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煤烟型大气污染对儿童肺功能的影响   总被引:4,自引:1,他引:3  
为观察煤烟型大气污染对儿童健康的影响 ,选择了太原市 3个污染程度不同地区的 45 0名儿童进行肺功能测试和问卷调查。研究结果显示 ,儿童呼吸功能表现为重度污染区 <中度污染区 <相对清洁区 ;肺通气功能阻塞性异常率表现为重度污染区 >中度污染区 >相对清洁区 ;Logistic回归分析发现肺通气功能阻塞性异常率与小学生家庭的取暖方式、厨房和卧室是否分开以及污染物的水平有关 ;多元线性回归分析显示重度污染区儿童的FVC、FEF5 0与相对清洁区相比分别减少了 65 80ml、119 2 7ml,中度污染区儿童的FVC、FEF5 0与相对清洁区相比分别减少了 5 7 2 8ml和 114 2 9ml;Ln(SO2 )每升高一个单位 ,FVC和FEF5 0分别减少69 10ml和 119 79ml,Ln(PM1 0 )每升高一个单位 ,FVC、FEF5 0等分别减少了 193 5 0ml和 171 69ml。结果提示 ,太原市煤烟型大气污染对儿童呼吸系统产生了危害。  相似文献   
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The geographic range of Zika virus (ZIKV) has expanded from Asia to the Americas, leading to the 2015–2016 pandemic with enhanced neurovirulence. At present, ZIKV is continuously circulating in many Southeast Asian countries. Unfortunately, the persistent evolution of ZIKV in Southeast Asia and its influence on the biological characteristics of the virus remain incompletely understood. In this study, the in vitro and in vivo properties of a new ZIKV isolate obtained from Cambodia in 2019 (CAM/2019) were characterized and compared with those of the Cambodian strain (CAM/2010). Compared with CAM/2010, the CAM/2019 virus showed similar plaque morphology and growth curves in cell cultures and induced comparable viremia and organ viral loads profiles in both BALB/c and A129 (IFNAR1−/−) mice upon intraperitoneal (i.p.) inoculation. Remarkably, the CAM/2019 virus exhibited enhanced neurovirulence in neonatal mice compared with CAM/2010, with a 74-fold reduction in the 50% lethal dose (LD50). Consistently, CAM/2019 produced higher viral loads in the brains of BALB/c neonatal mice than CAM/2010 did. Sequence alignment showed that the CAM/2019 virus has acquired 12 amino acid substitutions, several of which were found to be associated with neurovirulence. In particular, the CAM/2019 virus shared an A1204T substitution in NS2A with the Thai isolate SI-BKK02 that was isolated from a microcephaly case. Taken together, our results indicate that a ZIKV strain isolated with specific mutations has emerged in Cambodia, highlighting the need for extensive molecular and disease surveillance in Cambodia and other Asian countries.  相似文献   
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目的 分析我国消除丙型肝炎(丙肝)的普通人群HCV检测策略的成本效果,明确最佳成本效果的HCV检测年龄。方法 运用TreeAge pro 2019软件构建决策树马尔科夫模型,以1年为周期,模拟10万名20~59岁各年龄组人群HCV检测和治疗结果,以全社会角度分析策略间比较的成本效果和效益。效果指标为增量成本效果比(ICER),效益指标为净货币效益(NMB),以我国2022年人均国内生产总值(85 698元)为意愿支付阈值。通过单因素敏感性分析和概率敏感性分析评估结果可靠性。结果 在20~59岁人群HCV检测有成本效果,在40~49岁年龄组进行HCV检测成本效果最佳。20~59岁年龄组人群HCV检测策略与未HCV检测策略比较,增量成本为161.24元/人,增量效用为0.003 6质量调整寿命年(QALYs)/人,ICER为45 197.26元/QALY,ICER小于意愿支付阈值,具有成本效果。各年龄组人群HCV检测策略与未HCV检测策略比较,ICER为42 055.06~53 249.43元/QALY,NMB为96.52~169.86元/人,其中40~49岁年龄组的ICER最低,NMB最高。单因素敏感性分析结果显示,贴现率、丙肝抗体(抗-HCV)检测成本、人群抗-HCV阳性率和直接抗病毒药物治疗成本对经济学评价影响较大,但改变参数取值,结论不变。概率敏感性分析结果表明模型分析结果稳定。结论 医疗机构探索动员20~59岁普通人群进行HCV检测具有较好的成本效果,以40~49岁年龄组人群的HCV检测成本效果最佳。在我国普通人群中实施HCV检测的“愿检尽检”策略,能降低人群丙肝疾病负担。  相似文献   
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DNA免疫研究进展   总被引:2,自引:0,他引:2  
杨丽琛  杨晓光 《卫生研究》2006,35(1):110-114
DNA免疫可诱导机体全面的免疫应答,且与传统的蛋白免疫相比具有制作简单、经济安全、易于贮存运输等优点。自发现以来已越来越引起人们的重视,成为第三代疫苗,并广泛用于各种感染性疾病的防治研究中。作者主要综述DNA免疫作用机理,可能的影响因素,及其在抗体制备、婴儿免疫、粘膜免疫及表达文库免疫等方面的应用。此外,还介绍了增强DNA免疫效果的策略。  相似文献   
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Theoretically, a haplotype has a higher level of heterozygosity than individual single nucleotide polymorphism (SNP) and the association study based on the haplotype may have an increased power for detecting disease associations compared with SNP-based analysis. In this study, we investigated the effects of four haplotype-tagging SNPs (htSNP) and the inferred haplotype pairs of the X-ray cross-complementing group 1 (XRCC1) gene on chromosome damage detected by the cytokinesis-block micronucleus assay. The study included 141 coke-oven workers with exposure to a high level of polycyclic aromatic hydrocarbons and 66 nonexposed controls. The frequencies of total MN and MNed cells were borderline associated with the Arg(194)Trp polymorphism (P = 0.053 and P = 0.050, respectively) but not associated with the Arg(280)His, Arg(399)Gln and Gln(632)Gln polymorphisms among coke-oven workers. Five haplotypes, including CGGG, TGGG, CAGG, CGAG, and CGGA, were inferred based on the four htSNPs of XRCC1 gene. The haplotype CGGG was associated with the decreased frequencies of total MN and MNed cells, and the haplotypes TGGG and CGAG were associated with the increased frequencies of total MN and MNed cells with adjustment for covariates among coke-oven workers. This study showed that the haplotypes derived from htSNPs in the XRCC1 gene were more likely than single SNPs to correlate with the polycyclic aromatic hydrocarbon-induced chromosome damage among coke-oven workers.  相似文献   
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There is a lack of studies on the association between whole grain intake and cardiometabolic risk factors in China and the current definition of whole grains is inconsistent. This study defined whole grains in two ways, Western versus traditional, and examined their associations with the risks of major cardiometabolic factors (CMFs) among 4706 Chinese adults aged ≥18 years, who participated in surveys both in 2011 and in 2015. Diet data were collected by consecutive 3 d 24 h recalls, together with household seasoning weighing. Whole grains were defined as grains with a ratio of fiber to carbohydrate of ≥0.1, while coarse grains were defined as grains except for rice and its products, and wheat and its products. Multivariable logistic regressions were modeled to analyze the associations of intakes of whole grains and coarse grains, respectively, with risks of major CMFs including obesity-, blood pressure-, blood glucose- and lipid-related factors, which were defined by International Diabetes Federation and AHA/NHLBI criteria. After adjusting for potential confounders, the odds of elevated LDL-C decreased with the increasing intake levels of whole grains (OR 0.64, 95% CI 0.46–0.88, p-trend < 0.05). Moreover, adults with the whole grain intake of 50.00 to 150.00 g/day had 27% lower odds of overweight and obesity (OR 0.73, 95% CI 0.54–0.99) and 31% lower odds of elevated LDL-C (OR 0.69, 95% CI 0.49–0.96), as compared with non-consumers. In conclusion, given the significant nutrient profiles of whole grains and coarse grains, the adults with higher intakes of whole grains only may have a lower risk of LDL-C and overweight and obesity.  相似文献   
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随着人们对电离辐射对人类健康危害的认识,以及随之开展的电离辐射生物效应及防护措施的研究,逐步形成了放射卫生学。因此作为传统的公共卫生体系下的五大卫生之一,放射卫生主要围绕电离辐射对人体健康有害影响及其综合防护措施开展工作。从上世纪三、四十年代起,经过近百年的蓬勃发展,现阶段我国的放射卫生学学科水平和放射卫生工作成效等有了很大提升。本文就放射卫生学研究与我国放射卫生工作的历史、现状、工作内容等情况进行简单的概述,以期为我国放射卫生工作今后的发展提供助力。  相似文献   
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