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   1245篇
  免费   170篇
  国内免费   4篇
耳鼻咽喉   4篇
儿科学   60篇
妇产科学   7篇
基础医学   225篇
口腔科学   30篇
临床医学   97篇
内科学   352篇
皮肤病学   5篇
神经病学   220篇
特种医学   65篇
外科学   47篇
综合类   25篇
预防医学   169篇
眼科学   7篇
药学   66篇
中国医学   4篇
肿瘤学   36篇
  2022年   12篇
  2021年   12篇
  2019年   12篇
  2018年   22篇
  2017年   11篇
  2016年   17篇
  2015年   27篇
  2014年   28篇
  2013年   26篇
  2012年   52篇
  2011年   52篇
  2010年   38篇
  2009年   18篇
  2008年   63篇
  2007年   50篇
  2006年   72篇
  2005年   55篇
  2004年   40篇
  2003年   50篇
  2002年   50篇
  2001年   41篇
  2000年   39篇
  1999年   40篇
  1998年   33篇
  1997年   22篇
  1996年   29篇
  1995年   22篇
  1994年   18篇
  1993年   16篇
  1992年   36篇
  1991年   25篇
  1990年   33篇
  1989年   21篇
  1988年   23篇
  1987年   25篇
  1986年   19篇
  1985年   28篇
  1984年   23篇
  1983年   17篇
  1982年   13篇
  1981年   15篇
  1980年   13篇
  1979年   21篇
  1978年   18篇
  1977年   10篇
  1976年   15篇
  1975年   12篇
  1974年   10篇
  1971年   10篇
  1969年   8篇
排序方式: 共有1419条查询结果,搜索用时 0 毫秒
151.
152.
153.
154.
Positron emission tomography was used with [11C] flumazenil (FMZ) and [18F] fluorodeoxyglucose to study GABA type A/benzodiazepine (GABA-A/BDZ) receptors and cerebral metabolic rates for glucose (1CMRglc) in 17 male patients with severe chronic alcoholism (ALC), 8 with (ACD) and 9 without alcoholic cerebellar degeneration (non-ACD). In comparison with male normal controls of similar ages, the ALC group had significantly reduced FMZ ligand influx (K1), FMZ distribution volume (DV), and 1CMRglc bilaterally in the medial frontal lobes, including superior frontal gyrus and rostral cingulate gyrus; the ACD group had significant reductions of K1, DV, and ICMRglc bilaterally in the same distribution, and also in the superior cerebellar vermis; and the non-ACD group had significant reductions of K1, DV, and ICMRglc bilaterally in the same regions of the frontal lobes but not in the superior cerebellar vermis. When compared with the non-ACD group, the ACD group had significant reductions of K1 and DV bilaterally in the superior cerebellar vermis. The results suggest that severe chronic alcoholism damages neurons containing GABA-A/BDZ receptors in the superior medial apsects of the frontal lobes, and in patients with clinical signs of ACD, neurons containing GABA-A/BDZ receptors in the superior cerebellar vermis.  相似文献   
155.
Multiple system atrophy (MSA) is characterized clinically by Parkinsonism, cerebellar dysfunction, and autonomic impairment. Multiple mutations in the LRRK2 gene are associated with parkinsonian disorders, and the most common one, the G2019S mutation, has been found in approximately 1% of sporadic cases of Parkinsonism. In a well-characterized cohort of 136 subjects with probable MSA and 110 neurologically evaluated control subjects, none carried the G2019S mutation. We conclude that the G2019S mutation in the LRRK2 gene is unlikely to be associated with MSA.  相似文献   
156.
157.
To determine the prevalence of cysticercosis in a rural area where the disease is endemic, the authors studied the seroepidemiology of human and porcine cysticercosis in a Peruvian jungle community (Maceda, Peru) in 1988 using an enzyme-linked immunoelectrotransfer blot (EITB) assay. Of the 371 sampled inhabitants, 30 (8%) were seropositive, most of whom were asymptomatic. After niclosamide therapy, four Taenia species worms were identified in the seropositive group, compared with one in the control group (p = 0.06). Pigs were frequently infected: 44 of 133 (33%) were found positive for Taenia by tongue examination and 57 of 133 (43%) were positive by EITB. In 69% of the sampled households that had pigs, there was at least one seropositive pig. The number of pigs diagnosed positive by the tongue examination was significantly greater in households that had latrines than in those that did not. Cysticercosis is a common but usually asymptomatic infection that affects both humans and pigs in the high jungle areas of Peru.  相似文献   
158.
Stool microscopy and an enzyme-linked immunosorbent assay (ELISA) for Giardia lamblia antigen detection were compared for detecting G. lamblia in 30 Peruvian infants. Of 1,131 fecal specimens, G. lamblia was detected by ELISA alone in 44, by microscopy alone in 17, and by both methods in 91. In another group of 17 children negative for G. lamblia by stool microscopy, 6 had G. lamblia detected by ELISA or duodenal aspiration: 2 only by ELISA, 1 only by duodenal aspirate examination, and 3 by both examinations. The ELISA is useful for the detection of G. lamblia in fecal specimens but compared to stool microscopy does not significantly increase the detection of cases.  相似文献   
159.
INTRODUCTION: At present there is no curriculum to guide physician lifelong learning in a prescribed, deliberate manner. The Conjoint Committee on Continuing Medical Education, a group representing 16 major stakeholder organizations in continuing medical education, recommends that each specialty society and corresponding board reach consensus on the competencies expected of physicians in that specialty. Experts in a specialty will define content-based core competencies in the areas of patient care, medical knowledge, practice-based learning and improvement, interpersonal and communication skills, professionalism, and systems-based practice. These competencies, when cross-referenced with expertise, comprise a framework for specialty curricula and board maintenance of certification programs. The American Academy of Ophthalmology and the American Board of Ophthalmology already have implemented this recommendation. Their work is reported as a model for further development. A competency-based curriculum framework offers a foundation for continuing medical education in diverse practice settings and provider organizations.  相似文献   
160.
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