新疆巴音布鲁克高寒草地土壤几种公害物生态安全的研究

在随机采样和精确检测的基础上,参照国家土壤环境质量标准,对新疆巴音布鲁克高寒草地亚高山草原土中,六六六、敌敌畏、铅和砷的生态安全予以了评估,结果表明：土壤中六六六、敌敌畏、铅和砷的生态安全率均达100％。亚高山草原土居于生态安全状态。     

巴音布鲁克高寒草地饲草几种公害物生态与经济安全的研究

在随机采样和精确检测的基础上,参照国家饲料卫生标准,对巴音布鲁克高寒草地饲草六六六、敌敌畏、铅和砷的生态与经济安全予以了评估,结果表明：饲草中六六六、敌敌畏和砷的生态、经济安全率均达100％,铅的生态、经济安全率均达93．75％。     

巴音布鲁克肉羊几种公害物综合安全的研究

在随机采样和精确检测的基础上,参照国家和部颁标准,对巴音布鲁克肉羊中,六六六、敌敌畏、铅和砷的综合安全予以了评估．结果表明：肉羊中六六六、敌敌畏和砷的生态、经济和社会安全率均达100％,铅的生态、经济和社会安全率均达87．5％。     

甘肃省土壤砷含量调查

为了解甘肃省土壤中砷的含量,我们于1987年至1992年对甘肃省不同类型土壤进行了调查分析,现将结果报告如下。 1 土壤类型及分布 土壤类型具有明显的复杂性和区域性。河西走廓为灌淤土及潮土,陇南山区为麻土,陇东地区为黄绵土,宁夏地区为垆土,中部地区为灰     

敌敌畏杀灭臭虫现场效果观察

杀灭臭虫常用的方法有烫煮、水泡、搜捕、嵌封,以及六六六、二二三药杀等,但缺点是费力大,不易全面处理和根除,而且有些地区发现臭虫对六六六、二二三已产生抗药性。为寻求一种简易高效的杀灭方法,我们在1963年10月于某学校中对敌敌畏杀臭虫的效果     

影响优生的食物污染物

农药农药生产厂家直接将废水排入农田,或农药用量过多、次数过频、距农作物收割期太近等,均可使农作物受到农药污染。农药污染物主要有DDT、六六六、艾氏剂、狄氏剂、甲基对硫磷、西维因等。孕妇如果食用了受这些农药污染的农作物,如粮食、蔬菜、水果等,便可导致胎儿唇裂、颚裂、脑积水、先天性肠出血、四肢及泌尿生殖系统畸形等症的发生。重金属元素工业废水违规排放污染了农作物,或者使用不合卫生要求的食品包装材料及食品添加剂,均可使食物中铅、汞、镉等某些重金属元素以及砷元素含量严重超标。这些元素不仅对胚胎具有毒性,可导致胎儿…     

土壤物理性质对土壤氡浓度及地表氡析出率的影响

目的探讨土壤性质对土壤氡浓度及地表氡析出率的影响。方法在北京、贵阳、呼和浩特的31个测量点进行土壤氡浓度及析出率的现场实测。采集土壤样品，在实验室进行土壤镭含量、含水量、孔隙度和粒径分布等物理性质测量。用线性拟合方法分析了实测土壤氡、析出率数据之间的相关性，以及它们与土壤镭含量的关系。结果地表氡析出率与土壤氡浓度和土壤镭含量有正相关关系；土壤含水饱和度过高或过低均会使析出率和土壤氡浓度降低；贵阳地区土壤镭含量较高，但其粉砂黏土壤的特性使土壤氡浓度很难准确采样，导致结果偏低。结论地表氡析出率和土壤氡浓度虽然与土壤镭含量有正相关关系，但在实际环境中易受含水量等多因素影响，而且土壤氡浓度的准确测量受土壤特性限制较大。     

巴音布鲁克高寒草地化学治蝗综合效益评估及其生态安全对策

1955-2000年,在巴音布鲁克高寒草地,采用常规、超低容量和水质微量化学治蝗技术,累计施用六六六和敌敌畏等农药6064.72t,治蝗372193.32ha,投入农药、机械和人工总价值632.44万元,30493.12万kg可饲用鲜草免受损失,形成了草地治蝗的组织工作体制和生态文明道德规范.针对化学治蝗存在的问题,提出了生态安全的对策和建议.     

冬吃菌菇有讲究

草菇草菇中的维生素C含量居菌类之首;具有一定的解毒作用,如铅、砷、苯进入人体,可与其结合,随小便排出;还能减慢人体对碳水化合物的吸收,比较适合糖尿病患者食用。草菇无论是干品还是鲜品,都不宜浸泡时间过长,比较适合做汤或素炒,香菇香菇中富含钾、钙等多种矿物质,且含可以转化为维生素D的麦淄     

原子吸收光谱法测定小儿牛黄散中铅 镉 铜的含量

目的采用原子吸收光谱法（AAS）测定小儿牛黄散中铅、镉、铜的含量,为制订科学合理的限度标准提供实 验依据。方法小儿牛黄散样品用硝酸浸泡过夜后微波消解,用火焰法（F-AAS）测定铜,用石墨炉法（GF-AAS）测定铅和镉。 结果方法的回收率为103.3%、95.7%、108.9%,RSD为3.1%、3.5%、3.0%（n=3）。结论测定样品中铅、镉、铜含量低 于《药用植物及制剂进出口绿色行业标准》;本文方法简便,准确,专属性强,可用于该制剂的质量控制。     

K-shell X-ray fluorescence measurements of arsenic depth-dependent concentration in polyester resin discs using the fundamental parameter method

In the realm of X-ray fluorescence (XRF) applications, inhomogeneous distribution of an element can occur as a function of depth within a sample. An example is the measurement of arsenic in skin; arsenic binds with non-uniformly distributed keratin. In this paper, an XRF signal equation based on the fundamental parameter (FP) method, which explicitly takes into account the depth dependence of the elemental concentration, was developed. The formalism was experimentally verified for two-disc resin stacks with different arsenic concentrations.     

Novel radiochemical separation of arsenic from selenium for 72Se/72As generator

A new radiochemical separation scheme based on extraction chromatography has been proposed for isolation of arsenic from selenium. The distribution coefficients of As and Se on prepared sorbents: (selected aromatic o-diamines supported on polystyrene adsorbents) were determined in order to find the best condition for separation of both the elements. Batch experiments were verified by column studies. This work, together with earlier results from this Laboratory, enabled to elaborate a new separation scheme for selective and quantitative separation of arsenic from selenium. Proposed approach insures high selectivity and radionuclide purity of separated arsenic fraction; it is also characterized by high elution efficiency (>95%) using small volume (2 mL) of 0.9% NaCl with very low breakthrough (<0.01%) of selenium.     

口服二巯丁二酸驱砷治疗5例报告

二巯丁二酸(DMSA)是厂谱金属解毒剂,具有疗效高、毒性小等特点。报告了口服DMSA治疗5例急性砷中毒后期患者,在服药后第1、2d尿砷排出量有不同程度增加,5例皆治愈,且无不良反应。     

细胞凋亡在燃煤型砷中毒肝损伤中的作用

目的 通过观察肝细胞表面分子介导细胞凋亡的Fas、FasL及相关基因Bax、Bcl-2、Bcl-X／L的变化来探索燃煤型砷中毒肝损伤的分子机制。方法 对25例砷中毒肝损伤患者按职业性中毒性肝病诊断标准分为A组4例（无明显肝病患者）、B组11例（轻度砷中毒肝损伤患者）、C组10例（中、重度砷中毒肝损伤患者）。采用免疫组化ABC法进行Fas、FasL、Bax、Bcl-2、Bcl-X／L检测。结果 采用PEMS统计软件进行Radit分析。结果Fas、FasL表达在肝损伤较重的C组比肝损伤较轻的B组显著增强，两组间分级构成上差异均有统计学意义（P〈0．05）；Bax表达在B、C两组间分级构成上差异均有统计学意义（P〈0．05），而Bcl-2和Bcl-X／L表达在B、C两组间分级构成上差异均无统计学意义（P〉0．05）。结论 Fas、FasL的表达程度在肝损伤较重的C组比肝损伤较轻的B组显著增强，其阳性表达多分配在Ⅱ、Ⅲ级。Bax在肝损伤程度不同的B、C组间的表达强度及分布随肝损伤加重而增强。而抗凋亡蛋白bcl-2和bcl-X／L在两组间的表达强度及分布则基本一致。推测砷可能通过上调凋亡基因蛋白Fas／FasL和bcl-2家族中促凋亡蛋白Bax的表达而启动肝细胞的胞内凋亡信号传递过程，导致肝细胞凋亡增加。     

新疆奎屯地区高砷环境中抗砷菌的初步筛选

目的初步筛选新疆奎屯地区高砷环境中（123团4连）自流井水和污水中存在的高抗砷菌,检测其抗砷能力。方法选择高砷自流井水和污水标本,在NaAsO2选择性培养基上,分离和纯化,筛选出抗砷菌,初步进行细胞形态学的鉴定;用不同NaAsO2浓度的LB培养基对菌株抗砷性进行检测,测定其抗砷水平。结果初步筛选出5株抗砷能力较强的抗砷菌。A1、A2、A3均为革兰氏阴性杆菌。B1、B2均为革兰氏阳性球菌;5株菌均可在含有NaAsO2（50．400mg／L）培养基中生长。最高耐受到400mg／L,是新疆奎屯高砷水含量实际最高值的517倍,最低值的1156倍。结论①经初步筛选,确认新疆奎屯地区高砷环境中的自流井水和污水中存在高抗砷菌,首次成功筛选出5株强抗砷菌。②A1菌株的抗砷能力最强,可在400mg／LNaAsO2的LBA培养基上生长。本研究为新疆地区抗砷菌的深入研究提供了基础资料。     

Calculation of MRI-induced heating of an implanted medical lead wire with an electric field transfer function

PURPOSE: To develop and demonstrate a method to calculate the temperature rise that is induced by the radio frequency (RF) field in MRI at the electrode of an implanted medical lead. MATERIALS AND METHODS: The electric field near the electrode is calculated by integrating the product of the tangential electric field and a transfer function along the length of the lead. The transfer function is numerically calculated with the method of moments. Transfer functions were calculated at 64 MHz for different lengths of model implants in the form of bare wires and insulated wires with 1 cm of wire exposed at one or both ends. RESULTS: Heating at the electrode depends on the magnitude and the phase distribution of the transfer function and the incident electric field along the length of the lead. For a uniform electric field, the electrode heating is maximized for a lead length of approximately one-half a wavelength when the lead is terminated open. The heating can be greater for a worst-case phase distribution of the incident field. CONCLUSION: The transfer function is proposed as an efficient method to calculate MRI-induced heating at an electrode of a medical lead. Measured temperature rises of a model implant in a phantom were in good agreement with the rises predicted by the transfer function. The transfer function could be numerically or experimentally determined.     

Study on the distribution of radioactive trace elements in vitamin D-overloaded rats using the multitracer technique.

The uptake and distribution of radioisotopes of beryllium, calcium, scandium, vanadium, chromium, manganese, iron, cobalt, nickel, zinc, gallium, arsenic, strontium and barium in vitamin D (VD)-overloaded rats were investigated and compared with those in control rats, using the multitracer technique. Each element revealed its characteristic distribution among various organs in control and VD-overloaded rats. For some elements, such as cobalt and chromium, the distribution patterns in them were significantly different. These results are discussed in terms of the metabolism of the elements in rats.