Wilson‘s病人和正常人发,粪便中微量元素的中子活化分析

用ＮＡＡ方法测定人发和粪便样品中Ｃｕ、Ｚｎ、Ｃａ、Ｍｎ、Ａｌ和Ｍｇ等六种微量元素，分析比较了病人和正常人样品中微量元素含量的差异。并对病人治疗前后微量元素的变化进行了探讨。     

人发样品中微量元素的XRF分析

通过化学加入法校正吸收效应，采用X射线荧光分析法(XRF)分析人发样品，确定人发中微量元素的含量。以实际人发样品为基础，求得经基体吸收后的相对效率，拟合出相对效率与基体中重要成分Ca含量的关系式，然后用标定的系数进行人发样品中的Ca、Cu、Fe、Zn含量分析。采用此方法分析了一组人发标准物质，并与国标推荐值进行比较，结果表明测定值与推荐值符合情况良好，与国标相比偏差为Ca0．28％，Fe0．99％，Cu2．6％，Zn0；相对测量误差Ca2．2％，Fe1．7％，Cu2．2％，Zn1．1％，其灵敏度≤2．2％。表明采用XRF分析人发中微量元素含量是可行的。     

人发中微量元素的中子活化分析

本文介绍采用长短照射相结合的仪器中子活化分析法,测定了克山病病区、非病区的男性儿童头发中多种微量元素含量。比较了国内常用的及IAEA推荐的清洗方法对头发中微量元素测定的影响。用NBS标准参考物核对了实验中使用的部份标准,结果满意。本工作共分析了48例头发样品中27种元素含量,初步获得了某些元素在三个地区人发中分布的规律。     

内蒙古慢性砷中毒地区少年头发中微量元素含量研究

报道了１９９４－１９９５年在内蒙古呼和浩特市土默特左旗慢性砷中毒病区采集的少年头发样品中砷等十多种微量元素含量的仪器中子活化分析结果，并与北京地区同年龄段少年发样中测量的值进行了比较，发现前者除发砷含量明显高于后者外，两者在其他许多微量元素含量上也存在显著性差异，特别是慢性砷中毒地少年头发中稀土元素和重金属元素Ｆｅ、Ｃｏ、Ｃｒ等的含量均明显高于对照区。所得结果为研究呼和浩特市慢性砷中毒地区人群头发     

能量色散X荧光法测定茶叶中的微量元素

本文介绍了用国产能量色散ｘ射线荧光仪同时测定茶叶中的Ｃａ、Ｍｎ、Ｆｅ、Ｃｕ和Ｚｎ的分析方法。该方法采用将茶叶样品高温灰化，以Ｙ为内标，用ｘ射线荧光分析仪测定微量元素的含量取得了很好的结果。     

质子激发X射线荧光分析法测定头发、肾和肝中的微量元素

本文使用质子激发X射线荧光分析法(PIXE)测定正常人发、肝和肾组织中的微量元素。详细介绍了样品的采集制备、实验测定和定量方法,并且使用标准参考物质小牛肝(NBS)、马肾(IAEA)和比对粉末发样检查校正测量系统的准确性。报道了三种器官组织中近二十种微量元素的含量,初步探讨了人体自身器官组织中微量元素含量分布之间的相互关系。     

正常成年男子肝脏中元素含量的中子活化分析

在我国4个不同膳食类型地区河北、山西、江西和四川,采集21例正常成年男子尸体（意外死亡）的肝脏样品,用中子活化分析方法测定了8种人体必需微量元素的含量。结果表明：肝脏中8种元素的含量由高到低依次为铁、锌、铜、锰、钼、硒、铬、钴,且个体差异大;某些元素的含量地区差异明显,山西样品的Co含量、四川样品的Cr含量和河北样品的Fe含量分别是其它3个地区的1.7~2.0倍、2.5~5.2倍和1.5~2.4倍;与国际辐射防护委员会（ICRP）参考人的最新估算值相比,铬含量明显偏高,铁、铜和钼含量也稍高。作为质量控制,还对3种标准物质中8种元素的含量进行了测定,分析结果与标准值吻合。     

头发中钙及微量元素含量的性别差异研究

用X射线荧光分析法测定了上海和苏州地区4127例居民头发中钙及9种微量元素的含量,发现不管地区与年龄如何,发中Sr、Mn、Ca的含量总是女性高于男性,而Pb含量总是男性高于女性,差异非常显著(p<0.01)。从不同生理条件下发中元素含量的比较中也可以看出,这些元素必然与女性的某些特殊生理功能有联系。     

仪器中子活化分析法测定牛黄中微量元素

我们用仪器中子活化分析法测定了天然牛黄和人工牛黄中20个微量元素的含量。 天然牛黄样品用的是京津地区的京牛黄及进口牛黄两种。人工牛黄样品用的是北京药店现在销售的商品。用牛肝SRM-1577检验了实验方法准确度。测得元素的放射性统计误差为10～30％。     

贵州万山汞矿地区人发中汞的含量及其赋存状态的XAFS原位研究

利用氢化物发生-原子荧光法测定了贵州万山汞矿地区人发中汞的含量。结果发现,该地区从事汞制剂操作的一线工人及居民的头发中汞含量远超过世界其它各地,其平均值为837μg/g,说明该地区受污染状况非常严重。通过XAFS法测试了3组汞含量较高的头发样品。由XANES谱得出,虽然3组头发中汞的含量不同,但其中汞离子的价态是一致的。比较样品与参考样品的EXAFS谱得出,虽然3组头发样品中汞含量不同,但汞与其最近邻原子的键长是一致的,从而其配位情况也可能是相同的。通过比较所有样品的谱图可看出,头发样品与Hg(GS)2的配位情况相似。     

用中子活化分析法研究产妇及其新生儿发中汞含量的相关性

以人发作“监示器”，用中子活化法分析了２７对北京海淀区产妇、婴儿发样中的汞含量，以研究汞在孕妇体内的转移及在新生儿体内的蓄积。发现婴儿发汞与母亲发汞呈显著线性正相关（ｒ＝＋０．８５６，Ｐ＜０．００１）；婴儿发汞平均值比母亲发汞值高１２％；母亲发汞有随怀孕时间的增加而逐渐降低的趋势。     

用质子激发X射线分析方法进行人发微量元素的分析研究

一、序言 质子激发X射线分析方法是瑞典人约翰逊在1970年首先提出来的。由于它具有灵敏度高、取样少、无损伤、快速、适用范围广等特点,使它在十余年中在生物医学、环境科学、地质、冶金、考古学和法学等领域得到了广泛的应用。我们应用质子激发X射线分析方法分析了人发中的微量元素。     

TOTAL AND METHYL MERCURY LEVELS IN HUMAN SCALP HAIRS

The contents of total and methyl mercury in scalp hair samples of 1179 fishermen living at a typical Hg-polluted region in Northeast China and 27 lying-in women and their new born babies in Beijing have been determined by instrumental neutron activation analysis,gas chromatography(electron coupling)and other techniques.Only 18 of all fishermen have the Hg contents above 5μg/g,which indicates that the Hg pollution there has been substantially alleviated.The longitudinal Hg patterns of the lying-in women show a gradually lowering tendency during pregnant period.Further,the Hg contents of the new-born babies are generally above or close to those of their mothers,confirming the mechanism that the methyl Hg,an organic species of Hg with high toxicity,is readily able to penetrate the placental barrier and accumulated in fetus.Thus,the mercury poison has occurred at the early stage of pregnancy.     

Internal elemental imaging by scanning X-ray fluorescence microtomography at the hard X-ray microprobe beamline of the SSRF: Preliminary experimental results

Synchrotron-based X-ray micro-fluorescence (μ-SXRF) is a non-destructive analytical technique and has been widely used to detect and quantify the elemental composition of samples in their natural state. To determine the internal elemental distributions within samples, X-ray fluorescence microtomography has been developed based on the hard X-ray microprobe at beamline BL15U1 of the Shanghai Synchrotron Radiation Facility (SSRF) in Shanghai, China. This technique was applied to image the cross-sectional distributions of multiple elements within a single human hair, and its validity was evaluated by comparing the results with the elemental maps of a thin hair section obtained using the well-established μ-SXRF mapping method. Elemental images of S, Ca, Mn, Fe, Cu, and Zn within a virtual slice of the hair were reconstructed after the tomographic measurements. The tomographic images of heavy elements like Fe, Cu, and Zn were found to be in good agreement with the corresponding μ-SXRF maps. Light elements, such as S, however, represented different patterns due to non-negligible self-absorption in the sample, and sophisticated correction algorithms accounting for such effects are required for obtaining qualitatively and quantitatively more accurate images. Compared to μ-SXRF mapping, X-ray fluorescence microtomography reduces the sample preparation requirements and has been demonstrated in this work as being a more ideal and effective imaging modality to non-destructively mapping out the internal distribution of heavy elements within samples at the micrometer scale at the SSRF.     

DISTRIBUTION OF SOME ELEMENTS IN HUMAN HAIR AND ORGANS DETERMINED BY NAA

Twenty four male autopsies were obtained from Shanghai. The samples of liver, lung, kidney cortex, brain and scalp hair were collected from the autopsies. The elements As, Br, Ca, Cd, Cl, Co, Cr, Cu, Fe, Hg, Mg, Mn, Na, Rb, 8, Se and Zn were determined by neutron activation analysis (NAA). The present study provides the elemental levels of different tissues for normal male adults. The distribution pattern of elements was discussed. Great difference on distribution of some elements in different tissues was observed.     

A quantitative basis for hair analysis using PIXE

The PIXE technique offers the possibility of scanning a single hair strand longitudinally with a millimetre proton beam for trace elements. However, the accuracy of the method has been questioned since the quantification of the mass concentration has been a serious problem. In this paper a specific beam-hair-detector geometry is assumed, and the correction factor accounting for the proton energy loss and the X-ray absorption in a regular hair is calculated. 43 hair segments from 8 individuals, ranging from 45 to 110 μm in in diameter were analyzed giving a mean value of 4.32% (standard deviation 0.25%) for sulphur, and a mean value of 149 ppm (standard deviation 35 ppm) for zinc. It is shown that the correction is important not only for the determination of the absolute elemental concentrations but also for the determination of their relative longitudinal distributions. The secondary corrections accounting for the inhomogeneous elemental distribution over the cross section and the irregular shape and/or the differing mass density of a hair are also calculated. It is concluded that the accuracy and precision of the PIXE method does not become considerably lower when it is applied to single hair strands, and accuracy and precision below 10% may be reached by implementing the procedure described.     

上海市长寿老人的头发微量元素谱特征

微量元素与人体健康和疾病有着密切的联系,特别是一些必需微量元素,它们通过参与酶、激素、蛋白质、核酸等的合成及代谢功能,对人体的生长、发育、衰老、死亡起着至关重要的作用。近年来,微量元素对人类寿命的影响已引起人们的注意。头发是一种化学组成均匀而稳定的物质,金属微量元素一旦与毛囊中的硫基(-SH)结合就被固定而不易被机体重新吸收或脱落。头发也和皮肤一样参与机体的代谢过程,是代谢的最终产物,头发中的元素浓度可反映人体内存在的元素的平均浓度。因而测定头发中的微量元素含量可为生长、发育和衰老研究提供重要信息。本工作的目的在于通过测定九十岁以上长寿老人发中的十种必需元素含量,探讨长寿老人的微量元素谱特征。