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101.

Background  

The influence of the family and home environment on childhood physical activity (PA) and whether this differs between ethnic groups remains uncertain. This paper investigates associations between family and home factors and childhood PA in a multi-ethnic population and explores whether associations differ between ethnic groups.  相似文献   
102.
Knowledge of the contribution of supplements to overall nutritional health is limited. The research objectives were to describe motivations for use of dietary supplements by African Americans and Whites examined in the Healthy Aging in Neighborhoods of Diversity across the Life Span (HANDLS) study and to determine if supplements provided beneficial effects to micronutrient diet quality and nutritional and cardiovascular biomarkers. The majority of the HANDLS study population were smokers, overweight or obese, and self-reported their health as poor to good. The top two reasons for their supplement use were to supplement the diet and to improve overall health. Micronutrient intake was calculated from two 24-hour recalls and a supplement questionnaire. Diet quality was assessed by the Mean Adequacy Ratio (MAR) [Maximum score?=?100] derived from the Nutrient Adequacy Ratio (NAR) for 17 micronutrients. The MAR score for nonusers was 73.12, for supplement users based on diet alone was 74.89, and for food and supplements was 86.61. Dietary supplements significantly increased each NAR score and MAR score. However, there were no significant differences between the population proportions with inadequate or excessive blood levels for any biomarkers examined. Nutrition education programs and intervention strategies addressing dietary supplement intake might lead to healthier food choices and may improve the health of this population.  相似文献   
103.
OBJECTIVE: An orally administered antimicrobial regimen for the treatment of group A beta-hemolytic streptococcal (GABHS) pharyngitis given once rather than multiple times each day would be more convenient and might result in improved patient compliance. The purpose of this study was to evaluate the effectiveness of once-daily amoxicillin in the treatment of GABHS pharyngitis. PATIENTS: Children presenting to a private pediatric office with GABHS pharyngitis. DESIGN: Patients were randomly assigned to receive orally either amoxicillin (750 mg once daily) or penicillin V (250 mg three times a day) for 10 days. Compliance was monitored by urine antimicrobial activity. OUTCOMES: Outcomes were measured by impact on the clinical course, eradication of GABHS within 18 to 24 hours, and bacteriologic treatment failure rate as determined by follow-up throat cultures 4 to 6 and 14 to 21 days after completing therapy. GABHS isolates were serotyped to distinguish bacteriologic treatment failures (same serotype as initial throat culture) from new acquisitions (different serotypes). RESULTS: During the 16 months of this study, 152 children between 4 and 18 years of age (mean, 9.9 years) were enrolled; 79 children were randomly assigned to receive once-daily amoxicillin and 73 were assigned to receive penicillin V three times a day. The children in the two treatment groups were comparable with respect to age, duration of illness before initiation of therapy, compliance, and signs and symptoms at presentation. There was no significant difference in the clinical or bacteriologic responses of the patients in the two treatment groups at the 18- to 24-hour follow-up visit. Bacteriologic treatment failures occurred in 4 (5%) of the 79 patients in the amoxicillin group and in 8 (11%) of the 73 patients in the penicillin V group. CONCLUSIONS: These data demonstrate that once-daily amoxicillin therapy is as effective as penicillin V therapy given three times a day for the treatment of GABHS pharyngitis, and if confirmed by additional investigations, once-daily amoxicillin therapy could become an alternative regimen for the treatment of this disease.  相似文献   
104.
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106.
Background: Dentine matrix metalloproteinases (MMPs) may participate in the destruction of dentine following demineralization by bacterial acids. This study investigated the localization of MMPs in carious dentine. Methods: Frozen sections of dentine caries were prepared without demineralization and immersed in monoclonal antibody against MMP‐2, ‐8, ‐9 and ‐20. The sections were labelled by IgG conjugated with gold colloidal particles, and observed under FE‐SEM. Labelling indexes (number of gold particles/μm2) of outer and inner carious dentine, respectively, with and without bacterial infection, were compared with that of normal dentine. Results: MMP‐2 was distributed in both carious and normal dentine; the level of MMP‐2 showed no significant difference among the outer caries, inner caries, and normal dentine. The labelling indexes of MMP‐8 and MMP‐9 both significantly decreased at the inner carious dentine compared with the level of normal dentine, but intensified again at the outer caries region. The labelling index of MMP‐20 was the highest at normal dentine. Conclusions: The localization of MMPs was visibly detected using immunogold labelling. The localization of MMP‐2 showed no significant difference among the three regions, while MMP‐8 and MMP‐9 showed significant reduction at the inner caries layer, and MMP‐20 reduced toward the outer caries.  相似文献   
107.
PurposeTo examine effects of race and predictors of socioeconomic status (SES) on nutrient-based diet quality and their contribution to health disparities in an urban population of low SES.DesignData were analyzed from a sample of the Healthy Aging in Neighborhoods of Diversity Across the Life Span (HANDLS) Study participants examining effects of age, sex, race, income, poverty income ratio, education, employment, and smoking status on nutrient-based diet quality as measured by a micronutrient composite index of nutrient adequacy ratios and a mean adequacy ratio. Regression models were used to examine associations and t tests were used to look at racial differences.SubjectsAfrican American and white adults ages 30 to 64 years residing in 12 predefined census tracts in Baltimore, Maryland.ResultsSex, age, education, poverty income ratio, and income were statistically significant predictors of diet quality for African Americans, while sex, education, and smoking status were statistically significant for whites. African Americans had lower mean adequacy ratio scores than whites (76.4 vs 79.1). Whites had significantly higher nutrient adequacy ratios scores for thiamin, riboflavin, folate, B12, vitamins A and E, magnesium, copper, zinc, and calcium, while African Americans had higher vitamin C scores.ConclusionEducation significantly impacted diet quality in the HANDLS sample, but race cannot be discounted. Whether the racial differences in diet quality are indicative of cultural differences in food preferences, selection, preparation, and availability, or disparities in socioeconomic status remains unclear.  相似文献   
108.
109.
Rhabdomyosarcoma (RMS) is the most common soft tissue tumour in children, with the head and neck region accounting for 35–40% of cases. Nasopharyngeal RMSs tend to grow rapidly and invade adjacent structures. Both the Intergroup Rhabdomyosarcoma Studies and the European Studies have established that the ideal management of this disease is multimodal, using a combination of surgery, chemotherapy and radiotherapy. This case series examines the role of radiotherapy in the management of paediatric nasopharyngeal RMSs, with particular reference to long-term morbidity and disease-free survival. The cases of five children with nasopharyngeal RMS were reviewed and a systematic review of the literature contained in the PubMed databases was conducted to establish 24 individually detailed cases. Management in all patients was multimodal, using a combination of chemotherapy, radiotherapy as well as surgery. External beam radiotherapy is an integral component of treatment for nasopharyngeal RMSs. With more patients surviving for longer periods, more long-term sequelae of radiotherapy have been reported. Complications include sensorineural deafness, endocrine manifestations following radiation of the pituitary gland, cranial nerve palsies, second malignancies within the radiation field, cataract formation, retinopathy and growth disturbance. Morbidity from radiotherapy may be considerable and depends on the field and dose of radiation. Current advances in radiotherapy are aimed at improving the rate of tumour control and reducing such complications. Recent improvements in imaging and conformal techniques have the potential to reduce the morbidity associated with radiotherapy in this cohort.  相似文献   
110.

Background  

The Brazilian response towards AIDS epidemic is well known, but the absence of a systematic review of vulnerable populations ─ men who have sex with men (MSM), female sex workers (FSW), and drug users (DU) remains a main gap in the available literature. Our goal was to conduct a systematic review and meta-analysis of studies assessing HIV prevalence among MSM, FSW and DU, calculating a combined pooled prevalence and summarizing factors associated the pooled prevalence for each group.  相似文献   
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