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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.
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   
103.
The absence of large von Willebrand factor (vWF) multimers from plasma is a characteristic of Type IIA von Willebrand's disease (vWD) and is thought to contribute to the clinical expression of this disorder. Recently, three IIA patients have been reported in whom intermediate and large multimers could be restored if blood were collected in 5 mm EDTA, 6 mmol/L N-ethylmaleimide, and 1 mmol/L leupeptin. This suggested that absence of large multimers resulted from in vitro proteolysis. We have now collected blood from ten Type IIA vWD patients in these inhibitors but were not able to detect large multimers in the plasma of any of them. In addition, intermediate-sized multimers were reduced or completely absent in all. The inclusion of inhibitors in the citrate anticoagulant, as compared to citrate alone, was found to increase the relative proportion of intermediate multimers in some patients but had no effect in others, and in none did it restore large multimers to plasma. The results with platelet vWF were more varied. Four patients showed an absence or decrease of large multimers, whereas in seven patients large multimers were present. When compared with citrate anticoagulant alone, the inclusion of inhibitors in the anticoagulant had little or no effect on the platelet multimeric pattern. 1-Deamino-8- D-Arginine Vasopressin (DDAVP) was administered to six patients from five families. Two patients from one family showed complete correction and a third patient showed almost complete correction of her bleeding time. Two patients showed minimal correction and one showed no detectable correction. An increase in multimer size after DDAVP tended to be associated with correction of the bleeding time. However, in no case did the largest multimers appear in plasma even in patients with complete bleeding time correction. The presence or absence of inhibitors in the anticoagulant had little or no effect on the multimeric pattern after DDAVP. These results indicate that Type IIA vWD is a heterogeneous disorder in which absence of largest and intermediate multimers is an in vivo phenomenon.  相似文献   
104.
105.
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   
106.
107.
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   
108.

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   
109.
收集脊柱损伤的信息对于脊髓损伤患者的诊断和治疗非常重要,设立脊髓损伤患者脊柱损伤基础数据集是为了规范脊柱损伤相关信息的收集方式和报告内容,学习并使用国际脊髓损伤脊柱损伤基础数据集,有助于规范和统一我国脊髓损伤患者脊柱损伤信息的收集,为相关治疗提供依据。本文将介绍国际脊髓损伤脊柱损伤基础数据集的研发过程,数据元素的内容以及数据编码的应用实例。  相似文献   
110.
ObjectiveThe objective of this observational study was to compare the International Index of Erectile Function (IIEF-5) with penile duplex in the diagnosis of vasculogenic erectile dysfunction severity. 150 subjects complaining of erectile dysfunction for >6 months have been divided into two groups according to their response to intracavernous injection (ICI) test; 50 patients who showed good response ? (E4) and one hundred patients who showed poor response ? (E4) up to maximum dose of 1 cc Quadmix with abnormal penile duplex. The results of the duplex are correlated to the IIEF-5 score of the patients.FindingsThere is statistically significant difference between mean value of IIEF-5 in both good and poor responders (P-value = 0.0000), significant difference between mean value of (age, duration, PSV, EDV, diameter of artery after injection, percent of increase in arterial diameters and RI) between the good and poor responders. There was no evidence of statistically significant difference between mean value of IIEF-5 in both arteriogenic and venogenic subgroups of poor responders group. There was neither evidence of statistically significant correlations between IIEF-5 and penile duplex results in both good and poor responders groups, nor between IIEF-5 and penile duplex results in arteriogenic and venogenic and combined subgroups.ConclusionIIEF-5 might not be a suitable diagnostic tool of the severity of vascular affection in ED.  相似文献   
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