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321.
本文集中在横向分析近期波兰儿童铅暴露和铅暴露增加背后的社会经济因素。在上西里西亚工业区,铅是分布最广泛的有毒重金属之一。儿童血铅水平升高关系儿童幸福,不断引起严重关切。本研究涉及在1999 - 2013年间,上西里西亚地区3岁到18岁的4 882名儿童。记录了每一个孩子血液中铅的浓度。孩子的父母被要求回答关于儿童接触铅的环境和家庭社会经济条件的问卷调查。铅暴露增加的因素包括:父母受教育程度较低,父母失业、父母的职业铅暴,家庭的贫穷社会经济地位,在家吸烟,生活在建筑物底层,食用本地种植的蔬菜和水果,在污染环境中长期进行户外活动和男性性别。铅的环境暴露仍然是导致上西里西亚地区儿童慢性铅中毒的主要因素。与儿童血铅浓度关系最大的社会经济因素是儿童父母的低教育水平。
精选自Wojciech Pelc, Natalia Pawlas, Micha? Dobrakowski, S?awomir Kasperczyk. Environmental and socioeconomic factors contributing to elevated blood lead levels in children from industrial area of Upper Silesia. Environmental Toxicology and Chemistry: Volume 35, Issue 10, pages 2597–2603, October 2016. DOI: 10.1002/etc.3429
详情请见http://onlinelibrary.wiley.com/doi/10.1002/etc.3429/full
  相似文献   
322.
To evaluate the effects of fluoride on the kidney and the liver of ICR-derived glomerulonephritis (ICGN) mice by using laboratory tests and pathological examinations, fluoride was administered to the ICGN mice at 0, 25, 50, 100, and 150?ppm in drinking water for 4 weeks and to the ICR mice, which have normal kidney function at 0 and 150?ppm. The BUN, creatinine, GOT, and GPT in the serum of each mouse were determined. When a mouse died, the sample from the day closest to the death was assigned for the mean. Pathological changes in the kidney were examined after PAS (periodic acid-Schiff) staining. All of the ICGN mice in the 150?ppm group and one of seven in the 100?ppm group died before the end of week 4, but no ICR mice died. For ICGN mice, the mean value of body weight in the 150?ppm group was significantly lower than those in 0?ppm group and other fluoride-administered groups. The mean values of relative liver and kidney weights in the 100 and 150?ppm groups were significantly lower than those in the control. The mean values of BUN, creatinine, and GPT in the 150?ppm group were significantly higher than those in the control. The thickness of the glomerular capillary wall and the increased mesangial matrix in the kidney were prominent in the fluoride-administered ICGN mice. These results suggested that fluoride severely exacerbated glomerulonephritis and tublar-intestitial changes in ICGN mice.  相似文献   
323.
It is well known that lead (Pb) produces reduced haemoglobin (Hb) levels and risk of anemia when blood lead levels (BPb) are greater than 20?µg?dL?1. Two recent studies reported an increased risk of anemia in children with BPb between 10–20?µg?dL?1, but few studies examined the association between Hb levels or risk of anemia and BPb under 10?µg?dL?1. In the present study this association was examined using data of 140 preschool children from a larger prospective cohort study in China. Data showed that compared to children with BPb <5?µg?dL?1, children with BPb between 7.5–10?µg?dL?1 had significantly lower Hb levels, but there were no marked differences for other groups. A linear regression model showed a negative relationship between BPb and Hb levels after controlling for age, gender, height, weight, and iron (Fe) deficiency. This finding, although limited by a small sample size, suggests it may be important to examine Pb-induced hemosynthesis effect at concentrations less than 10?µg?dL?1.  相似文献   
324.
Previous lead (Pb) exposure studies identified the Michelena sector in Valencia as a ‘critical’ area for Pb contamination. An analytical-ecological study was designed to evaluate the association of environmental and nutritional variables with blood lead (BPb) in children attending two schools located in this sector. A questionnaire was administered and the findings were correlated with BPb and serum-calcium (S-Ca) levels. The total population examined included 60 children (4–9 years old). The mean BPb values was 10.5?±?3?ug/dL (61.7%?≥?10?ug/dL) and the mean S-Ca was 8.9?±?0.7?mg/dL. A significant difference (p?=?0.042) was found between BPbs in males (11.1?±?3.1?ug/dL) when compared with females (9.6?±?2.8?ug/dL). Child age, school, schedule at school, parents' occupational exposure, habits, and socioeconomic status had no significant association with BPbs. The relationship between BPb levels (dependent variable) and the S-Ca and daily Ca intake levels (independent variables) was analysed through multiple regression analysis. The results show an inverse relationship between BPb and both variables (β?=??0.073, and β?=??0.001) respectively, with the daily Ca intake being the only significant variable in the model (p?=?0.04). Although average BPbs was not very high, the percentage of children with BPbs higher than the US-CDC intervention level was greater than those found in other studies. Since detailed information is generally unavailable for these children in Venezuela, this study provides insights for future research.  相似文献   
325.
Previous studies suggested environmental exposures, including mercury (Hg) and lead (Pb), may be related to Wegener's granulomatosis. In this study, investigations were extended to include the measurement of heavy metals in blood samples from patients diagnosed with Wegener's. Diagnosis was confirmed by using the 1990 Classification Criteria for Wegener's granulomatosis established by the American College of Rheumatology (ACR). Using commercial lab testing, whole blood heavy metal screenings were obtained from patients, and results were then compared with validated subject self-report questionnaire estimates of exposure. Thirty-eight Wegener's patients were enrolled; 10 of the 38 exhibited abnormal lab values. In those 10 subjects 3 had elevated nickel (Ni), 7 with increased cobalt (Co), 3 with higher manganese, 1 with elevated copper, and 1 with increased Hg. Overall, the questionnaire results did not correlate with the blood heavy metal analysis. Approximately 26% of Wegener's subjects in this study displayed abnormal heavy metal levels. These findings are likely underestimates since blood levels are an insensitive means for assessing total body burden of heavy metals. From these preliminary studies it appears that elevated Co is a common finding in Wegener's patients but Ni and Hg were also found to be increased. The proportion of patients with abnormal heavy metal levels is more than expected by chance alone. In order to yield more definitive results, further analysis is needed with a larger data set, more controls and more sensitive measurements (hair, urine, or nail samples).  相似文献   
326.
Effects of synthetic pyrethroid insecticide α-cypermethrin were investigated following intradermal dose (5–50 mM) of cypermethrin to male albino Wistar rats. Glucose, protein, cholesterol, triglycerides, urea, uric acid, creatinine, hemoglobin, blood RBC, and WBC content were determined 6 h after pesticide administration. Biochemical parameters and blood cell count changed significantly in treated rats at all doses. Low-dose cypermethrin affected early biochemical changes in rats.  相似文献   
327.
生物节律理论在铁路行、调车安全中的应用探讨   总被引:1,自引:1,他引:0  
首先对生物节律理论的涵义以及相关专业论文著作中对临界日的主要观点进行了概述。通过对生物节律理论的研究,提出了扩大范围的"72小时临界期"作为统计样本数据的依据。经过对37个样本的统计分析得出,对于铁路行、调车工种情绪高潮期是危险多发阶段,并归纳出"低低高、高高高、临低高、低高高"四类针对行、调车工种的"特别危险"级别的生物节律组合,然后使用四起一般事故作为以上分析结果的佐证。给出了生物节律在行、调车安全生产中应用的四项建议。最后,得到生物节律技术是对传统安全管理方法补充的结论。  相似文献   
328.
不同地域环境孕妇血硒水平的研究   总被引:2,自引:0,他引:2  
丹东市、聊城市、晋城市土壤含硒量分别是0.106±0.09、0.113±0.08、0.09±0.007mg/kg,属于缺硒生态景观;温州市土壤,面粉含量分别是0.188±0.01、20.026±0.014mg/kg属于中等硒含量生态景观。各城镇孕妇血硒含量依次为112.2±48.5(54例)、113.7±63.4(32例)、96.0±48.1(44例)、130.6±60.6(59例)μg/L。生态景观硒含量最高的温州市孕妇血硒含量高于缺硒生态景观的城镇。  相似文献   
329.
大连市肿瘤发生率与居民血硒水平的研究   总被引:4,自引:0,他引:4  
采用新极谱法测定大连市健康居民300例和癌症患者50例全血的硒含量,分别为146.5±51.0μg/L(148.1±50.2μg/L和144.7±51.9μg/L)和122.7±55.9μg/L是正态分布类型,均小于我国低硒地区160μg/L是  相似文献   
330.
应用人体外周血淋巴细胞微核试验测定了29种取代苯酚类化合物的遗传毒性(72h-lgMN20),并对此类化合物的遗传毒性大小进行了分析比较,同时构建了遗传毒性与分子结构参数之间的QSAR 模型.结果表明,29种取代苯酚类化合物都显著地导致了微核的产生,具有明显的遗传毒性;遗传毒性大小与取代官能团及官能团位置存在一定的规律;遗传毒性的大小与分子结构参数溶剂连接性指数(X2SOL)、自由基信息参数(ICR)、零阶平均分子连接性指数(X0A)及修正指数(LOP)之间存在良好的结构-活性相关关系,所建模型的相关系数r2= 0.816,可以用于定量评估其它取代苯酚类化合物的遗传毒性.  相似文献   
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