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排序方式: 共有205条查询结果,搜索用时 31 毫秒
1.
A historical mortality study of a cohort of employees of a gold mining and refining company was carried out in Salsigne, France. A major goal of the study was to investigate the relationship between lung cancer mortality and exposure to arsenic, radon, silica, and other contaminants of the working environment. A twofold excess of lung cancer was found both among miners and smelters, mainly concentrated among workers who had experienced exposure to past levels of arsenic, radon, and silica. The consistency of the results in the mine and the refinery are suggestive of a carcinogenic risk from both soluble and insoluble arsenic, although the potential role of other factors cannot be dismissed. © 1994 Wiley-Liss, Inc.  相似文献   
2.
The burden of injuries is underestimated to an even greater extent in developing countries than in industrialized countries. The objective of this paper is to analyze injuries and diseases in the monitored work place of the world's largest tin mining operation in Yunnan, South China.  相似文献   
3.
有色金属矿山的井下氡积累与矿工肺癌   总被引:1,自引:0,他引:1       下载免费PDF全文
作者调查了湖南省4个有色金属矿,在1976-1981年间测定的井下平均氡子体浓度为现行限值的2-13倍,最高424倍;进行回顾性流行病学调查,其观察48125人年,肺癌PMR1.43-3.33,SMR3.46-11.50,氡致肺癌的相对危险增加系数每WLM为).010-0.057。矿上同时暴露于含砷矿尘,部分3.46-11.50,氡致肺癌的相对危险增加系数每WLM为0.010-0.057。矿上同…  相似文献   
4.
目的了解室内空气中氡的本底水平,找出氡的不同来源对室内的相对贡献。方法 REM-2型氡析出率仪对地面和墙壁表面进行氡析出的测量,利用FD-125氡钍分析仪对室内用水和煤气中氡的含量作了分析,探讨了太原市居室内空气中氡本底水平。结果室内氡主要是由土壤、建材中析出的,其次才是室外空气中氡的渗入,室内用水和煤气中氡贡献很小。结论根据调查结果,进行室内空气中氡对人体健康危害分析和剂量评价,建立了室内氡本底水平的数据库,为以后研究室内氡的防护措施提供了依据。  相似文献   
5.
Estimating the effects of small doses of ionising radiation on DNA is one of the most important problems in modern biology. Different cytogenetic methods exist to analyse DNA damage; the cytokinesis-block micronucleus assay (CBMN) for human peripheral blood lymphocytes is a simple, cheap and informative cytogenetic method that can be used to detect genotoxic-related markers. With respect to previous studies on radiation-induced genotoxicity, children are a poorly studied group, as evidenced by the few publications in this area. In this study, we assessed radon genotoxic effects by counting micronuclei (MN), nucleoplasmic bridges (NPBs) and nuclear buds (NBUDs) in the lymphocytes of children who are long-term residents from areas with high radon concentrations. In the exposed group, radon was found to cause significant cytogenetic alterations. We propose that this method can be employed for biomonitoring to screen for a variety of measures.  相似文献   
6.
7.
Purpose: To study polymorphic variants of repair genes in people affected by long-term exposure to radon. The chromosome aberration frequency in peripheral blood lymphocytes was used as the biological marker of genotoxicity.

Materials and methods: Genotyping of 12 single nucleotide polymorphisms in DNA repair genes (APE, XRCC1, OGG1, ADPRT, XpC, XpD, XpG, Lig4 and NBS1) was performed in children with long-term resident exposure to radon. Quantification of the aberrations was performed using light microscopy.

Results: The total frequency of aberrations was increased in carriers of the G/G genotype for the XpD gene (rs13181) polymorphism in recessive model confirmed by the results of ROC-analysis (‘satisfactory predictor’, AUC?=?0.609). Single chromosome fragments frequency was increased in carriers of the G/G genotype in comparison with the T/T genotype. In respect to the total frequency of aberrations, the G/G genotype for the XpG gene (rs17655) polymorphism was also identified as a ‘satisfactory predictor’ (AUC?=?0.605). Carriers of the T/C genotype for the ADPRT gene (rs1136410) polymorphism were characterized by an increased level of single fragments relative to the T/T genotype.

Conclusion: The relationships with several types of cytogenetic damage suggest these three SNP (rs13181, rs17655 and rs1136410) may be considered radiosensitivity markers.  相似文献   
8.
Abstract

Purpose: The aim of this study is to assess if there is a relationship between residential radon and lung cancer histological types and patients’ age at diagnosis.

Materials and methods: We conducted a multicenter hospital-based case-control study with eight participating hospitals. We included 216 never-smoking cases with primary lung cancer and 329 never-smoking controls. Controls were frequency matched with cases on age and sex distribution. Of them, 198 cases (91.7%) and 275 controls (83.5%) had residential radon measurements.

Results: Lung cancer risk reached statistical significance only for adenocarcinoma (Odds ratio [OR] 2.19; 95% Confidence interval [CI] 1.44–3.33), for other histologies the results were marginally significant. Residential radon level was higher for patients diagnosed before 50 and 60 years old than for older lung cancer cases.

Conclusions: Residential radon in never smokers seems to be a risk factor for all lung cancer histologies. Individuals diagnosed at a younger age have a higher residential radon concentration, suggesting an accumulative effect on lung cancer appearance.  相似文献   
9.
[目的]用多核细胞法研究氡及其子体诱发大鼠外周血淋巴细胞和气管-支气管上皮细胞的次黄嘌呤鸟嘌呤磷酸核糖转移酶(HPRT)基因位点突变情况。[方法]Wistar雄性大鼠24只,采用HD-3型多功能移动式氡室进行动态吸入染毒,按照氡染毒的累计暴露量,分为3个实验组和1个对照组;获取大鼠外周血淋巴细胞和气管-支气管上皮细胞,以多核细胞法检测该两种细胞的HPRT基因突变频率。[结果]大鼠外周血淋巴细胞和气管-支气管上皮细胞的HPRT基因突变频率均随氡累积暴露剂量的增加而相应增加,剂量-效应关系明显,拟合的函数分别为(?)=1.785×10~(-5)D~2 1.174×10~(-3)D 1.054和(?)=3.538×10~(-5)D~2 8.338×10~(-4)D 1.032。[结论]氡及其子体能诱发大鼠外周血淋巴细胞和气管-支气管上皮细胞的HPRT基因突变,呈现一定的剂量-效应关系。  相似文献   
10.
OBJECTIVES—To evaluate the relation between exposure to ground radon levels and leukaemia among children using existing population and disease registers.
DESIGN—Ecological correlation study.
SETTING—The county of Östergötland in Sweden.
METHODS—Every child born in the county between 1979 and 1992 was mapped to the property centroid coordinates by linking addresses in the population and property registers. Population maps were overlaid with radon maps and exposure at birth and each subsequent year was quantified as high, normal, low or unknown. This was analysed with data from the tumour registry. Standardised mortality ratios (SMRs) were calculated using the age and sex specific rates for Sweden for the year 1995.
RESULTS—90 malignancies occurred among 53 146 children (498 887 person years) who formed the study population. SMRs for acute lymphatic leukaemia (ALL) among children born in high, normal and low risk areas were 1.43, 1.17 and 0.25 respectively. The relative risk for the normal risk group and high risk group as compared with the low risk group was 4.64 (95% CI 1.29, 28.26) and 5.67 (95% CI 1.06, 42.27). The association between ALL and continued residence at normal or high risk areas showed a similar trend. No association between radon risk levels and any other malignancy was seen.
CONCLUSION—Children born in and staying at areas where the risk from ground radon has been classified as low are less likely to develop ALL than those born in areas classified as normal and high risk.


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