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91.
An investigation was conducted to identify high-risk industries for histological subtypes of lung cancer based on a large population-based case-control study in British Columbia, Canada. Occupational histories and information on smoking and relevant covariates were collected from 14,755 male incident cancer cases. Industrial risk factors for 2998 lung cancer cases, including histological subtypes were assessed by logistic regression using other cancer cases, excluding smoking-related cancers, as controls. An excess risk of lung cancer was found among workers in mining, metal manufacturing, and electric power systems for all histological-subtypes, and construction, water transport, health services for specific histological subtypes. Industrial associations that are unique to histological subtypes of lung cancer were identified. Future research needs to focus on confirming these histological associations, and identifying the risk from key exposures found within these industries (e.g. medical radiation, electromagnetic fields, and cooking fumes).  相似文献   
92.
The pulmonary Cd and Cr content was determined from 53 lung cancer patients operated for cancer and from 39 patients who died of non‐malignant diseases. The results were correlated with smoking habits, pulmonary emphysema and occupational history. Both the pulmonary Cd and Cr increased with the amount of smoking. In ex‐smokers the Cr content in lung tissue did not diminish with the time since stopping smoking, but the Cd did follow the half‐life of about 9 years. The pulmonary Cd, compared with smoking habits, behaved similarly in both the lung cancer and control patients, whereas Cr in the lung cancer patients could not be explained solely by smoking, but some of the cancer patients may have been occupationally exposed to Cr. Speciation was not studied.  相似文献   
93.
94.
Mixed exposures to a number of metallic compounds may give rise to a carcinogenic response in humans.

An interaction between occupational exposure to arsenic and cigarette smoking has been documented epidemiologically. A multiplicative effect was indicated concerning the occurrence of lung cancer when both of the exposures were present. Several experimental studies have been reported in the literature concerning interactions between benzo(a)pyrene and Fe2O3 as well as some other metallic compounds like Ni3S2, PbO, MgO and TiO2 in relation to respiratory carcinogenicity. There is also limited evidence of a positive interaction between arsenic trioxide and benzo(a)pyrene. Particles containing V and Ni were obtained from the flue gases of power plants burning heavy fuel oil. Such particles were not carcinogenic themselves but enhanced the carcinogenicity of benzo(a)pyrene even more efficiently than Fe2O3.

Increased dietary selenium intakes can decrease the carcinogenicity of several organic carcinogens in animals and dietary zinc can effectuate both enhancement and inhibition of carcinogenicity depending on dietary concentration.  相似文献   
95.
目的 研究姜黄素对IGF-1调控的宫颈癌淋巴转移动物模型的研究.方法 建立宫颈癌淋巴转移鸡胚尿囊膜(CAM)模型,并观察姜黄素对IGF-1调控的淋巴管生成的作用.结果 ①在健康受精的SPF鸡胚的CAM上接种不同浓度的Hela细胞悬液1×103/L~1×108/L存活率差异没有统计学意义.1×107/L为最适接种浓度.②移植瘤组织切片HE染色课件癌细胞聚集成癌巢,与人宫颈癌形态相似.免疫组化染色,可见移植瘤内有微淋巴管形成③对照组、IGF-1组、Cur组和IGF-1+ Cur组的LMVD依次为21.28±10.13、28.58±12.26、16.23±8.76和18.23±9.36条/4HP,LVA依次为2.91±1.16、3.42±1.25、2.00±1.51和2.72±1.21%,差异具有统计学意义(P<0.05).结论 在鸡胚人宫颈癌移植瘤模型中可观察到姜黄素对IGF-1调控的宫颈癌淋巴管生成的抑制作用.图3,表3,参9.  相似文献   
96.
福建省稻米中的砷水平及其健康风险研究   总被引:1,自引:0,他引:1  
为更好了解区域水平上水稻(OryzasativaL.)砷所引起的健康风险,在福建省9个地区采集了206份水稻样品并对其总砷和无机砷含量进行了分析,然后在此基础上建立风险评价模型并对其健康风险进行了评价。结果表明,福建省水稻精米中总砷平均含量为(0.105±0.091)mg·kg-1,无机砷平均含量为(0.045±0.019)mg·kg-1。全省所有样品中无机砷含量符合中国国家标准规定的限量标准(MCL)0.15mg·kg-1。通过膳食调查的数据和水稻无机砷含量对每天通过稻米消费无机砷摄入量进行了计算,全省平均每天无机砷摄入量为13.50μg,并且9个地区每天无机砷摄入量均超过了美国国家研究委员会所规定的最大限量标准10μg·d-1。根据无机砷摄入量和癌症斜率因子所构建的癌症风险模型结果表明,福建省稻米无机砷所引起的癌症风险为每100000有37.5人,虽然低于中国的平均水平(每100000有61人),但是超过了美国国家环境保护局所规定的可以接受的癌症风险的上限(每100000人有10人)。因此,需要进一步通过流行病学方面的调查来确定福建省稻米无机砷摄入和健康风险之间的关系。  相似文献   
97.
北京某小学室内外VOC浓度及有毒害物种识别   总被引:2,自引:2,他引:0  
黄山  邵敏  陆思华 《环境科学》2008,29(12):3326-3330
采用美国EPA推荐的TO14/15方法定量分析了北京市某小学室内外夏季观测的空气样品,得到82种挥发性有机物(VOCs)的浓度水平及组成特征,对其中可能危害儿童健康的有毒有害物质进行了识别.结果表明,室内总VOCs浓度高于室外,烷烃是含量最丰富物种,平均占室内外空气中定量VOCs总浓度的32.8%.室内外VOCs组成相似,异戊烷、苯、甲苯、丙醛、丙烯和二氯甲烷为浓度优势物种,受到室外源的影响较大,室内的对二氯苯、环己烷及间二氯苯较为特征,前2种物质室内/室外浓度比例平均值分别为65.8和10.5,间二氯苯室内平均浓度为2.02×10-9(体积分数),而室外浓度低于检测限,这3种物质可能来自室内源. 1, 3-丁二烯、氯乙烯、苯和氯甲烷4种物质在学校室内、室外及儿童家中都超过1×10-6的癌症风险值,平均风险值分别为1.3×10-5、 6.4×10-6、 5.1×10-6和3.3×10-6,小学室外、室内及儿童家中的累积癌症风险超过1×10-6的癌症风险值24~39倍.丙烯醛未确认具有致癌性,但具有毒有害性,在室内外及儿童家中超过基准浓度13~72倍.  相似文献   
98.
In birds and mammals, the thyroid gland secretes the iodothyronine hormones of which tetraiodothyronine (T4) is less active than triiodothyronine (T3). The action of T3 and T4 is calorigenic and is involved in the control of metabolic rate. Across all vertebrates, thyroid hormones also play a major role in differentiation, development and growth. Although the fish thyroidal system has been researched extensively, its role in thermogenesis is unclear. In this study, we measured overall heat production to an accuracy of 0.1 mW by direct calorimetry in a free-moving European eel (Anguilla anguilla L.) with different thyroid status. Hyperthyroidism was induced by injection of T3 and T4, and hypothyroidism was induced with phenylthiourea. The results show for the first time at the organismal level, using direct calorimetry, that neither overall heat production nor overall oxygen consumption in eels is affected by hyperthyroidism. Therefore, we conclude that the thermogenic metabolism-stimulating effect of thyroid hormones (TH) is not present with a cold-blooded fish species like the European eel. This supports the concept that TH does not stimulate thermogenesis in poikilothermic species.  相似文献   
99.
本文旨在检测健康人群与前列腺癌患者血清中重金属锑的含量,并对重金属锑在前列腺癌发生发展中的作用和相关机制进行初步探索。本实验使用电感耦合等离子体质谱仪(ICP-MS)对健康人群和前列腺癌患者血清中重金属锑的含量进行了检测;此外,分别通过MTT和Alamar-Blue方法对于重金属锑对人前列腺癌PC-3细胞的毒性效应进行了评价,并进一步探讨了非毒性剂量的重金属锑对前列腺癌细胞增殖能力(细胞计数及克隆形成实验)及脂类代谢过程(细胞内甘油三酯)的影响。研究结果显示:重金属锑在前列腺癌组患者血清中含量明显高于健康人群组且差异具有统计学意义;毒性实验结果表明高剂量的重金属锑能够显著抑制细胞活力且呈浓度依赖型方式,而非毒性剂量重金属锑能够显著促进前列腺癌细胞增殖,并导致细胞内甘油三酯的含量增加(P0.05)。综上所述,重金属锑在前列腺癌患者血清中具有相对较高水平,其机制可能是通过影响细胞脂类代谢从而促进前列腺癌的进展,这将对未来前列腺癌的预防和治疗提供一定的理论依据。  相似文献   
100.
福建省胃癌高发区环境地质、地球化学特征分析   总被引:1,自引:0,他引:1       下载免费PDF全文
采用多元统计方法,从福建省14个市、县的52个乡、镇、市区调查结果表明,胃癌死亡率以40/10万为界,分为胃癌高发区和中低发区,两者间地理分布差异明显。胃癌高发区位于中部沿海平原,地质背景以第四纪海积层为主,四周为中生代酸性-中酸性火山岩及花岗岩类侵入体。区内断裂构造发育。环境地球化学以缺乏铁、钴、镍、钒与异常富集的汞、金、钡为特征,其中,铁、钴的协同抑制胃癌高发区有明显的作用,金、汞协同诱发胃癌的作用值得进一步研究。  相似文献   
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