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   6084篇
  免费   422篇
  国内免费   77篇
耳鼻咽喉   106篇
儿科学   140篇
妇产科学   61篇
基础医学   631篇
口腔科学   110篇
临床医学   584篇
内科学   748篇
皮肤病学   66篇
神经病学   895篇
特种医学   159篇
外科学   276篇
综合类   848篇
一般理论   4篇
预防医学   961篇
眼科学   88篇
药学   589篇
  5篇
中国医学   180篇
肿瘤学   132篇
  2023年   106篇
  2022年   107篇
  2021年   213篇
  2020年   197篇
  2019年   249篇
  2018年   243篇
  2017年   225篇
  2016年   201篇
  2015年   181篇
  2014年   450篇
  2013年   582篇
  2012年   379篇
  2011年   421篇
  2010年   328篇
  2009年   309篇
  2008年   305篇
  2007年   285篇
  2006年   252篇
  2005年   192篇
  2004年   151篇
  2003年   143篇
  2002年   117篇
  2001年   96篇
  2000年   80篇
  1999年   70篇
  1998年   72篇
  1997年   52篇
  1996年   40篇
  1995年   50篇
  1994年   52篇
  1993年   33篇
  1992年   42篇
  1991年   34篇
  1990年   28篇
  1989年   40篇
  1988年   28篇
  1987年   22篇
  1986年   11篇
  1985年   37篇
  1984年   19篇
  1983年   19篇
  1982年   18篇
  1981年   13篇
  1980年   13篇
  1979年   9篇
  1977年   9篇
  1976年   8篇
  1975年   15篇
  1974年   7篇
  1973年   9篇
排序方式: 共有6583条查询结果,搜索用时 15 毫秒
1.
ObjectiveTo identify how individuals respond to unilateral upper extremity peripheral nerve injury via compensation (increased use of the nondominant hand). We hypothesized that injury to the dominant hand would have a greater effect on hand use (left vs right choices). We also hypothesized that compensation would not depend on current (postinjury) nondominant hand performance because many patients undergo rehabilitation that is not designed to alter hand use.DesignObservational survey, single-arm.SettingsAcademic research institution and referral center.ParticipantsA total of 48 adults (N=48) with unilateral upper extremity peripheral nerve injury. Another 14 declined participation. Referred sample, including all eligible patients from 16 months at 1 nerve injury clinic and 1 hand therapy clinic.InterventionsNot applicable.Main Outcome MeasuresHand use (% of actions with each hand) via Block Building Task. Dexterity via Jebsen-Taylor Hand Function.ResultsParticipants preferred their dominant hand regardless of whether it was injured: hand usage (dominant/nondominant) did not differ from typical adults, regardless of injured side (P>.07), even though most participants (77%) were more dexterous with their uninjured nondominant hand (mean asymmetry index, ?0.16±0.25). The Block Building Task was sensitive to hand dominance (P=2 × 10?4) and moderately correlated with Motor Activity Log amount scores (r2=0.33, P<.0001). Compensation was associated only with dominant hand dexterity (P=3.9 × 10?3), not on nondominant hand dexterity, rehabilitation, or other patient and/or injury factors (P>.1).ConclusionsPatients with peripheral nerve injury with dominant hand injury do not compensate with their unaffected nondominant hand, even if it is more dexterous. For the subset of patients unlikely to recover function with the injured hand, they could benefit from rehabilitation that encourages compensation with the nondominant hand.  相似文献   
2.
Network meta-analyses (NMAs) simultaneously estimate the effects of multiple possible treatment options for a given clinical presentation. For allergists to benefit optimally from NMAs, they must understand the process and be able to interpret the results. Through a worked example published in Pediatric Allergy and Immunology, we summarize how to identify credible NMAs and interpret them with a focus on recent innovations in the GRADE approach (Grading of Recommendations Assessment, Development, and Evaluation). NMAs build on traditional systematic reviews and meta-analyses that consider only direct paired comparisons by including indirect evidence, thus allowing the simultaneous assessment of the relative effect of all pairs of competing alternatives. Our framework informs clinicians of how to identify credible NMAs and address the certainty of the evidence. Trustworthy NMAs fill a critical gap in providing key inferences using direct and indirect evidence to inform clinical decision making when faced with more than two competing courses of treatment options. This document will help allergists to identify trustworthy NMAs to enhance patient care.  相似文献   
3.
Identifying transmission of hot spots with temporal trends is important for reducing infectious disease propagation. Cluster analysis is a particularly useful tool to explore underlying stochastic processes between observations by grouping items into categories by their similarity. In a study of epidemic propagation, clustering geographic regions that have similar time series could help researchers track diffusion routes from a common source of an infectious disease. In this article, we propose a two-stage scan statistic to classify regions into various geographic clusters by their temporal heterogeneity. The proposed scan statistic is more flexible than traditional methods in that contiguous and nonproximate regions with similar temporal patterns can be identified simultaneously. A simulation study and data analysis for a dengue fever infection are also presented for illustration.  相似文献   
4.
视觉通路包括视神经、视交叉、视束、视放射及视皮质。常规磁共振检查技术难以发现视路损伤后白质纤维微结构改变,眼科学检查也存在一定的局限性及主观性,且不能探测后视路的变化。弥散张量成像(diffusion tensor imaging,DTI)作为一种新兴的磁共振成像技术,通过各种后处理分析方法结合不同的参数进行分析,可提供组织的微结构信息,并能够直观显示活体白质纤维束,在无创地探索疾病的神经病理机制、评估预后方面起着重要的作用。近年来随着DTI后处理方法的不断创新,其在视路损伤中的研究越来越多。本文在介绍DTI的主要参数及常见脑白质微结构分析方法的同时,阐述了其在视路损伤研究中的应用,并进一步对各种分析方法的优缺点进行总结。  相似文献   
5.
6.
7.
8.
BackgroundComputerized dynamic posturography is commonly used to assess balance in service members, but normative values for the military population have not been established.Research questionWhat are the normative values for the Motor Control Test (MCT), Sensory Organization Test (SOT) and the enhanced SOT (eSOT) within the military population and at which point do they differ?MethodsCross-sectional study. 237 active duty service members (78 % male) completed the MCT, SOT and the eSOT with the sway manipulated at a gain of 1.2, 1.4, 1.6, 1.8, or 2.0. A Mann-Whitney U test was used to compare the means of men and women for the SOT and MCT composite scores. A Kruskal-Wallis H test was used to compare the means of age groups for the SOT composite score. An independent t-test was used to compare the SOT composite scores from our military population to the manufacturer’s normative (civilian) data. The means and standard deviations for the eSOT scores were reported for each gain. Paired-samples t-tests were performed to compare the SOT composite score with the eSOT composite score for each level of gain.ResultsThere was no difference between SOT composite scores for men and women (Mann-Whitney U = 4363.50, p = 0.19) or among age groups (Kruskal-Wallis = 2.77, p = 0.25). The mean SOT composite scores were not different from the manufacturer’s normative values (p = 0.155). SOT composite scores were significantly higher than eSOT composite scores for gains of 1.4 (t = 3.16, p = 0.003), 1.6 (t = 5.73, p < 0.001), 1.8 (t = 5.26, p < 0.001) and 2.0 (t = 5.89, p < 0.001). MCT composite scores were lower in the 18−26 year old than the 36−45 year old age group (p = 0.013).SignificanceThis study establishes normative values for the MCT, SOT and eSOT in active duty military service members. The results suggest that the manufacturer’s normal values are appropriate for making judgments about the postural stability of service members.  相似文献   
9.
10.
目的:分析大学生体力活动水平与烟草依赖性之间的相关性,探讨不同体力活动水平对大学生烟草依赖性的影响。方法:以133名吸烟男性大学生为研究对象,运用国际体力活动问卷(IPAQ)和尼古丁依赖检验量表(FTND)等测量工具,分别评估体力活动水平和烟草依赖程度。采用Spearman相关分析的方法检验体力活动与烟草依赖的相关性,采用多独立样本非参数检验(Kruskal-Wallis单因素ANOVA)的方法,检验不同体力活动水平之间烟草依赖性的差异。结果:吸烟男大学生体力活动水平为5124.28±3381.43 MET-min/w,烟草依赖程度为2 (0~4)分,非参数相关分析Spearman’s rho=-0.21,P<0.05。与低体力活动水平组相比,高、中体力活动水平组大学生的烟草依赖性分别存在显著差异性[6(2.25~8)vs. 1(0~4),P<0.01;6(2.25~8)vs. 2(0~4),P<0.05]。高、中体力活动水平组大学生之间的烟草依赖性差异无统计学意义[1(0~4) vs.2(0~4),P>0.05]。结论:大学生体力活动水平与烟草依赖程度呈负相关。高、中体力活动水平大学生的烟草依赖程度较低,两组之间无显著差异。  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