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141.
灸足三里、关元穴对运动大鼠肝组织自由基代谢的影响   总被引:1,自引:0,他引:1  
通过建立艾灸足三里、关元大鼠的力竭跑台训练实验模型,测定了大鼠肝组织的超氧化物歧化酶(SOD)的活性、丙二醛(MDA)的水平、过氧化氢酶(CAT)活性以及谷胱甘肽过氧化物酶(GSH-Px)活性。实验结果显示,艾灸足三里、关元穴后,大鼠跑台运动能力明显提高;肝组织SOD活性显著高于各自对照组;MDA含量显著低于各自对照组。说明艾灸足三里、关元穴具有较强的抗自由基损伤和抗脂质过氧化损伤的作用,可减轻运动所产生的内源性自由基对大鼠的伤害。另外,艾灸足三里、关元穴对大鼠肝细胞膜有保护作用,可减少组织酶的外泄。  相似文献   
142.
以方差分析和线性相关分析方法,探讨补充精氨酸和游泳训练对小鼠血NO(bNO)、血尿素氮(bBUN)和骨骼肌一氧化氮合酶(sNOS)的影响,篮球训练对大学生bNO、bBUN的影响以及小鼠/人肝脏尿素生成与NO合成之间的关系。结果表明:1)补充精氨酸对安静和训练小鼠NO和尿素生成均无显著影响;2)有氧训练使人/小鼠的NO和尿素生成均显著增加,且两者呈高度相关。结论:机体通过有效的自身调节机制,能够满足有氧运动下NO和尿素合成对Arg的需求,不需额外补充;肝脏尿素循环与外周NO合成是相互促进的,这也许是机体在有氧运动条件下对Arg、Cit需求与供应的自身调节机制,即:同肝脏与骨骼肌之间的葡萄糖—丙氨酸循环一样,肝脏与外周NO合成组织间可能存在着高效的“Cit—Arg cycle”。该结论需进一步实验证实。  相似文献   
143.
体育锻炼的选择对治疗焦虑的影响   总被引:4,自引:0,他引:4  
焦虑是一种常见的不良情绪体验 ,通过体育锻炼可以达到对焦虑的治疗作用。体育锻炼的各种特征 ,如活动类型、强度、持续时间等都会对焦虑的治疗效应产生重要影响。因此 ,必须具体问题具体分析 ,因人而异 ,不同的人选择不同的锻炼方法 ,才有可能使体育锻炼治疗焦虑取得最大的效果。  相似文献   
144.
设计三种实验模型,即力竭游泳运动模型、递增负荷游泳训练模型、BSO排空GSH模型,研究三种模型对大鼠心肌中原癌基因c-jun和c-fos mRNA表达的影响。结果发现力竭运动后训练力竭组、注射BSO力竭组、对照力竭组的大鼠心肌中c-jun mRNA表达量与相对应的训练安静组、注射BSO、对照安静组均增加,大鼠心肌中c-fos安静组mRNA表达量增加。BSO力竭组的c-fos mRNA表达量高于对照力竭组。训练力竭组与对照力竭组相比c-fos mRNA表达量没有明显变化。由上述实验结果推出,长时间力竭运动机体活性氧产生增加,c-jun mRNA和c-fos mRNA的表达量增加,进而激活转录因子AP-1。  相似文献   
145.
锌对力竭运动时大鼠肝脑组织自由基代谢的影响   总被引:13,自引:0,他引:13  
张平  李明学  李岚 《体育科学》2005,25(5):63-64
以大鼠力竭性运动为模型,观察锌对力竭运动时肝和脑组织中自由基代谢的影响。结果显示:力竭运动后即刻,肝、脑组织的MDA和SOD显著下降。补充锌能使力竭运动时肝、脑组织的MDA明显降低,阻止SOD下降,并使大鼠运动至力竭的时间稍有延长。提示,力竭运动使大鼠肝、脑组织中的自由基代谢加强。锌在大鼠肝、脑组织中具有很强的抗氧化作用,从而消除运动时产生的过量自由基。  相似文献   
146.
With the development of economy and the English learning reform in China,the role of English has increased than ever before.Dual language immersion(DLI)programs,as a new way to offer both languages and content instructions,will gradually take place of traditional English learning and become a new tendency in China.The attitudes of related groups toward the DLI programs are very important to its further development.This paper will first give a brief introduction to the current situation in China,and then analyze the attitude toward DLI programs,includingones of students,teachers and administrators,to find out problems existing in current DLI programs.  相似文献   
147.
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   
148.
Organizations face increasing pressure to implement artificial intelligence (AI) within a variety of business processes and functions. Many perceived benefits surround AI, but a considerable amount of trepidation also exists because of the potential of AI to replace human employees and dehumanize work. Questions regarding the future of work in the age of AI are particularly salient in pre-adoption organizations, before employees have the opportunity to gain direct experience with AI. To cope with this potentially stressful situation, employees engage in cognitive appraisal processes based on their own knowledge and personal use of AI. These pre-adoptive appraisals of AI influence both affective and cognitive attitudes, which in turn trigger behavioral responses that influence an organization’s ability to leverage AI successfully. Our survey of 363 Taiwanese employees shows that perceptions of AI’s operational and cognitive capabilities are positively related to affective and cognitive attitudes toward AI, while concerns regarding AI have a negative relationship with affective attitude only. Interaction effects of employee knowledge and affective attitude are also observed. This work’s main contribution lies in the development of an empirically-tested model of the potential impact of AI on organizations from an employee perspective in the pre-adoption phase. These results have practical implications for how organizations prepare for the arrival of this transformative technology.  相似文献   
149.
ABSTRACT

The length of telomeres is an objective measure of biologic ageing. This study evaluated the extent minutes of walking per week are associated with leukocyte telomere length (LTL) in a random sample of 5,823 U.S. adults. The investigation was cross-sectional and data were obtained from the National Health and Nutrition Examination Survey (NHANES). LTL was measured by the quantitative polymerase chain reaction method. Walking minutes was calculated from walking frequency and duration measures. Results showed that for each year of chronological age, telomeres were 15.6 base pairs shorter (P < 0.0001). With walking minutes and LTL treated as continuous variables, the relationship was quadratic, not linear (F = 11.2, P = 0.0023). With walking time divided into three categories, adults who performed ≥ 150 minutes of walking per week had longer telomeres than those who did no regular walking, and those who did some, but less than the recommendation (F = 5.0, P = 0.0137). Regular walkers were estimated to have a biologic ageing advantage associated with 6.5–7.6 years less biologic ageing compared to non-walkers, after adjusting for covariates. Additional investigations designed to study causality and the mechanisms associated with the walking and LTL relationship are needed.  相似文献   
150.
针对学生做了大量习题但收效却不大这种教学中常见的现象,分析了原因,并指出教师要通过引导学生“一题十想”,明晰解题思路,总结解题规律,实现习题效能的最大化。  相似文献   
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