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   1057篇
  免费   59篇
  国内免费   4篇
儿科学   79篇
妇产科学   14篇
基础医学   131篇
口腔科学   26篇
临床医学   110篇
内科学   245篇
皮肤病学   24篇
神经病学   42篇
特种医学   256篇
外科学   58篇
综合类   12篇
预防医学   37篇
眼科学   8篇
药学   35篇
中国医学   1篇
肿瘤学   42篇
  2023年   5篇
  2021年   6篇
  2020年   5篇
  2019年   6篇
  2018年   17篇
  2017年   13篇
  2016年   15篇
  2015年   16篇
  2014年   17篇
  2013年   28篇
  2012年   27篇
  2011年   20篇
  2010年   37篇
  2009年   43篇
  2008年   32篇
  2007年   22篇
  2006年   33篇
  2005年   16篇
  2004年   22篇
  2003年   21篇
  2002年   15篇
  2001年   9篇
  2000年   10篇
  1999年   16篇
  1998年   49篇
  1997年   67篇
  1996年   50篇
  1995年   41篇
  1994年   53篇
  1993年   52篇
  1992年   10篇
  1991年   11篇
  1990年   13篇
  1989年   39篇
  1988年   40篇
  1987年   28篇
  1986年   29篇
  1985年   27篇
  1984年   18篇
  1983年   22篇
  1982年   18篇
  1981年   19篇
  1980年   21篇
  1979年   6篇
  1978年   8篇
  1977年   12篇
  1976年   9篇
  1975年   17篇
  1930年   1篇
  1926年   1篇
排序方式: 共有1120条查询结果,搜索用时 15 毫秒
1.
2.
3.
4.
The genetic association between autism spectrum disorder (ASD) and psychotic disorders such as schizophrenia is complicated and mirrors the clinical overlap between these conditions to some degree. However, no studies to date have examined the genetics of individuals dually diagnosed with both ASD and psychosis. In this study, we present findings of copy number variants (CNVs) from a study of 116 well-characterised individuals with this dual diagnosis. DNA was extracted and arrayed using the Affymetrix CytoScan HD 2.8M array or the Affymetrix Cytogenetics arrays and compared with existing samples from the Database of Genomic Variants and the Simons Simplex Collection of CNVs from individuals with ASD and their families. Twenty-seven novel CNVs ≥20k base pairs were identified in the sample, most occurring in only a single individual, although two were found in two female participants. Forty-nine rare CNVs (<1.5% rate in general population) were also found at significantly higher frequencies than expected. The findings may provide evidence for areas of further study in the understanding of the development of both ASD and psychosis due to the number of affected genetic regions that have not previously been linked to these conditions.  相似文献   
5.
6.
7.
ObjectiveThe atlantodental interval (ADI) is used in assessing atlantoaxial stability. This measurement may potentially be affected by several features encountered during patient examination. This study examined the influence of 3 features: age, sex, and posture, on the measurement of ADI in a normal population.MethodsThe ADI was measured sequentially on 269 lateral cervical radiographs of adults with no demonstrated bony injury. Images were stratified by age and sex with equal representation in each age group. A further 25 asymptomatic adults were assessed for posture using craniovertebral angle measured from digital lateral photographs. The ADI was then measured from a lateral radiograph. The data were examined for correlation between age, craniovertebral angle, and ADI using Spearman rank correlation. The ADI of age groups was compared by Kruskal-Wallis test. The relationship between ADI and sex was examined using Wilcoxon rank sum test. Interaction between age and sex was explored using an interaction term in regression analysis.ResultsThe ADI decreased with age, median measurements reducing from 2.07 to 0.85 mm across age groups (P < .01). No significant relationship was demonstrated between ADI and sex. No significant interaction was demonstrated between age and sex. Measurements of craniovertebral angle did not correlate with ADI (ρ = 0.03, P = .90).ConclusionThe magnitude of ADI decreases with advancing age. Age should be considered a modifying factor when interpreting measurement of ADI, particularly in consideration of potential minor instabilities. Patient sex does not appear to influence ADI, either independently or in interaction with age. Craniocervical posture variation does not influence ADI in an asymptomatic adult population.  相似文献   
8.
Electrocardiographic (ECG) abnormalities in the setting of acute pulmonary embolism (PE) are being increasingly characterized and mounting evidence suggests that ECG plays a valuable role in prognostication for PE. We review the historical 21‐point ECG prognostic score for the severity of PE and examine the updated evidence surrounding the utility of ECG abnormalities in prognostication for severity of acute PE. We performed a literature search of MEDLINE, EMBASE, and PubMed up to February 2015. Article titles and abstracts were screened, and articles were included if they were observational studies that used a surface 12‐lead ECG as the instrument for measurement, a diagnosis of PE was confirmed by imaging, arteriography or autopsy, and analysis of prognostic outcomes was performed. Thirty‐six articles met our inclusion criteria. We review the prognostic value of ECG abnormalities included in the 21‐point ECG score, including new evidence that has arisen since the time of its publication. We also discuss the potential prognostic value of several ECG abnormalities with newly identified prognostic value in the setting of acute PE.  相似文献   
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