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1.
微量元素医学精要Ⅰ.微量元素的生理作用和体内平衡   总被引:33,自引:9,他引:33  
本文综述了微量元素的各种生理作用及其在体内的平衡与健康的关系。主要内容包括,微量元素的主要生理作用;体内元素平衡及其与健康的关系;必需微量元素的生理作用及其与健康的关系;锌缺乏症,碘缺乏症;铁缺乏症;儿童铅中毒,铝中毒。  相似文献   

2.
1-Methyl-2-pyrrolidinone (NMP) was used to extract samples of wood (forest residue) and coal; the extracts were analysed by inductively coupled plasma mass spectrometry (ICP-MS) using two different sample preparation methods, in order to identify trace elements associated with the organic part of the samples. A sample of fly ash was similarly extracted and analysed in order to assess the behaviour of the mineral matter contained within the wood and coal samples. 32% of the biomass was extracted at the higher temperature and 12% at room temperature while only 12% of the coal was extracted at the higher temperature and 3% at room temperature. Less than 2% of the ash dissolved at the higher temperature. Size exclusion chromatograms of the extracts indicated the presence of significant amounts of large molecular mass materials (>1000 mu) in the biomass and coal extracts but not in the ash extract. Trace element analyses were carried out using ICP-MS on the acid digests prepared by 'wet ashing' and microwave extraction. Sixteen elements (As, Ba, Be, Cd, Co, Cr, Cu, Ga, Mn, Mo, Ni, Pb, Sb, Se, V and Zn) were quantified, in the samples before extraction, in the extracts and in the residues. Concentrations of trace elements in the original biomass sample were lower than in the coal sample while the concentrations in the ash sample were the highest. The major trace elements in the NMP extracts were Ba, Cu, Mn and Zn from the forest residue; Ba, Cu, Mn, Pb and Zn from the coal; Cu and Zn from the ash. These elements are believed to be associated with the organic extracts from the forest residue and coal, and also from the ash. Be and Sb were not quantified in the extracts because they were present at too low concentrations; up to 40% of Mn was extracted from the biomass sample at 202 degrees C, while Se was totally extracted from the ash sample. For the forest residue, approximately 7% (at room temperature) and 45% (at 202 degrees C) of the total trace elements studied were in the extract; for the coal, approximately 8% (at room temperature) and 23% (at 202 degrees C) were in the extract. For the ash, only 1.4% of the trace elements were extracted at 202 degrees C, comprising 25% of Cd but less than 1% of Pb.  相似文献   

3.
陈然然  吴德华  王辛  龙成生 《色谱》2019,37(1):54-62
气相色谱-质谱法(GC-MS)是目前分析人体气味的主要技术手段,其不但可以分析人体气味的组成成分,还可以比较不同个体气味之间的差异。该文首先介绍了人体气味的提取和样品前处理的手段,随后对GC-MS在人体气味的采集及储存、成分分析及差异性研究、用于个体识别和健康表征等方面进行了综述,最后对GC-MS在人体气味分析中的发展趋势进行了展望。  相似文献   

4.
Metals perform many important physiological functions in the human body. The distribution of elements in different tissues is not uniform. Moreover, some structures can be the site of an accumulation of essential or toxic metals, leading to multi-directional intracellular damage. In the nervous system, these disorders are especially dangerous. Metals dyshomeostasis has been linked to a variety of neurological disorders which end up leading to permanent injuries. The multi-elemental composition of the human brain is still the subject of numerous investigations and debates. In this study, for the first time, the meninges, i.e., the dura mater and the arachnoid, were examined for their elemental composition by means of inductively coupled plasma mass spectrometry (ICP-MS). Tissue samples were collected post mortem from those who died suddenly as a result of suicide (n = 20) or as a result of injuries after an accident (n = 20). The interactions between 51 elements in both groups showed mainly weak positive correlations, which dominated the arachnoid mater compared to the dura mater. The study showed differences in the distribution of some elements within the meninges in the studied groups. The significant differences concerned mainly metals from the lanthanide family (Ln), macroelements (Na, K, Ca, Mg), a few micronutrients (Co), and toxic cadmium (Cd). The performed evaluation of the elemental distribution in the human meninges sheds new light on the trace metals metabolism in the central nervous system, although we do not yet fully understand the role of the human meninges.  相似文献   

5.
In order to ascertain water quality for human consumption, the evaluation of trace and ultra-trace elements in drinking waters of two Italian cities, Rome and Florence, is investigated together with the potabilization processes involved and the relative human exposure to the contaminants. Through a multi-elemental detection with no chemical treatment using Instrumental Neutron Activation Analysis and Proton-Induced X-ray Emission the concentration of 40 elements is determined. Basically, the concentrations of the investigated parameters in drinking waters were within the permissible limits of the World Health Organization drinking water quality guidelines and the Water Pollution Control legislation of Italian authorities. The Rome drinking water shows a chemical water composition quite similar to uncontaminated natural water: potentially toxic elements (e.g., Cr, Hg, Ni, and Sb) are present at very low concentrations whereas the levels of nutritionally essential elements are adequate and low levels of I and Se cannot be considered a cause of deficiency diseases. A multivariate statistical approach was used to identify both the origins and correlations among elements and the six different apportionments contributing to the water supply in Rome. For the drinking waters distributed in Florence, the element levels show a sufficiently good situation, except for Al (range 103–267 μg/L) that is present at reasonable concentrations for almost the entire population due to the hard potabilization procedure involving aluminum salts. The values of Metal Index (MI), that helps to quickly evaluate the overall quality of drinking waters, show a good drinking water quality in Rome (Fe is the only element to be considered critical) whereas in Florence the situation is influenced by Al levels. No relevant differences are found among Rome and Florence water composition and other Italian and world potable waters.This study can be considered a useful reference for studies aimed to highlighting toxicological, nutritional and environmental disease patterns.  相似文献   

6.
以不同特性煤浆的炉内燃烧固体残留物为研究对象,对取自炉内不同部位及沉积于硅碳棒和灰污探针上的典型燃烧灰的化学成分、矿物组成、元素分布及微观结构等进行分析研究。结果表明,水煤浆灰样中含Al、Fe、Ca的化合物和矿物的质量分数高于黑液浆,Na、K、S、Cl的情况与此相反。Fe的富集是造成水煤浆沾污结渣的根本原因。Na和Fe是引起黑液浆沾污结渣的主要矿物元素,Na的作用比Fe更大。黑液浆灰样中含有大量的霞石和硫酸钠等低熔融温度富钠化合物,Na是引起沾污结渣的根源。微观分析结果与实际燃烧状况是一致的,黑液浆结渣特性强于水煤浆,并且二者的灰沉积机理是不同的。  相似文献   

7.
The irregular shape of the human body and the non-uniformity of distribution of elements within the body makes absolute quantitation using in-vivo neutron activation relatively difficult. However, if the mass of an element can be assessed with reasonable accuracy, then a single measurement of a patient could reveal how far body content varied from normal. The determination of total body calcium is of importance in the study of bone disease. We have assessed the accuracy of measuring this quantity by varying the size of phantoms used for calibration and the distribution of element within these phantoms.  相似文献   

8.
通过观察煤灰柱在耐火材料表面随温度升高的形态变化和接触角的变化,来判断煤灰在耐火材料表面的润湿性;用扫描电镜(SEM)和能谱分析(EDS)等方法对煅烧煤灰过程中煤灰对耐火材料的侵蚀和渗透进行了观察测试,就渣样的形貌、耐火材料横断面的扫描图像及其元素变化进行了分析。结果表明,温度是影响煤灰在耐火材料表面润湿性和侵蚀性的重要因素;不同耐火材料的抗煤灰侵蚀不同,主要取决于耐火材料的组成和结构,其中结构致密度尤其重要;煤灰对耐火材料的侵蚀其实就是煤灰与耐火材料中各矿物元素互相侵蚀与渗透的结果,在侵蚀过程中还伴随着各种化学反应来抑制或促进侵蚀;煤灰在耐火材料表面的润湿性与煤灰对耐火材料的侵蚀性基本上表现出一致性。  相似文献   

9.
Instrumental neutron activation analysis (INAA) together with scanning electron microscopy (SEM) have been used in the study of fly ash from large electric power and heating plants. Two basic kinds of fly ash originating either from brown coal or heavy-oil combustion can be characterized both by morphology and trace element composition. INAA technique used consisted of both short (1 min) and long (2 h) activations to ensure the determination of 30–40 elements in each fly ash sample. The average composition and determination limits obtained by INAA for coal fly ash produced in several electric power plants burning two kinds of brown coal have been compared with those obtained for fly ash originating from heating plants burning heavy-oil. Coal fly ash showed much higher concentrations of many elements especially of Sc. La, Th, Cs, Ce, Sm, Rb and Al in comparison with oil fly ash. On the other hand, the latter contained relatively high concentrations of V and Ni. The results of INAA of fly ash samples can be used for the projection of efficient separating devices and for the evaluation and prediction of contamination levels in the vicinity of large emission sources.  相似文献   

10.
黑液水煤浆主要矿物元素在炉内的迁移和沉积行为研究   总被引:1,自引:1,他引:0  
为了研究黑液水煤浆的灰沉积机理,采用沿烟气行程从实验炉不同部位抽取空间灰粒和提取相应位置炉壁灰渣样相结合的方法,并与常规水煤浆相对比,研究了各主要矿物元素(Na、K、Si、Al、Fe、Ca)在烟气流中的迁移趋势和沉积特性。并且通过X射线衍射(XRD)和扫描电镜(SEM)等分析从微观角度进行了验证。结果表明,与常规水煤浆不同的是,Na、Si、Al的迁移和沉积是引起黑液水煤浆沾污结渣的主要矿物元素,灰沉积物中主要包括无水芒硝、霞石等低熔融温度富Na物相,而Fe的沉积是次要因素。  相似文献   

11.
以某电厂灰渣作为研究对象,分别对锅炉渣、粉煤灰和烟道灰3种材料对水环境的影响进行了试验,全面分析了灰渣的物理性质和化学成分。分别做了灰渣的浸出毒性试验、浸出剂的pH值对粉煤灰重金属浸出毒性试验,灰渣的腐蚀性、灰渣的淋溶、灰渣的沉降试验,从而得出燃煤电厂固体废物对水环境潜在的毒性影响。  相似文献   

12.
Coal and fly ash contain many elements. These elements exist in different forms which may change throughout the coal combustion process. There are several processes, including X-ray techniques and leaching techniques by which studies have attempted to assess the form of a particular element in a sample. This work focuses on determining the leachability of selected elements sequentially leached in four extraction solutions: water, 1 M ammonium acetate, 3 M hydrochloric acid and 50% hydrofluoric acid. The emphasis is on evaluating the steps involved in the leaching process with the mass recovery for each element being the basis for evaluation. The total amount of each element that will leach out under the given extraction condition is presented as a fraction of the total present in the material. The materials evaluated were NIST coal and fly ash standards. The elements measured in this study include aluminum, barium, beryllium, calcium, chromium, cobalt, iron, magnesium, manganese, nickel, potassium, sodium, strontium, vanadium and zinc.  相似文献   

13.
Richarz AN  Wolf C  Brätter P 《The Analyst》2003,128(6):640-645
In the human body, there exists over 200 different cell types, which differ in size and structure and have specialised functions in the organism. Therefore it can be assumed that these different cells also contain different proteins necessary to carry out the respective specialised functions. This supposed different metalloprotein composition in different human organs cannot be demonstrated by determination of total element concentrations. Therefore investigations of the different protein-bound forms of the elements were achieved by speciation analysis: The biomolecules were separated by size exclusion chromatography and the elements detected on-line in the eluate by a hyphenated inductively coupled plasma mass spectrometer (ICP-MS). For the interpretation of the obtained element profiles, an identification of the signals and their assignment to different metalloproteins was necessary. This identification was carried out by means of specific protein assays, i.e. enzymatic assays or immunochemical reactions, in collected fractions of the chromatographic separations. A comparison of the element binding pattern in cytosols of different human organs was then possible. The optimised method was applied to tissue cytosols of different human organs. As expected, the element patterns varied for different organs of the same patient and for the same organ of patients with different diseases. Metalloproteins and their bound metals could consequently be considered as biological markers for physiological differences or pathological changes in human tissues.  相似文献   

14.
The purpose of this research was to develop an optimized pretreatment procedure for toxic metals (Pb, Cd, Zn and Cu) content in fly ash from a municipal waste incinerator. In addition, modified sequential extraction procedures were used to characterize the chemical composition of the fly ash samples. The sequential extraction resolved the fly ash elements into the following chemical forms: soluble, exchangeable, carbonate, oxide, organic, and silicate compounds. Certified reference city waste incineration ash (BCR.176) was used as target ash samples. A H2O2+HNO3+HF mixed acid digestion solution with a low temperature evaporation procedure was selected as optimal for the fly ash digestion. The digested solution was analyzed by inductively coupled plasma mass spectrometry (ICP‐MS), which effectively determined the concentrations of the toxic metal elements in BCR.176. Except for Cd, the recovery of Pb, Zn, and Cu under H2O2+HNO3+HF digestion and their sequential extraction procedures were higher than 95%. The relative standard deviations (RSD) for recoveries of the four elements were within 10%. Furthermore, the sequential extraction procedure's results provided information on the potential mobility of the studied elements. Most of the Cd was bound to water‐soluble and carbonate material in the fly ash samples. Most of the Pb, Zn, and Cu was released to carbonates and bound to organic matter in the fly ash samples.  相似文献   

15.
微量元素在生命体中的最适浓度   总被引:3,自引:4,他引:3  
简要介绍了人体中的生命元素、微量元素和必需微量元素以及微量元素在人体中的生理功能和特征,指出微量元素摄入过量和不足所引起的不良后果。阐述了生命体中元素的最适浓度定律。  相似文献   

16.
随着人类社会的进步,经济的发展,生活水平的提高,环境的优劣逐步成为人们越来越关心的问题。自然环境的优劣,会直接影响人体的健康。自然环境的物质中所含常量元素和微量元素对维持人类生命,保护人体健康起到了一定的基础作用。  相似文献   

17.
头发元素分析的科学意义及医学应用价值   总被引:8,自引:3,他引:8  
对近100年来头发元素分析发展历史作了简要回顾,并从头发元素水平代表身体元素总体水平、头发元素含量可以准确测定,以及头发元素分析可用于医学诊断等三个方面论述了头发元素分析的生物学基础及临床意义,重点介绍了中国科学工作者在实验研究和临床实践中的探索和发现。科学实践证明,头发元素分析不仅为揭开古代头发神话提供了解释基础,也为头发的现代应用提供了可靠工具和科学依据。  相似文献   

18.
煤中15种微量元素在燃烧产物中的分配   总被引:21,自引:1,他引:21  
建立了燃煤中15种向量元素在悄灰和底灰中含量分布的经验公式,该公式可以估算煤中微量元素在燃烧产物中的分配及传输通量。煤中非挥发性元素大部分存在于底灰和飞灰中,挥发性元素进入大气的量较高。  相似文献   

19.
目的通过测定8批复方木鸡颗粒中无机元素的含量,拟从无机成分的角度探讨复方木鸡颗粒的特征元素。方法采用电感耦合等离子体质谱仪(ICP-MS),以半定量分析的方式测定8批次复方木鸡颗粒无机元素的含量,建立复方木鸡颗粒无机轮廓谱,并对其差异元素中的重金属元素和人体有益元素进行全定量测定,同时,采用聚类分析和主成分分析,对其特征元素进行评价。结果构建了复方木鸡颗粒无机元素的轮廓谱,通过聚类分析和主成分分析共找到6个特征元素,包括Ca、Mg、Mn、K、Cr、Ni。结论从无机成分的角度明确了复方木颗粒的特征元素,为进一步探究复方木鸡颗粒的药效研究提供理论依据。  相似文献   

20.
必需微量元素与人体健康   总被引:19,自引:10,他引:19  
人的躯体与各内脏都是由多种化学元素组成的,人体现已检出81种元素,其中有14种是人体必需微量元素。微量元素与人体健康密切相关。本文阐述了必需微量元素在人体内的生理功能,同时简述了必需微量元素的来源、微量元素间的相互作用以及必需微量元素缺乏或过量对人体产生的影响。  相似文献   

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