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排序方式: 共有269条查询结果,搜索用时 15 毫秒
1.
间歇性低氧训练对气体代谢影响的实验研究 总被引:6,自引:3,他引:3
间歇性低氧训练是 90年代初在俄罗斯率先发展的一种新的科学训练方法 ,在运动训练中发挥了积极有效的作用。笔者通过人体实验 ,探讨间歇性低氧训练对气体代谢及运动耐力的影响 ,为该训练方法在我国的推广应用提供必要的理论 ,实践依据。实验结果表明 :间歇性低氧训练可有效提高呼吸系统功能 ,提高气体代谢效率 ,促进运动能力提高 ,是一种科学有效的训练方法 相似文献
2.
低氧训练促进大鼠骨骼肌组织血管生成的体视学研究 总被引:2,自引:0,他引:2
为了研究低氧、训练及低氧训练对骨骼肌组织血管生成的不同作用,采用3×3析因设计试验,将健康雄性SD大鼠72只,随机分为9组,采用免疫组织化学及生物体视学方法,检测骨骼肌组织中微血管密度参数的改变,分析低氧和运动训练两种不同的处理因素对骨骼肌组织微血管体积密度、表面积密度、长度密度的单独效应、主效应及交互作用.结果表明:CD34可较好显示骨骼肌组织的微血管.低氧处理及运动训练对骨骼肌组织微血管体积密度、表面积密度、长度密度的主效应有差别,低氧处理、运动训练的单独效应中以超低氧处理、低氧训练的效应最强,并且低氧处理与训练方式两因素之间具有协同交互作用. 相似文献
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间歇性低氧训练、疲劳和恢复对H反射参数影响初探 总被引:2,自引:0,他引:2
目的:研究间歇性低氧训练(IHT),以及训练结束后的运动性疲劳与恢复过程对H反射各参数的影响.方法:用自制低氧混合气体,对8名短跑运动员进行每日10~11%O2的循环低氧刺激,持续两周,在IHT前后以及IHT之后的疲劳与恢复过程进行H反射各参数测试.结果:两周IHT训练前后M波振幅增加,H波潜伏期升高,差异具有显著性;疲劳后即刻H渡振幅下降,恢复期前三分钟H波振幅显著降低,随后逐渐恢复,在恢复期第15分钟,H波振幅显著升高.结论:H反射是敏感的反映低氧训练以及疲劳对短跑运动员神经系统的影响指标,并提示H反射低氧训练的改变以及运动性疲劳前后以及恢复期的变化与两周低氧训练引起的H反射通路脊髓水平的适应性有关. 相似文献
5.
Jon Bruschke Andrew Gonis III Sarah A. Hill Pam Fiber-Ostrow William Loges 《Communication monographs》2016,83(4):521-534
Prior research on pretrial publicity has produced mixed results and a roughly equal number of studies show an effect, show no effect, or show mixed results. We explored the effects of (a) homogenous vs. heterogeneous exposure (whether deliberating jurors were all exposed to the same publicity or not) and (b) pre-deliberation queries as potential contributors to mixed results. We found an effect for positive but not negative publicity on conviction rates but not evidence ratings. Exposure heterogeneity appears to explain these differences and pre-deliberation queries did appear to play some role in the obtained outcomes. Overall these findings do not replicate a robust publicity effect and future research should consider how homogeneous exposure and pre-deliberation opinion queries influence results. 相似文献
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Mary Anne Ullery Antonio Gonzalez Lynne Katz 《International Journal of Disability, Development & Education》2016,63(4):403-418
This study explores the long-term impact on participation in the Linda Ray Intervention Program (LRIP) for children (n = 54) who were developmentally delayed and prenatally exposed to cocaine. By identifying a group of programme graduates from a high crime/high poverty neighbourhood in Miami-Dade County using ArcGIS 10.2 software, a quasi-experimental design was used to compare children living in this area who participated in the centre-based modality (5 h a day; 5 days a week) to children living in this area who participated in the home-based modality (3 h per week) on their Florida Comprehensive Assessment Test (FCAT) reading and math scale scores in public school. The children who participated in the centre-based modality reported stronger outcomes in both math and reading FCAT scale scores at the p < .05 level and also out-performed their school-age peers on both math and reading FCAT scores at the p < .05 level. 相似文献
8.
Suneesh Kumar Pachathundikandi Earaly Thomas Varghese 《Indian journal of clinical biochemistry : IJCB》2006,21(2):114-117
Blood zinc protoporphyrin (ZPP), serum total protein (TP), and total cholesterol (TC) levels in automobile workshop workers
in relation to lead toxicity were analysed. In the present study, automobile workshop workers (healthy male workers at an
age between 28 and 35 from four major automobile workshops in Kottayam, Kerala State, India) and the control (male healthy
adults at an age between 28 and 35 residing at Aymanam, a distant village at Kottayam District, Kerala having reduced or no
chance of lead exposure) displayed significant difference in blood lead (BPb) and blood ZZP (BZPP) level. The mean value of
BPb in automobile workshop workers was 15.76±0.33 μg/dl, while in the control it was 8.20±0.15 μg/dl. In automobile workshop
workers, the mean value of BZPP was 34.2±0.62 μg/dl. The control group exhibited a mean of 11.5±0.22 μg/dl. Automobile workshop
workers exhibited significant increase in BZPP was corresponding to the increase in BPb level. The total protein levels estimated
in automobile workshop workers showed significant decrease compared to control individuals, but was within the reference range
of healthy individuals. The mean value of TP level in automobile workshop workers and control was 6.9±0.13 g/dl and 7.71±0.18
g/dl, respectively. There was no significant difference in blood haemoglobin (BHb) level among the automobile workshop workers
and control. The serum TC level in automobile workshop workers showed significant decrease compared to the control individuals,
but was with in the reference range of healthy individuals. The mean level of serum TC in automobile workshop workers was
162.00±3.44 mg/dl and the same in control was 172.86±4.32 mg/dl. The present study affirms occupational lead toxicity in automobile
workshop workers and its effect on serum protein and cholesterol levels. 相似文献
9.
武建国 《湖北广播电视大学学报》2011,31(5):89-90
在冰天雪地、滴水成冰的严寒深冬里,如何才能得到一幅完美的冰雪摄影佳作,关键是如何正确测光,如何正确曝光,这些都是决定拍摄成败的关键。 相似文献
10.