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101.
利用岩石类型资料1092个数据,肝癌死亡调查资料1544例,研究了肝癌死亡率与人群生存区的岩石类型(岩浆岩、变质岩、碳酸盐岩、碎屑岩、红色碎屑岩、第四系松散岩)的相关性。在此基础上,综合评价了与肝癌有相关性的岩石类型对肝癌的产生和发展的影响。  相似文献   
102.
Prolonged exposure to any level of radon in indoor air is generally thought to be hazardous to human health and to give rise to lung cancer. On the other hand, low or moderate levels of radon in indoor air may, according to the radiation hormesis hypothesis, be beneficial to human health and even inhibit the growth of cancerous cells. An attempt is made here to test these contrasting views by comparing mortality rates from lung cancer during the 10-year period 1986–1995 with average indoor radon levels in the 435 communes (municipalities) of Finland (excluding Åland). The results show a very low, statistically non-significant correlation between radon and lung cancer mortality (r=–0.0331), which in turn implies that at least in this case neither the possible beneficial hormetic effect of radon nor its cancer-provoking hazardous effect can make itself apparent against the dominant and masking effect of cigarette smoking, the main cause of lung cancer.  相似文献   
103.
Previous studies have found that mean-residential-radon (Rn) levels for U.S. counties are negatively associated with age-adjusted county rates of lung-cancer mortality (LCM), after adjustments for potentially confounding factors. Those results may be due to (a) confounding unaddressable by any county-level (ecological) study design, or (b) county-level factors such as Rn/smoking or age/radon correlations or exposure misclassifications from the use of disparate data sources. Possibilities (b) were addressed by comparing age-specific LCM rates for white women in 2821 U.S. counties who died in 1950–54 at age 40+ (11% of whom ever smoked), or at age 60+ (% of whom ever smoked), to county Rn levels newly estimated from U.S. Rn, climatic and geological-survey data. Significant negative LCM v Rn trends were found for both age groups, after adjusting for age and subsets of 21 county-level socioeconomic, climatic and other factors. Negative trends were largest for counties with 100 Bq m–3 Rn (p 0.00087; 420 analyses). Adjusted relative risk (RRadj) for LCM was significantly elevated (1 < [95% conf. limits on RRadj] 1.46) in 43 of 210 analyses comparing LCM rates in counties with > 150 Bq m–3 v 65–100 Bq m–3 Rn, most involving adjustment for climate- and education-related factors likely to have influenced exposure to indoor air contaminants such as Rn and cigarette smoke. Though inconclusive due to potential ecological-fallacy-related confounding that could not be controlled, results from this ecological study are most consistent with a U-shaped dose-response relationship between 1950–54 LCM risk and U.S. residential radon in white women who predominantly never smoked.  相似文献   
104.
总N—亚硝基化合物接触量与胃癌死亡率的生态学相关性   总被引:2,自引:0,他引:2  
吴永宁  王绪卿 《环境化学》1997,16(2):125-129
在胃癌高发区福建省长乐县和低发区山东省崂山县和随机选择近60名35-64岁男性一,以份饭法收集24h膳食和12h尿液,测定总N-亚硝基人合物(TNOC)含量,计算膳食摄入量和尿中排出量人群日均膳食摄往我为7.074.31μmol,低发区为4.07±3.67μmol,P〈0.001;12h尿中排出量高发区为113±0.61μmol,低发区为0.34±0.27μmol,P〈0.001;尿中排出量与膳食  相似文献   
105.
利用江西省大量岩石类型和食管癌死亡调查资料,对食管癌死亡率与人群生存区岩石类型的相关性进行了研究。结果表明,江西省食管癌死亡率与岩石类型密切相关。食管癌死亡率与变质岩、碳酸盐岩、第四系松散岩、红色碎屑岩呈正相关,与岩浆岩呈负相关,与碎屑岩相关不显著。  相似文献   
106.
Toxic effects can be induced in experimental animals by high doses of pure PCBs, and in man by PCDF-contaminated PCB. In order to assess the effects of ordinary, uncontaminated PCB on man, a group of capacitor workers who had direct occupational exposure to Aroclors 1254, 1242, and 1016 during the period 1946 to 1977 has been under medical surveillance since 1976. This group presented some indications of non-AhR-mediated microsomal enzyme induction during the period of direct exposure, but no chloracne or increased cancer mortality. Multiple regression studies revealed no significant associations between lipid PCB levels and clinical indicators of hepatotoxicity, hypertension, or pulmonary impairment.  相似文献   
107.
利用中国癌死亡率与土壤环境中化学元素的相关性研究成果,研究了内蒙古宫颈癌死亡率与土壤环境中化学元素:Hg、Pb、Na、K、Mg、Ca、Sr、B、Tm、Th、U、Sn、Hf、Bj、Ta、Te、Mo、Br、I等19个元素含量的关系。  相似文献   
108.
在北京中心城区(北2~3环路)利用大流量颗粒物采样器连续采集了2016年全年共218个PM2.5样品,通过电感耦合等离子体原子发射光谱法(ICP-AES)测定了其中9种重金属元素,即As、Cd、Co、Cr、Cu、Ni、Pb、V、Zn.结合我国人群暴露参数,利用美国环保署推荐的健康风险评价模型,对北京市1~80岁不同年龄人群致癌非致癌健康风险进行了评价.结果显示:2016年北京市PM2.5重金属中Zn、Pb、Cu质量浓度最大,依次为(291±553)ng/m3、(53.6±73.5)ng/m3、(25.0±59.7)ng/m3,其次为As、Ni;所有重金属中,As具有最大致癌风险贡献(62.5%),Co具有最大非致癌风险贡献(29.0%).不同年龄、性别人群的重金属危害指数(HI)均小于1,显示无非致癌健康风险,另外,儿童期HI值大于成人期.不同年龄、性别人群的重金属总致癌风险(CR)均位于10-6与10-4范围(即每1万~100万的人群数量中增加1个癌症患者),显示无显著致癌风险,另外,随着年龄的增长致癌风险增加.此外,同一年龄人群中,女性致癌及非致癌风险均稍低于男性.  相似文献   
109.
利用土壤环境资料中关于锡元素的32335个数据,癌死亡调查资料787080例,研究了胃癌、食管癌、肝癌、宫颈癌、肺癌、大肠癌、白血病、鼻咽癌、乳腺病死亡率与人鲜生活区土壤环境中锡元素的关系,结果表明。食管癌死亡率与生活区土壤中锡元素质量分数的相关性显著,肝癌、宫颈癌、鼻咽癌死亡率与生活区土壤中锻元素质量分数的相关性极显著,而胃癌、肺癌、大肠癌、白血病、乳腺癌死亡率与生活区土壤中锡元素质量分数的相共性下显著。  相似文献   
110.
Breast cancer is the most common cancer in women. Therefore, there is an urgent need to identify and develop therapeutic strategies against this deadly disease. This study is the first to investigate the cytotoxic and apoptotic effects of Scrophularia oxysepala in MCF-7 human breast cancer cells. Dichloromethane, methanol and n-hexane extracts of Scrophularia oxysepala were examined. The 3-(4,5-dimethylethiazol-2-yl)-2,5-diphenyltetrazolium (MTT) reduction and trypan-blue exclusion assays were performed in MCF-7 cells as well as control cell line MCF10A to analyze the cytotoxic activity of the plant. Furthermore, the apoptosis-inducing action of extracts of the plant was evaluated using cell death detection ELISA, the terminal deoxynucleotide transferase dUTP nick end labeling (TUNEL) assay, Western blotting and real-time polymerase chain reaction (PCR). The results showed that dichloromethane and methanol extracts significantly inhibited cell growth and viability without inducing damage to MCF10A cells. Cell death detection ELISA, morphological changes of cells in TUNEL assay, Western blot detection of poly (ADP-ribose) polymerase (PARP) cleavage and increase in the mRNA expression levels of p-53, caspase-3 and c-myc showed that the induction of apoptosis was the main mechanism of cell death. Our results strongly suggest that this plant may contain potential bioactive compound(s) for the treatment of breast cancer.  相似文献   
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