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81.
[目的/意义]深入探究和学习习近平的读书思想,把握其与读书相关的思想精髓与思想价值,进而影响和推动阅读型、学习型、书香型社会的建设和发展。[方法/过程]根据习近平关于读书的系列重要论述,结合其自身长期不辍的读书经历,以人们普遍关注的关于读书的3个基本问题:"为什么读书""怎样读书"和"读什么书"为纬度,系统研究和阐释习近平读书思想。[结果/结论]习近平读书思想的分析与把握,对指导全民读书活动的开展以及阅读推广活动的深入推进具有重要的意义。  相似文献   
82.
ABSTRACT

As the world is witnessing the epidemic of coronavirus disease 2019, emerging genetics and clinical pieces of evidence suggest a similar immunopathology to those of severe acute respiratory syndrome and Middle East respiratory syndrome. Staying at home to prevent the spread of the virus and consequently being largely inactive is associated with unintended consequences. These can actually enhance the infection risk and exacerbate poor health conditions including impaired immune function. Physical activity is a feasible way of improving health, particularly physical and mental health in a time of social isolation. However, people with certain health conditions in these circumstances may need a special physical activity programme in addition to any exercise they may already be performing via online programmes. This review aims to provide practical guidelines during the COVID-19 quarantine period. We suggest performing aerobic, resistance training, respiratory muscle training and yoga in the healthy, and in those with upper respiratory tract illness, patients with lower respiratory tract illness should be restricted to respiratory muscle training and yoga. In addition, vitamins D and C, omega-3 fatty acids, and regular consumption of fruit and vegetables might be considered as nutritional aids to support the immune system in those affected by COVID-19.  相似文献   
83.
ABSTRACT

Ankle sprains are the most common injury in regular badminton players and usually occur at the end of a match or training. The purpose of the present study was to examine the influence of fatigue produced by badminton practice on the lower limb biomechanics of badminton players. It was hypothesized that fatigue induces ankle kinematic and lower leg muscle activity changes which may increase the risk of ankle sprain. Ankle kinematics, ankle kinetics and muscles activities of 17 regular badminton players were recorded during lateral jumps before and after an intense badminton practice session. Post-fatigue, ankle inversion at foot strike and peak ankle inversion increased (+2.6°, p = 0.003 and +2.5°, p = 0.005, respectively). EMG pre-activation within 100 ms before foot landing significantly decreased after fatigue for soleus (?23.4%, p = 0.031), gastrocnemius lateralis (?12.2%, p = 0.035), gastrocnemius medialis (?23.3%, p = 0.047) and peroneus brevis (?17.4%, p = 0.036). These results demonstrate impaired biomechanics of badminton players when fatigue increases, which may cause a greater risk of experiencing an ankle sprain injury.  相似文献   
84.
‘A tribute to Dr J. Rogge’ aims to systematically review muscle activity and muscle fatigue during sustained submaximal quasi-isometric knee extension exercise (hiking) related to Olympic dinghy sailing as a tribute to Dr Rogge’s merits in the world of sports. Dr Jacques Rogge is not only the former President of the International Olympic Committee, he was also an orthopaedic surgeon and a keen sailor, competing at three Olympic Games. In 1972, in fulfilment of the requirements for the degree of Master in Sports Medicine, he was the first who studied a sailors’ muscle activity by means of invasive needle electromyography (EMG) during a specific sailing technique (hiking) on a self-constructed sailing ergometer. Hiking is a bilateral and multi-joint submaximal quasi-isometric movement which dinghy sailors use to optimize boat speed and to prevent the boat from capsizing. Large stresses are generated in the anterior muscles that cross the knee and hip joint, mainly employing the quadriceps at an intensity of 30–40% maximal voluntary contraction (MVC), sometimes exceeding 100% MVC. Better sailing level is partially determined by a lower rate of neuromuscular fatigue during hiking and for ≈60% predicted by a higher maximal isometric quadriceps strength. Although useful in exercise testing, prediction of hiking endurance capacity based on the changes in surface EMG in thigh and trunk muscles during a hiking maintenance task is not reliable. This could probably be explained by the varying exercise intensity and joint angles, and the great number of muscles and joints involved in hiking.

Highlights

  • Dr Jacques Rogge, former president of the International Olympic Committee and Olympic Finn sailor, was the first to study muscle activity during sailing using invasive needle EMG to obtain his Master degree in Sports Medicine at the Ghent University.

  • Hiking is a critical bilateral and multi-joint movement during dinghy racing, accounting for >60% of the total upwind leg time. Hiking generates large stresses in the anterior muscles that cross the knee and hip joint.

  • Hiking is considered as a quasi-isometric bilateral knee extension exercise. Muscle activity measurements during sailing, recorded by means of EMG, show a mean contraction intensity of 30-40% maximal voluntary contraction with peaks exceeding 100%.

  • Hiking performance is strongly related to the development of neuromuscular fatigue in the quadriceps muscle. Since maximal strength is an important determinant of neuromuscular fatigue during hiking, combined strength and endurance training should be incorporated in the training program of dinghy sailors.

  相似文献   
85.
摘要:目的:Nrf2是机体氧化还原平衡的主要调节因子,本研究试图探讨Nrf2在有氧运动训练中对小鼠骨骼肌抗氧化能力的作用。方法:8周龄野生C57BL/6J小鼠和Nrf2敲除小鼠40只,雌雄各半。进一步各为安静组和运动组,每组10只,共4组:分别为野生安静组(WC),野生运动组(WE),敲除安静组(KC)和敲除运动组(KE)。运动组进行4周运动强度为70%VO2max跑速的跑台运动,每周运动6 d,每天运动1 h。运动组最后一次运动后休息48 h脱颈处死,取小鼠后腿骨骼肌。RT-PCR测量Nrf2及Nrf2介导的抗氧化基因mRNA表达量;Western blot法测定骨骼肌Nrf2及抗氧化蛋白含量; GSH试剂盒测量GSH/GSSG比值。结果:1)在安静情况下,KC组和WC组相比,骨骼肌中GSR、NQO1、GCLc、GPX、HO-1和SOD2这6个抗氧化蛋白表达以及GSH/GSSG值没有显著性改变。 2)4周有氧运动训练之后,Nrf2敲除运动组的大部分抗氧化蛋白(CAT, NQO1-1, GCLc, HO-1 and SOD2)和GSH/GSSG值都要显著低于野生运动组。结论:4周70%VO2max强度的有氧运动训练,增加了成年Nrf2敲除和野生鼠骨骼肌抗氧化蛋白表达量和GSH/GSSG比值的差异,而在无训练安静情况下在两种鼠中这些指标的差异不大。说明Nrf2对有氧运动训练中骨骼肌的抗氧化反应起着非常重要的作用。  相似文献   
86.
摘要:实用主义体育是沐浴着美国实用主义哲学与实用主义教育学的基本思想,承继并改造欧洲自然主义体育的基本理念和内容发展而来。20世纪初传入我国后,促使我国的学校体育教学内容发生了一系列变化,这些变化在某种程度上,促进了我国学校体育的完善和发展,但同时也造成体育学科的严谨性、科学性和适用性受到损害。这种现象在当今的体育基础教育改革中亦时有隐现,致使我国的基础体育教育受到了一定的影响。为了准确、清晰地研究和把握实用主义体育的精神实质,对体育教育领域的价值和存在的问题,本研究以体育教学内容的选择为着眼点,采用文献资料法,深入分析了自然主义体育与实用主义体育的基本差异,实用主义体育教学内容的理论基础、源流和发展。在充分认识体育教学内容“实用性”基本含义的基础上,研究结论认为,追求体育教学内容“实用性”,首先强调以“体育教学内容”这一核心要素为本,尊重学生作为实用性的基本指向;其次,强调应认识并厘清体育的本体价值和工具价值,在此基础上,努力对体育教学内容本体价值追求的回归,实现对体育教学内容工具价值的理性“扬弃”。  相似文献   
87.
从文化“双核”理论的视角看,我国龙舟体育文化的传承内容及范式是龙舟体育文化人才培养工作的关键问题之一.运用文献研究、问卷调查、专家访问、数理统计与逻辑分析等方法,对我国龙舟体育文化的传承内容及范式进行了深入探讨.结果表明:我国龙舟体育文化传承的主要内容包括龙舟精神文化、龙舟竞渡文化、龙舟教育文化、龙舟娱乐文化、龙舟物质文化与龙舟经贸文化等六类亚文化及其它们所涵盖的二十种具象文化.而我国龙舟体育文化传承的基本范式可概括为基于血缘关系的宗族传承范式、基于自在自发的民间传承范式、基于政府促进的社会培养范式与基于学校领域的教育培养方式.廓清上述龙舟文化的传承内容及范式对于当下我国龙舟体育文化传承人才培养工作面临的难题破解具有重要价值.  相似文献   
88.
论文通过分析石定1980年-1990年之间的文学创作,认为石定的小说描摹出了上世纪末黔北农村变化的历程,刻画出黔北农民心灵变迁的轨迹。石定的作品雅致纯净、天然灵动,是一幅幅打下时代印迹的水墨丹青。  相似文献   
89.
[目的/意义]针对当前知识发现服务中存在的个性化程度不高和推荐效果不佳等问题,提出一种基于用户兴趣度量和内容分析的推荐算法。[方法/过程]文章通过特征词分布、LDA主题分布、引文结构网络三个维度构建学术资源模型,并通过对用户行为的度量,计算用户对其浏览学术资源的兴趣度,结合学术资源模型构建用户兴趣模型。将用户兴趣模型与学术资源模型匹配,计算其相似度,得到用户对每条学术资源的兴趣值,最后将兴趣值最高的TOP-N学术资源推荐给用户。[结果/结论]通过实验检验算法的有效性和推荐准确率,结果显示,本文从实时动态度量兴趣的角度,提出的推荐算法能较好地预测用户兴趣,推荐效果显著,为实现发现服务精准推荐提供思路。  相似文献   
90.
本文把视线聚焦在新媒体的媒体语境当中,以百度百家号为例,考察了新媒体用户在内容层面、认知层面和行为层面上的认知与使用模式。基于对百度百家号用户媒介认知与媒介使用情况的网络问卷调查数据,本研究从新媒体用户重点关注的文章类型、内容来源的关注度以及网络内容的信任度三个方面分析了新媒体用户的内容消费特征并提出了优化网络内容平台内容建设机制及信息扩散机制的策略与建议。在用户层面,需重点培养激活核心用户以提升内容生态的活跃度;在平台层面,需纳入优质内容资源,重视品牌建设。  相似文献   
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