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101.
102.

Background

Exergames (i.e., video games that require gross motor activity) may provide intrinsically motivating experiences that engage youth in sustained physical activity.

Method

Thirty-one low-income 15- to 19-year-old overweight and obese African American adolescents were randomly assigned to a competitive exergame (n = 17) or a cooperative exergame (n = 14) condition. Participants played a preassigned Wii Active exergame routine that took between 30 and 60 min each school day, and sessions occurred during lunch time or an after-school program over a 6 month period. Participation was voluntary, so students decided whether to come or not on a given day. Cooperative exergame players worked together with a peer to expend calories and earn points, while competitive exergame players competed individually against a peer to expend calories and earn points. Motivation was measured through surveys and interviews at the end of the intervention, and energy expenditure was measured by accelerometry during game play.

Results

Compared with the competitive group, the cooperative players were significantly more intrinsically motivated to play (p = .034, partial eta-squared = 0.366) and more psychologically attracted to the design of the exergame (p = .034, partial eta-squared = 0.320). Intrinsic motivation was significantly positively correlated with energy expenditure during game play: individuals who were motivated by control/choice had higher energy expenditure (p = .026), and those who were more goal motivated (p = .004) and more immersed in game play (p = .024) had lower energy expenditure during game play.

Conclusions

Cooperative exergame play produced higher intrinsic motivation to play the exergame than competitive exergame play did. Intrinsic motivation that came from a desire for control/choice was related to higher energy expenditure during game play. Cooperative exergame play holds promise as a method for engaging overweight and obese youth in physical activity.  相似文献   
103.
Summary Suitable animal models of human Type 1 (insulin-dependent) diabetes mellitus have long been sought, in particular a model that would permit detailed histological and immunological investigation of changes in the islet preceding the metabolic disorder. This would allow hypotheses as to pathogenesis of the condition to be examined and interventions such as immunotherapy to be tested. The most widely studied models include the low-dose streptozotocin induced diabetic mouse and the BB rat, but both differ in important respects from the human disease. In this review we describe one highly successful model, the non obese diabetic mouse. Selected aspects of pathogenesis and immunotherapy are presented and analogies with human Type 1 diabetes discussed.  相似文献   
104.
目的了解学龄前单纯性肥胖儿童运动行为特征,为制订肥胖儿童运动处方提供依据。方法随机整群抽取海门市市区、农村各4所幼儿园共30个班级中所有单纯性肥胖儿童,按照1:1配对正常儿童,调查运动行为特征。结果发现肥胖儿童园外体育运动的频率低于非肥胖儿童(χ2=10.766,P<0.05),放学后留在幼儿园参与大型玩具活动也少(χ2=45.006,P<0.01), 非肥胖儿童的平均体育运动时间为22.5 min,而正常儿童为28.6 min,肥胖组儿童喜欢散步、跑步、玩球,非肥胖组儿童更喜欢玩球、骑车、跳舞,肥胖组大运动发育商较低。结论肥胖儿童的日常体育运动水平较低、活动时间较短,更倾向于身体移动较小、技巧性较低的运动项目23。  相似文献   
105.
Purpose: To compare visualization of first trimester fetal anatomic transvaginal ultrasound (TVUS) to the second trimester transabdominal anatomic ultrasound (TAU) in normal weight and obese patients.

Materials and methods: In a prospective cross-sectional study design, 25 women underwent a TVUS between 12 and 14 weeks, and a TAU at 18–22 weeks. For each anatomic structure, the percentage of patients achieving optimal visualization was recorded. Risk ratios for visualizing a structure in the second trimester versus the first were calculated.

Results: Twenty-five patients underwent a TVUS and 24 completed the TAU. The average BMI in the obese and nonobese groups was 34?kg/m2 and 23?kg/m2, respectively. All structures were more consistently visualized during the TAU for the both groups. The cardiac views, hands and feet were more difficult to visualize in all the patients at both scan times but were more frequently visualized in the TAU. For the obese patients, hands, feet, cardiac and spine views were less frequently visualized in both the scans. The posterior fossa and profile views were more difficult to obtain in the TVUS.

Conclusions: The first trimester TVUS detects many of the structures assessed during an anatomic survey; however, it is not superior to the second trimester TAU in normal weight and obese patients.  相似文献   
106.
目的:探讨抑制素B(inhibin,INH-B)水平在多囊卵巢综合征(PCOS)患者血清中的变化及其与体重指数(BMI)的关系。方法:筛选PCOS患者40例,根据体重指数(BMI)分为肥胖组和非肥胖组并检测血清中的抑制素B(INH-B)、胰岛素生长因子-I(IGF-I)、空腹胰岛素(In)、瘦素(leptin)、黄体生成素(LH)、卵泡刺激素(FSH)、人体催乳素(PRL)、雌二醇(E2)和睾酮(T),另取40例排卵正常、无怀孕妇女做对照分析。结果:PCOS患者肥胖组leptin、In、LH、T水平明显高于非肥胖组,INH-B、IGF水平则明显低于非肥胖组,差异有统计学意义(P〈0.05);且肥胖组的LH与INH-B呈负相关(r=-0.735,P〈0.05),非肥胖组的LH与INH-B无明显相关性。非肥胖组INH-B、IGF、LH、T水平明显高于对照组,差异有统计学意义(P〈0.05)。结论:INH-B与多囊卵巢综合征(PCOS)发生有关,且作为PCOS特征的肥胖又影响着INH-B的作用和水平。  相似文献   
107.
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Adult female Zucker lean and obese rats were treated for 14 days with 3.5 nm/kg oleoyl-estrone (OE) in liposomes (Merlin-2) through continuous i.v. injection with osmotic minipumps. Rat wt. and food intake were measured daily. On days 0, 3, 6, 10, and 14, groups of rats were killed and their hypothalamic nuclei [lateral preoptic (LPO), median preoptic (MPO), paraventricular (PVN), ventromedial (VMH), and arcuate (ARC)] were dissected, homogenized, and used for the measurement of corticosterone-releasing hormone (CRH) by radioimmunoassay. The OE treatment decreased food intake by 67.4% in lean and 62.6% in obese rats (means for 14 days). Body wt. decreased steadily in lean and obese rats, the gap between controls and treated rats becoming 11.5% of initial body wt. in the lean and 12.4% in the obese. The levels of CRH in the ARC nucleus were at least 10-fold higher than in the other nuclei. No changes in CRH were observed in any of the nuclei of obese rats, with levels up to day 6 similar to those of lean rats. In the lean rats, the LPO and ARC nuclei showed peaks on day 10, while the MPO showed no changes and the PVN and VMH nuclei showed a progressive increase, to a maximum at the end of the study (day 14). This contrasted with the peak of plasma adrenocorticotropic hormone (ACTH) and corticosterone (day 6 in lean and day 14 in obese rats). There was a definite lack of correlation between the plasma levels of these two hormones and the levels of CRH in the hypothalamic nuclei, and between the latter and the decreases in appetite in the rats. The loss of appetite induced by OE is not necessarily mediated by CRH, because the obese rats show an intense decrease in voluntary food intake but their hypothalamic nuclei CRH levels do not change at all. Hypothalamic nuclei CRH does not, necessarily, mediate the rise in glucocorticoids induced by OE treatment, because this is observed in lean and obese rats, lean rats increases being mismatched with those of hypothalamic CRH. The OE induced changes in hypothalamic CRH require a fully functional leptinergic pathway, because it is not observed in Zucker fa/fa rats lacking a working leptin receptor. This–indirectly–shows that leptin is needed for its synthesis or modulation.  相似文献   
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