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1.
Abstract

With cardiovascular fitness (CVF) as the dependent variable, relationships with habitual level of physical activity, age, gender, and body mass index (BMI) were investigated in a sample of 93 high adiposity and 93 low adiposity children, ages 8 to 13. A physical activity score (PAS) was computed for each child from a 2-day observation period. A physical working capacity index from cycle ergometry (PWC170) was the measure of CVF. Low and high adiposity samples were classified by a median split (42.9 mm) on the sum of three skinfold measures (tricep, suprailiac, subscapula). For the high adiposity sample, PAS, age, BMI, and gender were significant and the overall model was significant (p < .001), accounting for 38 % of variance in PWC170. In the low adiposity sample, gender (p < .04) was significantly related to CVF, but the overall model was not significant (p < .35). PAS, thus, was a significant predictor of CVF among the high adiposity children, but not the low adiposity children. Mechanisms that may account for this difference include greater work for equal activity among the obese, a ceiling effect on CVF among the low adiposity children, or differences in hormonal or metabolic factors mediating the activity-CVF relationship.  相似文献   

2.
Abstract

Even though the effect of single components contributing to weight gain in children have been addressed only limited research is available on the combined association of sports participation, physical fitness and time spent watching TV with body weight in children. Baseline data from 1594 children (809 male; 785 female), 7.1±0.6 years of age participating in a large school-based intervention in southern Germany was used. Height and weight was measured and body mass index (BMI) percentiles (BMIPCT) were determined accordingly. Sports participation and time spent watching TV was assessed via parent questionnaire while fitness was determined via a composite fitness test. Combined and single associations of sports participation, TV time and fitness with BMIPCT and weight status were assessed via ANCOVA as well as logistic regression analysis, controlling for age and sex. A significant interaction of TV time, sports participation and fitness on BMIPCT occurred, despite low correlations among the three components. Further, there was a combined association of sports participation and TV time on BMIPCT. TV time and fitness were also independently associated with BMIPCT. Similarly, only increased TV time and lower fitness were associated with a higher odds ratio for overweight/obesity. These results underline the complex interaction of TV time, sports participation and fitness with BMIPCT. In children, TV time and fitness have a stronger influence on BMIPCT compared to sports participation. Sports participation, however, may not reflect overall activity levels of children appropriately. More research is necessary to examine the complex interaction of various behaviours and fitness with BMIPCT.  相似文献   

3.
Abstract

As an increase in pain symptoms among children has been shown in the last decades, the aim of this study was to describe perceptions of recurrent pain, measured physical fitness and levels of reported physical activity (PA) in children, and to investigate if any associations between PA, fitness and recurrent pain could be identified. A school-based study comprised 206 Swedish children 8–12 years old, 114 boys, 92 girls. A questionnaire with questions about perceived pain, self-reported PA and lifestyle factors was used. Health-related fitness was assessed by 11 physical tests. A physical index was calculated from these tests as a z score. High physical index indicated high fitness and low physical index indicated low fitness. ANOVA test, chi-square test and logistic regression analysis were used to compare active and inactive children. The prevalence of one pain location (head, abdomen or back) was 26%, two 11% and three 4% (n=206). Female gender, living in single-parent families, low PA and low subjective health were associated with reported recurrent pain. Children reporting high levels of PA had high physical index and reported low prevalence of pain symptoms. The physical index and level of self-reported PA decreased gradually the more pain locations. Physically active children had higher fitness levels and reported less pain symptoms than inactive peers. Coping with pain is an integral part of PA, and active children learn to cope with unpleasant body sensations which together with high fitness may reduce the perception of pain.  相似文献   

4.
The present study examined the sex-specific associations of moderate and vigorous physical activity (VPA) with physical fitness in 300 Japanese adolescents aged 12–14 years. Participants were asked to wear an accelerometer to evaluate physical activity (PA) levels of various intensities (i.e. moderate PA (MPA), 3–5.9 metabolic equivalents (METs); VPA, ≥6 METs; moderate to vigorous PA (MVPA), ≥3 METs). Eight fitness items were assessed (grip strength, bent-leg sit-up, sit-and-reach, side step, 50?m sprint, standing long jump, handball throw, and distance running) as part of the Japanese standardised fitness test. A fitness composite score was calculated using Japanese fitness norms, and participants were categorised according to their score from category A (most fit) to category E (least fit), with participants in categories D and E defined as having low fitness. It was found that for boys, accumulating more than 80.7?min/day of MVPA may reduce the probability of low fitness (odds ratio (ORs) [95% confidence interval (CI)]?=?0.17 [0.06–0.47], p?=?.001). For girls, accumulating only 8.4?min of VPA could reduce the likelihood of exhibiting low fitness (ORs [95% CI]?=?0.23 [0.05–0.89], p?=?.032). These results reveal that there are sex-specific differences in the relationship between PA and physical fitness in adolescents, suggesting that sex-specific PA recommendation may be needed to improve physical fitness in adolescents.  相似文献   

5.
Abstract

The aims of this study were: (1) to characterize selected fitness and health attributes of two types of habitual recreational off-road vehicle riders – off-road motorcyclists and all-terrain vehicle riders; (2) to explore differences among riders in terms of vehicle type, age, and gender; and (3) to compare the fitness and health of riders to population norms and clinical health standards. Canadian off-road riders (n = 141) of both sexes aged 16 years and over were recruited through local and national off-road riding organizations. Anthropometry, fitness, and health measures of off-road motorcycle and all-terrain vehicle riders were compared with population norms, health standards, and physical activity guidelines. Off-road motorcycle riders had above average aerobic fitness (79th percentile), while all-terrain vehicle riders were lower than average (40th percentile). All riders had a healthy blood lipid profile and a low incidence of the metabolic syndrome (12.9%) compared with members of the general population. Off-road motorcycle riders had healthier body composition and fitness than all-terrain vehicle riders; however, the body composition of off-road motorcycle riders was no healthier than that of the general population and all-terrain vehicle riders were worse than the general population. Off-road motorcycle riders had healthier anthropometry and fitness than all-terrain vehicle riders and thus fewer health risk factors for future disease, demonstrating that the physiological profiles of off-road riders are dependent on vehicle type.  相似文献   

6.
Abstract

The incidence of orthopedic problems was examined in 5, 582 men and women who attended the Cooper Clinic in Dallas, Texas between 1974 and 1982. The effects of age, physical activity, physical fitness, and body mass index (EMI) on the occurrence of these problems were examined using a proportional hazards approach. The expected risk of orthopedic problems per person-year was 0.045 for men and 0.046 for women. For men, physical fitness, BMI, and physical activity were associated with orthopedic problems, while for women, physical activity was the main predictor. Age was not a factor for either gender. The effect of change in physical fitness, physical activity, and BMI was examined in a subset of 2, 325 persons with more than one visit to the clinic. For women, physical activity and a decrease in BMI were associated with orthopedic problems, while for men none of those factors were significant. Again, age was not a factor in either group. The absence of any age effect on the occurrence of problems suggests that with regard to orthopedic problems, moderate amounts of physical activity in generally healthy persons may be recommended without special consideration as to age.  相似文献   

7.
Abstract

The promotion of cardiorespiratory fitness through increased physical activity has become a national public health objective for both adults and children. Based on numerous small-scale studies it appears that children are highly fit but the population distribution is unknown due to the lack of rigorous population studies. Very little is known about the extent of children's physical activity; the available evidence does not support the hypothesis that children obtain sufficient activity to explain their generally high levels of fitness. Due to the lack of evidence of substantial carry-over effects of youth fitness to adult health and the likelihood of children's resistance to vigorous fitness routines, there is little reason to recommend an aerobic training focus in physical education. A focus on enjoyable moderate to vigorous physical activity (MVPA) with carry-over value to adulthood is recommended. Physical education is an important vehicle for promoting physical activity by children; it appears, however, that children may obtain little MVPA during physical education class.  相似文献   

8.
ABSTRACT

Purpose: Quality physical education (PE) reaches many objectives (e.g., knowledge, physical fitness, and physical skills) and could provide at least half the dose of recommended daily physical activity for youths if their opportunity to learn is provided according to national professional recommendations (min/week) and related state mandates. A 2015 California class-action lawsuit required affected schools to post data indicating they scheduled PE time meeting the state mandate of 200 min per 10-day period. The extent to which schools posted PE schedules on their websites and demographic factors related to their compliance was investigated in this study. Method: We performed a quantitative, cross-sectional content analysis of the websites of 37 school districts plus a random sample of 860 elementary schools in them. Z tests were used to analyze frequencies/proportions and associations among demographic (e.g., Hispanic enrollment, PE specialist) and PE schedule variables (e.g., schools meeting state-mandated PE time). Results: Twenty-two districts (59.4%) had websites with ≥1 page/document related to PE opportunities. Only 11% of schools posted PE schedules, an event that was associated with employing a PE specialist (p = .01). Of schools posting schedules, 68% specified a PE volume that met the state mandate. Meeting the mandate was independently associated with enrolling a minority of Hispanic students (p = .02). Conclusion: Websites can provide information about the importance/occurrence of PE; however, schools in the lawsuit did not use the potential of their websites to inform constituents either about the lawsuit or their PE programs. Non-compliant schools should adjust PE schedules to meet statutory requirements.  相似文献   

9.
Abstract

The purpose of this cross-sectional study was to examine the relationship between objectively measured physical activity, sedentary time, and cardiorespiratory fitness in a diverse sample of youth. Participants were recruited from three middle schools and completed assessments of height, weight, cardiorespiratory fitness, and wore an accelerometer for a minimum of four days. Hierarchical general linear models controlling for age, body mass index (BMI) percentile, and sex were used to evaluate the association of time (minutes per day) spent sedentary, and in moderate physical activity and vigorous physical activity with cardiorespiratory fitness (i.e., heart rate response [beats per minute], dependent variable). Results indicated age (β = –0.16, P < 0.05), BMI percentile (β = 0.33, P <0.05), being male (β = 0.17, P < 0.05), sedentary time (β = 0.11, P <0.05), moderate (β = –0.03, P > 0.05) and vigorous (β = –0.22, P < 0.05) physical activity explained 29% of the variance in cardiorespiratory fitness. Evaluation of fitness among high sedentary/high vigorous, high sedentary/low vigorous, low sedentary/low vigorous, and low sedentary/high vigorous groups (defined by the median split) showed that high levels of vigorous activity removed the detrimental effect of high levels of sedentary time on cardiorespiratory fitness. These analyses suggest that the negative impact of sedentary time can be mitigated by engaging in vigorous activity.  相似文献   

10.
Abstract

High physical fitness in childhood and adolescence is positively associated with favourable health-related outcomes. Our aim was to examine the relationship between relatives’ (father, mother, brother, sister, and best friend) physical activity engagement and encouragement on adolescents’ physical fitness. Adolescents were part of the HELENA study, a multi-centre study conducted in 10 cities from nine European countries in 2006–2008. Participants were 3288 adolescents (48% boys, 52% girls) aged 12.5–17.5 years with valid data on at least one of the three fitness variables studied: muscular strength (standing long jump), speed/agility (4×10 m shuttle run), and cardiorespiratory fitness (20 m shuttle run). The adolescents reported their relatives’ physical activity engagement and encouragement. Analysis of covariance showed that relatives’ physical activity engagement (father, mother, brother, and best friend) was positively related to cardiorespiratory fitness (P < 0.05); and mother's and sisters’ physical activity engagement were positively associated with higher muscular strength in adolescents (P < 0.05). Furthermore, father's physical activity encouragement was positively linked to physical fitness (all fitness components) in adolescents (P < 0.05). Interventions aimed at improving physical fitness in young people might be more successful when family members, particularly mothers and fathers, are encouraged to engage in physical activity and support adolescents’ physical activity.  相似文献   

11.
Abstract

The aim of this study was to examine the interrelationship between aerobic fitness, body composition, and physical activity in 9- and 15-year-olds. The 270 participants were randomly selected from 18 primary and secondary schools in Iceland. Aerobic fitness was assessed by a graded exercise test on a bicycle ergometer. Body composition was estimated via: logarithm of sum of four skinfolds (loge skinfolds), waist adjusted for height, and body mass index (BMI). Physical activity was measured with Actigraph activity monitors using total activity each day as the physical activity variable. Aerobic fitness was chosen as the primary outcome variable, body composition as the secondary variable, and physical activity as the tertiary variable. All the full models explained a similar proportion of fitness variance for both age groups (45–65%). Among the 15-year-olds, loge skinfolds explained a significantly larger proportion of the fitness variance (54%) than waist adjusted for height (29%) and BMI (15%), but all the body composition variables explained a similar proportion of the fitness variance (35–42%) among the 9-year-olds. Physical activity explained a smaller proportion (0%) of the unadjusted variance in fitness for the 9-year-olds than for the 15-year-olds (19%). This group difference became non-significant (0% vs. 4%) when adjusting for loge skinfolds but remained significant when controlling for waist adjusted for height (0% vs. 15%) and BMI (0% vs. 18%). Gender differences in aerobic fitness after puberty can largely be explained by gender differences in loge skinfolds and physical activity. In conclusion, the interrelationship between fitness, body composition, physical activity, and gender is not the same among 9- and 15-year-olds.  相似文献   

12.
Abstract

Maximum oxygen uptake ([Vdot]O2PEAK) is generally considered to be the best single marker for aerobic fitness. While a positive relationship between daily physical activity and aerobic fitness has been established in adults, the relationship appears less clear in children and adolescents. The purpose of this paper is to summarise recently published data on the relationship between daily physical activity, as measured by accelerometers, and [Vdot]O2PEAK in children and adolescents. A PubMed search was performed on 29 October 2010 to identify relevant articles. Studies were considered relevant if they included measurement of daily physical activity by accelerometry and related to a [Vdot]O2PEAK either measured directly at a maximal exercise test or estimated from maximal power output. A total of nine studies were identified, with a total number of 6116 children and adolescents investigated. Most studies reported a low-to-moderate relationship (r = 0.10–0.45) between objectively measured daily physical activity and [Vdot]O2PEAK. No conclusive evidence exists that physical activity of higher intensities are more closely related to [Vdot]O2PEAK, than lower intensities.  相似文献   

13.
ABSTRACT

Background: Motor competence, defined as a person’s ability to execute different motor skills, is directly associated with children’s physical, mental, and social development and may be essential in encouraging an active lifestyle in childhood. Although health-related quality of life (HRQoL) in children has been described as an individual’s subjective perception of the impact of health status on physical, psychological and social functioning, in very young children, a HRQoL parent-proxy report is needed since (pre)schoolchildren have problems expressing their feelings and understanding items on HRQoL instruments. In addition, the influence of motor competence on fitness levels has strong empirical support, so it seems reasonable to hypothesize that cardiorespiratory fitness might play a crucial role in the association between motor competence and HRQoL in children.

Objectives: This study examined the association between gross motor competence (G-MC) and HRQoL in typically developing children, and whether this association between G-MC and HRQoL was mediated by cardiorespiratory fitness.

Methods: An observational cross-sectional study with 1088 (pre)schoolchildren (51.84% boys, 48.16% girls) aged between 4 and 7 years (5.32?±?0.60) belonging to 21 schools in the Spanish provinces of Cuenca and Ciudad Real were included. G-MC was evaluated using the MABC-2 battery, HRQoL was assessed using the KINDL-R questionnaire and cardiorespiratory fitness using the 20m-shuttle-run-test. Partial correlations, covariance models and mediation analyses were conducted.

Results: The mean scores of HRQoL (physical well-being, self-esteem, friends, school and global score index) were significantly higher (p?<?0.05) in children with higher G-MC. When cardiorespiratory fitness was added as a covariate, all the results remained unchanged (p?<?0.05), except for physical well-being for the total sample as well as emotional well-being and the global score index for girls. Simple mediation analyses showed that cardiorespiratory fitness acted as a mediator between G-MC and physical well-being (Indirect Effect?=?0.04 [95% CI?=?0.01; 0.07]) for the total sample. For boys, it acted as a mediator between G-MC and physical well-being (Indirect Effect?=?0.04 [95% CI?=?0.00; 0.08]) and school (Indirect Effect?=?0.05 [95% CI?=?0.01; 0.09]), and, for girls, between G-MC and emotional well-being (Indirect Effect?=?0.04 [95% CI?=?0.01; 0.08]) and the global score index (Indirect Effect?=?0.02 [95% CI?=?0.00; 0.05]).

Conclusions: The results of this study suggest that good G-MC levels are associated with better HRQoL, mainly in global score index of HRQoL and self-esteem, friends, and school dimensions in typically developing children. Further, cardiorespiratory fitness mediates the association between G-MC and the physical dimension of HRQoL in (pre)schoolchildren. Additionally, physical and academic dimensions are mediated by cardiorespiratory fitness for boys and the emotional and global score indices of HRQoL are mediated by cardiorespiratory fitness for girls. These findings provide scientific evidence that improving motor competence and cardiorespiratory fitness might be a practical strategy to increase HRQoL in children. Thus, families and the educational community should promote effective interventions and incorporate opportunities inside and outside school that aim to jointly improve motor competence and cardiorespiratory fitness.  相似文献   

14.
Abstract

Physical inactivity is a risk factor for cardiovascular and other chronic diseases. It has been shown that both physical inactivity and social isolation increase with age, and that these factors are detrimental to physical and mental well-being. The purpose of the present study was to examine the relationship between physical inactivity and social isolation in older US adults. Using data from a nationally representative cross-sectional survey, the Third National Health and Nutrition Examination Survey, 1988–1994, we assessed the age- and race-specific prevalence of no leisure-time physical activity in relation to various forms of social interaction. The prevalence of no leisure-time physical activity increases with age in both men and women. In non-Hispanic whites, non-Hispanic blacks, and Mexican Americans, the prevalence of no leisure-time physical activity is increased in older US adults who are socially isolated. Social isolation is related to physical inactivity among persons 60 years and older. Longitudinal and intervention studies are needed to establish whether increased social support translates to a more active population of older adults.  相似文献   

15.
宁波市大学生体质监测及参加体育活动状况的调研   总被引:13,自引:0,他引:13  
通过运用体质监测、问卷调查、文献资料调研和数理统计等方法 ,对当前宁波市大学生的体质状况及参加体育活动情况进行调研分析。结果表明 :宁波市大学生身体形态、机能、素质指标均与全国同龄学生存在着一定的差异 ;宁波市大学生不同程度地参加体育活动 ,活动的时段以清晨为主 ,他们在选择活动项目、形式、场所时带有明显的性别特征 ,他们参加体育活动的动机不是单一的 ,而是多层次的 ,运动场所的不足和运动器材的短缺是影响他们参加体育活动的主要因素。  相似文献   

16.
Abstract

Although cross-sectional studies regarding the relationship between physical fitness and academic achievement among Japanese children have been previously reported, no longitudinal study has yet been reported for Japanese children. The purpose of this study was to examine the cross-sectional and longitudinal relationships between physical fitness and academic achievement among Japanese adolescents. This cohort study included 1,189 seventh- and ninth-grade students from two schools. The follow-up period was 2 years. A physical fitness test involving eight test items (hand grip, sit-ups, sit and reach, side-to-side jump, 20-m shuttle run, 50-m dash, standing broad jump and handball throwing) was conducted to evaluate the fitness of the participants. Academic achievement in Japanese, mathematics and a foreign language (English) was assessed at baseline and follow-up using cumulative guidance records. Participants were classified into low–low, high–low, low–high, and high–high groups based on physical fitness test results at baseline and follow-up. Compared with the groups showing low fitness levels, those showing high fitness levels for all items of the physical fitness test expect handball throwing had increased odds of showing high academic achievement levels in all three subjects at baseline and/or follow-up compared with the low-fitness groups. Sit-ups and 20-m shuttle run in the high–high and low–high groups were related to higher academic achievement levels at follow-up compared with those in the low–low group for both boys and girls. Therefore, this study suggests that various physical fitness outcomes are positively associated with high academic achievement levels for Japanese children.  相似文献   

17.
Purpose: Young adolescents who have little interest in participating in competitive team sports are at an increased risk for physical inactivity. Noncompetitive outdoor physical activity can provide young adolescents with increased opportunities to participate in physical activities that appeal to them and have positive health effects. The purpose of this study was to examine factors related to rural young adolescents' participation in noncompetitive outdoor physical activity to inform intervention design. Method: Young adolescents aged 10 to 14 years old (N = 1,032) from 1 rural county completed a self-administered questionnaire assessing constructs from self-determination theory (SDT) and the theory of planned behavior (TPB) related to noncompetitive outdoor physical activity. Structural equation modeling was used to examine an integrated conceptual model of hypothesized relationships among constructs. Results: The hypothesized conceptual model provided a good fit to the data with greater perceptions of autonomy support and self-determined motivation having statistically significant positive indirect effects on participation in noncompetitive outdoor physical activity mediated by the constructs of the TPB. All direct paths in the model were statistically significant; however, the direct effect of attitudes on intention was weak (.08) and self-determined motivation had no indirect effect on intention through attitudes (.03). Conclusions: Constructs of SDT and TPB should be accounted for by interventions targeting noncompetitive outdoor physical activity among young adolescents. More research is needed to determine young adolescents' preferences for noncompetitive and competitive physical activity and the potential influence that noncompetitive outdoor physical activity may have on total daily physical activity.  相似文献   

18.
The purpose of this study was to examine the mediating effect of resistance training skill competency on percentage of body fat, muscular fitness and physical activity among a sample of adolescent boys participating in a school-based obesity prevention intervention. Participants were 361 adolescent boys taking part in the Active Teen Leaders Avoiding Screen-time (ATLAS) cluster randomised controlled trial: a school-based program targeting the health behaviours of economically disadvantaged adolescent males considered “at-risk” of obesity. Body fat percentage (bioelectrical impedance), muscular fitness (hand grip dynamometry and push-ups), physical activity (accelerometry) and resistance training skill competency were assessed at baseline and post-intervention (i.e., 8 months). Three separate multi-level mediation models were analysed to investigate the potential mediating effects of resistance training skill competency on each of the study outcomes using a product-of-coefficients test. Analyses followed the intention-to-treat principle. The intervention had a significant impact on the resistance training skill competency of the boys, and improvements in skill competency significantly mediated the effect of the intervention on percentage of body fat and the combined muscular fitness score. No significant mediated effects were found for physical activity. Improving resistance training skill competency may be an effective strategy for achieving improvements in body composition and muscular fitness in adolescent boys.  相似文献   

19.

Purpose: This exploratory study examined the notion of Seefeldt's (1980) hypothesized motor skill “proficiency barrier” related to composite levels of health-related physical fitness (HRF) in young adults. Method: A motor skill competence (MSC) index composed of maximum throwing and kicking speed and jumping distance in 187 young adults aged 18 to 25 years old was evaluated against a composite index of 5 health-related fitness (HRF) test scores. MSC (high, moderate, and low) and HRF indexes (good, fair, and poor) were categorized according to normative fitness percentile ranges. 2 separate 3-way chi-square analyses were conducted to determine the probabilities of skill predicting fitness and fitness predicting skill. Results: Most correlations among HRF and MSC variables by gender demonstrated low-to-moderate positive correlations in both men (12/15; r = .23–.58) and women (14/15; r = .21–.53). Chi-square analyses for the total sample, using composite indexes, demonstrated statistically significant predictive models, χ 2 (1, N = 187) = 66.99, p < .001, Cramer's V = .42. Only 3.1% of low-skilled (2 of 65) individuals were classified as having a “good” HRF. Only 1 participant (out of 65) who demonstrated high MSC was classified as having “poor” HRF (1.5%). Conclusion: Although individual correlations among individual MSC and HRF measures were low to moderate, these data provide indirect evidence for the possibility of a motor skill “proficiency barrier” as indicated by low composite HRF levels. This study may generate future research to address the proficiency barrier hypothesis in youth as well as adults.  相似文献   

20.
Abstract

A large proportion of a child's day is spent at school interacting with certain physical surroundings, teachers, and school friends. Thus, schools could have a marked impact on establishing physical activity habits. The aim of the present study was to assess between-school variation in physical activity, aerobic fitness, and organized sports participation. Altogether, we tested 1766 nine- and fifteen-year-old children attending 242 school classes at 35 different schools in Denmark in 1997–2003. The intra-class correlation coefficient (ICC) for objectively assessed physical activity ranged between 0.06 and 0.18 depending on the dimension of physical activity and the time considered (i.e. school time vs. leisure time). For aerobic fitness, an ICC of 0.10 was observed, whereas that for organized sports participation ranged between 0.01 and 0.10 depending on the age group. Studying between-school variation in physical activity provides information about the extent to which children adjust their physical activity habits according to the social and environmental circumstances that they share, and helps to plan future school-based physical activity studies, especially in terms of sample size and power calculation.  相似文献   

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