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排序方式: 共有217条查询结果,搜索用时 221 毫秒
1.
有氧运动对非酒精性脂肪性肝病身体成分和肝脏声像图的影响 总被引:3,自引:0,他引:3
为探讨有氧运动对非酒精性脂肪性肝病患者身体成分、肝脏声像图的干预效果,本研究将研究对象随机分为运动组和对照组,运动组采用个体化的运动处方进行为期12周有计划、有规律的运动锻炼,对照组不参加特殊运动,观察时间同治疗组.在实验前后分别测试两组研究对象的身体成分和肝脏B超检查.研究结果表明:运动组通过12周健步走有氧运动后,其身体成分指标(体重、体脂肪、体脂百分数、腰臀比、体重指数BMI)较运动前有显著性的下降(P<0.01);运动组肝脏B超检查结果显示总有效率明显高于对照组,两组相比在统计学上有显著性差异(P<0.01).实验结论:科学、规律、个体化的健步走有氧运动的实施对非酒精性脂肪性肝病起着积极、有效、重要的防治作用,值得在社区、临床上大力推广应用. 相似文献
2.
通过判读手掌和手腕骨的X光成像图片来评价青少年骨龄是体育和医学界一直使用的传统方法,长期的实践应用已证明它是行之有效的。但为变革其固有的缺陷对新的评价方法的探索一直没有停止,其中以色列阳光公司研制的BoneAge超声骨龄检测仪利用定量超声原理来评价骨龄,已批量投入市场且已为国内部分省市的体育部门所采用。研究目的:对BoneAge超声检测方法和传统X光拍摄方法进行方法学比较分析,检验新方法的准确性和有效性,以维护骨龄检测的权威性和科学性。研究对象:5-17岁男女青少年322名。研究方法:(1)超声骨龄仪的可重复性试验(实验对象93名);(2)X光片判读结果与超声检测结果的比较。对223名男女青少年拍摄手掌(腕)骨进行X光拍摄后随即使用BonAge超声骨龄检测仪对同批对象进行手腕部超声扫描。将超声骨龄结果与两位专家对X光片盲式读片结果的平均值进行比较分析。研究结果:(1)对超声骨龄仪的可重复性实验结果表明,两次测试的骨龄均值无显著性差异且呈高度相关,提示该仪器总体稳定性良好;(2)对超声骨龄结果与X光骨龄均值比较的显示,无论是区分年龄段还是性别,两种评定结果之间均有较大的系统误差和随机误差,且这种误差随年龄段的增大而有所加大;对年龄段较高的人群,超声检测结果更易高估对象的骨发育程度;单因变量多因素方差分析表明,骨龄评价结果主要受到评定方法和年龄段因素的影响,而与性别因素关系不大;对超声骨龄和X光骨龄的相关程度和直线回归分析表明,尽管总体人群的两种评价结果存在高度相关,直线回归效果较好,但引入年龄段因素后,相关程度明显降低,回归效果较差,提示这两种方法之间不能相互替代。 相似文献
3.
Kristina L. Kendall David H. Fukuda Parker N. Hyde Abbie E. Smith-Ryan Jordon R. Moon Jeffrey R. Stout 《Journal of sports sciences》2017,35(7):624-633
The purpose of this study was to investigate the accuracy of fat-free mass (FFM) estimates from two-compartment (2C) models including air displacement plethysmography (ADP), ultrasound (US), near-infrared interactance (NIR), and the Jackson and Pollock skinfold equation (SKF) against a criterion four-compartment (4C) model in elite male rowers. METHODS: Twenty-three elite-level male rowers (mean± SD; age 24.6 ± 2.2 years; stature: 191.4 ± 7.2 cm; mass: 87.2 ± 11.2 kg) participated in this investigation. All body composition assessments were performed on the same day in random order, except for hydrostatic weighing (HW), which was measured last. FFM was evaluated using a 4C model, which included total body water from bioimpedance spectroscopy, body volume from HW, and total body bone mineral via dual-energy X-ray absorptiometry. The major findings of the study were that the 2C models evaluated overestimated FFM and should be considered with caution for the assessment of FFM in elite male rowers. Future studies should use multiple-compartment models, with measurement of TBW and bone mineral content, for the estimation of FFM. 相似文献
4.
据国际上的最新研究成果 ,论述了在全球环境变化引起的UV -B辐射过程中 ,植物对UV -B信号的感受和传导机理 ,其中包括细胞中UV -B信号受体 ,各种信号分子 (诸如活性氧、水杨酸、茉莉酸、乙烯和一氧化氮等 )的级联放大传递以及对于基因表达活性的影响 ,提出了UV -B胁迫信号传递的信号分子级联模型 ,从而为有效防护环境变化引起的UV -B辐射增强对于植物体的伤害提供理论依据 相似文献
5.
在微波辐射条件下,以氨基胍重碳酸盐和甲酸为原料合成了3-氨基-1,2,4-三氮唑,反应速度比传统加热条件提高300倍,产率达到83.5%。优化后的最佳反应条件为微波输出功率为120 W,氨基胍重碳酸盐:甲酸摩尔比为1:1.25,溶剂无水乙醇为5mL,反应时间为60 s。 相似文献
6.
B.M. Thompson K.P. Ribera G.J. Wingenbach T.A. Vestal 《Journal of Food Science Education》2007,6(2):24-29
ABSTRACT: The purpose of this study was to use a validated instrument to determine the attitudes and knowledge of high school teachers regarding food irradiation, and to determine the correlations among their knowledge and attitudes and certain demographic variables. Knowledge and attitudes about food irradiation were measured in selected high school family and consumer sciences teachers ( n = 121) who taught Food and Nutrition, Food Science and Technology, and/or Food Production Management and Services, via a 24-item instrument with 6 factors. Results revealed these teachers held neutral to positive attitudes about the safety of irradiated foods, their perception of the risk of foodborne illness, and learning about food irradiation, and neutral to negative perceptions of their understanding of food irradiation and their competence to teach about it. These teachers had a moderate knowledge base regarding food irradiation. Teachers' attitudes regarding the safety of food irradiation were positively correlated with their perceived understanding of food irradiation, actual knowledge of it, and competence to teach about it. Their perceived understanding of food irradiation was positively correlated with competence to teach about it, knowledge, and attitudes toward the safety of food irradiation. The only demographic variable correlated with knowledge or attitudes was teachers' previous food irradiation educational experiences. These data suggest the importance of education for family and consumer sciences teachers concerning food irradiation. 相似文献
7.
微波合成半导体HgS纳米粒子 总被引:2,自引:3,他引:2
廖学红 《黄冈师范学院学报》2001,21(3):48-51
在甲醛溶液中,以Hg(Ac)2和TAA为原材料,通过微波加热合成了HgS半导体纳米粒子,并用XRD、TEM、紫外光谱进行了表征。 相似文献
8.
辐照板鸭产生异味的初步研究 总被引:1,自引:0,他引:1
采用辐射贮存肉类,剂量较高时会产生辐射异味.研究表明:板鸭辐射味随剂量的增加而加强,当剂量超过5kGy时,即引起较强的辐射味.辐射味主要来源于板鸭肌肉蛋白,特别是其中的水溶性蛋白质部分;辐射味与羰基化合物、挥发性含硫化合物及胺等有关,其含量随剂量的加大而增加.辐射产生了两种新羰基化合物(R_f值分别为0.23和0.28)及一种挥发性胺——丙胺. 相似文献
9.
10.
In order to carry out decolorization, sludge protein solution, a dark brown close to black solution from activated sludge, was subjected to 60Co γ-ray irradiation in the presence of hydrogen peroxide. UV/Vis spectrophotometric method was used to investigate the effect of H2O2 on the coloration apparent kinetics and rate constants of sludge protein solution under γ-ray irradiation. In addition, the effects of irradiation dose, initial sludge protein solution concentration, and pH value on the decolorization efficiency of sludge protein solution were studied. Results showed that the decolorization apparent kinetics of sludge protein solution was a first-order reaction. The solution decolorization percentage increased with the increase of irradiation dose or the decrease of initial sludge protein solution concentration. The examination results of pH value showed that the sludge protein solution could be more efficiently decolorized in alkaline media than in acid media. Moreover, sensory evaluation and foamability analysis indicated that irradiated samples under H2O2 oxidation showed better sensory score and foamability. 相似文献