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1.
BackgroundUsing a mobile phone while performing a postural and locomotor tasks is a common, daily situation. Conversing or sending messages (SMS) while walking account for a significant share of accidental injuries. Therefore, understanding the consequences of using a mobile phone on balance and walking is important, all the more so when these postural and locomotor tasks are aggravated by a disease.Research questionOur objective was to conduct a scoping review on the influence of a dual-task situation – generated by the use of mobile phone – on users' postural and/or locomotor tasks.MethodsThe literature search was conducted in English on PubMed/Medline and CINHAL databases, using keywords associated with postural and locomotor tasks and with the use of mobile phone. Study location, population, number of subjects, experimental design, types of phone use, evaluated postural-locomotor tasks and expected effects were then analyzed.Results and significance46 studies were included in this work, 24 of which came from North America. All studies compared postural and locomotor tasks with and without the use of a smartphone. Ten studies also compared at least 2 groups with different characteristics. Only 4 studies included pathological subjects. Various modalities were tested, and most studies focused on walking. Results show that the use of smartphones slows down movement and induces a systematic imbalance, except when listening to music. The dual task of "using the smartphone during a postural or locomotor tasks" induces systematic disturbances of balance and movement, which must be taken into account in the rehabilitation approach. Future studies will have to extend the knowledge regarding pathological situations.  相似文献   
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Immune defenses provide resistance against infectious disease that is critical to survival. But immune defenses are costly, and limited resources allocated to immunity are not available for other physiological or developmental processes. We propose a framework for explaining variation in patterns of investment in two important subsystems of anti-pathogen defense: innate (non-specific) and acquired (specific) immunity. The developmental costs of acquired immunity are high, but the costs of maintenance and activation are relatively low. Innate immunity imposes lower upfront developmental costs, but higher operating costs. Innate defenses are mobilized quickly and are effective against novel pathogens. Acquired responses are less effective against novel exposures, but more effective against secondary exposures due to immunological memory. Based on their distinct profiles of costs and effectiveness, we propose that the balance of investment in innate versus acquired immunity is variable, and that this balance is optimized in response to local ecological conditions early in development. Nutritional abundance, high pathogen exposure and low signals of extrinsic mortality risk during sensitive periods of immune development should all favor relatively higher levels of investment in acquired immunity. Undernutrition, low pathogen exposure, and high mortality risk should favor innate immune defenses. The hypothesis provides a framework for organizing prior empirical research on the impact of developmental environments on innate and acquired immunity, and suggests promising directions for future research in human ecological immunology.  相似文献   
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目的:调查河南省中华医学会临床神经电生理专科学会的现状及存在问题。探讨解决存在问题的措施。方法:采用分层抽样与整体抽样对84个医疗单位242人进行信访调查,并对资料完整的225人(92.97%)进行分析。结果:男60人,女165人。年龄平均32.8岁。本科学历15.6%,无学历6.6%。高级职称9.3%,无职称5.4%。已专业培训49.3%,未专业培训50.7%。结论:我省临床神经电生理专业发展迅速,但技术人员新,学历、职称偏低,且49.3%的人员未经正规专业培训,人才出现断层,发展后劲不足。因此,采取技术人员许可证制度——执证上岗,有计划的培养高素质的技术人员是当务之急。  相似文献   
5.
珠海市横琴岛嗜人按蚊生态习性研究   总被引:4,自引:2,他引:2  
目的:研究珠海市横琴岛嗜人按蚊的生态习性。方法:蚊媒调查方法。结果:横琴岛嗜人按蚊主要孳生于水质清凉、遮阴良好的淡水沟溪及有丰富水体的香蕉地和甘蔗地等。属人、牛血兼吸品种,趋吸人血比例为76、34%,吸血后外逸比例为92、77%,夜间吸血活动高峰在午夜后至次日清晨,全年高峰季节在8~10月。结论:该地嗜人按蚊有人、牛血兼吸,趋吸人血比例较大陆品种低,偏野栖,夜间吸血活动持续时间长,全年活动高峰季节长的生态特点。  相似文献   
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刘凌云  李强 《卫生软科学》2007,21(5):431-433
自组织理论不仅证实了物质自我运动、自我发展的科学原理,而且为我们认识研究各种事物的演化、发展提供了具有普遍意义的新思路和新方法。熟谙生命系统的自组织性,恰当运用医学思维模式,对于开拓诊疗思维、提高诊疗效果会提供有益尝试和多元选择。  相似文献   
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本文依据三种现代教育理论思想的有益启示,围绕医学高等专科学校课堂教学质量的提升问题,提出以加强教育理论思想研修为突破口,进而采取更新教育观念、狠抓移植应用和改进教法学法来有效提高医学高等专科学校课堂教学质量的新思路。  相似文献   
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从非演绎方法入手,从分析与综合、归纳与概括、类比与联想三个方面联系歌唱的思维过程,论述非演绎思维方法在歌唱过程中的运用。思维的非演绎方法贯穿于歌唱的全过程,它们之间存在着紧密的联系。掌握思维的非演绎方法对于歌唱水平的提高有积极的促进作用。  相似文献   
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《明天的医学向何处去》一文是王佑三同志应中国中医研究院、中西医结合研究会1990~2010年中医药研究的重大进展与突破预测研究课题组和中国人体科学学会之约所撰。本报征得作者同意稍加删节后发表,期望引起对“明天的医学”的关注。  相似文献   
10.
Objective. To illustrate the potential sensitivity of ecological associations between mortality and certain socioeconomic factors to different methods of age-adjustment.
Data Sources. Secondary analysis employing state-level data from several publicly available sources. Crude and age-adjusted mortality rates for 1990 are obtained from the U.S. Centers for Disease Control. The Gini coefficient for family income and percent of persons below the federal poverty line are from the U.S. Bureau of Labor Statistics. Putnam's (2000) Social Capital Index was downloaded from http://www.bowlingalone.com ; the Social Mistrust Index was calculated from responses to the General Social Survey, following the method described in Kawachi et al. (1997) . All other covariates are obtained from the U.S. Census Bureau.
Study Design. We use least squares regression to estimate the effect of several state-level socioeconomic factors on mortality rates. We examine whether these statistical associations are sensitive to the use of alternative methods of accounting for the different age composition of state populations. Following several previous studies, we present results for the case when only mortality rates are age-adjusted. We contrast these results with those obtained from regressions of crude mortality on age variables.
Principal Findings. Different age-adjustment methods can cause a change in the sign or statistical significance of the association between mortality and various socioeconomic factors. When age variables are included as regressors, we find no significant association between mortality and either income inequality, minority racial concentration, or social capital.
Conclusions. Ecological associations between certain socioeconomic factors and mortality may be extremely sensitive to different age-adjustment methods.  相似文献   
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