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1.
目的:研究运动员稀氧区域训练对肌肉纤维耐久力的影响。方法:分析18名运动员在常氧和高原低氧(模拟海拔4500 m递增负荷运动时,低氧通气反应速率、最大摄氧量以及最大耐力持续时间三个肌肉纤维耐久力评估指标的变化情况。结果:高原低氧训练时运动员低氧通气速率和最大耐力持续时间显著高于常氧对应值,高原低氧训练时,运动员最大摄氧量低于常氧对照组。高原低氧训练组,运动员在4个不同功率等级低氧通气速率,均高于常氧对应值,低氧通气速率在50%、75%以及100%最大功率时显著高于常氧对应值,最大摄氧量在各相对功率等级中,无显著性差异。运动员的低氧通气反应速率在高原低氧训练组至75%最大功率阶段降低,在75%至100%最大功率阶段基本保持平稳上升,不同相对强度下低氧训练组运动员最大摄氧量较常氧对应值显著降低。结论:高原运动训练下运动员肌肉纤维耐久力增强,疲劳时间降低,可提高运动员的运动能力。 相似文献
2.
目的:研究氧气稀缺区的运动强度同内脏损伤关系。方法:选择某大学竞技体育学院运动员30名,受试者分别在常氧、模拟海拔1500、2500、3500 m低氧环境中,完成传递负荷功率自行车测试,探讨运动员最大摄氧量以及运动强度同内脏损伤的关系。结果:随着海拔高度的增加,运动心率呈现下降趋势;低氧环境下运动出现单峰值时,发生概率为50%的内脏轻度、中度和重度损伤的运动峰值,分别是66 N/次、116 N/次和180 N/次;随着运动强度的增加,引起同样程度运动强度所需的超强峰值逐渐降低。结论:低氧环境下,运动强度对人员内脏损伤的程度,主要同运动员最大摄氧量比例值,运动强度的峰值,运动持续时间有关,运动员最大摄氧量比例值越高,内脏损伤程度越低,运动强度峰值越高,内脏损伤的程度越高,运动持续时间越长,内脏损伤所需的运动强度值越低。 相似文献
3.
《科技通报》2015,(9)
目的:分析肥胖儿童下肢运动中的异常运动特征。方法:以某市某小学的30名学生为研究对象,将受试者划分为肥胖组和对照组,受试者以一定的角速度完成屈伸运动,各关节进行6次屈伸运动。对所有受试者每个关节最大峰力矩与最大相对峰力矩进行记录及统计。依据Cleveland Clinic法放置反光标记球。实验时要求受试者进行15s静态捕捉,及7个正常步速的步态周期。摄像机采集反光标记球,再利用Vicon Nexus 1.7.1完成自主测量及数据分析,通过Vicon Body Builder求出关节力矩,完成运动学和动力学分析。结果:运动前后肥胖组的身高、体重、BMI均无显著性差异。运动后,肥胖组伸膝绝对肌力、伸膝相对肌力、屈膝相对肌力明显增加,有显著性差异;屈膝绝对肌力、踝背屈绝对肌力、踝趾屈绝对肌力、踝背屈相对肌力、踝趾屈相对肌力非常显著性增加。对照组伸膝绝对肌力及相对肌力均非常显著性下降。肥胖组运动后步幅时间显著下降、步速显著增加,具有统计学意义;对照组运动后步幅时间显著增加,具有统计学意义。运动后肥胖组的髋关节在矢状面活动范围增加,有显著性差异;膝关节在矢状面活动范围降低,有非常显著性差异。肥胖组运动后髋关节的屈力矩增加,有显著性差异。和对照组相比变化值差异有统计学意义。结论:肥胖儿童下肢运动中的异常运动均有所改善。 相似文献
4.
目的：探讨＂高住低练＂对大鼠骨骼肌SDH和CCO的影响。方法：将8周龄SD雄性大鼠72只分为4组,常氧对照组（C）、常氧训练组（S）、高住对照组（H）和高住低练组（HS）,训练组每周训练3次,逐周递增负荷,共运动4周;实验结束时取大鼠心肌测定SDH和CCO活性。结果：安静状态的C组、S组、H组大鼠骨骼肌中SDH和CCO均有非常显著性差异（P〈0.01）,HS组和C组、S组、H组的SDH均有差异（P〈0.01）,H组、HS组和C组的CCO有差异（P 相似文献
5.
目的:分析高海拔运动下负载量同内分泌紊乱关系。方法:通过低压低氧舱模拟海拔5000 m高原低氧环境复制动物模型,将小鼠划分成常氧对照组以及低氧组:低负载量、中负载量以及高负载量组。测定小鼠血清游离三碘甲腺原氨酸FT3和促甲状腺激素FT3水平,分析高海拔运动下负载量逐渐增加过程中小鼠内分泌指标变、小鼠血浆中雌二醇水平,小鼠身体做功能力以及最大耗氧量情况。结果:随着低氧运动负载量的不断增加,低氧运动组小鼠体重都显著低于对照组,与常氧对照组对比,低氧运动的血清果酮下降(P0.05),低氧中负载运动(P0.01)和低氧高负载运动(P0.05)血清皮质醇呈现下降趋势,T/C在低氧低、中、高负载量(P0.05、P0.01、P0.05)较常氧对照组显著升高,低氧运动组小鼠血清下丘脑-垂体-游离三碘甲腺原氨酸FT3和促甲状腺激素TSH不断降低,并且运动负载量越大,小鼠FT3和TSH越低,运动后小鼠血浆雌二醇水平均较运动前显著降低(P0.01或P0.05)并且随着运动负载量的增加,低氧运动组小鼠的血浆雌二醇水平呈现下降趋势。小鼠机体出现适应变化、机体做功能力以及最大耗氧量都降低。结论:说明高海拔低氧运动下,运动员的运动负载量越高,其机体内分泌各指标值越低,内分泌系统活力大大降低,小鼠内分泌的紊乱程度增大,使得小鼠机体功能大大减弱。 相似文献
6.
目的:分析大鼠超负荷运动下心律紊乱规律。方法:按照不同摄氧量,将80只实验大鼠随机分为4组,并对大鼠的最大耗氧量、1min心率、呼吸频率以及心脏结蛋白的基因表达等指标进行检测。结果:在超负荷跑台运动中,受试大鼠心律在现低、中、高负荷时偏低,而最大负荷时偏高,中、高负荷及最大负荷运动时心率值同对照组存在显著差异(P0.05)。在恒定负荷运动中,大鼠的心律值整体偏低。运动组大鼠心律、呼吸频率、呼吸商以及摄氧量等指标相关系数远远低于对照组。不同强度负荷运动后,大鼠窦房结结蛋白mRNA表达量基本一致,但60%摄氧量运动下大鼠窦房结结蛋白mRNA表达量明显下降(P0.05)。超负荷运动后,大鼠房室结结蛋白mRNA表达量基本一致,但60%最大摄氧量超负荷运动下大鼠后房室结结蛋白mRNA表达量出现显著下降趋势(P0.05。结论:大鼠超负荷运动可导致心脏结蛋白受损,心律紊乱程度加强。 相似文献
7.
8.
目的:研究磷酸化活对高原缺氧负重训练动脉供血调控促进模型,促进运动员的心肺功能,提高运动员的供血调控水平。方法:通过高原缺氧负重训练,产生大量的磷酸化活物,人体中的磷酸化活物重组质粒p ET-28a-Agr C在C43(DE3)中表达为末端苏氨酸物体,通过提取人体内的血液标本,进行样本测试,对采集的运动员血液样本进行蛋白脂质体先用膜不可渗透硫醇-非荧光试剂(4-acetamido-4'-maleidylstibene-2,2'-disulphonic acid,Amdi S)标记,得到采用磷酸化活测定分析高原缺氧负重训练下的动脉供血调控促进模型结构。结果:运动员心率HR和肺活量VC显著性差异P0.01,缺氧负重训练中最大摄氧量VO2max的值都要大于台阶实验数值,达到最大摄氧量VO2max,心率HR的显著性差异P0.01。得到的测试组TG的心肺功能由于对比组CG1和CG2的显著差异性,进而促进动脉供血调控。结论:采用磷酸化活测定方法对高原缺氧负重训练动脉供血调控促进模型进行分析建模,对促进运动员的心肺功能,提高运动员的供血调控水平具有帮助。 相似文献
9.
《科技通报》2017,(10)
目的:研究长期高强度有氧训练对雄性大鼠跟腱粘弹性的影响。方法:选择雄性大鼠80只作为研究对象,随机将其划分成一次性跑台运动对照组、一次性跑台运动组、长期运动组和长期运动对照组,按照分组进行相应的训练。结果:一次性跑台运动对照组大鼠跟键组织主要由按顺应力方向排列整齐、结构致密的胶原纤维组成,胶原原纤维存在典型周期性横纹。一次性跑台运动组大鼠跟键局部胶原纤维之间的间隔变大,局部排列错乱。长期运动组大鼠跟腱组织胶原纤维排列较规则,粗细均匀,胶原纤维排列紧密。长期运动对照组大鼠胶原纤维排列紊乱,粗细不均,有部分出现断裂,胶原纤维较少。长期运动组大鼠刚度和最大载荷非常显著性高于长期运动对照组大鼠(P0.01),能量吸收显著高于长期运动对照组大鼠(P0.05)。一次性跑台运动组与一次性跑台运动对照组跟腱水含量、跟腱重量、羟脯氨酸无显著性差异(P0.05);长期运动组大鼠跟腱水含量、跟腱重量、羟脯氨酸与长期运动对照组大鼠相比无显著性差异(P0.05)。一次性跑台运动组PⅠNP显著高于一次性跑台运动对照组(P0.05),PⅢNP非常显著性高于一次性跑台运动对照组(P0.01)。长期运动组PⅠNP和colⅠα1非常显著性高于长期运动对照组(P0.01)。结论:长期高强度有氧训练能够增强雄性大鼠跟腱粘弹性。 相似文献
10.
《科技通报》2015,(12)
目的:研究运动焦虑对运动员的相关生理指标影响分析,并进行数学模型构建,实现定量分析,准确分析运动焦虑对运动员身体健康指标的制约因素,并进行科学指导。方法:采用流式细胞方式对抗原体表面的CXCR3进行受体分析,得到不同组中的纤维细胞表面的RNA浓度为10 mol/L,取0.4 m L金磁微粒于离心管中磁性分离,弃上清,用0.5 m L的偶联缓冲液(20 mmol/L,p H7.4)清洗,引入运动焦虑的蛋白脂质体的自我磷酸化活性检测,评价蛋白脂质体的功能稳定性,实现运动焦虑对运动员相关生理指标影响建模分析。结果:训练中最大摄氧量VO2max的值都要大于台阶实验数值,达到最大摄氧量VO2max,DP,PP,MAP的显著性差异P0.05,运动状态下,使得人体血动脉的血红蛋白和脂质体共存于组分,促进人体耐运动焦虑的末端苏氨酸物体的生成。血蛋白和脂质体在组分3内的最大回收率分别为80%和90%。结论:运动焦虑对运动员的生理指标有较大影响,采用本文方法进行焦虑调节,促进运动员的耐力水平和身体机能,缓解运动焦虑症状,提高运动锻炼的积极性和有效性。 相似文献
11.
Marjorie Armstrong-Stassen Margaret Landstrom Ramona Lumpkin 《The Information Society》1998,14(2):153-164
This study examined how students who had no prior experience with videoconferencing would react to the use of videoconferencing as an instructional medium. Students enrolled in seven different courses completed a questionnaire at the beginning of the semester and again at the end of the semester. Students at the origination and remote sites did not differ in their reactions toward videoconferencing but there was a significant difference for gender. Women reacted less favorably to videoconferencing. Compared to the beginning of the semester, students reported significantly less positive attitudes toward taking a course through videoconferencing at the end of the semester. There were no significant differences in students' attitudes toward videoconferencing across courses at the beginning of the semester but there were significant differences across the courses at the end of the semester. The results suggest the need for better preparation for both students and instructors. 相似文献
12.
A joint study by Prof. ZHANG Zhibin from the CAS Institute of Zoology his co-workers from Norway US Swiss have indicated that historical outbreaks of migratory locusts in China were associated with cold spells suggesting that China's projected climate warming could decrease the pest's numbers. The study was published in Proceedings of the National Academy of Sciences on September .…… 《中国科学院院刊(英文版)》2008,22(1):6-7
Ajoint study by Prof. ZHANG Zhibin from the CAS Institute of Zoology and his co-workers from Norway, US and Swiss have indicated that historical outbreaks of migratory locusts in China were associated with cold spells, suggesting that China＇s projected climate warming could decrease the pest＇s numbers. The study was published in Proceedings of theNational Academy of Sciences on 17 September, 2007. 相似文献
13.
Caroline Haythornthwaite 《The Information Society》2001,17(3):211-226
A computer-mediated group is a complex entity whose members exchange many types of information via multiple means of communication in pursuit of goals specific to their environment. Over time, they coordinate technical features of media with locally enacted use to achieve a viable working arrangement. To explore this complex interaction, a case study is presented of the social networks of interactions and media use among members of a class of computer-supported distance learners. Results show how group structures associated with project teams dominated who communicated with whom, about what, and via which media over the term, and how media came to occupy their own communication niches: Webboard for diffuse class-wide communication; Internet Relay Chat more to named others but still for general communication across the class; and e-mail primarily for intrateam communication. Face-to-face interaction, occurring only during a short on-campus session, appears to have had a catalytic effect on social and emotional exchanges. Results suggest the need to structure exchanges to balance class-wide sharing of ideas with subgroup interactions that facilitate project completion, and to provide media that support these two modes of interaction. 相似文献
14.
Electronic data interchange (EDI) provides means for interorganizational communication, creates network externalities, requires an advanced information technology (IT) infrastructure, and relies on standards. In the diffusion of such innovations, institutional involvement is imperative. Such institutions contain governmental agencies, national and global standardization organizations, local government, and nonprofit private organizations like industry associations. The last type of organizations we call intermediating institutions. They intermediate or coordinate ("inscribe") the activities of a group of would-be adopters. Unfortunately, little is known of how these organizations shape the EDI diffusion trajectory. In this article we examine one specific type of intermediating organizations?industry associations?and how they advanced the EDI diffusion process in the grocery sectors of Hong Kong, Denmark and Finland. We identify six institutional measures, placed into a matrix formed by the mode of involvement (influence vs. regulation) and the type of diffusion force (supply push vs. demand pull), that can be mobilized to further the EDI diffusion. Industry associations were found to be active users of all these measures to varying degrees. Their role was critical especially in knowledge building, knowledge deployment, and standard setting. Furthermore, institutional involvement varied due to policy and cultural contingencies and power dependencies. 相似文献
15.
Puay Tang 《The Information Society》1998,14(1):19-31
The increasing prospects of digital piracy has prompted the perceived need by electronic publishers to adopt technical systems of protection, and governments to reform their copyright laws. This article is a preliminary study of the management of intellectual property by electronic publishers, defined as those involved in the production of online databases, and CD-ROMs. It focuses on three main issues: (1) how electronic publishers view the increasing threat of piracy; (2) the methods of protection employed to protect intellectual property in digital format; and (3) the importance of technological protection of intellectual property in electronic publications. The analysis is based on a sample of 23 UK electronic publishers. The interviews revealed an interesting assortment of protection methods and did not show that technological protection was a preferred way. Instead, the means of protection, in addition to copyright law, comprised niche markets, pricing, trust, bad publicity, and nontechnical and technical means. 相似文献
16.
Milton Mueller 《The Information Society》2001,17(3):151-163
Long-standing conflict between domain name registrants and trademark holders prompted the Internet Corporation for Assigned Names and Numbers (ICANN) to create a global, mandatory arbitration procedure known as the Uniform Dispute Resolution Policy (UDRP). The UDRP has been used in 2166 cases involving 3938 domain names as of 1 November 2000. The policy gives the initiator of a complaint, generally a trademark holder, the right to choose which ICANN-accredited dispute resolution service provider (RSP) will handle the case. During the preparation of the UDRP,some feared that complainant selection would lead to "forum shopping" that might bias the results. This article performs a statistical assessment of the forum-shopping thesis and finds support for it. There are statistically significant differences in the various RSPs' propensity to take away names from defendants; there are also major differences in the number of cases brought to each RSP. RSPs who take away names have the larger share of cases. The study examines other variables that might explain differences in market share, such as price, the plaintiff's nationality, or the time taken to decide a case. It finds that nationality and time also are correlated with market share. The study concludes that shopping for a favorable outcome is an important factor in the UDRP. 相似文献
17.
Prof. Raymond C.K. Chen a neuropsychologist with the CAS Institute of Psychology has made novel progress in his studies of schizophrenia. His work has been reported by a recent issue of Behavioural Neurology.…… 《中国科学院院刊(英文版)》2008,22(1):15-15
Prof. Raymond C.K. Chen, a neuropsychologist with the CAS Institute of Psychology, has made novel progress in his studies of schizophrenia. His work has been reported by a recent issue of Behavioural Neurology. 相似文献
18.
《中国科学院院刊(英文版)》2014,(3)
<正>In Xishuangbanna,one of China’s most biodiverse regions,landscape has changed dramatically during the past three decades due to the conversion of tropical rainforest to rubber plantations.In steep areas,terraces are often constructed before planting rubber trees,which causes two important changes in the soil:the destabilization of soil in the bench terraces and the increased vulnerability of unvegetated riser faces to erosion.Few studies have documented the nature and intensity of erosion on bench terraces.Prof.LIU Wenjie and his colleagues from the Xishuangbanna Tropical Botanical Garden(XTBG)conducted a study in Menglun County(21°5′39″N,101°15′55″E),Xishuangbanna to evaluate the influence 相似文献
19.
Chinese Scientists Use Earth Observation Technologies to Study and Protect Wild Camels 总被引：1，自引：0，他引：1
《中国科学院院刊(英文版)》2014,(3):267-268
<正>Chinese scientists plan to apply Earth Observation technologies to protect the critically endangered wild camels(Camelus ferus).With the help of remote sensing,satellite positioning,geographical information system and wireless sensors networks,they will be able to access the distribution and population of the wild camels and protect their habitats.The project will be carried out by the International Research Center for Wild Camel Conservation,which was jointly established earlier this year by the Institute of Remote Sensing and Digital Earth(RADI)of the Chinese 相似文献
20.
WANG Sijia 《中国科学院院刊(英文版)》2014,(2):192-194
<正>The Paul Gerson Unna Research Group on Dermatogenomics was founded in October 2012 at the Partner Institute for Computational Biology.The ultimate goal of the group is to understand the biology of skin and skin appendages. 相似文献