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1.
本文用AR-CM-MIC阳离子测定系统及Fura-2荧光技术,研究了研磨后表面存在自由基的α-石英,和离体肺泡巨噬细胞作用后细胞内游离Ca^2^+浓度([Ca^2^+)i)和游离Mg^2^+浓度([Mg^2^+]i的关系。发现在含Ca^2^+和Mg^2^+的介质中,α-石英表面自由基越多,[Ca^2^+]i和[Mg^2^+]i升高越大;在无Ca^2^+和Mg^2^+的介质中,新研磨的α-石英能引起  相似文献   

2.
本系统地研究了硫代苹果在络合滴定中的掩蔽性能,发现它在pH1.5~10可作为Sn^4+、Sb^3+、Tb^3+、Bi^3+、Cu^2+、Hg^2+和Ag^+等的掩蔽剂(在pH2~3.5还可掩蔽Fe^3+)。掩蔽上述离子后,可在pH2.5~3用Th^4+回滴EDTA,在pH5~6用EDTA滴定Zn^2+或Yb^3+等,或在pH10用EDTA滴定Mg^2+、Ca^2+、Mg^2++Ca^2+和Mn^  相似文献   

3.
本文研究了不同形态二氧化硅和硅酸盐对细胞内游离Ca^2+浓度[Ca^2+]i)及游离Mg^2+浓度[Mg^2+]i的影响。结果表明:硅溶胶,聚硅酸,不同硅原子数的固态多酸盐及固态二氧化硅都能使[Ca^2+]i和[Mg^2+]i升高。  相似文献   

4.
笼形聚氨肟树脂的研究:碱处理对吸附性能的影响   总被引:3,自引:1,他引:3  
研究碱处理的笼形聚氨肟树脂(BCAO)对二价金属离子的吸附行为。吸附结果若生成2:1配的,得Mg^2+,Ca^2+,Ba^2+,Mn^2+,Co^2+,Ni^2+,Zn^2+,Cd^2+,Pb^2+,Cu^2+离子的吸附效率分别是27.1、29.2、30.4、29.0、27.1、30.8、45.0、39.8、60.3、62.1%,Hg^2+离子的吸附效率高达105%,表明在吸附过程中同时生成2:1  相似文献   

5.
林君  李彬 《中国稀土学报》1993,11(4):307-310
在紫外光激发下,Eu^3+和Bi^3+在Me2Y8(SiO4)6O2基质(Me=Mg,Zn,Ca,Sr)中分别发射红光(^5D0-^7F2)和蓝光(^3P1-^1S0).Eu^3+发光的红橙比随着激发波长和Me^2+的不同而变化。荧光拉曼光谱表明,Eu^3+在四种基质中同时占据了4f格位和6h格位。依据Bi^3+发光的Stokes位移推断,当Me=Ca,Zn时,Bi^3+主要占据4f格位,而当Me  相似文献   

6.
本文用AR-CM-MIC阳离子测定系统及Fura-2荧光技术,研究了研磨后表面存在自由基的α-石英,和离体肺泡巨噬细胞作用后细胞内游离Ca2+浓度([Ca2+])和游离Mg2+浓度([Mg2+]i)的关系.发现在含Ca2+和Mg2+的介质中,α-石英表面自由基越多,[Ca2+]i和[Mg2+]i升高越大;在无Ca2+和Mg2+的介质中,新研磨的α-石英能引起[Ca2+]i和[Mg2+]i升高.Ca2+和Mg2+的升高可能部分由于细胞内结合钙和结合镁的释放.  相似文献   

7.
水溶液中四氮杂四乙酸大环与金属离子络合物的稳定性   总被引:2,自引:0,他引:2  
毕建洪 《分析化学》1995,23(7):809-812
本文采用pH电位滴定技术和计算机拟合,获得在20,25,30和40℃,0.5mol/L KCl水溶液中H4L(5,12-二苯基-7,14-二甲基-1,4,8,11-四氮杂环十四烷-四乙酸)的分步加质子常数及反应热焓值。又在40℃条件下测定了H4L与Cu^2+,Ni^2+,Co^2+,Zn^2+,Mn^2+,Cd^2+,Mg^2+,Ca^2+,Sr^2+,Ba^2+络合物的稳定常数,并对结果进行了讨  相似文献   

8.
笼形聚偕氨肟树脂的研究:酸处理树脂的吸附性能   总被引:5,自引:3,他引:5  
笼形聚偕氨肟树脂(CAO)经盐酸处理垢,伯胺基转变成胺盐。酸处理笼形聚偕氨肟树脂(ACAO)对Mg^2+,Ca^2+,Ba^2+,Mn^2+,Co^2+,Ni^2+离子不吸附;对Zn^2+,Cd^2+,Cu^2+,Pb^2+离子的吸附效率在20%以下,但对Hg^2+离子的吸附效率则高达71.2%;对一些金属络阴离子的吸附效率顺序是Fe(CN)^2-6>Cr2O^2-7>MoO^2-4>PtCl^2  相似文献   

9.
以咪唑为背景电解质,以α-羟基异丁酸和18-冠醚-6为络合剂,采用毛细管离子电泳间接紫外法,研究了发样中痕量NH4^+、K^+、Ca^+、Mg^2+分离与测定的方法。通过向缓冲液中加入甲醇,使Ca^2+、Na^+迁移顺序发生反转,有利于在Ca^2+的浓度较高时少量Na^+的测定。采用电堆集富集技术,各离子的检测限达1×10^-7mol/L。以Li^+作为内标,采用标准加入法对地样中的痕量阳离子进行  相似文献   

10.
镧和钙对人红细胞膜的作用   总被引:11,自引:1,他引:11  
采用荧光偏振,自旋标记电子顺磁共振波谱和激光拉曼光谱等技术研究了镧和钙对人红细胞膜结构和功能的影响。结果表明,低浓度的La^3+(0.5umol/L)对(Na^++K^+)-ATP酶,Mg^2+-ATP酶有轻微的激活作用,随着浓度的增大,则明显抑制酶的活性。La^2+可降低红细胞 的膜脂充动性,使膜蛋白酰胺1’-a螺旋振动强度减弱;Ca^2+对膜脂流动性和膜蛋白酰胺1’-a螺旋的影响比La^3+小  相似文献   

11.
目的探讨乳腺癌患者化疗效果对血清中钙(Ca)、磷(P)、镁(Mg)以及锌(Zn)含量的影响。方法选取普宁市人民医院进行化疗的乳腺癌患者80例作为化疗组,观察患者化疗前后血清中Ca、P、Mg以及Zn的水平变化,另选80例健康女性作为健康人组,检测其血清Ca、P、Mg、Zn水平,并进行对比分析。结果化疗组Ca、Mg含量明显低于健康人组(P0.05),Zn含量明显高于健康人组(P0.05),P含量与健康人组相比无统计学意义(P0.05);化疗后Ca、Mg含量显著高于化疗前(P0.05),Zn含量显著低于化疗前(P0.05),P含量略低于化疗前(P0.05)。结论血清Ca、P、Mg、Zn含量随着临床治疗效果所变化,可作为检测化疗效果的有效反应因子,在疗效判定方面具有一定的参考价值。  相似文献   

12.
Erythrocyte membranes prepared by three different procedures showed (Mg2+ + Ca2+)-ATPase activities differing in specific activity and in affinity for Ca2+. The (Mg2+ + Ca2+)-ATPase activity of the three preparations was stimulated to different extents by a Ca2+-dependent protein activator isolated from hemolysates. The Ca2+ affinity of the two most active preparations was decreased as the ATP concentration in the assay medium was increased. Lowering the ATP concentration from 2 mM to 2-200 microM or lowering the Mg:ATP ratio to less than one shifted the (Mg2+ + Ca2+)-ATPase activity in stepwise hemolysis membranes from mixed "high" and "low" affinity to a single high Ca2+ affinity. Membranes from which soluble proteins were extracted by EDTA (0.1 mM) in low ionic strength, or membranes prepared by the EDTA (1-10 mM) procedure, did not undergo the shift in the Ca2+ affinity with changes in ATP and MgCl2 concentrations. The EDTA-wash membranes were only weakly activated by the protein activator. It is suggested that the differences in properties of the (Mg2+ + Ca2+)-ATPase prepared by these three procedures reflect differences determined in part by the degree of association of the membrane with a soluble protein activator and changes in the state of the enzyme to a less activatable form.  相似文献   

13.
营养不良婴幼儿红细胞内外锌、铜、钙、镁变化及其意义   总被引:1,自引:1,他引:0  
对18例营养不良婴幼儿血浆及红细胞内的锌,铜,钙,镁元素含量进行了测定,并与15例健康婴幼儿进行对照。结果表明,营养不良患儿血浆中锌,钙降低,与健康组相比有显著性差异(P〈0.01);营养不良患儿红细胞内锌,镁降低,钙升高,与健康组相比均有显著性差异(P〈0.01)。因此,营养不良婴幼儿红细胞内外锌,钙,镁的变化应引起重视。  相似文献   

14.
Ghost membranes prepared from human erythrocytes exhibit 2 distinct (Ca + Mg)-ATPase1 activities (Quist and Roufogalis, Arch Biochem Biophys 168:240, 1975). (Ca + Mg)-ATPase activity dependent on a water soluble protein fraction is selectively lost from ghost membranes during preparation of vesicles under low ionic strength, slightly alkaline conditions. In this study, the Ca2+ dependence of the remaining membrane bound (Ca + Mg)-ATPase activity and ATP-dependent Ca uptake in vesicles were compared. The Ca2+ activation curves for (Ca + Mg)-ATPase activity and Ca uptake into vesicles were parallel over a Ca2+ range of 0.3-330 micrometer, and both curves have 2 apparent KA values for Ca2+ of 0.45 and 100 micrometer. Addition of a concentrated soluble protein fraction containing predominantly spectrin to the vesicles increased (Ca + Mg)-ATPase activity over twofold but did not affect the rate of Ca uptake. These findings suggest that the (Ca + Mg)-ATPase activity remaining in vesicles after extraction of the water soluble proteins is associated with the Ca pump whereas (Ca + Mg)-ATPase activity dependent on the soluble protein fraction is associated with some other function.  相似文献   

15.
An Mg2+-dependent low ATPase activity can be detected in erythrocyte "white membranes," in addition to that of the well known (Ca2+ + Mg2+)-ATPase. The thiol oxidizing agent diamide affects both activities. The oxidation of neighboring thiols seems to leave the mechanism of the (Ca2+ + Mg2+)-ATPase amplification system evoked by Ca2+ largely unaffected. The perturbation caused by diamide in the membranes seems to affect primarily a step of the ATP hydrolysis mechanism that is common to both ATPase activities. The effectiveness of diamide seems to be the same when either Ca2+ and Mg2+, or Mg2+ alone are present during the reagent action. Reduction of disulfide bonds by DTE after diamide treatment restores the (Ca2+ + Mg2+)-ATPase activity but is unable to take the Mg2+-ATPase activity back to the original level. The hypothesis is discussed that the redox state of one (or more than one) couple of --SH close to each other and possibly connected to the active site, may be an important factor in optimizing the efficiency of Ca action on the (Ca2+ + Mg2+)-ATPase.  相似文献   

16.
An modified laminar crystal sodium silicate(Al-SKS-6)was synthesized by spray drying and high temperature crystallization using sodium silicate as silicon source,Al atom as inorganic source and hexadecyltrimethy ammomum bromide(CTMAB)as the structure template.The hydrothermal stability of product was at least 1 h.The synthesized material was characterized by XRD and SEM.The results indicated that shape and intensity of XRD diffraction peak at 20 took changes.but raw material δ phase crystal form kept unchanged.and assured high Ca2+ and Mg2+ binding capacity of the products.The Ca2+ and Mg2+ binding capacity of product is up to 380 mg Ca/g and 410mg Mg/g respectively.It was found that the hole of product became smaller and appeared rod structure based on SEM. The hydrothermal stability was increased due to the pillaring of A1 atom.  相似文献   

17.
急性脑血管病患者血清元素的测定   总被引:3,自引:1,他引:3  
采用高频等离子体发射光谱法测定了34例脑梗塞、33例脑出血和对照组27人血清锌、铜、锰、铬、镁、钼、锶、铁、钛、钡、镉和钙共12种元素的含量。结果显示脑梗塞和脑出血组血清锌和锌/铜比值显著高于对照组;锰和钼含量仅在脑梗塞组明显增高,锶仅在脑出血组显著增高,而其它几种元素疾病组与对照组无显著性差异。伴有高血糖、高血脂和高血压的病人,其血铬含量显著降低,表明锌、锌/铜比值、锰、钼、锶、铬元素与急性脑血  相似文献   

18.
头发六种元素含量变化与Graves病关系的研究   总被引:2,自引:0,他引:2  
为探讨Graves病患者头发6种元素含量变化与临床的关系,检测并比较了32例患者头发中微量元素Zn、Cu、Fe、Mn和常量元素Ca、Mg含量。提示Graves病人某些临床表现可能与体内元素异常有关。  相似文献   

19.
聚合物分散剂对氟虫脲水悬浮剂分散稳定性的影响   总被引:4,自引:0,他引:4  
通过测定药物颗粒界面Zeta电位和平均粒径, 研究了聚合物分散剂苯乙烯磺酸聚合物钠盐(GY-D08)用量、pH和盐离子对氟虫脲水悬浮剂分散稳定性的影响, 研究结果表明, 分散剂GY-D08的加入量与水悬浮剂分散效果密切相关, 制备质量分数为5%氟虫脲水悬浮剂的GY-D08最佳用量为2%, GY-D08用量过多或过少都会使分散效果下降; pH影响分散剂GY-D08在水中的电离能力, 当pH=9时, GY-D08分子完全电离, 能为颗粒提供较大的静电位阻, 水悬浮剂分散稳定性最好; Mg2+或Ca2+压缩颗粒界面的双电层, 降低Zeta电位, 使颗粒因带电量减少而聚结, 导致水悬浮剂分散稳定性变差, 且Mg2+或Ca2+浓度愈大, 其分散稳定性愈差; 当离子浓度相同时, Ca2+压缩双电层的能力比Mg2+强, 添加Ca2+后的水悬浮剂的分散稳定性更差.  相似文献   

20.
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   

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