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1.
BackgroundBody-worn inertial measurement unit (IMU) sensors have been widely used in postural stability and balance studies because of their low cost and convenience. In most of these studies, a single IMU sensor is attached to a waist belt near the body’s center of mass. Some populations such as pregnant women, however, may find a waist belt challenging in terms of fit and comfort. For this reason it may be useful to identify an alternative location for placement of an IMU and a more comfortable means for attaching the sensor to the body.Research questionDoes placing an IMU sensor in a pendant worn around the neck permit discrimination between conditions with varying postural stability?MethodsTwenty-six healthy participants performed three standing tasks (double-leg, tandem, and single-leg standing) under eyes-open and eyes-closed vision conditions to preliminarily assess the ability of the pendant sensor to discriminate between balance conditions. Discrimination based upon data from a belt-mounted IMU was assessed in the same trials. Differences in standard deviation of acceleration components, sway area, and jerkiness due to trial condition and sensor were evaluated using analysis of variance followed by post hoc comparisons. These data were also incorporated into receiver-operator characteristic (ROC) curve analysis to assess the effectiveness of each sensor at discriminating between conditions.ResultsStability was found to vary across conditions, but there was no interaction between stability and sensor location (all p ≥ 0.323). ROC curve analysis showed that sensors in both locations were good discriminators between conditions.SignificancePlacing an IMU in a pendant may be feasible for studying and monitoring postural instability. This approach may be especially valuable when considering populations for which wearing a belt is uncomfortable.  相似文献   
2.
目的了解目前我国创伤临床病例研究的主要应用手段和研究水平。方法对中华骨科学会创伤学组2002年年会投稿临床病例研究稿件进行总结分析,对稿件论述的研究范围、研究对象、病例数量、骨折分类、研究方法、随访评价、统计分析应用等方面进行统计研究。结果大会收到225篇稿件。其中随访临床病例报告180篇。报告病例1万多例、范围广,包括了当前主要的临床治疗方法。回顾性研究中,对临床资料进行统计学分析的论文仅占少数(6.1%)。对骨折分类方法及临床随访结果评价标准不统一,欠规范。无前瞻性研究报告。结论创伤临床病例研究方法有待进一步改进。  相似文献   
3.
The Institute of Medicine distinguishes between programs based on who is targeted: the entire population (universal), those at risk (selective), or persons exhibiting the early stages of use or related problem behavior (indicated). Evaluations suggest that although universal programs can be effective in reducing and preventing substance use, selective and indicated programs are both more effective and have greater cost-benefit ratios. This paper tests these assumptions by comparing the impact of these program types in reducing and preventing substance use at the individual level (i.e., those exposed to intervention services) and in the population (i.e., those exposed and not exposed to intervention services). A meta-analysis was performed on 43 studies of 25 programs to examine program comparability across IOM categories. When examining unadjusted effect sizes at the individual level, universal programs were modestly more successful in reducing tobacco use, but selective and indicated programs were modestly more successful in reducing alcohol and marijuana use. When adjusted to the population level, the average effect sizes for selective and indicated programs were reduced by approximately half. At the population level, universal programs were more successful in reducing tobacco and marijuana use and selective and indicated programs were more successful in reducing alcohol use. Editors’ Strategic Implications: The authors’ focus on the public health value of a prevention strategy is compelling and provides a model for analyses of other strategies and content areas.  相似文献   
4.
Few cases in the history of epidemiology and public health are more famous than John Snow's investigation of a neighborhood cholera outbreak in the St. James, Westminster, area of London in 1854. In this study Snow is assumed to have proven that cholera was water rather than airborne through a methodology that became, and to a great extent remains, central to the science and social science of disease studies. And yet, Snow's work did not satisfy most of his contemporaries who considered his proof of a solely waterborne cholera interesting but unconvincing. Uniquely, this paper asks whether the caution of Snow's contemporaries was reasonable, and secondly, whether Snow might have been more convincing within the science of the day. The answers significantly alter our understanding of this paradigmatic case. It does so in a manner offering insights both into the origins of nineteenth century disease analysis and more generally, the relation of mapping in the investigation of an outbreak of uncertain origin. The result has general relevance—pedagogically and practically—in epidemiology, medical geography, and public health.  相似文献   
5.
目的:观察尿常规、尿自动分析仪和尿沉渣对100例尿中有形成份检测的敏感性。方法:100例病人的尿标本分别进行干化学分析,尿沉渣镜检和尿常规镜检,根据检查结果与临床诊断作对比,了解其诊断的符合率。结果:三种方法红细胞,白细胞,管型检测均有差异(P<0.05),其中:干化学法和尿沉渣镜检法对RBC的检出率明显高于常规法(P<0.001),而干化学法与尿沉渣镜检法对RBC的检出无显著性差异(P>0.05),尿沉渣镜检对WBC的检出率高于常规镜检及干化学法(P<0.05),而常规镜检对WBC的检出率与干化学法无显著性差异(P>0.05),尿沉渣镜检和尿常规镜检对管型的检出有显著性差异(P<0.05),以尿沉渣的检出率为高,结论:尿沉渣检镜是三种方法中对尿有形成份检出最好的一种方法。  相似文献   
6.
7.
This paper is part of a systematic literature review and presents methodological issues within studies, investigating therapeutic applications of music in cancer patients. This review focuses on published international research from the USA, Canada, Australia and European countries using four electronic databases: PSYCHINFO, WEB OF SCIENCE, MEDLINE and SCIENCEDIRECT. Thirty-two papers were identified and each paper was coded in terms of sample type, basic research question, research design and methodological details, results and implications for future research. This paper addresses questions related to study design and methodology. It explores and discusses the relative advantages and disadvantages of various approaches.  相似文献   
8.
血清纤维结合蛋白的酶免疫检测法   总被引:2,自引:0,他引:2  
张超 《贵州医药》2006,30(5):414-416
目的建立血清纤维结合蛋白(Fn)含量的酶免疫分析(EIA)检测方法。方法利用现有Fn检测试剂盒建立Fn的EIA测定法,并对所建立的方法从灵敏度、精密度、特异性、重复性等方面进行方法学评价。结果该法灵敏度为11.69ml/L,线性范围为50~300mg/L,批内变异系数为 3.82%,批间变异系数为5.10%,回收率97.7%。肺结核组及正常对照组血清Fn含量分别为 (188.82±5.51)mg/L和(275.25±18.11)mg/L,两组间差异有显著性意义(P<0.01);肺结核稳定期患者血清Fn显著高于进展期及好转期(P<0.05)。结论该方法线性范围适宜,准确度、精密度较好,符合临床检验工作要求。  相似文献   
9.
SRTR Center-Specific Reporting Tools: Posttransplant Outcomes   总被引:3,自引:2,他引:1  
Measuring and monitoring performance—be it waiting list and posttransplant outcomes by a transplant center, or organ donation success by an organ procurement organization and its partnering hospitals—is an important component of ensuring good care for people with end-stage organ failure. Many parties have an interest in examining these outcomes, from patients and their families to payers such as insurance companies or the Centers for Medicare and Medicaid Services; from primary caregivers providing patient counseling to government agencies charged with protecting patients.
The Scientific Registry of Transplant Recipients produces regular, public reports on the performance of transplant centers and organ procurement organizations. This article explains the statistical tools used to prepare these reports, with a focus on graft survival and patient survival rates of transplant centers—especially the methods used to fairly and usefully compare outcomes of centers that serve different populations. The article concludes with a practical application of these statistics—their use in screening transplant center performance to identify centers that may need remedial action by the OPTN/UNOS Membership and Professional Standards Committee.  相似文献   
10.
弥散张量磁共振成像方法概述   总被引:1,自引:0,他引:1  
弥散张量成像(diffusion tensor imaging,DTI)是一种根据组织内水分子的弥散特性来探测有机体的微观结构和病理改变的核磁共振成像方法,目前已经成为临床评估和生命科学研究重要的工具。本文结合近年来的文献综述了弥散张量成像的基本原理,列举了目前常用的成像方法,分析了它们的优缺点以及用途,并对弥散张量成像的发展方向作了一些展望。  相似文献   
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