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31.
红珍珠降糖胶囊是具有显著降低血糖水平,确定糖尿病患者康复的绿色营养保健食品。通过红珍珠降糖胶囊中Cr、Mn、Cu、Zn、Mg等微量元素的分析测试以及与青海小麦、膳食日摄取量等对比研究,表明红珍珠降糖胶囊富含涉及糖尿病的微量元素,在降低血粮糖水平方面具有十分重要的营养学、功效学作用和意义。  相似文献   
32.
l,l′-dimethylferricinium (DMFe+),a stable and pH-insensitive blue dye, was prepared via enzymatic oxidation of a 1,1′-dimethylferrocene (DMFe):2-hydroxypropyl-β-cyclodextrin (HPCD) watersoluble inclusion complex, using bilirubin oxidase immobilized onto porous aminopropyl glass beads via glutaraldehyde activation. In the presence of glucose, DMFe+ was reduced to DMFe by reacting with the reduced glucose oxidase (FADH2), and the absorbance decrease was followed at 650 nm. In acetate pH 5.2 buffer, the response to glucose in blood serum was nonlinear, especially in the low concentration range, because of a competition for the reduced glucose oxidase between the DMFe+ dye and oxygen. At this pH, endogenous ceruloplasmin was also observed to oxidize residual DMFe (16%) in the dye preparation, causing an increase in absorbance at 650 nm. An assay protocol was then developed using maleate buffer, pH 6.5, to overcome these interferences as well as mutarotation of α-D-glucose. The results obtained for glucose in the blood serum samples agreed well with those of the reference hexokinase/glucose-6-phosphate dehydrogenase method.  相似文献   
33.
A cobalt hexacyanoferrate (CoHCF) nanoparticle (size ca. 60 nm) chemically modified electrode (CME) was fabricated and the electrochemical behavior of hemoglobin (Hb) at this nanosized CoHCF CME was studied. In comparison with a bare glassy carbon electrode (GCE) and a general CoHCF CME electrodeposited in a traditional manner, the present nanosized CoHCF CME performed efficiently electrocatalytic reduction for Hb with relatively high sensitivity, stability, and longlife, Combined with liquid chromatography (LC), the nanosized CoHCF CME was used as the electrochemical detector of Hb in the established flow injection analysis-electrochemical determination (FIA-ECD) system. The peak current was a linear function of concentrations in the range from 2.5×10^-8 to 5.0×10^-6mol/L for Hb, with detection limit of 1.4×10^-8 mol/L. The FIA-ECD system has been successfully applied to assess the Hb content of clinic blood samples with advantages of sensitiveness, speediness, easy control and small sample-consumption.  相似文献   
34.
Hydrogen peroxide in basic media is proposed as a means for dissolving whole blood samples to be analyzed by electrothermal atomization atomic absorption spectrometry, ET AAS. Approximately 2 g of the whole blood sample were directly weighed in a 150 mL volumetric flask; 3 mL of a NaOH 0.2 mol L−1 solution, two drops of 1-octanol, as an antifoaming agent, and 1 mL of 30% volume hydrogen peroxide were added to the flask to promote oxidation. The solution was then manually shaken and after approximately three minutes of shaking, a clear solution, with no apparent suspended solids or greasy layers, was obtained. Distilled-deionized water was used to complete the volume. Ten μL of the resulting solution along with 10 μL of a solution containing 5000 mg L−1 of NH4H2PO4 and 300 mg L−1 of Mg(NO3)2 as a modifier, were injected into transversely heated graphite tubes for lead determination. Both aqueous standards and standard addition calibration curves produced results not significantly different at a 95% confidence limit level. Accuracy of the measurements was assessed by analysis of the IAEA A-13 (concentration of trace and minor elements in freeze dried animal blood) standard reference material containing 0.18 mg L−1 lead on a dry basis and by means of recovery tests. Analysis of the IAEA A-13 standard produced 0.17 ± 0.02 mg L−1 lead on a dry basis; recovery tests afforded values from 95 to 105%. Ten consecutive measurements of a 5 ppb lead solution gave a characteristic mass of 47.2 pg and a (3S) detection limit of 1.77 μg L−1 Pb. Results obtained from analysis of whole blood samples of volunteer donors covered a lead concentration range between 8 and 21 μg L−1 with a mean value of 11.9 ± 4.7 μg L−1.  相似文献   
35.
血橙中微量元素的测定   总被引:2,自引:0,他引:2  
采用电感耦合等离子体原子发射光谱仪(ICP-AES),对血橙果肉汁、皮、籽中10种微量元素进行了测定。结果表明,血橙果肉汁、皮、籽中含有Ca、Mg、Fe、Zn、Mn、Cu、Ni等丰富的人体必需微量元素,且血橙果皮、籽中的微量元素含量普遍高于果肉汁中的微量元素的含量,这为血橙药效功能的进一步研究和资源综合开发利用提供一定的科学依据。  相似文献   
36.
526例儿童指血微量元素检测结果分析   总被引:8,自引:0,他引:8  
为了解吐哈油区婴幼儿体内钙、铁、锌、铜、镁的含量,使用多通道原子吸收光谱仪对门诊体查的526例0~7岁幼儿指血检测了钙、铁、锌、铜、镁。结果表明,各个年龄组中缺铁均居第一位,缺钙居第二位,缺锌居第三位,年龄越小,这3种元素含量越低。提示婴幼儿生长发育快,易缺钙,铁,锌元素,年龄越小,越易缺乏。  相似文献   
37.
Ammonia absorption by and desorption from lithium chloride at different pressures has been studied using high-pressure differential scanning calorimetry, for application in a high-lift high temperature chemical heat pump. The measurements were performed under isobaric as well as under isothermal circumstances. Clausius–Clapeyron plots were constructed and used to calculate the thermodynamic parameters and to determine the stability regions of the different complexes. Controversies in literature as to the real existing phases are resolved.  相似文献   
38.
A new chemical method is reported for the determination of total fluoride in complex liquids and suspensions, such as fruit juices, urine, serum and blood. It is based on the formation of the A1F radical in a graphite furnace afterin situ oxygen-assisted ashing of the untreated sample. The absorbance of this radical is measured at 227.45 nm. The method is relatively easy to use and provides a low detection limit (14 ng/ml) and reasonable reproducibility (5–10%).  相似文献   
39.
An extract of crystal violet-tetrachloroferrate(III) in nitrobenzene was used to prepare a tetrachloroferrate(III)-selective liquid membrane electrode with a poly(vinyl chloride) support. The optimal conditions to determine 2.5 × 10–5 – 5.0 × 10–2 M iron(III) as tetrachloroferrate(III) (anionic slope 56 mV/decade, detection limit 7.9 × 10–6 M) were found to be 4.0–5.5.M total chloride in 0.75–1.5M hydrochloric acid. The electrode was reliably applied to determine iron in human blood, haematite and mineralized vitamin syrup by direct potentiometry, standard and sample additions as well as standard subtraction techniques.  相似文献   
40.
采用液-液提取方法及GC—FPD定量、GC—MS定性检测手段,对血液样品中毒鼠强的提取和检测方法进行了研究。时提取毒鼠强的溶剂类型、溶剂用量及质谱分析参数等因素进行了考察,建立了一种回收率高、重现性好、灵敏度佳、干扰少的毒鼠强分析方法。毒鼠强工作曲线的线性范围为0.01-0.2μg/μL,相关系数r=0.9999,空白血液的加标平均回收率为93.6%,测定结果的相对标准偏差为5.27%。该方法满足司法鉴定中生物样品的定性、定量检验要求。  相似文献   
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