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   1336篇
  免费   73篇
  国内免费   4篇
耳鼻咽喉   8篇
儿科学   71篇
妇产科学   30篇
基础医学   149篇
口腔科学   45篇
临床医学   102篇
内科学   293篇
皮肤病学   25篇
神经病学   33篇
特种医学   419篇
外科学   86篇
综合类   39篇
预防医学   27篇
眼科学   6篇
药学   42篇
  1篇
肿瘤学   37篇
  2023年   4篇
  2021年   4篇
  2020年   5篇
  2019年   6篇
  2018年   9篇
  2017年   14篇
  2016年   10篇
  2015年   13篇
  2014年   30篇
  2013年   32篇
  2012年   16篇
  2011年   23篇
  2010年   36篇
  2009年   53篇
  2008年   22篇
  2007年   36篇
  2006年   28篇
  2005年   25篇
  2004年   18篇
  2003年   17篇
  2002年   10篇
  2001年   19篇
  2000年   12篇
  1999年   17篇
  1998年   80篇
  1997年   79篇
  1996年   80篇
  1995年   64篇
  1994年   40篇
  1993年   58篇
  1992年   6篇
  1991年   11篇
  1990年   25篇
  1989年   53篇
  1988年   41篇
  1987年   47篇
  1986年   52篇
  1985年   67篇
  1984年   35篇
  1983年   29篇
  1982年   28篇
  1981年   31篇
  1980年   37篇
  1979年   5篇
  1978年   18篇
  1977年   23篇
  1976年   21篇
  1975年   20篇
  1958年   1篇
  1914年   1篇
排序方式: 共有1413条查询结果,搜索用时 15 毫秒
91.
92.
93.
94.
95.
Finn  EJ; Di Chiro  G; Brooks  RA; Sato  S 《Radiology》1985,156(1):139-141
A number of surgical clips and other metallic materials embedded within patients have ferromagnetic properties that present a potential hazard when in the strong fields associated with magnetic resonance imaging. Several types of magnetometers and metal detectors were investigated as possible pre-imaging screening devices. The sensitivities and costs of these devices are given.  相似文献   
96.
Wienke A 《HNO》2005,53(5):467-472
Ohne Zusammenfassung
Current aspects of forensic lawFrom October 2004 to March 2005
  相似文献   
97.
98.
目的:高血压常伴有纤溶功能的异常,但其机制尚不清楚。本研究拟观察高静水压培养对人脐静脉内皮细胞(HUVECs)t-PA和PAI-1的影响以及卡托普利的干预效果,并探讨其可能的作用机制。方法:选用第4~6代HU-VECs,接种于24孔培养板中。依培养压力分为3组:大气压组(0mmHg),中压组(90mmHg),高压组(180mmHg)。在同一压力组,根据不同药物干预又分为两个亚组。即对照组(Ctrl)和卡托普利组(Cap,10^-5mol/L)。每组6份标本。采用ELISA法测定上清液t-PA和PAI-1的抗原浓度,并用细胞内总蛋白进行标化(单位:ng/μg proteins)。同时测定细胞内Ca^2+浓度(nmol/L)。结果:与大气压组相比,中压和高压组t-PA浓度均显著降低,PAI-1浓度显著增高,t-PA/PAI-1比值显著降低,[Ca^2+]i也显著增高。卡托普利对大气压组的t-PA、PAI-1和[Ca^2+]i无显著影响,但在两个高压组,卡托普利显著升高t-PA浓度,显著降低PAI-1浓度,t-PA/PAI-1比值显著升高,[Ca^2+]i显著地降低。结论:高静水压可损害内皮细胞的纤溶功能,而卡托普利的干预可降低高压所升高的[Ca^2+]i,并改善高静水压对内皮细胞纤溶功能的影响。  相似文献   
99.
Background--Currently, the reporting and archiving of echocardiographic data suffer from the difficulty of representing heart motion on printable 2-dimensional (2D) media. Methods and Results--We studied the capability of holography to integrate motion into 2D echocardiographic prints. Images of normal human hearts and of a variety of mitral valve function abnormalities (mitral valve prolapse, systolic anterior motion of the mitral leaflets, and obstruction of the mitral valve by a myxoma) were acquired digitally on standard echocardiographic machines. Images were processed into a data format suitable for holographic printing. Angularly multiplexed holograms were then printed on a prototype holographic "laser" printer, with integration of time in vertical parallax, so that heart motion became visible when the hologram was tilted up and down. The resulting holograms displayed the anatomy with the same resolution as the original acquisition and allowed detailed study of valve motion with side-by-side comparison of normal and abnormal findings. Comparison of standard echocardiographic measurements in original echo frames and corresponding hologram views showed an excellent correlation of both methods (P<0.0001, r2=0.979, mean bias=2.76 mm). In this feasibility study, both 2D and 3D holographic images were produced. The equipment needed to view these holograms consists of only a simple point-light source. Conclusions--Holographic representation of myocardial and valve motion from echocardiographic data is feasible and allows the printing on a 2D medium of the complete heart cycle. Combined with the recent development of online holographic printing, this novel technique has the potential to improve reporting, visualization, and archiving of echocardiographic imaging.  相似文献   
100.
Eight cases of dermatomyositis in children admitted to Scottish hospitals between 1962 and 1972 have been reviewed. 6 of the 8 were currently in complete remission. In the other 2 cases the disease remained active in 1 and 1 had died of cardiac failure 6 years after the onset of disease. 5 had developed extensive soft tissue calcification for which 2 were treated with ethanehydroxydiphosphonate, one showing definite improvement and the other no change. All had been treated with corticosteroids and two in addition had had cytotoxic agents (methotrexate or cyclophosphamide). The overal prognosis had probably been improved by the use of corticosteroids but not by the cytotoxic drugs. Only one of the patients was incapacitated by residual contractures or calcinosis.  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