燃煤型氟中毒大鼠诱导型一氧化氮合酶蛋白表达、血清睾酮与生精细胞凋亡的相关性研究

目的:研究燃煤型氟中毒大鼠睾丸组织诱导型一氧化氮合酶(iNOS)蛋白表达、血清睾酮(T)与生精细胞凋亡的相互关系,探索燃煤型氟中毒对睾丸生殖功能损伤的机制。方法:将40只雄性SD大鼠随机分为4组:对照组、低氟组、中氟组、高氟组。各染毒组喂饲含不同比例的燃煤型氟中毒病区煤烘玉米的饲料,建立雄性大鼠燃煤型氟中毒模型。分别于染毒4和6个月后以股动脉放血法处死大鼠,各时间点每组处死大鼠5只。采用RIA法测定大鼠血清T水平;检测血清中超氧化物歧化酶(SOD)活力、丙二醛(MDA)含量、iNOS活性;原位缺口末端标记(TUNEL)法检测大鼠睾丸生精细胞凋亡情况并计算凋亡指数(AI);免疫组织化学染色SP法观察iNOS蛋白表达的变化。结果:成功建立雄性大鼠氟中毒模型。大鼠血清T水平在4和6个月时低氟组[(28.37±0.19)nmol/L、(14.68±0.36)nmol/L]、中氟组[(25.85±0.23)nmol/L、(9.08±0.31)nmol/L]、高氟组[(23.63±0.29)nmol/L、(4.89±0.54)nmol/L]较对照组[(29.77±0.43)nmol/L、(29.97±0.36)nmol/L]均降低(P0.05或P0.01),且各染氟组间差异有统计学意义(P0.05或P0.01)。睾丸生精细胞AI在4和6个月时低氟组(8.83±1.64、10.40±2.70)、中氟组(17.24±3.96、22.20±3.96)、高氟组(44.21±7.85、49.60±4.77)较对照组(0.46±0.11、0.54±0.11)升高(P均0.01),且各染氟组间差异有统计学意义(P0.05或P0.01)。睾丸组织iNOS蛋白表达的OD值在4和6个月时低氟组(0.073 3±0.008 5、0.108 4±0.012 6)、中氟组(0.142 5±0.027 2、0.207 7±0.020 4)、高氟组(0.527 5±0.079 1、0.717 3±0.065 6)较对照组(0.001 3±0.000 2、0.001 6±0.000 1)增加(P0.05或0.01),且各染氟组间差异有统计学意义(P0.05或P0.01)。iNOS蛋白表达量与生精细胞AI呈正相关(r=0.962,P0.01);血清T水平与生精细胞AI呈负相关(r=-0.744,P0.01)。结论:血清T水平改变和睾丸组织iNOS蛋白表达调控改变可能参与燃煤型氟中毒对睾丸生殖功能损害的过程。     

Health Implications of PAH Release from Coated Cast Iron Drinking Water Distribution Systems in the Netherlands

Background: Coal tar and bitumen have been historically used to coat the insides of cast iron drinking water mains. Polycyclic aromatic hydrocarbons (PAHs) may leach from these coatings into the drinking water and form a potential health risk for humans.Objective: We estimated the potential human cancer risk from PAHs in coated cast iron water mains.Method: In a Dutch nationwide study, we collected drinking water samples at 120 locations over a period of 17 days under various operational conditions, such as undisturbed operation, during flushing of pipes, and after a mains repair, and analyzed these samples for PAHs. We then estimated the health risk associated with an exposure scenario over a lifetime.Results: During flushing, PAH levels frequently exceeded drinking water quality standards; after flushing, these levels dropped rapidly. After the repair of cast iron water mains, PAH levels exceeded the drinking water standards for up to 40 days in some locations.Conclusions: The estimated margin of exposure for PAH exposure through drinking water was > 10,000 for all 120 measurement locations, which suggests that PAH exposure through drinking water is of low concern for consumer health. However, factors that differ among water systems, such as the use of chlorination for disinfection, may influence PAH levels in other locations.     

《黄帝内经》影响下的《金匮要略》“气化观”探析

探究《黄帝内经》影响下的《金匮要略》"气化观"。运用历史考察、文本分析等文献研究方法，对先秦两汉文化背景下，《黄帝内经》等著作中"气化"这一概念所体现的哲学、医学内涵进行分析，从道、法、术3个层面揭示在其影响下的《金匮要略》"气化观"的形成原因。秦汉哲学认为"气化"是宇宙万物生成的原因和运动的法则，古代医学认为人体气化遵循天地四时阴阳、五行的运行方式，这些都影响了《金匮要略》健康观、诊疗观及其遣方用药原则的形成。《黄帝内经》对《金匮要略》气化理论的构建产生重要影响。     

Estimation of Coal’s Sorption Parameters Using Artificial Neural Networks

This article presents research results into the application of an artificial neural network (ANN) to determine coal’s sorption parameters, such as the maximal sorption capacity and effective diffusion coefficient. Determining these parameters is currently time-consuming, and requires specialized and expensive equipment. The work was conducted with the use of feed-forward back-propagation networks (FNNs); it was aimed at estimating the values of the aforementioned parameters from information obtained through technical and densitometric analyses, as well as knowledge of the petrographic composition of the examined coal samples. Analyses showed significant compatibility between the values of the analyzed sorption parameters obtained with regressive neural models and the values of parameters determined with the gravimetric method using a sorption analyzer (prediction error for the best match was 6.1% and 0.2% for the effective diffusion coefficient and maximal sorption capacity, respectively). The established determination coefficients (0.982, 0.999) and the values of standard deviation ratios (below 0.1 in each case) confirmed very high prediction capacities of the adopted neural models. The research showed the great potential of the proposed method to describe the sorption properties of coal as a material that is a natural sorbent for methane and carbon dioxide.     

Study of Mechanical Properties and Durability of Alkali-Activated Coal Gangue-Slag Concrete

Herein, a new geopolymer is recognized as a potential alternative cementing material of ordinary Portland cement (OPC), which is used for reducing carbon emissions and efficiently recycling the waste. Therefore this paper mainly studied the alkali-activated coal gangue-slag concrete (ACSC) was prepared by using the coal gangue-slag and Na₂SiO₃ and NaOH complex activator. The ratio of coal gangue (calcined and uncalcined) coarse aggregate replacing the gravel was 0%, 30%, 50%, 70%, and 100%. The water and salt freeze-thaw resistance, compressive strength, chloride permeation, microstructure, performance mechanism, inner freeze-thaw damage distribution, and mechanics models of ACSC were investigated. Results show that ACSC displayed excellent early age compressive strength, and the compact degree and uniformity of structure were better compared with the ordinary Portland cement (OPC) when the coal gangue replacement rate was less than 50%. The ACSC demonstrated the best chloride penetration resistance under 30% uncalcined coal gangue content, which was less than 27.75% lower than that of using OPC. At the same number cycles, especially in the salt freezing, the calcined coal gangue had lowered advantages of improving resistance freeze-thaw damage resistance. Water and salt accumulative freeze-thaw damage mechanics models of ACSC were established by using the relative dynamic elasticity modulus. The exponential function model was superior to the power function model with better precision and relativity, and the models accurately reflected the freeze-thaw damage effect.     

A Study on the Utilization of Coal Fly Ash Derived Grog in Clay Ceramics

Grog is an additive material that plays important roles in ceramic making. It improves the fabrication process of green bodies as well as the physical properties of fired bodies. Few low-cost materials and wastes have found their application as grog in recent years, thus encouraging the replacement of commercial grogs with cost-saving materials. Coal fly ash, a combustion waste produced by coal-fired power plant, has the potential to be converted into grog owing to its small particle sizes and high content of silica and alumina. In this study, grog was derived from coal fly ash and mixed with kaolin clay to produce ceramics. Effects of the grog addition on the resultant ceramics were investigated. It was found that, to a certain extent, the grog addition reduced the firing shrinkage and increased the total porosity of the ceramics. The dimensional stability of the ceramics at a firing temperature of 1200 °C was also not noticeably affected by the grog. However, the grog addition in general had negative effects on the biaxial flexural strength and refractoriness of the ceramics.     

煤矿农民工预防艾滋病不同干预措施成本效果比较

目的探讨煤矿农民工预防艾滋病不同干预措施的效果及成本效果。方法于2009年7—12月选取开滦矿业集团某煤矿农民工459人,在基线调查基础上分成3组,分别采用发放宣传品、专业讲座、同伴教育3种干预措施;收集干预前后艾滋病相关危险性行为及安全套使用率,使用艾滋病病毒(HIV)传播模型计算每种干预措施所能避免的HIV感染例数,同时计算成本效果比。结果以近5个月内有偿性服务的安全套使用率为指标评价实施干预后危险性行为的变化,发放宣传品组由50.7%(35/69)上升到了55.2%(32/58),差异无统计学意义;而专业讲座组由51.0%(50/98)上升到了78.0%(32/41),同伴教育组由44.6%(25/56)上升到了66.7%(30/45),差异均有统计学意义(χ2=23.342、15.920,P<0.05);从总的知晓率来看,干预后专业讲座组61.3%(92/150),高于发放宣传品组的45.8%(66/144)和同伴教育组的50.3%(83/165),而后两者无明显差异;3种干预措施每避免1例HIV感染需要的平均成本分别为48 214.29、41 195.65和55 138.89元,专业讲座的成本效果比最高。结论以3种干预措施的效果和成本效果比为评价指标,专业讲座最好、同伴教育次之、发放宣传品最差。     

Nrf2和Keapl mRNA表达在燃煤型砷中毒肝损伤中作用

目的 探讨Nrf2和Keapl mRNA表达在燃煤型砷中毒肝损伤中的作用.方法 选择贵州省燃煤污染型砷中毒病区133例砷暴露者为砷暴露组(包括病区非病人组、无明显肝病组、轻度和中重度肝病组),以非砷污染村34名健康居民为对照组;实时荧光定量PCR检测外周血Nrf2和Keapl mRNA表达,化学法检测超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)、硫氧还蛋白还原酶(TrxR)活力和丙二醛(MDA)含量.结果 对照组、病区非病人组、无明显肝病组、轻度和中重度肝病组Nrf2 mRNA表达量分别为0.650 5、0.6904、0.877 8、1.283 4和1.393 5,Keapl mRNA表达量分别为1.569 1、1.451 0、1.395 4、1.0489和0.882 0;与对照组、病区非病人组和无明显肝病组比较,轻度和中重度肝病组Nrf2 mRNA表达上调,Keapl mRNA表达下调,SOD活力降低(P＜0.05);中重度肝病组GSH-Px和TrxR活力降低,MDA含量升高(P＜0.05).Nrf2 mRNA表达与酶活力呈负相关、与MDA含量呈正相关,Keapl mRNA表达与酶活力呈正相关(P＜0.05).结论 燃煤砷可能通过调控Nrf2和Keapl mRNA表达量,调节机体氧化应激水平,参与砷中毒肝损伤的发生发展.     

井下煤矿工人和地面煤矿工人心理健康水平调查比较

目的:调查比较井下作业煤矿工人和地面作业煤矿工人心理健康状况水平。方法:用症状自评量表(SCL-90)对283名井下煤矿工人和219名地面煤矿工人的心理健康水平进行问卷调查。结果:煤矿工人SCL-90总分、总阳性项目数、阳性症状均分、躯体化、人际关系、抑郁等各因子分均高于国内常模,并有极显著性差异。井下矿工SCL-90总分、阳性项目数和躯体化、人际关系、焦虑、恐怖因子均分均高于地面矿工,并有显著性差异。结论:煤矿工人的总体心理健康水平低于国内常模,井下煤矿工人的心理问题较地面作业煤矿工人更为明显,应加强心理健康综合性干预。