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FT Chew  DYT Goh  BC Ooi  R Saharom  JKS Hui  BW Lee 《Allergy》1999,54(4):320-329
BACKGROUND: Air-pollution levels have been shown to be associated with increased morbidity of respiratory diseases. METHODS: Data for ambient air-pollutant levels, meteorologic factors, and hospitalization or emergency room (ER) visits for acute asthma in Singapore children over a 5-year period (1990-4) were obtained and analyzed for associations by time-series methods. RESULTS: Throughout this period, the annual mean and 24-h mean levels for sulfur dioxide (SO2), nitrogen dioxide (NO2), and total suspended particles (TSP) and maximum 1-h daily average for ozone were generally within the air-quality guidelines established by the World Health Organization (WHO). However, positive correlation between levels of each of these pollutants and daily ER visits for asthma was observed in children aged 3-12 years, but not among adolescents and young adults (13-21 years old). The association with SO2 and TSP persisted after standardization for meteorologic and temporal variables. An adjusted increase in 2.9 ER visits for every 20 microg/m3 increase in atmospheric SO2 levels, lagged by 1 day, was observed on days when levels were above 68 microg/m3. With TSP, an adjusted increase of 5.80 ER visits for every 20 microg/m3 increase in its daily atmospheric levels, lagged by 1 day, was observed on days with levels above 73 microg/m3. Similar results were also obtained after controlling for autocorrelation by time-series analysis. CONCLUSIONS: These associations were observed even though the overall levels of all pollutants were generally within the air-quality guidelines established by the WHO. These findings suggest that asthmatic children are susceptible to increased levels of air pollutants, particularly SO2 and TSP, although the ambient levels are generally within "acceptable" ranges.  相似文献   
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Stakeholders engaged in funding health programs and investing in human capital are concerned that their investments lead to beneficial long-term outcomes and do not fade from existence when funding streams dry up. However, dissemination and implementation researchers often pay little attention to what happens after programs are implemented. An essential function of the public health nurse operating at the executive management or leadership level is to evaluate overall effectiveness, quality, and sustainability of programs and to design systems-level quality initiatives and evaluation plans that foster program sustainability. This article applies a conceptual framework for sustainability to an oral health program serving persons experiencing homelessness, exploring the essential programmatic, community, and organizational factors that have positively impacted the long-term sustainability of the program. Lessons learned from a model program that has thrived in a political and economic resource poor climate may assist the public health nurse in planning and developing health programs that can withstand the test of time even in the most challenging of circumstances.  相似文献   
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