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   2523篇
  免费   160篇
  国内免费   10篇
耳鼻咽喉   16篇
儿科学   52篇
妇产科学   119篇
基础医学   260篇
口腔科学   80篇
临床医学   328篇
内科学   561篇
皮肤病学   43篇
神经病学   134篇
特种医学   111篇
外科学   468篇
综合类   55篇
一般理论   22篇
预防医学   204篇
眼科学   13篇
药学   83篇
肿瘤学   144篇
  2022年   12篇
  2021年   33篇
  2020年   26篇
  2019年   44篇
  2018年   51篇
  2017年   31篇
  2016年   40篇
  2015年   39篇
  2014年   60篇
  2013年   68篇
  2012年   127篇
  2011年   130篇
  2010年   87篇
  2009年   71篇
  2008年   116篇
  2007年   115篇
  2006年   123篇
  2005年   125篇
  2004年   119篇
  2003年   97篇
  2002年   102篇
  2001年   68篇
  2000年   62篇
  1999年   70篇
  1998年   38篇
  1997年   45篇
  1996年   31篇
  1995年   33篇
  1994年   22篇
  1993年   24篇
  1992年   34篇
  1991年   53篇
  1990年   52篇
  1989年   51篇
  1988年   39篇
  1987年   40篇
  1986年   49篇
  1985年   40篇
  1984年   28篇
  1983年   24篇
  1981年   18篇
  1980年   15篇
  1979年   29篇
  1978年   21篇
  1977年   16篇
  1976年   15篇
  1975年   21篇
  1974年   19篇
  1973年   23篇
  1972年   18篇
排序方式: 共有2693条查询结果,搜索用时 171 毫秒
1.
2.
To increase our understanding of Candida pathogenicity, the identification of those strains most frequently associated with infections is of paramount importance. Polymerase chain reaction (PCR)‐based methods are extremely effective in differentiating and determining reproducibility, they require minimum starting material and are rapid and simple to perform. In this study, the genetic relatedness of Candida albicans was assessed for two geographically different patient groups (London, UK and Parma, Italy) affected by diabetes mellitus. C. albicans samples from the oral cavities of non‐diabetic healthy subjects were also examined by PCR fingerprinting to evaluate the possible genetic differences among endogenous strains in individuals with and without diabetes mellitus. PCR fingerprinting, with subsequent phylogenetic analysis of C. albicans isolates from the diabetic patients from London and Italy and from the non‐diabetic subjects, revealed that there were significant differences (P < 0.0001) between C. albicans isolates indicative of the distinct ecological niches that occur in the oral cavities of these patient cohorts. The most diverse group comprised the isolates from the diabetic patients in the UK, possibly reflecting the antifungal treatment that these patients had received. Further studies that include isolates from patient cohorts with systemic diseases other than diabetes mellitus, and from more diverse geographic localities are required to explain the relatedness of C. albicans isolates in the mouth.  相似文献   
3.
Development of the New Lung Allocation System in the United States   总被引:2,自引:2,他引:0  
This article reviews the development of the new U.S. lung allocation system that took effect in spring 2005. In 1998, the Health Resources and Services Administration of the U.S. Department of Health and Human Services published the Organ Procurement and Transplantation Network (OPTN) Final Rule. Under the rule, which became effective in 2000, the OPTN had to demonstrate that existing allocation policies met certain conditions or change the policies to meet a range of criteria, including broader geographic sharing of organs, reducing the use of waiting time as an allocation criterion and creating equitable organ allocation systems using objective medical criteria and medical urgency to allocate donor organs for transplant. This mandate resulted in reviews of all organ allocation policies, and led to the creation of the Lung Allocation Subcommittee of the OPTN Thoracic Organ Transplantation Committee. This paper reviews the deliberations of the Subcommittee in identifying priorities for a new lung allocation system, the analyses undertaken by the OPTN and the Scientific Registry for Transplant Recipients and the evolution of a new lung allocation system that ranks candidates for lungs based on a Lung Allocation Score, incorporating waiting list and posttransplant survival probabilities.  相似文献   
4.
5.
6.
Defecography in multiple sclerosis patients with severe constipation   总被引:3,自引:0,他引:3  
Gill  KP; Chia  YW; Henry  MM; Shorvon  PJ 《Radiology》1994,191(2):553
  相似文献   
7.
When medical students become involved in patient care, concerns are raised that have ethical and possibly legal implications. In order to determine compliance with the guidelines of the U.S. government and the Joint Committee on Accreditation of Hospitals pertaining to informed consent, the authors conducted a study of hospital administrators, medical school department chairpersons, and medical school deans (with response rates ranging from 82.3 to 95.1 percent) concerning policies on student involvement in patient care. The results show that only 37.5 percent of all responding teaching hospitals specifically informed patients that students would be involved in care. Only 51 percent of the responding medical schools that specifically gave their students instruction or guidance on initial patient interaction as a matter of policy insisted that their students introduce themselves as students and clarify their role in patient care. The authors conclude that medical educators' compliance with the ethical requirements of informed consent is incomplete.  相似文献   
8.
9.
10.
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