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1.
Benzo[a]pyrene (BaP) is a polycyclic aromatic hydrocarbon (PAH) in particulate matter that has a diameter of ≤2.5 μm (PM2.5). Studies have demonstrated that BaP exposure causes oocyte meiotic arrest in mice. However, whether BaP exposure also affects oocyte maturation in offspring remains unclear. To test this, female mice were administered BaP before pregnancy to generate BaP-exposed offspring. Our findings showed that BaP exposure reduced the in vitro maturation and increased the abnormalities of meiotic apparatus in offspring oocytes. In addition, BaP exposure reduced the mitochondrial content and intracellular ATP generation, induced early apoptosis, increased reactive oxidative species accumulation and the genomic DNA 5-methylcytosine (5mc) level in offspring oocytes. Along with the abovementioned defective parameters, maternal BaP exposure further compromised the embryo developmental competence of offspring oocytes. In summary, our study demonstrated that maternal BaP exposure compromised offspring oocyte maturation and quality.  相似文献   
2.
Environmental chemical exposure could be an important etiologic factor for geographic differences in breast cancer incidence. In this study, we examined emissions of polycyclic aromatic hydrocarbons (PAHs) and PM2.5 in relation to breast cancer incidence in metro Atlanta and rural Georgia by analyzing data from the Surveillance, Epidemiology, and End Results Program and the Environmental Protection Agency. The results showed that metro Atlanta had a significantly higher age-adjusted annual incidence rate of female breast cancer than rural Georgia (132.6 vs. 113.7 per 100,000) for 1992–2011. Emissions of both PAHs [adjusted β = 0.568 (95 % CI: 0.209, 0.927); p = 0.004] and PM2.5 [adjusted β = 2.964 (95 % CI: 0.468, 5.459); p = 0.023] were significantly associated with breast cancer incidence in metro Atlanta area. This study suggests that ambient air pollution, especially PAHs and PM2.5, could have a significant impact on the increased incidence of female breast cancer in urban areas.  相似文献   
3.
In this study, we estimated the disease burdens attributable to environmental tobacco smoke (ETS) exposure in Korean adults in 2010 and analyzed the trend of that from 2005 to 2010. We obtained information on the study population from the 2010 Cause of Death Statistic and estimated the ETS-attributable fraction using data from the Korean Community Health Survey and the Korean National Health and Nutrition Examination Survey. The numbers of ETS-attributable deaths in female and male non-smokers were estimated to be 4.1 and 69.6?% of the numbers of deaths attributable to current smoke, respectively. The deaths attributable to ETS were larger in female than in male non-smokers (710 vs. 420). The ETS-attributable deaths increased slightly in 2005–2008 but decreased in 2009–2010. The number of potential years of life lost from ETS was 9077.24?years in 2010. If there were no exposure to ETS in adult non-smokers, we would expect to see 1130 fewer deaths (9.9?% of the deaths from current smoke). The results suggest that ETS poses considerable disease burdens for non-smokers, especially women, in Korea.  相似文献   
4.
《Vaccine》2016,34(50):6316-6322
ObjectiveAir pollution, weather condition and influenza are known risk factors of acute coronary syndrome (ACS) among elderly people. The influenza vaccine (IV) has been shown to reduce major cardiovascular events. The purpose of this study was to compare resistance to air pollution and weather factors causing ACS between vaccinated and less-vaccinated elderly people.MethodsA case–crossover design was applied to 1835 elderly ACS patients who were obtained from the 1-million sample of Taiwan National Health Insurance Research Data with inclusion criteria: (1) the first diagnosis of ACS was in cold season and at age 68 or more, (2) had received the free IV program at least once during the period 3 years before the ACS. They were stratified into two groups: 707 had received flu vaccinations for all the 3 years and the remaining 1128 had not. The measurements of air pollutants, temperature, and humidity corresponding to each of the 3 days prior to the ACS diagnosis date were retrieved from the data banks of the Taiwan Environmental Protection Administration and Central Weather Bureau.FindingsIncreases in air pollution concentrations of CO, NO2, PM10 or PM2.5 and decreases in temperature significantly influenced the risk of ACS for the non-continuously vaccinated elderly population; however, less significant effects were observed for the continuously vaccinated population.ConclusionConsecutive influenza vaccination may potentially offer resistance against the detrimental effects of air pollution and changes in temperature in frail elderly adults with ACS. Future studies are needed to directly assess the interaction effect between the vaccination and environmental factors on ACS.  相似文献   
5.
蛭弧菌与微生物污染的相互关系探讨   总被引:1,自引:0,他引:1  
本文在实验室条件下动态观察了蛭弧菌含量与微生物污染的相互关系。结果表明:蛭弧菌含量的增加滞后于水体污染,而污染过后蛭弧菌则可在较长时间内维持较高水平,这一特性在水污染指示中的可能作用值得进一步探讨。  相似文献   
6.
白洋淀污染一直是国家和河北省所关注的问题,对白洋淀上游蓄污工程沿岸小环境调查表明;饮用深层地下水受到城市工业废水的污染,主要污染物为有机物。污染区儿童贫血率、白细胞计数、舒张压高于非污染区,白细胞吞噬率低于非污染区,居民恶性肿瘤标化死亡比高于非污染区,肝癌标化死亡比明显上升。  相似文献   
7.
Respiratory infections (RI) are one of the major complaints in children and adolescents, and represent a demanding challenge for the pediatrician. It has been estimated that at least 6% of Italian children younger than 6 yr of age present recurrent respiratory infections (RRI). Children with RRI are not affected by severe alterations of the immune system. RRI represent essentially the consequence of an increased exposure to infectious agents during the first years of life, when immune functions are still largely immature. Several social and environmental factors, such as day-care attendance, family size, air pollution, parental smoking, and home dampness, represent important risk factors for airway diseases and may contribute in various degrees to determine the incidence of RRI. The main problem for the pediatrician is to discriminate normal children with high RI frequency related to an augmented exposure to environmental risk factors from children affected by other underlying pathological conditions (immunological or not), predisposing to infectious diseases. When RRI diagnosis has been formulated, removal of environmental risk factors (i.e. precocious day-care attendance, smoking in the household) must first be suggested.  相似文献   
8.
对液化气燃烧后室内空气污染进行了流行病学调查,结果显示,液化气燃烧可造成SO_2、NO_2、空气总悬浮颗粒物和总烃类的室内空气污染。小鼠接触三个月出现T淋巴细胞计数降低、睡眠时间延长、骨髓嗜多染红细胞微核率增加、肺组织匀浆Ames试验阳性率增高、雄性小鼠精子畸形率增加,并有明显的剂量-反应关系。对接触5年以上的人群调查发现,呼吸道、鼻和眼的自觉症状明显增加,咽炎、鼻炎、结膜炎患病率增高。人群尿液浓缩物Ames试验和外周血红细胞微核率检出阳性结果,可能与液化气燃烧废气中含有致突变污染物有关。  相似文献   
9.
烹调油烟对机体健康的危害   总被引:17,自引:0,他引:17  
王献仁 《卫生研究》1994,23(5):274-277
烹调油烟气含有200多种有害气体。实验研究和流行病学调查表明:油烟气可损伤肺部功能,引起机体免疫功能下降,并具有致突变性和致癌性,是肿瘤发生的可疑因素。  相似文献   
10.
佛山市城区室内装修污染特征初探   总被引:8,自引:0,他引:8  
目的 为了解佛山市室内装修空气污染状况,通过对佛山市室内装修污染物进行调查,掌握室内装修污染的一些基本特征并提出控制措施。方法 根据卫生部《室内空气质量卫生规范》以及《室内空气污染物的检验方法》方案,调查采用了问卷调查和现场检测的方法。结果 佛山市室内装修空气污染物主要为甲醛,苯,总挥发性有机物(TVOC),超标率分别为86%,36%,23%。结论 目前佛山市城区室内装修污染物的特征为:有机污染较无机污染严重,室内甲醛污染严重,苯次之而氢污染相对较轻,室内空气苯污染车辆、居室高于办公室,甲醛污染居室,办公室高于车辆。  相似文献   
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