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101.
OBJECTIVE: To develop and examine the efficacy of a computer-based interactive multimedia curriculum for promoting physical activity in fourth grade children. RESEARCH METHODS AND PROCEDURES: The participants were 209 fourth grade children (mean age of 9.5 +/- 0.4 years) from four schools. Two schools received an 8-week multimedia intervention delivered by interactive CD-ROM, supplemented by four classroom and four homework assignments. Two control schools received educational CD-ROMS not related to health outcomes. Measures conducted before and after intervention included height, weight, percentage body fat (bioimpedance analysis), physical activity (5-day accelerometry), and psychosocial aspects of physical activity by questionnaire. All outcomes were examined using general linear models. RESULTS: There was a significant treatment effect for obesity reduction in girls but not in boys. There were no significant treatment effects on total physical activity by accelerometry (total counts per minute), but there was an overall treatment effect on reducing percent of time in moderate-intensity activity (16.5% to 15% of the time) and significant sex-by- treatment interactions for light-intensity activities (reduction in boys from 78% to 75% of the time and an increase in girls from 78% to 81% of the time). There were marginal/significant treatment effects for improvements in behavioral outcomes, including self-efficacy (p = 0.06), social norms (p = 0.07), and outcome expectancies (p = 0.049). DISCUSSION: The interactive multimedia curriculum favored an improvement in obesity indices in girls and was associated with subtle changes in physical activity in girls and general improvement in psychosocial outcomes related to physical activity. 相似文献
102.
Davis JN Ventura EE Weigensberg MJ Ball GD Cruz ML Shaibi GQ Goran MI 《The American journal of clinical nutrition》2005,82(5):1004-1010
BACKGROUND: Few studies have investigated the association between sugar intake and insulin dynamics in children, and none have examined this association in overweight Latino youth. OBJECTIVE: We aimed to examine the relation between dietary components, especially sugar intake, and insulin dynamics in overweight Latino youth. DESIGN: We examined 63 overweight Latino children aged 9-13 y. Dietary intake was determined by 3-d records, and body composition was measured with dual-energy X-ray absorptiometry. Insulin sensitivity (S(I)), acute insulin response (AIR), and disposition index (an index of beta cell function) were measured by using a frequently sampled intravenous-glucose-tolerance test and minimal modeling. Hierarchical regression analysis ascertained the potential independent relation between insulin dynamics and dietary components. RESULTS: The relation between macronutrient intake and any variable related to insulin dynamics was not significant. However, higher total sugar intake, although not related to S(I), was significantly associated with lower AIR (beta = -0.296, P = 0.045) and lower beta cell function (beta = -0.421, P = 0.043), independent of the covariates age, sex, body composition, Tanner stage, and energy intake. Sugar-sweetened beverage intakes trended toward inverse association with lower AIR (beta = -0.219, P = 0.072) and beta cell function (beta = -0.298, P = 0.077). CONCLUSIONS: In overweight Latino children, higher intakes of sugar and sugar-sweetened beverages were associated with lower AIR and disposition index, which suggested that these children already have early signs of poor beta cell function. These results emphasize the need for early nutritional interventions to reduce daily sugar intake in overweight Latino children and potentially reduce their risk for type 2 diabetes. 相似文献
103.
Adiponectin is inversely related to adiposity and positively correlated with insulin sensitivity (S(i)). Sparse data exist on the contributions of ethnicity and body fat distribution to variance in serum adiponectin. Hypotheses tested were that adiponectin would be lower in African Americans compared with Caucasians; that adiponectin would be inversely related to central, not peripheral, fat; that adiponectin would be positively associated with S(i); and that baseline adiponectin would predict change in S(i) over 2 years in 150 African-American and Caucasian youth. Multiple linear regression modeling showed that adiponectin was lower in African-American versus Caucasian children (adjusted means 10.8 +/- 0.5 vs. 12.3 +/- 0.5 microg/ml, respectively; P < 0.05); inversely related to trunk fat (P < 0.05); and positively related to limb fat (P < 0.01). Addition of the acute insulin response to glucose to the model eliminated the significance of ethnicity. S(i), which was positively related to adiponectin (P < 0.05), was lower in African Americans (P < 0.001) and girls (P < 0.05). Baseline adiponectin did not predict change in S(i) over 2 years. In conclusion, adiponectin was positively correlated with S(i), inversely related to central fat, and positively related to peripheral fat. In addition, higher acute insulin response to glucose explained lower adiponectin among African-American children. 相似文献
104.
Popović-Bijelić A Bijelić G Jorgovanović N Bojanić D Popović MB Popović DB 《Artificial organs》2005,29(6):448-452
We designed a 24-field array and an on-line control box that selects which and how many of 24 fields will conduct electrical charge during functional electrical stimulation. The array was made using a conductive microfiber textile, silver two-component adhesive, and the conductive ink imprint on the polycarbonate. The control box comprised 24 switches that corresponded one-to-one to the fields on the array. Each field could be made conductive or nonconductive by simple pressing of the corresponding push-button type switch on the control box. We present here representative results of the selectivity of the new electrode measured in three tetraplegic patients during functional electrical stimulation of the forearm. The task was to generate finger flexion and extension with minimal interference of the wrist movement during lateral and palmar grasps. Therapists determined the appropriate pattern that lead to effective grasping, lasting on average 5 min per stimulation channel in the first session. This optimal conductive pattern (size and shape) provided effective finger flexion and extension with minimal wrist flexion/extension and ulnar/radial deviations (<10 degrees). The optimal size and shape of the electrode in all cases had a branched pattern. The selection of the optimal stimulation site was achieved without moving the electrode. The size and shape were reproducible in the same subject from session to session, yet were different from subject to subject. The optimal electrode size and shape changed when subjects pronated and supinated their forearm. The control box includes a program that can dynamically change the number and sites of the conductive fields; hence, it is feasible to use this during functional movements. Subjects learned how to determine the optimal electrode pattern; hence, these electrodes could be effective for home usage. 相似文献
105.
BACKGROUND: Previous studies have suggested an association between personality traits and post-traumatic stress. These studies either focused exclusively on military veterans or assessed personality traits after the traumatic event. This study investigates to what extent personality traits as assessed before the traumatic experience predict post-traumatic stress in civilians experiencing air attacks at the end of the exposure to stressful events and 1 year later. METHOD: The revised version of the NEO Personality Inventory was administered to 70 students in Belgrade, Yugoslavia. In 1999, 1 or 2 years after the assessment, all students were exposed to air attacks for 11 weeks. At the end of the attacks and 1 year later post-traumatic stress was measured on the Impact of Event Scale. RESULTS: Pre-trauma personality predicted 13% of the variance of intrusion scores 1 year after the attacks. There was no significant correlation between personality traits and subsequent avoidance scores at any point of time. CONCLUSIONS: Personality traits that are assessed before a traumatic event can, to a limited extent, predict intrusive symptoms in a non-clinical sample of civilians. Pre-trauma assessments of personality might be less strongly associated with post-traumatic stress than personality traits obtained after the traumatic event. 相似文献
106.
Guevara R Velazquez JL Nenadovic V Wennberg R Senjanovic G Dominguez LG 《Neuroinformatics》2005,3(4):301-314
Phase synchrony analysis is a relatively new concept that is being increasingly used on neurophysiological data obtained through different methodologies. It is currently believed that phase synchrony is an important signature of information binding between distant sites of the brain, especially during cognitive tasks. Electroencephalographic (EEG) recordings are the most widely used recording technique for recording brain signals and assessing phase synchrony patterns. In this study, we address the suitability of phase synchrony analysis in EEG recordings. Using geometrical arguments and numerical examples, employing EEG and magnetoencephalographic data, we show that the presence of a common reference signal in the case of EEG recordings results in a distortion of the synchrony values observed, in that the amplitudes of the signals influence the synchrony measured, and in general destroys the intended physical interpretation of phase synchrony. 相似文献
107.
Mestrovic J Kardum G Polic B Omazic A Stricevic L Sustic A 《European journal of pediatrics》2005,164(12):783-784
108.
Ball GD Weigensberg MJ Cruz ML Shaibi GQ Kobaissi HA Goran MI 《International journal of obesity (2005)》2005,29(12):1471-1477
OBJECTIVE: To examine cross-sectional differences in insulin sensitivity, insulin secretion and beta-cell function during puberty in overweight Hispanic boys and girls with a family history of type 2 diabetes. STUDY DESIGN AND PARTICIPANTS: This cross-sectional, observational study included 214 8-13-y-old Hispanic children with a BMI percentile > or = 85th percentile and family history of type 2 diabetes. METHODS AND ANALYSES: Participants underwent a physical examination, body composition measures, oral glucose tolerance test (OGTT), and frequently-sampled intravenous glucose tolerance test. Unadjusted and adjusted general linear models (GLM) tested whether insulin/glucose dynamics differed by Tanner stage and gender. RESULTS: Unadjusted group comparisons showed that fasting insulin increased whereas insulin sensitivity (SI) and the disposition index (DI) (a measure of pancreatic beta-cell function) decreased across Tanner stage groups (all P < 0.05). No differences in the acute insulin response to glucose (AIRg), fasting glucose or 2-h glucose were found. After adjusting for covariates, there was no independent effect of Tanner stage on SI (P = 0.9) or AIRg (P = 0.2), but DI was slightly lower in later Tanner stages suggesting decreased beta-cell function in the more mature groups (P = 0.10). CONCLUSIONS: Overweight Hispanic children with a family history of type 2 diabetes may represent a unique population given that pubertal insulin resistance was not evident once analyses controlled for body composition. Longitudinal analyses are required to determine whether the slightly diminished beta-cell function in later Tanner stages plays a role in the development of type 2 diabetes. 相似文献
109.
Rafajlovski S Orozović V Raden G Ristić-Andelkov A 《Vojnosanitetski pregled. Military-medical and pharmaceutical review》2005,62(9):629-635
AIM: To present the results and experience in diagnosing and treating of patients with acute right ventricle infarction, during the period of hospitalization of one month, with adjuvant analyses of the obtained results in the period of fifteen years. METHODS: Acute right ventricle infarction porved clinicaly, enzymologicaly, by ECG, echochardiographically or scintigraphically we treated with thrombolitic therapy within first six hours after admittion, with salvaged PTA in case of the cardiogenic shock or AV block II degrees-III degrees despite of thrommbolitic therapy, or with postponed PTA within first month of intrahospital treatment. RESULTS: In the period from 1990 to 2004, 3 225 patients of both sexes were treated for acute myocardial infarction at the different localization in patients' at the mean age of 53.7 +/- 5.8. One-hundred-thirty-nine (43.9%) patients were treated with thrombolitic therapy according to the speed up protocole. Heparin was administered to 160 (50.7%) patients with water load, and 17 (5.4%) patients had the primary percutaneous transluminal coronary angioplasty (PPTCA), so that the mechanical blood flow could be established, by the implantation of a stent when necessary. In 316 patients with right ventricle infarction, 58 (18.3%) had postponed and salvaged percutaneous transluminal coronary angioplasty (PTCA). Twenty-two (15.8%) patients had thrombolitic therapy, whereas 36 (22.5%) patients were treated with heparin. We had a successful balloon dilatation in 21 (36.2%), whereas 32 (55.2%) patients had 1-3 intracoronary stents inplanted, depending upon the necessity, and 5 (8.6%) patients from this group were sent to surgical intervention. In the group of 214 (67.7%) patients treated with heparin or thrombolitic therapy combined therapy, with PTCA, 12 (5.7%) patients died, whereas in the group of 124 (39.3%) patients treated only with heparin 26 (16.2%) patients died, statistically significant difference (p < 0.001, chi2 = 18.423). Was noticed n the group of 1 204 patients with inferoposterior infarction, 122 (10.1%) patients died. In the group of 316 patients with right ventricle infarction, 38 (12%) died. In the group of 888 control patients with inferoposterior infarction, but without right ventricle infarction, 84 (9.4%) patients died. In the group of 2 021 patients (62.2%) with anterior infarction, 248 (12.3%) died. CONCLUSION. The obtained results showed that the patients with right ventricle infarction, due to the great expansion of necrosis and the involvement of the inferoposterior wall of the left ventricle, as well as the ischemia of sinus and AV nodes, were the patients of a high risk. That was why it was essential to do urgent widening of the artery to reestablish blood flow either by using drugs or by means of mechanical methods. 相似文献
110.
Misović S Kronja G Ignjatović D Tomić A 《Vojnosanitetski pregled. Military-medical and pharmaceutical review》2005,62(3):243-246
A case of a 22-year old soldier, with a history of pain in the leg during heavy exercise, which desisted at rest, was presented. One day before admission, the patient had felt an extreme exertion-induced pain in his right leg which had not lessenned at rest. At the same time, the patient noticed persistent severe leg edema. On physical examination, the intracompartmental pressure was 62 mmHg (> 30 mmHg). The patient was urgently operated on, and fasciotomy according to Mubarak was used. At second surgery, the debridement of the muscles of the posterior group of the leg, and the evacuation of hemathoma from the anterior and lateral group of the right leg muscles were perfomed. Postoperative recovery was uneventful. Fasciotomy wounds were closed within 14 days of the surgery. The complete physical treatment was done. Follow-up examinations 1, 3, and 6 months afterwards were satisfactory. The soldier completed his compulsory military service without any sequelae. Laboratory results were normal. Overlooked, unrecognized or surgically untreated compartment syndrome can cause severe damage, including even the loss of the extremity. 相似文献