某铀矿山及其周边地区地下水重金属健康风险评估

分别对某铀矿山及周边地区于丰水期、平水期和枯水期各采集了20个钻孔地下水样品进行测试,分析了5种重金属铅、锰、铬(六价)、镉、砷的含量,并采用风险评估模型对铀矿山及其周边地区进行健康风险的初步评估。结果表明,研究区地下水总健康风险值范围为8.74×10-7~1.06×10-4 a-1,95%的地下水样品总健康风险值低于ICRP和USEPA推荐的可接受的健康风险值,地下水中的重金属含量不会对周边居民产生明显危害。     

深海鱼体中砷含量的测定与健康风险评价

[目的]通过测定10种常见深海鱼体中砷的含量,并对海南省沿海居民经由饮食途径摄入砷的健康风险进行评估,为合理的饮食提供基础数据和参考.[方法]利用混合液(硝酸+过氧化氢)消化样品,以盐酸作载流,采用氢化物-原子荧光法进行测定;采用目标危险系数(THQ)的方法对海南省沿海居民食用深海鱼的健康风险进行了评价.[结果]10种深海鱼的砷水平在0.018 5～0.091 2mg/,kg范围内,均低于<食品中污染物限量>(GB2762-2005)对无公害海产品中砷含量的限量标准(≤0.1 mg/kg),未出现超标现象.对成年人食用深海鱼的健康风险评估发现:海南省沿海居民长期食用带鱼、白鲳鱼、金线鱼、马鲛鱼、黄尾鱼、鲇鱼的目标危险系数大于1,存在健康风险;长期食用黄花鱼、石斑鱼、海肝鱼的目标危险系数接近1,有潜在的健康风险.[结论]在日常饮食中,合理搭配不同种类的鱼种以减少摄入重金属的健康风险,避免单一大量食用风险系数大于1的鱼种.     

汞矿区土壤和农产品重金属污染状况及风险评估

为了解汞矿选冶采矿活动对当地生态环境的影响,以贵州某汞矿区尾矿堆场为研究对象,利用随机布点法采集土壤样品及农产品各60份,利用内梅罗综合指数法、潜在生态风险评价法对土壤重金属污染程度进行评价,利用健康风险评估模型对农产品中重金属的健康危害进行评估。结果表明,研究区土壤复合污染程度为重污染,Hg贡献最大,Cd次之,且A区较B区土壤污染严重。蔬菜、稻米、玉米中Hg的超标率分别为82.8%、46.7%、20%,蔬菜中Cd的超标率为51.7%,其他元素均低于限量标准。食用当地稻米及蔬菜对人群产生的健康危害指数HI1,可能存在潜在健康风险,玉米对人群产生的健康危害指数较小,其潜在健康风险可忽略不计。土壤重金属含量与农产品中重金属含量无明显相关性。     

典型地膜残留地区土壤重金属残留测定及其健康风险评价

以典型地膜残留区——河南省开封县郭庄西瓜种植区的土壤和农产品中重金属残留为研究对象,开展了重金属分布和污染状况分析,并对食用西瓜引起的健康风险进行了评价.结果表明:土壤中Cd的含量是国家标准值的3.25倍,处于中度污染级别,且还存在一定程度的Pb污染;由膳食途径所致的健康风险评价中,化学致癌物质Cr的年健康风险值较大,为4.39×10~(-3)a~(-1),高于国际辐射防护委员会(ICRP)推荐的最大可接受风险水平(5.0×10~(-5)a~(-1)).化学致癌重金属的个人年风险占总年风险的87.7%,且与非致癌重金属的个人年风险值相差4个数量级,这表明开封县西瓜中的重金属对人体存在一定的健康风险.     

井下紧急避险设施内人体舒适度预测模型

长时间处在不舒适的环境中,将对人体健康产生严重影响。井下紧急避险设施中,影响避险人员舒适性感觉的因素众多,本文选取氧气含量、二氧化碳含量、温度和相对湿度四个关键因素为研究对象,采用分级评分法,进行了系列真人模拟生存试验,获得了单一环境变量和多个环境变量条件下总计169组有效人体舒适度投票数据.经统计分析,分别得出了密闭舱室内单一环境变量与人体舒适度感觉之间的函数关系以及避险人员舒适度预测模型,分析了氧气含量、二氧化碳含量、温度和相对湿度的允许范围及调控原则.      

萍水河地表水重金属污染特征及健康风险评价

以萍水河何雁桥至向阳湖段为研究对象,在21个采样点采集地表水样品,首先分析水体中10种重金属的空间污染特征,然后运用多元统计法对重金属间的相关性进行分析,最后采用USEPA推荐的健康风险评价模型评价重金属经饮水途径对成人和儿童产生的健康风险。结果表明,V、Fe、Mn的最大值均超过《地表水环境质量标准》(GB 3838—2002)Ⅲ类水质标准,最大超标2.3倍,重金属浓度均值大小依次为：Fe>Mn>V>Zn>Mo>As>Cu>Cd>Pb>Cr;从空间分布特征看,重金属多集中在研究区上游和下游,受人类工农业活动影响明显。Cu与Fe、Cu与Cr、Fe与Mn、As与V间呈现显著相关,相关系数分别为0.704、0.677、0.671和0.440,具有相同的来源或转换过程;Mo与Cu、Mo与Cr呈负显著相关,相关系数分别为-0.51、-0.44,表明来源不同或者两者间相互抑制。成人与儿童的健康总风险均大于最大可接受风险水平1.0×10-6,污染物致癌风险值比非致癌风险高3~4个数量级,总健康风险主要由Cr、As、Cd产生,儿童健康风险比成人健康风险高。模型参数的合理取值和本土化是精确量化地表水中重金属对人体健康影响的关键要素,特别对儿童进行健康风险评价应分年龄段计算。     

金属矿区土壤重金属汞砷含量特征及潜在风险评价

通过分析某一金属矿区的土壤重金属砷元素和汞元素含量,分析重金属含量特征和潜在风险,当砷元素和汞元素的平均值低于115时,风险水平较低;当砷元素和汞元素的平均值在115到130时.风险水平处于中度;当砷元素和汞元素的平均值高于130时,风险水平很高。随着深度的增加,汞元素和砷元素的含量也在不断增加,但是变化幅度不同。     

多种含砷废渣资源化工艺方案研究

在冶金和化工过程中有大量的含砷废渣产生,大量的含砷废渣对生态环境造成破坏,同时也危及人体安全.而很多含砷废渣种类多、产生量小是砷渣处置的难题.文章从工程设计的角度,论述多种含砷废渣资源化方案,作为多种含砷废渣资源化方案的参考.     

基于循环经济的南四湖流域经济发展模式及对策研究

从南四湖流域应该大力发展循环经济模式入手,阐述了循环经济的含义,对南四湖流域在发展循环经济中农业、工业企业、废物利用等方面存在的问题进行分析,结合循环经济发展的农户、企业、区域以及社会4种模式,针对南四湖流域发展循环经济提出相应的对策和建议:一是建立发展南四湖流域大农业循环经济的政府引导机制;二是建立南四湖流域循环经济的工业企业激励制度;三是调整南四湖流域产业结构,优化能源消费结构.     

程潮矿区周边土壤重金属污染风险评价和健康风险评估

采用单因子指数法、内梅罗指数法、潜在生态风险指数法和地累积指数法对程潮铁矿尾矿库及周边农田土壤重金属（镉、砷、铅、铬、铜、镍和锌）的生态风险及人体健康风险进行综合评价。单因子风险评价结果显示,尾矿库土壤As和Cu的污染问题突出,超标率分别为33.3%和41.7%,其它重金属在少数点位超标;农田土壤仅重金属Cd超标。内梅罗综合污染指数结果表明,16.7%的尾矿位点处于中度污染水平,25%的尾矿位点处于重度污染水平;农田土壤整体上较清洁。尾矿土壤中41.7%的Cu处于中等潜在生态风险水平,41.7%的土壤Cu属于中度~强污染地质累积风险,少数位点由于Cd和As含量较高,达到较高等级的潜在生态风险和地质累积风险。农田土壤重金属污染物主要为Cd,局部地区达到中等潜在生态风险和地质累积风险。人体健康风险评价结果表明,As和Cr的非致癌风险和致癌风险均较为突出,整体而言,尾矿区有33.3%的位点存在致癌风险,所有土壤的非致癌风险等级低,对人体健康的风险较低。由于少数位点重金属污染问题突出,仍需加强该尾矿及其周边农田土壤重金属的污染防治和风险管控。     

Regional differences in suicide in Hungary in the light of registered cases of depression

Author made a revision on the theory published by Rihmer and alii in the year 1989. According to this theory the marked regional differences of suicide in Hungary are caused by the different discovery of the "endogen depression" (rate of diagnosed depression). So the lower is the diagnosis of depression the higher is the suicide rate in a given territory. They have seen a negative correlation between the number of working physicians and the suicide rates. Author made a reexamination on a correct database between 1985-1994. He has also made a study using the DSM-III-R diagnostic criteria in four counties of Hungary. His results deny the theory above mentioned. The rank-correlation of the number of GP and the suicide rates in Hungary in years 1985-1994 did not show correlation. So the underdiagnosis of the depressive disorders and the different number of GP are not the cause of the regional differences of suicide in Hungary.     

Role of clozapine in the occurrence of chromosomal abnormalities in human bone-marrow cells in vivo and in cultured lymphocytes in vitro

Bone-marrow chromosomes were examined from 38 mentally and physically retarded and two psychiatric patients who were being treated with a variety of neuropharmacologic drugs. Twenty of these patients used clozapine (Leponex). The clastogenic effects of clozapine in vitro were studied in the lymphocyte cultures of three patients--one free of hematologic disease and two who 6 months earlier had had agranulocytosis attributed to the use of clozapine. The mean frequency of cytogenetic abnormalities in the bone-marrow cells of patients who used clozapine was significantly increased (P less than 0.05). The two patients who had had agranulocytosis had a greater frequency of cytogenetic abnormalities in their cultured lymphocytes in vivo and in vitro than the patient free of hematologic disease. A clone with a 13/14 chromosome translocation was detected in one of the patients. As all patients received a number of drugs during the in vivo and in vitro studies no definite conclusions could be drawn regarding the role played by clozapine in the occurrence of chromosomal abnormalities.     

Inhibitory effect of suramin in rat models of angiogenesis in vitro and in vivo

The aim of the present study was to test the ability of the chemotherapeutic agent suramin to inhibit angiogenesis in experimental models in vitro and in vivo. In the culture of rat aortic rings on fibronectin, suramin dose-dependently inhibited vascular cell growth, achieving the maximal effect (mean - 88% versus controls, P < 0.05) at 400 microg/ml. Image analysis showed that suramin could inhibit microvessel sprouting in fibrin from rat aortic rings as evaluated by the ratio between the cellular area and the mean gray value of the sample (sprouting index); suramin at 50 microg/ml significantly reduced the sprouting index from the control value of 0.35+/-0.04 to 0.14+/-0.02 mm2/gray level (P < 0.05). Likewise, the area occupied by cells was 19.2+/-1.8 mm2 as compared with 41.8+/-4.2 mm2 in controls (P < 0.05). In the rat model of neovascularization induced in the cornea by chemical injury, suramin at 1.6 mg/eye per day reduced the length of blood vessels (0.7+/-0.1 mm as compared with 1.5+/-0.1 mm in controls, P < 0.05). In the same model the ratio between the area of blood vessels and the total area of the cornea (area fraction score) was decreased by suramin from 0.19+/-0.02 in controls to 0.03+/-0.003 (P < 0.05). Suramin given i.p. at 30 mg/ kg per day markedly inhibited the neovascularization induced in the rat mesentery by compound 48/80 or conditioned medium from cells secreting the angiogenic protein fibroblast growth factor-3 (FGF-3). The area fraction score in control rats treated with compound 48/80 was 0.31+/-0.03, and this was reduced to 0.07+/-0.01 by suramin (P < 0.05). After i.p. administration of FGF-3 the area fraction score was reduced by suramin from 0.29+/-0.03 to 0.05+/-0.01 (P < 0.05). These results provide evidence that suramin exerts inhibitory effects on angiogenesis in both in vitro and in vivo models.     

Difference in changes of plasma volume in two types of Goldblatt hypertension in rabbits

High plasma renin concentration (PRC) and hematocrit (Ht) were observed in hypertensive rabbits with one renal artery clipped and an intact opposite kidney (Group A), while rather low PRC and Ht in hypertensive ones with one renal artery clipped and the opposite kidney removed (Group B). Plasma volume (PV), blood volume (BV), and packed cell volume (PCV) were estimated in these two types of hypertensive rabbits, and also in sham-operated rabbits (Group C). In Group A, 4 weeks after clipping of a renal artery, PV was decreased and significant inverse correlations were observed between PV and the elevation of blood pressure and between PV and PRC. A significant correlation between PRC and the elevation of blood pressure was also found 4 and 12 weeks after the clipping. PCV was increased until 12 weeks after clipping. In Group B, PV was increased 1 and 4 weeks after clipping, then returned to the initial level. Ht was decreased 1 and 12 weeks, and PCV was decreased 12 weeks after clipping. These results would indicate that a high Ht seen in Group A was partly due to the decreased PV and partly due to the increased PCV, while, in Group B, a low Ht in early stage might be mainly due to the increased PV, but in the late stage, a decreased PCV appeared to play a role to lower Ht. PRC seems to be affected differently by PV in these two types of hypertension.     

CS1000在天铁烧结生产过程控制中的应用

结合天津铁厂烧结分厂二烧车间烧结过程控制的具体情况,介绍了分散型控制系统在烧结生产上的应用以及数据网上发布的一种方法。     

Efficacy of lomefloxacin in treatment of nonspecific inflammatory diseases and in prophylaxis of postoperative complications in urology

Clinical and bacteriological efficacies of lomefloxacin and ofloxacin were comparatively estimated in the treatment of 104 urologic patients with nonspecific inflammatory diseases and in 36 urologic patients for prophylaxis of inflammatory complications after surgical interventions. The majority of the urinary tract pathogens i.e. Enterobacteriaceae spp. and gramnegative nonfermenting bacteria were highly susceptible to both the fluoroquinolones. The clinical and bacteriological efficacies of lomefloxacin amounted to 94.4 and 80.7 per cent and those of ofloxacin to 92 and 79.2 per cent respectively. The prophylactic use of lomefloxacin and ofloxacin was efficient in 94.7 and 94.1 per cent of the cases respectively. The antibacterial prophylaxis in urologic patients should be applied not only at the period of surgical interventions but also during the early postoperative period.     

Epidemiology of trichinellosis in lynx in Finland

To examine the possibility of cytokine gene therapy in relation to pancreatic cancer, we evaluated the antitumor effect of human pancreatic carcinoma cells (AsPC-1) which were retrovirally-transduced with several kinds of cytokine genes. These cells were inoculated into BALB/c nude mice and their tumor volumes were assessed. The in vitro growth rate of the transduced cells was not different from that of a parental cell line. Among the transduced cells, human interleukin (IL)-6-transduced AsPC-1 and mouse granulocyte macrophage colony-stimulating factor-transduced AsPC-1 cells showed a significant retardation of tumor growth compared with a parental cell line. In the cases of AsPC-1 cells transduced with the human IL-2 or mouse IL-4 gene, small tumors were generated but thereafter they regressed completely. Histological examinations showed monocytic cell infiltration around the tumors of IL-2- or IL-4-producing cells. These data suggest that secretion of IL-2 or IL-4 from tumor cells can induce an antitumor effect even in the defective condition of mature T cells.