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The objective of this paper was to assess the link between premature mortality and a combination of neighbourhood contextual (environmental and health) and compositional (socioeconomic and demographic) characteristics. We statistically and spatially examined six environmental variables (ultrafine particles, carcinogenic and non-carcinogenic pollutants, pollution released to air, tree cover, and walkability index), six health service indicators (number health providers, breast, colorectal and cervical cancer screening uptake rates, student nutrition program uptake rates, and healthy food index), and eight socioeconomic indicators (total income, Gini coefficient, two age categories – below and above 40 years, proportion of females to males, visible minorities, Indigenous peoples, education, less than grade 9) among 140 neighbourhoods of the City of Toronto in Ontario (Canada). We applied principal component analysis to identify patterns and to reduce the number of explanatory variables into combined component axes that represent unique variation in these confounded and overlapping factors. We then applied regression analysis to model the relationship between the indices of enviro-health and socioeconomics and their potential relationship with premature mortality. Residual spatial analysis was used to investigate any remaining spatial structure (such as neighbourhoods with higher residual premature mortality rates). Neighbourhood Equity Index was correlated with our enviro-health and socioeconomic indices. Premature mortality within neighbourhoods was predicted by poor cancer screenings, pollution, lack of tree canopy, increased uptake of student nutrition programs and high walkability index. A negative association between premature mortality and pollution was associated low walkability index and presence of visible minorities within neighbourhoods. There was some unexplained residual spatial variation in our model of premature mortality - especially along the shores of Lake Ontario and in neighbourhoods with major highways or road corridors: premature mortality in Toronto neighbourhoods was higher than expected along highway-corridor neighbourhoods and shorelines. Our analysis revealed a significant relationship between neighbourhood contextual features – both environmental and health – and premature mortality, suggesting that these contextual components of neighbourhoods can predict rates of urban premature mortality in Toronto.  相似文献   
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高中一年级学生抑郁情绪及相关因素的研究   总被引:1,自引:0,他引:1  
目的调查高中一年级学生的抑郁情绪及与其个性、心理健康水平、应对能力和家庭环境的关系。方法采用整群抽样方法和问卷式调查,共调查高一学生488名,资料填写完整者449人(92.01%)。结果449名高一学生SDS平均得分(标准分)为(47.27±10.86),抑郁情绪的发生率为37.86%,不同性别和文理科之间差异无统计学意义。抑郁情绪组性格内向、情绪稳定性差和精神质表现较为突出,其SCL-90的9个因子评分均高于对照组,个人积极应对能力和解决问题的能力差,消极应对和自责表现突出,家庭的亲密度、情感表达、娱乐性和组织性均较对照组差,矛盾性较对照组突出。结论抑郁情绪已是高一学生中较为常见而且需要关注的心理卫生问题,严重影响其心身健康发展,抑郁情绪与个性、心理健康评分、个人应对方式和家庭环境均具有显著关系。  相似文献   
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BACKGROUND: Exposure to a high level of house dust mite allergens (HDMAs) is considered as a risk factor for HDM sensitization and development of asthma in genetically disposed people. Mattresses are one of the most important sources of HDMA in people's living environment. OBJECTIVE: The aim of this study was to evaluate the association between mattress characteristics and HDMA concentrations on mattresses. METHODS: Dust samples of mattress surfaces were taken to evaluate the level of Der p 1 allergen. All participants filled in a questionnaire about the type of mattress, the type of covering (upper layer) of the mattress, dwelling characteristics and cleaning habits. Humidity and temperature of the bedroom were measured at the time of dust sampling. RESULTS: One hundred and sixty-eight questionnaires were filled in. Synthetic upper layer of the mattress was associated with a higher level of Der p 1 compared with cotton upper layer (2.6 vs. 0.8 microg/g Der p 1). Moreover, higher relative humidity (RH) was associated with significant higher concentrations and density of Der p 1. CONCLUSIONS: Two factors were associated with lower levels of Der p 1 found on mattresses, namely: a cotton upper layer of the mattress compared with a layer of synthetic material and lower RH at the time of sampling. As far as we know, the association between type of upper layer and concentration of Der p 1 has not been described before and could lead to the formulation of practical advices in order to reduce HDMA concentrations on mattresses.  相似文献   
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学习成绩、家庭环境对学龄儿童自我意识的影响   总被引:2,自引:1,他引:1  
目的探讨学习成绩、家庭环境对儿童自我意识的影响。方法采用经验评估法、家庭环境量表和Piers Harris儿童自我意识量表对 9.5~ 12岁 2 87名儿童的学习成绩、家庭环境和自我意识进行评定。结果自我意识总分学习困难组 ( 5 8.76± 11.0 1) <学习中等组 ( 64 .5 9± 7.87) <学习优秀组 ( 69.80± 7.5 1) ,家庭环境量表中的亲密度、情感表达、矛盾性、知识性、娱乐性和控制性 6个因素与自我意识相关。结论学习成绩、家庭环境对学龄儿童自我意识的形成和发展起重要的作用 ,改善家庭环境、提高学习成绩 ,可有利于儿童自我意识的发展。  相似文献   
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Familial risk of cancer among randomly selected cancer probands   总被引:1,自引:0,他引:1  
Several investigators have reported that relatives of lung cancer probands have a greater-than-normal likelihood for developing some form of cancer. To evaluate whether this familial risk is general for probands with cancer at any site or limited to lung cancer probands, we did a case-control study in which probands having cancer affecting any body site were identified and their pedigree data were tabulated. Telephone interviews and a mailed questionnaire were used to obtain cancer histories and environmental exposures on the families of 41 lung cancer probands, 105 probands with cancer other than lung, and 127 spouse families. Cumulative tobacco exposure (P less than .05), occupational hazards (P less than .005), and age of the family relatives (P less than .0001) were found to be statistically significant predictors of cancer risk. With consideration given for these variables, we determined that siblings of lung cancer probands were at slightly greater risk of cancer of any kind (odds ratio [OR] = 1.43, P = .06) than siblings in the control group. Much of the elevated risk was attributable to an excess of lung cancer (OR = 2.49, P = .06). Siblings of non-lung/non-breast cancer probands were also determined to be at increased risk of lung cancer as well (OR = 1.61, P = .06). For parents, the risk was lower, although parental information may have been underreported.  相似文献   
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本文报告热习服对血浆丙二醛和中分子物质含量的影响。15名健康男子,平均年龄21.8±0.7岁,于平均气温27.3±1.2℃负重行军90min,2周内共锻炼11次(天)。标准热暴露试验对比表明获得了热习服,肛温和心率增值大大降低(P<0.01和P<0.05)。锻炼期前、后标准试验时血浆丙二醛含量降幅分别为29.4%(P<0.01)和30.1%(P<0.01),而中分子物质含量增幅分别为6.3%(P<0.05)和9.2%(P<0.01)。热前、后血浆丙二醛含量较锻炼期前仅分别降低5.5和6.5%(P>0.05),而中分子物质含量分别降低18.3和16.1%(P<0.01),可见,热习服后血浆丙二醛和中分子物质含量没有同步降低。  相似文献   
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