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OBJECTIVES: Although asthma, allergic rhinitis and eczema are among the most common chronic diseases in children worldwide, there is very limited information about the burden of these conditions in Oman. The aim of this study was to determine the prevalence and severity of symptoms of asthma, allergic rhinitis and eczema in Omani schoolchildren using the International Study of Asthma and Allergies in Childhood (ISAAC) Phase I questionnaire. METHODS: An Arabic version of the ISAAC Phase I questionnaire was completed by parents of 3893 children aged 6-7 years and self-completed by 3174 children aged 13-14 years, randomly selected from a nationwide sample of public schools. RESULTS: The prevalence rates of reported diagnoses of asthma, allergic rhinitis and eczema were higher in older children (20.7%, 10.5% and 14.4% compared with 10.5%, 7.4% and 7.5%, respectively, in young children). In young children, 277 were current wheezers and of these 40.8% had sleep-disturbing wheeze at least once a week and 45.1% had speech-limiting wheeze during the past year. Similarly, 283 older children were current wheezers, and of these 30.0% had sleep-disturbing wheeze at least once a week and 37.5% had speech-limiting wheeze during the past year. Exercise-induced wheeze was higher in older children (19.2% vs 6.9%; P < 0.001). Allergic rhinitis and eczema were also associated with significant sleep disturbance and limitation of activity in both age groups. CONCLUSION: Allergic conditions in Omani schoolchildren are common and associated with significant morbidity. Further research is required to identify the local risk factors for allergy to allow better understanding and management of these conditions.  相似文献   
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The administration of sodium diethyldithiocarbamate to 18 day pregnant mice, which previously had been given 109Cd2+ or 203Hg2+ was found to result in increased levels of the metals in the foetuses, in comparison with mice given the 109Cd2+ or 203Hg2+ alone. The level of 109Cd2+ in some foetal tissues was increased 30-60 times. In the animals given 203Hg2+ 3-5 times higher concentrations were seen in most foetal tissues of the sodium diethyldithiocarbamate-treated animals compared with animals not treated with this substance. Cadmium and mercury were shown to form highly lipophilic complexes with diethyldithiocarbamate and a facilitated transfer of these complexes through the placental membranes probably explains the increased uptake of the metals in the foetuses.  相似文献   
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Background: Today, despite many studies on the diagnosis of metastasis to lymph nodes (LNs) in Rectal Cancer (RC), its diagnosis is still very challenging for radiologists. The purpose of the present study was to the assessment of the diagnostic value of conventional MRI, DCE-MRI, and DWI-MRI in the discrimination of metastatic from non-metastatic lymph nodes in RC. Methods: In the present meta-analysis study, we surveyed international databases including PubMed, Scopus, Embase, and Science Direct with appropriate keywords. Using the binomial distribution formula, the variance of each study was calculated and the data were analyzed using STATA version 14. Finally, the results of the studies were entered into the random-effects meta-analysis.  Also, we used the chi-squared test and I2 index to calculate heterogeneity among studies, and for evaluating publication bias, Funnel plots and Egger tests were used. Results: 31 articles published between 2005 and 2021, comprising 2517 patients were included in the present study. The sensitivity and specificity of DCE-MRI were 83% (74% to 80%), and 86% (80% to 93%), respectively with PPV 84% (76% to 89%) and NPV 88% (79% to 95%). Also, the sensitivity and specificity of DWI-MRI were 81% (74% to 88%), and 74% (78% to 91%), respectively with PPV 63% (54% to 74%), NPV 85% (77% to 93%), AUC 80 % (75% to 86%) and accuracy 82% (75% to 88%). For conventional MRI, the sensitivity 74% (67% to 80%), specificity 77% (71% to 83%), PPV 62% (48% to 69%), NPV 70% (62% to 77%), AUC 78% (72% to 83%) and 71% accuracy (68% to 78%) was obtained. Conclusion: Based on our finding DCE-MRI is the most suitable technique for the discrimination of metastatic lymph nodes in rectal cancer.  相似文献   
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