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1.
Seventeen elements, Al, Ca, Cd, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Na, Ni, P, Pb, V, and Zn (macroelements and trace elements) were investigated by Atomic Spectrometries on a particular wild edible mushroom collected in the central region of Argentina during 2 different years in the same season. The metal content profile in Suillus granulatus samples is given. The found quantities of Na, K, Ca, Mg, Fe, P, V, and Al were 0.40, 10.84, 0.48, 0.30, 0.57, 4.24, 0.18, and 1.23 g/kg dry weight, respectively. The levels of Li, Cu, Zn, Cd, Co, Ni, Cr, and Mn were 0.98, 23.02, 22.30, 0.26, 0.16, 1.17, 0.90, and 28.75 mg/kg dry weight, respectively. Pb was not detected at the investigated levels. The results indicate that the levels of metals in the analyzed samples are not considered to be a health risk. In order to demonstrate the validity of our method, a recovery study was performed with acceptable results.  相似文献   

2.
阿尔茨海默病(AD)是目前老年人最为关注的重要健康问题。中国55岁以上人群的AD患病率已超过2.0%,患病总人数在600万以上,中国已成为全球痴呆人数最多、速度增加最快的国家。至今人们对该病病因及其机制的了解仍然有限,亦无有效的药物可以阻止和治疗该病的发生和发展。该文在前人研究的基础上,全面总结并提出了该病病理的微量元素稳态障碍假设,详尽阐述了新学说的三个组成部分及四个方面的实践证据。  相似文献   

3.
阿尔茨海默病(AD)是目前老年人最为关注的重要健康问题。中国55岁以上人群的AD患病率已超过2.0%,患病总人数在600万以上,中国已成为全球痴呆人数最多、速度增加最快的国家。至今人们对该病病因及其机制的了解仍然有限,亦无有效的药物可以阻止和治疗该病的发生和发展。该文在前人研究的基础上,全面总结并提出了该病病理的微量元素稳态障碍假设,详尽阐述了新学说的三个组成部分及四个方面的实践证据。  相似文献   

4.
阿尔茨海默病(AD)是目前老年人最为关注的重要健康问题。中国55岁以上人群的AD患病率已超过2.2%,患病总人数在600万以上,中国已成为全球痴呆人数最多、速度增加最快的国家。至今人们对该病病因及其机制的了解仍然有限,亦无有效的药物可以阻止和治疗该病的发生和发展。该文在前人研究的基础上,全面总结并提出了该病病理的微量元素稳态障碍假设,详尽阐述了新学说的三个组成部分及四个方面的实践证据。  相似文献   

5.
阿尔茨海默病(AD)是目前老年人最为关注的重要健康问题。中国55岁以上人群的AD患病率已超过2.2%,患病总人数在600万以上,中国已成为全球痴呆人数最多、速度增加最快的国家。至今人们对该病病因及其机制的了解仍然有限,亦无有效的药物可以阻止和治疗该病的发生和发展。该文在前人研究的基础上,全面总结并提出了该病病理的微量元素稳态障碍假设,详尽阐述了新学说的三个组成部分及四个方面的实践证据。  相似文献   

6.
阿尔茨海默病(AD)是目前老年人最为关注的重要健康问题。中国55岁以上人群的AD患病率已超过2.0%,患病总人数在600万以上,中国已成为全球痴呆人数最多、速度增加最快的国家。至今人们对该病病因及其机制的了解仍然有限,亦无有效的药物可以阻止和治疗该病的发生和发展。该文在前人研究的基础上,全面总结并提出了该病病理的微量元素稳态障碍假设,详尽阐述了新学说的三个组成部分及四个方面的实践证据。  相似文献   

7.
8.
Various rice species, marketed in Austria, were analyzed for their Se, Cr, Ni, Rb, Fe, Co, Cs, Ag and Hg contents by neutron activation analysis. The concentration values found for Se ranged between 0.023 and 0.265 ppm, for Cr 0.540–1.875 ppm, for Ni 0.359–0.965 ppm, for Rb 1.604–6.400 ppm, for Fe 24.3–139.8 ppm, for Co 0.026–0.055 ppm, for Cs 0.016–0.032 ppm, for Ag 0.0006–0.0034 ppm, for Hg 0.003–0.023 ppm. Statistical analysis showed in the majority of cases that there is a significant difference in Se, Cr, Ni, Rb, Fe, Co, Hg contents but not in Cs. Highest values of Se and Fe were found in rice from Belgium /long seed, super patna/, whereas the Cr concentration was the highest in rice from Thailand /siam patna/. Ni was highest in rice from Uncle Ben's, Rb in Kresto from USA.  相似文献   

9.
The results of the analysis of approximately 100 soil samples for Na, Mg, Al, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, As, Sb, Ba, La, Sm, Eu, Dy, Lu, Hf, Th, and U by neutron activation analysis, in three soil horizons from four of the main agricultural parishes of Jamaica are presented. While there is some regional variation in the abundances, there are no statistically significant distributions of abundances across the horizons. The results for a few selected elements are compared with abundances in other countries.  相似文献   

10.
Skin tissue samples from 41 patients suffering from skin epitheliomas were analyzed by the PIXE method. Skin samples from the non-affected areas and blood serum were also analyzed for the same patients. The elements determined were K, Ca, Cr, Mn, Fe, Ni, Cu, Zn, Br, Rb, and Pb. Their concentrations in the healthy skin and the serum were normal. The concentrations in the lesions were nearly the same for both basal cell and squamus cell epitheliomas (BCE and SCC) except for higher zinc and lower bromine values in the BCE samples. However, substantial differences were observed between the affected and non-affected skin.Supported in part by the Hellenic Anticancer Society.  相似文献   

11.
Trace elements in different silica gels are determined by neutron activation analysis. The presence of 20 elements in the ppm range and of 15 elements in the ppb range is established in all silica gels; even in spherical material probably obtained via an organosilicium starting material. Removal of these elements by acid treatment before and after derivatization to a reversed-phase is studied. This is only partially effective. The resulting HPLC phases are, however, much better in cases where trace elements are detrimental. Even octadecyl derivatized silicagel can withstand boiling in 12 N hydrochloric acid without loosing significant amounts of bonded organic material.  相似文献   

12.
Elemental content of twenty medicinal plants used as tonic and for treatment of diabetes and simusitis were determined by INAA and XRF. Elemental determination was carried out in the raw samples, residues after boiling and the water soluble fractions. Samples were irradiated in TRIGA MkII reactor and counted using HPGe detector coupled to Personal Computer Analyzer (PCA) system. Bowen's Kale, NBS Pine Needles, NBS Citrus Leaves SRM were analysed to check the accuracy of the techniques used. Twenty elements were determined by both NAA and XRF. Arsenic was only detected inLabisia pothoina andDracontomelon dao with a concentrations of 0.40 mg/kg and 0.60 mg/kg respectively. Antimony was found in eleven samples with a concentration of <0.20 mg/kg. Al, Br, Ca, Cl, K, Mn, Na and Rb were detected in all samples whereas Mg and Zn were present in all samples exceptCinnamomum sp. Highest concentration of Br (190 mg/kg), Cl (11805 mg/kg), Co (0.50 mg/kg), Fe (1642 mg/kg), K (36788 mg/kg), Mn (325 mg/kg), Na (126 mg/kg), Rb (197 mg/kg), Sc (0.18 mg/kg) and Zn (3551 mg/kg) were observed in the tuber ofLasia aculeata. Less than 70% and 50% of the elements contained inCallicarpa longifolia andEurycoma longifolia were obtained respectively from water by boiling.  相似文献   

13.
Instrumental Neutron Activation Analysis (INAA) and Proton-Induced X-ray Emission (PIXE) analysis (employed as a complementary technique) have been used to determine the concentration of 11 elements in blood samples and its components erythrocytes and plasma obtained, from three groups of subjects in Nigeria viz: sickle cell anaemia (SCA) subjects, subjects with sickle cell trait and normal control subjects. The results suggest that SCA subjects have significantly higher concentrations of Na, Cl, Ca and Cu in their whole blood and erythrocytes and a higher concentration, of Cl and Cu in their plasma relative to the control subjects. Furthermore, a significantly lower concentration of K, Fe, Zn, Se, Br and Rb were found in the whole blood and erythrocytes of the SCA subjects as compared to the controls while the concentration of K and Fe in the plasma of the SCA subjects were however, found to be significantly higher than that of the control group. The study also shows that there was no significant differences between the concentration of these 11 elements in the group with sickle cell trait and the normal control group.  相似文献   

14.
Atmospheric particulate material collected in Ankara was analyzed by instrumental neutron activation analysis. The results are interpreted with respect to trace element concentrations of the earth's crust. Volatile elements such as As, Sb, Zn, Br and Hg are highly enriched suggesting noncrustal origin. Enrichment factors increase with decreasing particle size.Supported in part by the Scientific and Technical Research Council (TÜBITAK) of Turkey.  相似文献   

15.
16.
The trace element contents of Taiwanese diet were determined using conventional neutron activation analysis. Sample were prepared with duplicate portion technique by collecting food items ate and drank during a 3 day period in winter. Samples were homogenized, freeze-dried, and elemental concentration of trace elements were determined by instrumental neutron activation analysis. The interference from fast neutron induced reactions were corrected. Concentrations and daily dietary intake of the elements were compared with those collected in the summer, resulting less daily intake of K, Ca, Mn, Fe, and Zn among Taiwanese than the values recommended by WHO and RDA. Alarming low intake of Fe for females and Zn among Taiwanese were indicated.  相似文献   

17.
The aim of the International Measurement Evaluation Programme (IMEP) is to give an objective picture of state-of-the-practice analytical measurements by comparing them to a reference value obtained by a primary method of measurement. The referencevalue is therefore as traceable to the SI system of measurements as can presently be achieved and is independent of human or political decisions. Thus a large scale field test is made to achieve (international) comparability of measurements by comparing them with an independent metrologically established value. In the fourth measurement round, IMEP-4, three trace elements, Li, Cu and Zn, at three different levels in (bovine) serum were measured by about 12 participating laboratories using their routine methods. The (coded) results are graphically reported and compared to certified reference values established by an isotope-specific method, isotope dilution mass spectrometry, defined as a primary method of measurement by the Consultative Committee on Amount of Substance. Results indicate a spread of more than ±50%, asymmetrically distributed around the reference value with its own uncertainty range, although the self-declared accuracy of the laboratories was 5–10%. Self-assessment by participants of their analytical capabilities does not show a high correlation between self-rating ("more experienced" or "less experienced") and actual performance. In the way they have been applied, all methods seem to produce results of approximately the same quality.  相似文献   

18.
19.
Instrumental neutron activation analysis /INAA/ was applied to measure trace elements in head hair of 19 patients with impaired renal function /14 males and 5 females/ and of 40 normal individuals /20 males and 20 females/. It was the aim to use head hair as a possible indicator of total body trace elements status and to investigate whether significant changes occur as a result of chronic hemodialysis. The elemental concentrations of 20 elements /i.e. Na, Mg, Al, Cl, K, Ca, V, Mn, Fe, Co, Cu, Zn, As, Se, Br, Ag, Cd, Sb, I and Au/ are presented and compared with published data. The present study revealed that the hair of the dialysis patients contained about ten times more iodine than that of the control group. No significant differences were observed for the other elements measured, except for sodium and antimony.  相似文献   

20.
Trace elements distribution in the Amazon floodplain soils   总被引:1,自引:0,他引:1  
Neutron activation analysis was performed on aluvial soil samples from several sites on the floodplains of the Amazon River and its major tributaries for trace elements determination. The spatial and temporal variations of chemical composition of floodland sediments in the Amazon basin are discussed. No significant difference was found in trace elemental distribution in the floodland soils along the Amazon main channel, even after the source material has been progressively diluted with that from lowland draining tributaires. It was also seen that the average chemical composition of floodplain soils compares well with that of the suspended sediments.  相似文献   

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