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1.
The aims of this study were to assess the reliability and validity of three methods of bioelectrical impedance analysis (based on induction between the hand and foot, between one foot and the other foot and between one hand and the other hand) and the skinfold method, and to construct prediction equations for total body density by examining cross-validity in young Japanese adult males. The participants were 50 Japanese males aged 18-27 years (height 1.72 +/- 0.06 m, body mass 64.9 +/- 9.0 kg; mean +/- s), each of whom was measured twice using each of the four methods. Relative body fat based on underwater weighing was used as the criterion for validity. To construct prediction equations for body density, we used multiple regression analysis, whereby all possible combinations were examined. The reliability of all three bioelectrical impedance methods was high (R = 0.999). Three new prediction equations were constructed for the hand-foot method, foot-foot method and skinfold method. The cross-validity of the equations was guaranteed. The relative body fat calculated using the new equations did not differ from that based on the underwater weighing method.  相似文献   
2.
This study examined age-group corresponding relationships of the controlled force exertion based on sinusoidal and quasi-random waveforms in 175 right-handed male adults aged 20 to 86 years. The subjects were divided into 3 groups based on age-level: 53 young (mean age 24.6, SD?=?3.3 years), 71 middle aged (mean age 44.3, SD?=?8.7 years), and 51 elderly (mean age 69.3, SD?=?6.4 years). The participants matched their submaximal grip strength by the dominant hand to changing demand values displayed as either a sinusoidal or a quasi-random waveform appearing on the display of a personal computer. The quasi-random waveform was changed in π with amplitude and in π/2 with frequency (peak and mean frequency were 0.1 Hz in both waveforms). The participants performed the controlled force exertion test three times with a 1-min interval (one trial was 40 sec) after one practice trial using the dominant hand. The measurement order was randomly assigned. The total of the differences between the demand value and grip exertion value for 25 sec were used as an evaluation parameter. The coefficient of variance was almost the same range in all age groups in both waveforms (CVSW ?=?30.8–35.6, CVRW ?=?26.3–37.7), but the elderly group showed the highest value in the quasi-random waveform. Significant correlations were found among the sinusoidal and quasi-random waveforms in the young, middle-aged, and elderly groups, but significant differences were not found in the correlations among each age group. The controlled force exertion evaluation based on the sinusoidal and quasi-random waveform displays has a moderate relationship, and this relationship does not show age-level differences.  相似文献   
3.
This study examined age group and individual differences in controlled force exertion by emulating sinusoidal and quasi-random waveforms in 222 right-handed female adults aged 20 to 86 years. The subjects matched their submaximal grip strength by the dominant hand to changing demand values displayed as either a sinusoidal or a quasi-random waveform appearing on the display of a personal computer. A total of the differences between the demanded value and grip exertion value for 25 seconds was used as an evaluation parameter. The measurements showed a tendency to increase across the age groups in both waveforms. Significant second-order curve regressions were identified, but there was no significant difference in the increase rates of both waveforms. Analysis of variance showed non-significant differences among means of both waveforms in all age groups, and the differences between means in groups of participants over 50 and 20- to 24-year-olds increased in both waveforms. Individual differences were almost the same in both waveforms.  相似文献   
4.
The purpose of this study was to evaluate the efficacy of multi-capillary electrophoresis instrument in clinical laboratory. An automated clinical capillary electrophoresis system was evaluated for performing serum proteins electrophoresis and immuno-fixation electrophoresis by subtraction. In this study the performance of capillary electrophoresis was compared with the cellulose acetate membrane electrophoresis and agarose gel immunofixation electrophoresis for serum proteins. The results of capillary electrophoresis and cellulose acetate membrane electrophoresis were good (r=0.89∼0.97) for protein fractions and A/G ratio except for β-gobulin fraction (r=0.60). Both within-run and day to day precisions (CVs) of assay results for 5 main fractions and A/G ratio (n=10) were between 0.3∼6.3%. The reference ranges of serum protein fractions obtained from 200 healthy individuals by cellulose acetate membrane electrophoresis were almost equal to that of capillary electrophoresis except for α-1 globulin fraction. No significant difference of electropherograms between cellulose acetate electrophoresis and capillary electrophoresis was observed in the abnormal serum such as presence of bilirubin (<20mg/dl), hemoglobin (<300 mg/dl), lipid (Intralipos <1%) and samples from patients with acute phase response, liver injury, polyclonal hyper gammaglobulinemia or M-proteinemia. The method of capillary immuno-fixation electrophoresis by subtraction showed good agreement with agarose gel immunofixation electrophoresis by subtraction identifying 30 monoclonal gammmopathy patient samples.  相似文献   
5.
In this article, we address the choice of suitable instructional units that might serve as the basis for cross-cultural analyses of classroom practice. Our argument draws on analyses undertaken as part of the Learner's Perspective Study (LPS). The database comprised a three-camera video record of sequences of 10 consecutive lessons in each classroom, supplemented by post-lesson video-stimulated interviews with teachers and students: a total of over 180 videotaped lessons, over 50 teacher interviews and almost 400 student interviews. The results of these analyses challenge the suitability of the lesson as the unit of comparative analysis. In particular, the location of the lesson in the topic sequence is seen to be a key influence on the lesson's structure, critically affecting the teacher's deployment of the constituent activities that we have called ‘lesson events.’ The lesson event is proposed as an alternative unit of international comparative analysis of classroom practice.  相似文献   
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7.
In fixed order quantity systems,uncertainty in lead time is expressed as a set of scenarios with occurrence probabilities,and the mean and variance in demand distribution are supposed to be changeable according to a known pattern.A new concept of "dynamic robust optimal reorder point" is proposed in this paper and its value is calculated as a "robust optimal reorder point function with respect to reorder time".Two approaches were employed in determining the dynamic optimal reorder point.The first is a shortage rate satisfaction approach and the second is a backorder cost minimization approach.The former aims at finding the minimum value of reorder point at each reorder time which satisfies the condition that the cumulative distribution function (CDF) of shortage rate under a given set of scenarios in lead time is greater than or equal to a basic CDF of shortage rate predetermined by a decision-maker.In the latter approach,the CDF of closeness of reorder point is defined at each reorder time to express how close to the optimal reorder points under the set of scenarios,and the dynamic optimal reorder point is defined according to stochastic ordering.Some numerical examples demonstrate the features of these dynamic robust optimal reorder points.  相似文献   
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9.
This study aimed to examine the age and sex differences in controlled force exertion measured by the bar chart display in 207 males (age 42.1 ± 19.8 years) and 249 females (age 41.7 ± 19.1 years) aged 15 to 86 years. The subjects matched their submaximal grip strength to changing demand values, which appeared as a moving bar chart on the display of a personal computer. The subjects performed the controlled force exertion test using the dominant hand three times with 1-min intervals (one trial was 40 sec) after one practice trial. A total of the differences between the demand value and the grip exertion value for 25 sec was used as the evaluation parameter. The errors in controlled force exertion showed a right-skewed distribution in both sexes but showed a normal distribution after logarithmic transformation (males, W = .06; females, W = .74; p > .05). In addition, the errors in controlled force exertion tended to increase constantly with age in both sexes. Significant linear regressions were identified (r 2 males = .88, r 2 females = .81), but there was no significant difference in the increase rate of both sexes. The results of the analysis of variance and multiple comparisons showed insignificant sex differences among means, except for those in individuals older than 70 years; significant differences between means in the older than 40-year-old age group and the 20-year-old age group were found in both sexes. Individual differences were almost the same in both sexes (CVmales = 20.0~34.8, CVfemales = 17.7~36.2). Errors in controlled force exertion showed a nonsignificant sex difference and increased gradually with age in both sexes but increased remarkably with age after 40 years of age.  相似文献   
10.
The aims of this study were to assess the validity and reliability of body volume and percent body fat determined by sulphur hexafluoride dilution, using underwater weighing as the criterion method, and to determine the influence of the magnitude of body volume. Thirty-one healthy Japanese individuals aged 18-27 years (16 males: height 1.70 +/- 0.06 m, mass 64.8 +/- 7.7 kg; 15 females: height 1.60 +/- 0.05 m, mass 55.2 +/- 6.2 kg; mean +/- s) participated in the study. Sulphur hexafluoride dilution measures the concentration of sulphur hexafluoride gas in the chamber (BSF-200, Shimazu Corp.). Underwater weighing was performed five times using a weight scale (AD-6204, A&D) after residual volume had been determined (System9, Minato Medical Corp.). There were no significant differences in the mean between two trials for body volume, body density or percent body fat determined by sulphur hexafluoride dilution. The intra-class correlation coefficient of these variables ranged from 0.985 to 0.999. The results suggest that sulphur hexafluoride dilution is a reliable method for assessing body composition. There was no significant difference in body volume or percent body fat between sulphur hexafluoride dilution (males: 61.3 +/- 7.6 litres, 18.4 +/- 6.7%; females: 52.8 +/- 6.9 litres, 21.0 +/- 8.9%) and underwater weighing (males: 60.6 +/- 7.0 litres, 15.6 +/- 3.5%; females: 53.0 +/- 6.5 litres, 23.7 +/- 6.1%) and there was a high correlation between the two (r = 0.997, P < 0.05). A Bland-Altman plot of the difference between percent body fat estimated by underwater weighing and sulphur hexafluoride dilution versus average percent body fat by the two methods showed no systematic difference (mean difference = -0.12 +/- 6.6 kg). The upper and lower limits of agreement were 13.2% and -13.4%, respectively. Determination by sulphur hexafluoride dilution resulted in both over- and underestimations in body volume and the difference between the two body volumes (determined by underwater weighing and by sulphur hexafluoride dilution) was inversely proportional to the mean body volume by the two methods. This suggests that improvements need to be made to the device or to the technique to maintain a constant volume of sulphur hexafluoride in the chamber.  相似文献   
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