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1.
研究旨在探讨一次不同抗阻训练方案对外周血CD4+和CD8+T淋巴细胞亚群迁移和凋亡的影响。通过实验法15名无训练经历的健康青年男性分别进行一次以促进肌肉肥大(H-RT组,方案:70%1RM,10RM,3组,组间间歇1.5 min)和以改善肌肉耐力(E-RT组,方案:60%1RM,15RM,3组,组间间歇1 min)为目的的抗阻训练方案。并于训练前、训练后即刻、训练后2 h和24 h利用流式细胞仪测定表面标志物CX3CR1和annexin V表达量检测CD4+、CD8+T淋巴细胞亚群迁移和凋亡(用阳性表达率表示)。得出以下数据:(1)CD4+T细胞在H-RT组运动后即刻和运动后24 h,annexin V和CX3CR1阳性表达率显著性升高(P<0.05)。E-RT组annexin V阳性表达率在运动后即刻降低(P<0.05),24 h显著性升高(P<0.05);CX3CR1阳性表达率仅在运动后即刻升高(P<0.05)。(2)CD8+T细胞在H-RT组和E-RT组运动后即刻和运动后24 h,annexin V和CX3CR1阳性表达率均显著性升高(P<0.05)。通过对以上数据的分析,研究得出以下结论:CD4+T淋巴细胞亚群对于急性抗阻训练的免疫反应存在运动方案依赖性。  相似文献   
2.
Recent advances have enabled diagnostic classification models (DCMs) to accommodate longitudinal data. These longitudinal DCMs were developed to study how examinees change, or transition, between different attribute mastery statuses over time. This study examines using longitudinal DCMs as an approach to assessing growth and serves three purposes: (1) to define and evaluate two reliability measures to be used in the application of longitudinal DCMs; (2) through simulation, demonstrate that longitudinal DCM growth estimates have increased reliability compared to longitudinal item response theory models; and (3) through an empirical analysis, illustrate the practical and interpretive benefits of longitudinal DCMs. A discussion describes how longitudinal DCMs can be used as practical and reliable psychometric models when categorical and criterion‐referenced interpretations of growth are desired.  相似文献   
3.
BackgroundOne-hour postprandial hyperglycemia is associated with increased risk of type 2 diabetes and cardiovascular disease. Physical activity (PA) has short-term beneficial effects on post-meal glucose response. This study compared the oral glucose tolerance test results of 3 groups of people with habitually different levels of PA.MethodsThirty-one adults without diabetes (age 25.9 ± 6.6 years; body mass index 23.8 ± 3.8 kg/m2; mean ± SD) were recruited and divided into 3 groups based on self-reported PA volume and intensity: low activity < 30 min/day of moderate-intensity activity (n = 11), moderately active ≥ 30 min/day of moderate-intensity PA (n = 10), and very active ≥ 60 min/day of PA at high intensity (n = 10). Participants completed an oral glucose tolerance test (50 g glucose) with capillary blood samples obtained at baseline, 15 min, 30 min, 45 min, 60 min, 90 min, and 120 min post-ingestion.ResultsThere were no significant differences between groups for age or body fat percentage or glycated hemoglobin (p > 0.05). The groups were significantly different in terms of baseline glucose level (p = 0.003) and, marginally, for gender (p = 0.053) and BMI (p = 0.050). There was a statistically significant effect of PA on the 1-h postprandial glucose results (p = 0.029), with differences between very active and low activity groups (p = 0.008) but not between the moderately active and low activity groups (p = 0.360), even when baseline glucose level and gender differences were accounted for. For incremental area under the curve there was no significant effect of activity group once gender and body fat percentage had been accounted for (p = 0.401). Those in the low activity group took 15 min longer to reach peak glucose level than those in the very active group (p = 0.012).ConclusionThe results suggest that high levels of PA have a beneficial effect on postprandial blood glucose profiles when compared to low and moderate levels of activity.  相似文献   
4.
为探讨关键反应训练法对自闭症儿童主动提问技能的干预效果,采用单一被试研究中的跨行为多基线实验设计对一名自闭症儿童的物品主动提问、人物主动提问、地点主动提问等三个主动提问技能进行干预。研究结果表明关键反应训练法对自闭症儿童主动提问技能具有立即效果、维持效果和类化效果。为此,可以应用关键反应训练法对自闭症儿童进行训练。  相似文献   
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Historically, disaster response efforts have focused primarily on basic physical survival and safety—addressing medical emergencies and ensuring adequate shelter and supplies of food and water. However, in addition to physical survival, relief efforts must also consider strategies to promote emotional healing and psychological well-being. In particular, those who intervene must consider the acceptability of intervention strategies, taking into account survivors' cultural background, religious customs, and spiritual beliefs. This article offers recommendations to better align school-based therapeutic interventions with children's religious and spiritual beliefs.  相似文献   
7.
A polytomous item is one for which the responses are scored according to three or more categories. Given the increasing use of polytomous items in assessment practices, item response theory (IRT) models specialized for polytomous items are becoming increasingly common. The purpose of this ITEMS module is to provide an accessible overview of polytomous IRT models. The module presents commonly encountered polytomous IRT models, describes their properties, and contrasts their defining principles and assumptions. After completing this module, the reader should have a sound understating of what a polytomous IRT model is, the manner in which the equations of the models are generated from the model's underlying step functions, how widely used polytomous IRT models differ with respect to their definitional properties, and how to interpret the parameters of polytomous IRT models.  相似文献   
8.
Content‐based automated scoring has been applied in a variety of science domains. However, many prior applications involved simplified scoring rubrics without considering rubrics representing multiple levels of understanding. This study tested a concept‐based scoring tool for content‐based scoring, c‐rater?, for four science items with rubrics aiming to differentiate among multiple levels of understanding. The items showed moderate to good agreement with human scores. The findings suggest that automated scoring has the potential to score constructed‐response items with complex scoring rubrics, but in its current design cannot replace human raters. This article discusses sources of disagreement and factors that could potentially improve the accuracy of concept‐based automated scoring.  相似文献   
9.
美国次贷危机引发全球金融风暴,导致全球实体经济损失惨重,我国中小企业深受其害。后金融危机时代,我国中小企业,尤其外贸出口型和劳动密集型企业面临诸多发展困境,它们应提升决策管理地位,建立灵活应对市场变化的管理机制,研究和制定应对影响企业发展的有关法律制度,完善行业组织管理,以应对金融危机的影响。  相似文献   
10.
在辛亥革命时期,湖南因其特殊的历史机缘成为举足轻重的省区之一,具有重要的历史地位,如在国内率先发动的长沙起义、震惊中外的萍浏醴起义、社会广泛参与的湖南保路运动、声势浩大的长沙抢米风潮以及首先响应武昌首义、派遣湘军援鄂等都是辛亥革命史链条中的重要环节。而湘籍志士作为一个群体在整个辛亥革命运动中广泛开展舆论宣传、深入进行组织发动、拥戴和捍卫孙中山的领袖地位以及领导反清武装起义等方面都作出了不可磨灭的贡献。  相似文献   
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