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   2397篇
  免费   148篇
  国内免费   6篇
耳鼻咽喉   14篇
儿科学   46篇
妇产科学   31篇
基础医学   408篇
口腔科学   91篇
临床医学   236篇
内科学   484篇
皮肤病学   22篇
神经病学   236篇
特种医学   77篇
外科学   223篇
综合类   16篇
一般理论   2篇
预防医学   197篇
眼科学   45篇
药学   214篇
肿瘤学   209篇
  2023年   16篇
  2022年   17篇
  2021年   32篇
  2020年   37篇
  2019年   53篇
  2018年   53篇
  2017年   46篇
  2016年   51篇
  2015年   51篇
  2014年   84篇
  2013年   116篇
  2012年   143篇
  2011年   158篇
  2010年   87篇
  2009年   93篇
  2008年   145篇
  2007年   127篇
  2006年   149篇
  2005年   164篇
  2004年   115篇
  2003年   98篇
  2002年   112篇
  2001年   31篇
  2000年   40篇
  1999年   42篇
  1998年   21篇
  1997年   20篇
  1996年   28篇
  1995年   26篇
  1994年   18篇
  1993年   16篇
  1992年   22篇
  1991年   23篇
  1990年   16篇
  1989年   20篇
  1988年   16篇
  1987年   20篇
  1986年   16篇
  1985年   13篇
  1984年   15篇
  1983年   21篇
  1982年   12篇
  1979年   13篇
  1976年   9篇
  1974年   8篇
  1972年   12篇
  1968年   9篇
  1928年   9篇
  1927年   8篇
  1926年   10篇
排序方式: 共有2551条查询结果,搜索用时 15 毫秒
1.
2.
We thank Geluk and Zijlstra for their kind words as well astheir considerations and proposals. The latter hits right intothe heart of the issue: should one stick to the ‘anatomic’paradigm urging us to detect and treat coronary stenoses andcalcifications rather than follow  相似文献   
3.
In a prospective, randomized trial, 104 consecutive patients with displaced femoral neck fractures were allocated either to fixation with a sliding screw plate or 4 ASIF cancellous bone screws. The patients were reexamined at fixed intervals to determine the time of union. The 2-year-cumulated rate of union was 64 per cent in the plate group and 84 per cent in the screw group.  相似文献   
4.
5.
6.
Five female patients with Klippel-Feil syndrome (KFS) are presented with abnormal bony masses in the mandibular ramus region. The features of KFS are described with assessment and treatment of the five patients. Although congenital duplication of mandibular rami in KFS has been previously documented, we believe this is the first series of patients with this deformity.  相似文献   
7.
This study describes mortality rates and predictors of mortality among late-middle-aged and older (55+) substance abuse inpatients ( n = 21, 139) in Department of Veterans Affairs (VA) Medical Centers in the 4 years after an index episode of care. A total of 24% of the patients died; this mortality rate was 2.64 times higher than expected. Predictors of earlier mortality included older age and nonmarried status, alcohol psychosis and organic brain disorder diagnoses, and several medical diagnoses, including neoplasms, liver cirrhosis, respiratory, endocrine and metabolic, and blood system disorders. Three proxy indicators of illness severity also predicted mortality: more prior inpatient and outpatient medical care and an index episode in an extended care unit. In contrast, more prior outpatient mental health care and remitted status predicted lower mortality. These diagnostic and treatment indicators can be used to identify patients at heightened risk for premature mortality. Moreover, they show that intensive mental health aftercare and remission of substance abuse may delay mortality, even among older patients who have longstanding substance abuse problems.  相似文献   
8.
Summary.  Monoclonal antibodies Ds-1 and Ds-2 specifically labelling dog sperm acrosome were prepared by immunization of mice with acetic acid extracts of dog spermatozoa. Electron microscopy and indirect immunofluorescence localized the site of Ds-1 and Ds-2 proteins inside the acrosomal vesicle. Ds-1 antibody detected 55, 76, 115, 120 and 190kDa proteins under non-reducing conditions, and 73 kDa and 54 kDa proteins after reduction (p73/Ds-1 and p54/Ds-1). 92 kDa and 40 kDa proteins recognized by Ds-2 (p92/Ds-2 and p40/Ds-2) migrated at > 200 kDa in the absence of reducing agent. In vivo , p73/Ds-1 and p54/Ds-1 are therefore likely to be present both in free and complexed form, while all of p92/Ds-2 and p40/Ds-2 form disulfide-bonded complexes. Decrease in the rate of acrosomes stained with Ds-1 and Ds-2 was correlated with the progress of capacitation resulting in the increased rate of spontaneous acrosome reactions, as suggested by a dramatic effect of A23187. Monoclonal antibody to boar acrosin (ACR-2) recognized dog sperm acrosin homologue. A higher rate of ACR-2-negative spermatozoa was observed after capacitation and A23187 treatment compared to Ds-1 and Ds-2, indicating that proteins recognized by Ds-1 and Ds-2 are localized in a specific compartment of acrosome, distinct from acrosin and possibly representing fraction of acrosomal matrix.  相似文献   
9.
Summary One hundred thirty-one breast carcinomas with medullary features, registered in the Danish Breast Cancer Cooperative Group from 1977–1982, have been histopathologically reviewed by two senior pathologists and classified as typical medullary carcinoma (TMC), atypical medullary carcinoma (AMC), and non-medullary carcinoma (NMC). Diagnostic criteria were based on those put forward by Ridolfiet al. and Fisheret al. The procedure was repeated with an interval of about one year by both pathologists. The diagnostic interobserver agreement was 72% with a Kappa of 0.55. The intraobserver agreement was 77% and 63% with Kappa values of 0.64 and 0.44, respectively. To see whether the observed inter- and intraobserver variability had any prognostic implications, diagnostic subgroups for both pathologists were analyzed with Kaplan Meier plots for recurrence-free survival (RFS) and with log rank tests. In the first evaluation pathologist 1 segregated a group of TMC with a significantly better RFS than for the NMC group, and pathologist 2 segregated a group of TMC with a corresponding strong trend. These findings could not, however, be reproduced in the second evaluation. The study indicates that the criteria of TMC and AMC as proposed by Ridolfiet al. need to be sharpened and simplified in order to reduce inter-and intraobserver variability. Larger studies with a control group of infiltrating ductal carcinomas are mandatory to elucidate the clinical importance of the diagnoses of Typical and Atypical Medullary Carcinoma of the breast.  相似文献   
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