腺炎病情及预后评估具有重要意义。  相似文献   
42.
43.
矽肺患者肺功能与血气分析   总被引:1,自引:0,他引:1  
以67名Ⅱ、Ⅲ期矽肺患做了肺功能(VC,FVC,FEV,FEV1/FVC,MVV,DLCO和血气分析(PaO2,PaCogm2,pH)。结果表明Ⅲ期矽肺肺功能较Ⅱ期矽肺降低,其中VC,FVC、MVV降低有显著差异,PaO2和pH随矽肺期别增加呈降低有显著差异。PaO2降低尤为明显,PaCO2呈增高趋势。肺功能与PaO2改变显著相关,与PaCO2和PH无相关关系。PaO2〈10kPa发生率与尘肺劳动  相似文献   
44.
45.
46.
用PowerPoint XP设计幻灯片元素动画效果的实践   总被引:6,自引:1,他引:5  
PowerPoint XP新特性中突出的就是其动画设计功能的加强。文中对新增加的与动画没计相关的功能使用要点结合实际作了较详细的叙述。  相似文献   
47.
手部创伤性骨关节缺损的处理   总被引:4,自引:0,他引:4  
治疗手部骨关节缺损常采用植骨内固定、关节融合、关节成形及关节置换等方法.为总结经验,对1989年以来101例手部创伤性骨与关节缺损进行分析。单纯掌、指骨缺损39例,行直接短缩对位,克氏针内固定6例,1例发主骨不连;对33例缺损较大者用自体骨块植入克氏针交叉内固定,部分病例同时植人RBX或异体骨粒,10例发生延迟愈合,余全部正常愈合。骨与关节部分或完全缺损62例,采用关节成形术46例,其中以肋软骨移植效果最好,骨膜移植次之,筋膜衬垫或硅胶膜植入法较差;行关节融合术11例.均达顺利融合;采用自体关节置换5例,均成活,术后关节活动度均>70°。我们认为:自体骨块植入克氏针交叉内固定,必要时植入RBX骨粒.是治疗手部创伤性骨缺损的有效方法。关节缺损应按关节的重要性,分别采用关节融合术、关节成形术或关节置换术。  相似文献   
48.
Effects of posts on dentin stress distribution in pulpless teeth.   总被引:5,自引:0,他引:5  
A finite element analysis was carried out to study the roles of posts in reducing dentin stress in pulpless teeth. Two-dimensional plane strain models of the midlabiolingual section of a human maxillary central incisor were first analyzed. The results showed that the gold alloy post reduced maximal dentin stress by as much as 30%. However, the integrity of the dentin was compromised and the effects of the post were likely to be exaggerated in such models. In an effort to correct for these problems, plane stress models with side plates and axisymmetric models were analyzed. Posts were found to reduce maximal dentin stress by only 3% to 8% when the teeth were subjected to masticatory and traumatic loadings in these latter models. Although posts reduced maximal dentin stress by as much as 20% when the teeth were loaded vertically, teeth such as incisors and canines normally are not subjected to vertical loadings. Thus the reinforcement effects of posts seem to be doubtful in these teeth.  相似文献   
49.
SUMMARY A young patient presenting with splenomegaly and hypersplenism was inadvertently found to have selective IgA deficiency. There were no symptoms of immunodeficiency and the patient responded well to splenectomy, with return of blood counts to normal without adverse effects. No other cause for the hypersplenism was found. We postulate selective IgA deficiency as a cause of splenomegaly and hypersplenism.  相似文献   
50.
Laparoscopic nephrectomy was performed in 15 male pigs, the procedure was successful in 14. Extraction of the intact kidney through a 5-cm lower abdomen incision was done in 7 animals; complete destruction and evacuation of the kidney was accomplished by a round-knife suction device through a 1-cm port in another 7 pigs. Grossly, the specimen consisted of sausage-like tubular renal tissue and a small amount of tissue debris. Pathology revealed that the glomerular and tubular structures were well preserved, no interstitial hematoma could be found. Four ports were usually used, one 1-cm umbilical camera port, one 0.5-cm port for ureter traction, and two 1-cm working ports along the midclavicular line. All the pigs recovered uneventfully. The average operation time was 3 h 20 min. The application of endo-GIA (United States Surgical Corporation) for renal hilum reduced the operative time to 2 h 20 min. Complications included renal vein tear during endoclip application and cutting in the first case, mild subcutaneous emphysema in 2 cases. This first pig received exploratory laparotomy for the repair and ligation of the renal vein. No more major complications occurred with increasing experience. From this porcine experiment, we conclude that the combination of laparoscopy, a tissue destroyer and an endobag for the entrapment of kidney seem to be a promising technique for clinical nephrectomy.  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