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81.
罗美英 《广东微量元素科学》2004,11(6):20-22
为评价口服氨基酸螯合钙胶囊配合胱氨酸片对脱发患者的临床疗效 ,将 1 2 0例脱发患者随机分为治疗组与对照组。治疗组 60例用氨基酸螯合钙胶囊 ( 1g/d ,1粒 ,qd ,PO)和胱氨酸片( 3 0 0mg/d ,3次 /d ,PO)治疗 ,对照组 60例用胱氨酸片 ( 3 0 0mg/d ,3次 /d ,PO)治疗 ,两组用药均为 1 2周。结果表明 ,治疗组与对照组相比 ,治疗组较对照组的临床症状有明显改善 ,头发中微量元素锌、铁、钙的含量有显著性差异 (P <0 0 5 )。脱发患者经补充有效的所需微量元素配合胱氨酸治疗收到良好效果。 相似文献
82.
Aaron Goldman Frank J. Murcray Frank H. Murcray David G. Murcray Curtis P. Rinsland 《Mikrochimica acta》1988,95(1-6):409-415
Simultaneous total column amounts of a number of minor and trace atmospheric gases above the South Pole in December 1980 and December 1986 have been deduced from analysis of high resolution solar absorption spectra recorded (by F. J. M. and F. H. M.) from Amundsen-Scott South Pole Station. These spectra also contain some limited information on the vertical profiles of the observed atmospheric gases.The data sets were recorded with a Bomem Michelson-type interferometer and analyzed with a spectral least-squares fitting procedure, utilizing the best available spectroscopic line parameters and absorption cross sections. Because the same instrument, line parameters, and analysis method have been used in analyzing the December 1980 and December 1986 data sets, the precision in comparing the column amounts from these two dates is rather high, about 10–20% for the stronger absorbing gases. For this reason, it has been possible to quantify or determine upper limits for differences between the December 1980 and December 1986 total column amounts, of a number of atmospheric gases including O3, N2O, HNO3, CO2, CH4, and CF2C1
2 (CFC 12). In addition, vertical column amounts for a number of atmospheric gases covered only in the December 1986 observations have been derived, including HC1, NO, NO2, and C2H6. Some of these results will be discussed here. The HC1 measurements are especially interesting since the observed amounts are higher than expected from observations made at lower latitudes in the northern and southern hemispheres. 相似文献
83.
84.
A simple and accurate digestion method using nitric acid, perchloric acid and hydrogen peroxide has been developed for use in trace analysis for heavy metals in vegetables by differential pulse anodic stripping voltammetry. The recovery of the metals from the samples is lower if the hydrogen peroxide is omitted from the digestion mixture. Standard reference materials have been analysed satisfactorily by this method. 相似文献
85.
为了研究白血病骨髓移植病人全血微量元素铜的变化及其意义 ,用原子吸收光谱法检测了正常对照组与白血病骨髓移植患者预处理前及移植后骨髓空虚期全血微量元素铜的含量。结果表明 ,正常对照组全血铜浓度与白血病骨髓移植患者预处理前全血铜浓度差异无显著性 (P >0 0 5 ) ,而与骨髓空虚期全血铜浓度有显著性差异 (P <0 0 5 ) ,说明白血病缓解后血铜接近正常对照组水平 ,而白血病骨髓移植患者预处理后骨髓空虚期全血铜含量高于正常对照组 ,说明预处理影响微量元素铜的代谢 ,本文就其影响机理进行了研究 相似文献
86.
猴头菇微量元素含量的分析 总被引:5,自引:6,他引:5
用电感耦合等离子体发射光谱仪(ICP-AES)测定了湛江市栽培的猴头茹微量元素的含量,发现其磷、硫、钙、镁、锌、铁、铜等元素的含量都比较丰富,并讨论了这些有益元素与人体健康的关系。 相似文献
87.
目的测定中草药木贼中微量元素的含量。方法用湿法消化及于法灰化两种方法处理样品并进行了比较,用火焰原子吸收法测定了中草药木贼中7种微量元素的含量。结果测定结果湿法的RSD在0.5%~3.0%,干法的RSD在0.5%-7.5%之间。结论湿法处理金属离子损失小,测量精密度更好。木贼中微量元素的含量由高到低顺序为:Mg,Fe,Mn,Zn,Cu,Ph,Ni。 相似文献
88.
AbstractHerein the bioaccessibility of Mn, Cu, Zn, Cd, and Pb, selected from essential and toxic elements, was determined in commercially sold vegetable purees intended for infant and toddler consumption. Chemical fractionation studies using water, acetone, diethyl ether, chloroform:methanol, and n-hexane were employed to predict the importance of the protein and lipid parts of a matrix to assess the bioaccessibility data. In addition, in-vitro gastrointestinal digestion was performed to determine the bioaccessibility of the elements using a five level, three factor central composite design (CCD) to maximize the elemental solubility. The total elemental concentrations in all of the fractions were determined by inductively coupled plasma – mass spectrometry (ICP-MS). Based on the consumption of one jar of vegetable/rice-based baby food, Zn was 1.3% of the recommended dietary allowance and Mn was 4.2% of the adequate intake level, while Cu was almost 100% of the adequate intake level. Additionally, Pb was always below the detection limit and Cd was sometimes under the detection limit for the percent bioaccessibility. However, in some samples, Cd was as high as 80% of the tolerable weekly intake level depending on the body weight. 相似文献
89.
Jene D. Cyran Ellen H. G. Backus Marc‐Jan vanZadel Mischa Bonn 《Angewandte Chemie (International ed. in English)》2019,58(11):3620-3624
Small organic molecules on ice and water surfaces are ubiquitous in nature and play a crucial role in many environmentally relevant processes. Herein, we combine surface‐specific vibrational spectroscopy and a controllable flow cell apparatus to investigate the molecular adsorption of acetone onto the basal plane of single‐crystalline hexagonal ice with a large surface area. By comparing the adsorption of acetone on the ice/air and the water/air interface, we observed two different types of acetone adsorption, as apparent from the different responses of both the free O?H and the hydrogen‐bonded network vibrations for ice and liquid water. Adsorption on ice occurs preferentially through interactions with the free OH group, while the interaction of acetone with the surface of liquid water appears less specific. 相似文献
90.
传染性单核细胞增多症患儿微量元素分析 总被引:2,自引:1,他引:2
为探讨微量元素与传染性单核细胞增多症的关系,对30例传染性单核细胞增多症患儿及30例健康儿童进行了全血6种微量元素检测分析。结果表明,传染性单核细胞增多症患儿的全血锌、铁含量低于健康儿童(P0.05),而血铜、钙、镁、铅等无明显变化。提示传染性单核细胞增多症患儿部分微量元素含量存在异常。 相似文献