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1.
对65例消化系癌患者与80例对照人群作了血清Mo、Se、Mn、Cu、Zn的测定.经方差分析,四种消化系癌血清Se含量均低于对照人群(P值均<0.01),而在四种消化系癌之间的区别无显著意义(P值均>0.05).  相似文献   

2.
对43例胃癌病人测定了发中Zn、Cu、Fe、Mn、Ca、Mg六种元素,结果:胃癌组发中Cu、Fex±SD值较健康对照组升高,P<0.05,有显著性差异.Zn、Ca、Mgx±SD值较健康组降低,P<0.05、<0.01、<0.01,差异有显著性和高度显著性.MUx±SD值与健康对照组近似,P>0.05,差异无显著性.胃癌组Zn/Cu比值较健康对照组降低,P<0.01,差异高度显著性;胃癌组Zn/Fe比值与健康组近似,P>0.05,差异无显著性.Fe升高,Mn、Zn降低是胃癌的危险因素,Mn有抗癌抑癌作用,Fe、具有强烈催化自由基及过氧化反应的能力.发中微量元素测定可作为临床胃癌病人辅助诊断参考.  相似文献   

3.
用原子吸收光谱法测定了70例健康老年人、30例健康成年人和30例老年高血压病人血清中Cu、Zn、Fe、Mn、Ca、Mg6种元素的含量.结果表明,健康老年人组与健康成年人组(对照组)相比,除Fe以外,Cu、Zn、Mn、Ca、Mg均有显著性差异;与老年高血压病人组相比,除Mg以外,Cu、Zn、Fe、Mn、Ca均有显著性差异.我们认为稳定的Cu/Zn比值及较高的血Mg水平是健康老年人未发生心血管疾病及糖尿病的重要原因之一,而高Cu、高Ca及显著偏高的Cu/Zn比值,则是发生高血压的一个重要原因。  相似文献   

4.
通过EPM-810Q电子探针扫描分析电镜,对在治疗中53例结核患者头发Mg、Al、Cd、Ca、Cr、Mn、Fe、Cu、Zn、Pb、Se11种元素含量进行分析,并与健康人头发比较。结果表明:结核组中Ca、Zn元素含量低于健康组,Cu、Fe元素含量高于健康组(P〈0.01)。  相似文献   

5.
观察了45例新生儿高胆红素血症患儿光疗(蓝光)前后血清15种元素的变化。结果发现患儿在光疗后12种元素含量较光疗前降低,尤其是Cu、Fe降低明显,t值分别为2.09,2.73,P〈0.05,P〈0.01,有显著性差异,Zn、Ca虽有所下降,但无统计学意义。推测Cu、Fe降低的原因与肠道、尿液及汗液排泄增加有关。提示对光疗后的高胆血症病人应注意及时补充Cu、Fe等微量元素,以保证小儿生长发育的需要。  相似文献   

6.
用催化极谱法测定72例慢性支气管炎患者及50例健康者人发及血清中锌、铁、铜、锰四种微量元素的含量。结果表明,Zn、Fe元素的含量比对照组低,并表现有显著性差异(P〈0.01),Cu、Mn元素的含量在两组之间无显著性差异(P〉0.05)。  相似文献   

7.
用自制的四种全芳香族热致液晶聚合物BP LCP、BPM LCP、BPA LCP、BPS LCP与热塑性树脂聚砜(PSF)熔融共混,制备了一系列原位复合材料.研究了所得材料的微观形态、热性能、力学性能等,结果显示:四种液晶聚合物中,BP LCP,BPS LCP在所用加工条件下可在PSF中取向成纤,而且这两种共混物断面上存在皮 核效应;BPM LCP和BPA LCP未成纤,均以球状存在于PSF中.这四种液晶聚合物与PSF的相容性较差,各共混物的Tg均分别接近于二纯组分的Tg值,SEM照片上明显的相界面也能说明以上问题.液晶聚合物对PSF有增强作用,但增强效果不很显著,这可能是二者相容性较差所致  相似文献   

8.
儿童多动症与微量元素关系的探讨   总被引:8,自引:1,他引:8  
为了探讨儿童多动症与微量元素的关系,测定了72例多动症患儿头发中的六种元素Zn、Cu、Pb、Cr、Fe、Ca含量,并将其与正常儿童进行比较,结果表明:多动症组Cu显著低于正常组,P〈0.01,多动症组Zn显著低于正常组,P〈0.05,多动症组Pb显著高于正常组,P〈0.05。提示调整患儿体内微量元素平衡可作为治疗儿童多动症的辅助方法。  相似文献   

9.
通过25种(158例)正常人组织和29种(168例)癌瘤组织中As,Se、Pb,Cd,Co,Zn,Cu、Hg、Fe和Mg等十种元素量分析,发现癌瘤组织中Cd、Pb,As三种元素高于正常组织,而Se和Zn两种元素与致癌元素的比值进行显著性测验,结果癌组明显高于正常组。  相似文献   

10.
应用等离子体发射光谱法(ICP-AES)对精神分裂症急性期男病人48例,女病人30例和慢性期男病人50例,女病人30例,检测头发中Zn、Fe、Cu、Ca、Mn5种元素,并与158名男女正常人作对照,发现无论是急性期还是慢性期,男女病人的Cu、Mn两元素的含量,均显著低于正常人(P<0.05~0.001).  相似文献   

11.
传统藏药材高原香薷的矿质元素分析   总被引:2,自引:0,他引:2  
对传统藏药材香薷中高原香薷种的17种微量元素进行了分析。结果表明,在高原香薷中人体必需微量元素Cu、Zn、Fe、Mn、Co、Ni、Se等含量较高,尤其以Cu、Fe、Mn元素的含量为高。Na、Ca等宏量元素含量亦较高。  相似文献   

12.
Y Chang  QS Li  Y Xie  RB King 《Inorganic chemistry》2012,51(16):8904-8915
Recent experimental work (2010) on (Cy(3)P)(2)Pt(BO)Br indicates that the oxygen atom of the boronyl (BO) ligand is more basic than that in the ubiquitous CO ligand. This suggests that bridging BO ligands in unsaturated binuclear metal carbonyl derivatives should readily function as three-electron donor bridging ligands involving both the oxygen and the boron atoms. In this connection, density functional theory shows that three of the four lowest energy singlet Fe(2)(BO)(2)(CO)(7) structures have such a bridging η(2)-μ-BO group as well as a formal Fe-Fe single bond. In addition, all four of the lowest energy singlet Fe(2)(BO)(2)(CO)(6) structures have two bridging η(2)-μ-BO groups and formal Fe-Fe single bonds. Other Fe(2)(BO)(2)(CO)(n) (n = 7, 6) structures are found in which the two BO groups have coupled to form a bridging dioxodiborene (B(2)O(2)) ligand with B-B bonding distances of ~1.84 ?. All of these Fe(2)(μ-B(2)O(2))(CO)(n) structures have long Fe···Fe distances indicating a lack of direct iron-iron bonding. One of the singlet Fe(2)(BO)(2)(CO)(7) structures has such a bridging dioxodiborene ligand with cis stereochemistry functioning as a six-electron donor to the pair of iron atoms. In addition, the lowest energy triplet structures for both Fe(2)(BO)(2)(CO)(7) and Fe(2)(BO)(2)(CO)(6) have bridging dioxodiborene ligands with trans stereochemistry functioning as a four-electron donor to the pair of iron atoms.  相似文献   

13.
中老年糖尿病轻重度患者血清中锌铜铁的分析   总被引:1,自引:0,他引:1  
对128例中老年糖尿病患者血清中微量元素锌、铜、铁的含量进行了分析,并与正常对照组进行了比较。结果表明,血糖正常组和高血糖组的糖尿病患者血清锌水平均低于正常对照组,且差异非常显著,两病例组间亦有显著差异。血清铜水平则均高于对照组,三组间差异非常显著。血清铁水平虽均低于对照组,但无统计学上的显著意义。这说明血清中锌、铜、铁的测定可作为该种疾病诊断的参考指标,并提示糖尿病患者应以适当补充锌、铁制剂为辅助治疗手段。  相似文献   

14.
There is evidence that the interaction of the α-ketol group of the Doxorubicin and Epirubicin anti-cancer drugs with Fe(iii) generates hydroxyl radicals under aerobic conditions, causing cardiotoxicity in patients. Considering that the formation of DNA adducts is one of the main targets of Anthracycline drugs, we have in the present study characterized several [Anthracycline-DNA]Fe(iii) complexes with respect to their stability and Fe(iii) coordination, by means of MD simulations. Iron is found to coordinate well to the drugs containing an α-ketol group, this being the only group of the drug that binds to the metal. The complexes containing an α-ketol group, [Doxorubicin-DNA]Fe(iii) and [Epirubicin-DNA]Fe(iii), thus show greater stability than those not containing it, i.e., [Daunorubicin-DNA]Fe(iii), [Idarubicin-DNA]Fe(iii) and [5-Imino-Daunorubicin]Fe(iii). Metal attachment to the α-ketol group is furthermore facilitated by the phosphate groups of DNA. The coordination to iron in the [Doxorubicin-DNA]Fe(iii) system is smaller than that found for the [Epirubicin-DNA]Fe(iii) system, and the corresponding number of coordinating waters in the former is larger than in the latter. This may in turn result in higher hydroxyl radical production, thus explaining the increased cardiotoxicity noted for Doxorubicin.  相似文献   

15.
Accurate and precise determination of the redox state of iron (Fe) in spinels presents a significant challenge due to their refractory nature. The resultant extreme conditions needed to obtain complete dissolution generally oxidize some of the Fe(II) initially present and thus prevent the use of colorimetric methods for Fe(II) measurements. To overcome this challenge we developed a hybrid oxidimetric/colorimetric approach, using Ag(I) as the oxidimetric reagent for determination of Fe(II) and 1,10-phenanthroline as the colorimetric reagent for determination of total Fe. This approach, which allows determination of Fe(II) and total Fe on the same sample, was tested on a series of four geochemical reference materials and then applied to the analysis of Fe(Ni) spinel crystals isolated from simulated high-level-waste (HLW) glass and of several reagent magnetites. Results for the reference materials were in excellent agreement with recommended values, with the exception of USGS BIR-1, for which higher Fe(II) values and lower total Fe values were obtained. The Fe(Ni) spinels showed Fe(II) values at the detection limit (ca. 0.03 wt% Fe) and total Fe values higher than obtained by ICP-AES analysis after decomposition by lithium metaborate/tetraborate fusion. For the magnetite samples, total Fe values were in agreement with reference results, but a wide range in Fe(II) values was obtained indicating various degrees of conversion to maghemite. Formal comparisons of accuracy and precision were made with 13 existing methods. Accuracy for Fe(II) and total Fe was at or near the top of the group. Precision varied with the parameter used to measure it but was generally in the middle to upper part of the group for Fe(II) while that for total Fe ranged from the bottom of the group to near the top.  相似文献   

16.
Roussin黑盐与重氮盐反应,可以得到络合物[Fe-2S_2(C_6H_4F)_2(NO)_4]。它是一种暗红色的晶体,属于三斜晶系,空间群P_~-,晶胞参数a=10.217 4),b=10.143(1),c=8.955(1),α=105.68(4)°,β=99.91(2)°,Υ=83.44(2)°,Z=2。应用X射线衍射方法测定晶体结构。由重原子法解出结构,并经全矩阵最小二乘法修正,R=0.029。单胞中的两个分子以对称心相连系。Fe原子为四面体配位,两个-SR基团上的S原子以桥键与两个Fe原子构成Fe_2S_2的菱形平面,四个-NO基则分别与两个Fe原子配位。  相似文献   

17.
A bridging carbonyl intermediate with key structural elements of the diiron sub-site of all-iron hydrogenase has been experimentally observed in the CN/CO substitution pathway of the {2Fe3S} carbonyl precursor, [Fe(2)(CO)(5){MeSCH(2)C(Me)(CH(2)S)(2)}]. Herein we have used density functional theory (DFT) to dissect the overall substitution pathway in terms of the energetics and the structures of transition states, intermediates and products. We show that the formation of bridging CO transitions states is explicitly involved in the intimate mechanism of dicyanation. The enhanced rate of monocyanation of {2Fe3S} over the {2Fe2S} species [Fe(2)(CO)(6){CH(2)(CH(2)S)(2)}] is found to rest with the ability of the thioether ligand to both stabilise a mu-CO transition state and act as a good leaving group. In contrast, the second cyanation step of the {2Fe3S} species is kinetically slower than for the {2Fe2S} monocyanide because the Fe2 atom is deactivated by coordination of the electron-donating thioether group. In addition, hindered rotation and the reaction coordinate of the approaching CN(-) group, are other factors which explain reactivity differences in {2Fe2S} and {2Fe3S} systems. The intermediate species formed in the second cyanation step of {2Fe3S} species is a mu-CO species, confirming the structural assignment made on the basis of FT-IR data (S. J. George, Z. Cui, M. Razavet, C. J. Pickett, Chem. Eur. J. 2002, 8, 4037-4046). In support of this we find that computed and experimental IR frequencies of structurally characterised {2Fe3S} species and those of the bridging carbonyl intermediate are in excellent agreement. In a wider context, the study may provide some insight into the reactivity of dinuclear systems in which neighbouring group on-off coordination plays a role in substitution pathways.  相似文献   

18.
Precise 56Fe/54Fe and 57Fe/54Fe isotopic ratios on human red blood cell (RBC) samples have been measured using multiple collector-ICP-mass spectrometry (MC-ICPMS). The mass spectrometric interferences on Fe isotopes (e.g., 56ArO+ and 57ArOH+) were successfully minimized by a dry plasma condition achieved by a desolvating nebulizer sample-introduction technique. In order to eliminate possible variations in the measured isotopic ratios due to non-mass spectrometric interferences, Fe was separated from remaining organic compounds and major co-existing elements using an ion chromatographic technique. The resulting precisions of the 56Fe/54Fe and 57Fe/54Fe ratio measurements were 0.12 per thousand and 0.20 per thousand, respectively, which were high enough to detect the isotopic variation of Fe in nature. For an interlaboratory comparison, all of the Fe isotopic ratio data were normalized by the ratios for the IRMM-014 international isotopic standard. A series of 12 RBC samples were collected from one person through monthly-based sampling over a period of one year. These were analyzed to test possible seasonal changes in the 56Fe/54Fe and 57Fe/54Fe ratios. Moreover, in order to test possible variations in the 56Fe/54Fe and 57Fe/54Fe ratios among different people, RBC samples were collected from five volunteers (four males and one female). The 56Fe/54Fe and 57Fe/54Fe ratios for a series of 12 RBC samples collected over a one-year period show 3.06 per thousand and 4.51 per thousand lower than the values of IRMM-014, and no significant seasonal change could be found in the ratios. The lack in seasonal changes in the Fe isotopic ratios could be explained by a small contribution of the daily net-intake of Fe (1 - 2 mg/day) onto the total amount of Fe in the human body (2 - 4 g). The 56Fe/54Fe and 57Fe/54Fe ratios for RBC samples collected from four male samples did not vary measurably, whereas the Fe isotopic ratios for a female RBC were 0.3 per thousand/amu heavier than the mean value of four male samples. This difference in Fe isotopes among the individuals can be the result of a difference in uptake efficiency of the Fe through a dietary process from the digestive tract. The data obtained here demonstrate that the isotopic ratios of trace metals can provide new information about metabolic efficiencies of the metallic elements.  相似文献   

19.
通过简单溶剂热法制备了一种新型复合光催化剂BiVO_4/M IL-53(Fe);运用XRD、SEM/EDS、FT-IR、N_2吸附-脱附和UV-vis DRS等手段对其进行表征,并对其光催化降解RhB活性进行了研究,提出了相应的光催化降解RhB的可能机理。结果表明,相较于单一BiVO_4材料,复合催化剂的比表面积增大,且其光催化效率相较于纯BiVO_4和MIL-53(Fe)也有了较大的提高;其中,BF-2复合材料的光催化活性最高,分别约为纯MIL-53 (Fe)和BiVO_4的5. 2倍和8. 1倍。同时,BiVO_4/MIL-53(Fe)复合光催化剂经过四次循环实验后,仍能保持较稳定的光催化活性和结构。  相似文献   

20.
对常用61种中药作微量元素检测.发现补血滋肾类药铁含量丰富,而健脾益气类药铁和锌含量均高.制备脾虚模型小鼠以贫血冲剂喂养一周及二周,分别检测其全血中铁、锌、钙含量.发现喂养一周.脾虚组与对照组全血铁,锌.钙含员变化不大(P>0.05),而喂养二周,脾成组全血铁、锌、钙含量明显高于对照组(P<0.05)。  相似文献   

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