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21.
通过访谈17位中小学教师对学生作业负担影响因素的理解,结果发现:大部分教师认为作业布置(作业类型、作业来源和是否允许有选择的做)、作业批改与反馈、课堂反馈和评价伦理(教师偏好)通过影响学生作业正确率、作业态度和心情,进而会影响学生的作业负担。针对这些发现,提出如下建议:分层设计多种类型的作业,有效减轻不同学生的作业负担;作业批改与反馈应关注描述性和时效性,改善学生后续作业的质量;课堂反馈应注重激励性,有效减轻学生的作业心理负担;营建和谐的师生关系,丰富学生积极的作业体验。 相似文献
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慢性肺源性心脏病是老年人的常见病、多发病,随着我国逐渐进入老龄化社会,肺心病失代偿期对老年人、对家庭、对社会的各方面影响将不断扩大。文章主要运用我国传统医学的理论阐述小寒、大寒季节对本病产生的影响,对疾病的发展及预后起着重要的临床指导作用。 相似文献
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Xiaochuan Zhang Xianzhen Yin Jingjing Zhang Anan Li Hui Gong Qingming Luo Haiyan Zhang Zhaobing Gao Hualiang Jiang 《国家科学评论(英文版)》2019,6(6):1223
Accumulating evidence indicates the critical importance of cerebrovascular dysfunction in the pathogenesis of Alzheimer''s disease (AD). However, systematic comparative studies on the precise brain vasculature of wild-type and AD model mice are still rare. Using an image-optimization method for analysing Micro-Optical Sectioning Tomography (MOST) data, we generated cross-scale whole-brain 3D atlases that cover the entire vascular system from large vessels down to smallest capillaries at submicron resolution, for both wild-type mice and a transgenic (APP/PS1) mouse model of AD. In addition to distinct vascular patterns in different brain regions, we found that the main vessels of the molecular layer of the hippocampal dentate gyrus (DG-ml) undergo abrupt changes in both diameter and branch angle, spreading a unique comb-like pattern of capillaries. By using a quantitative analysis workflow, we identified in the hippocampus of AD mice an overall reduction of the mean vascular diameter, volume fraction and branch angle, with most significant impairment in the DG-ml. In addition, virtual endoscopy revealed irregular morphological features in the vessel lumen of the AD mice, potentially contributing to the impairment of blood flow. Our results demonstrate the capability of high-resolution cross-scale evaluation of brain vasculature and underscore the importance of studying hippocampal microcirculation for understanding AD pathogenesis. 相似文献
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Kelly A. Mackintosh Nicola D. Ridgers Melitta A. McNarry 《Journal of sports sciences》2019,37(13):1506-1511
Physical activity (PA) is a key element in Cystic Fibrosis (CF) treatment strategies, yet little is known as to whether activity compensation occurs. This study examined whether PA and/or sedentary time on one day were temporally associated with time spent in these intensities the following day in youth with CF. Time spent sedentary and in different PA intensities were objectively-measured for seven consecutive days in 50 youth (22 boys; 12.0 ± 2.7 years); 25 with mild-to-moderate CF and 25 age- and sex-matched controls. Multilevel analyses (day and child) were conducted using generalised linear latent and mixed models. On any given day, every additional 10 minutes spent in sedentary time or moderate-to-vigorous physical activity (MVPA) were associated with 1.9 (95%CI: ?3.6 to ?1.2) and 12.4 (95%CI: ?22.1 to ?2.9) minutes less sedentary time the following day, respectively. These temporal associations were also observed when split by group (3.1 vs. 1.9 minutes for healthy and CF, respectively). These findings indicate that youth do not compensate their PA, irrespective of disease status, between days, but may compensate their sedentary time between days. Experimental studies are warranted to fully elucidate whether compensatory responses to PA and sedentary time occur, which is fundamental for informing PA promotion strategies. 相似文献
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Alis Bonsignore Shannon S. D. Bredin Holly Wollmann Barb Morrison Andrew Jeklin Lauren Buschmann 《European Journal of Sport Science》2017,17(4):441-446
There is inconclusive evidence concerning the effects of routine participation in ultra-endurance events on cardiovascular disease (CVD) risk. Arterial compliance is a reliable, non-invasive, and effective tool for evaluating CVD risk. The purpose of this research was to examine if race length influences acute changes in arterial compliance following an ultra-marathon event. A total of 46 ultra-marathon runners were recruited including 21 participants (39.8?±?8.3?years, 6 females) in the 80-km event and 25 participants (43.7?±?9.8?years, 3 female) in the 195-km event. Arterial compliance was measured via radial applanation tonometry (CR-2000, HDI) for diastolic pulse contour analysis before and following the race. Significant between-group differences were found for changes in large arterial compliance with a decrease (increase in stiffness) following the 195-km event and an increase following the 80-kilometre event (p?<?.05). Longer race lengths are associated with greater reductions in large arterial compliance following recreational ultra-marathon running. Assessment of arterial compliance might be a useful prognostic tool to assess the long-term risk of CVD among ultra-marathon runners. 相似文献
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摘要:心血管疾病(CVD)一直是全世界最主要的死因。由于CVD等慢性疾病对健康的威胁越来越大,有必要开展生活方式干预项目以控制这些疾病的危险因素。本研究的目的是评估美国的重要慢病干预项目—HELPS治疗型生活方式改变(TLC)项目对减少CVD危险因素和其他慢性疾病的有效性。方法:140位大学教职工参加为期12周的HELPS TLC项目,干预前后用配对t检验对其体重、BMI、腰围(WC)、6分钟步行距离(6MWD)、空腹血脂和血糖进行测定和比较。结果:干预后6MWD显著增加,总胆固醇(TC)和WC显著下降。对“高危”参与者进一步分析显示:BMI(-1.5±0.5,-3.9%)、TC(- 22.8±4.0,-9.0%)、LDL(- 14.1±4.9,9.3%)和血糖(-6.9±2.2,-6.1%)均显著下降;男性腰围(-4.5±0.8,-10%)显著减小,女性未见显著改变(-1.5±0.5,-4.0%)。此外,体重的变化与TC(r=0.43)、LDL(r=0.35)和血糖(r=0.44)的变化均显著相关。结论:参加12周的生活方式干预项目可以使CVD危险因素减少,特别是在CVD“高危”个体中。HELPS TLC项目的远期效果还待进一步深入研究。 相似文献
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【目的/意义】评价我国突发公共卫生事件疾控应急工作情报能力现状,识别肺炎鏖战中情报能力的问题,对指导现实工作具有重要意义。【方法/过程】本文以新型冠状病毒肺炎疫情为具体问题,推演疾控应急工作情报智慧树模型,设计因应的情报能力评价体系,改进熵权法来测定指标权重及评价结果。通过比较权重的位序与增量来发现疫情任务情报能力的重点,以及情报能力在该问题中和既往工作的差异,利用短板参量分析肺炎鏖战中情报能力的不足。【结果/结论】研究发现:本次任务对情报保障和利用能力具有较高要求,较与以往疾控应急工作,对情报加工和传递能力的需求加剧;情报决策、情报处理与分析、情报劳动者和情报政策成为疾控应急工作情报能力的重要因素;短板问题存在于应急队伍、开展应用性应急课题研究和应急情报管理机制之中,另有待优化问题存在于应急预案、公众引导、应急制度等项目之中。本研究根据上述分析结果对肺炎鏖战中的情报能力治理提出对策建议。 相似文献
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《西游记》第八回中观音为寻取经人,幻化模样后的人间形象是一个满身病疮的,衣衫褴褛的落魄和尚。在人们心目中法相庄严的观音怎么会幻化成这样一副模样?这绝不是信手拈来的自由发挥,而是有着文献依据的。通过一连串相互继连的记载可以考证出其源流。 相似文献