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131.
根据单糖与邻甲苯胺加成缩合反应的显色特征,采用偏最小二乘法(PLS)辅助分光光度法对吸收光谱重叠较严重、加和性欠佳的葡萄糖、果糖和木糖三组分的模拟混合试样进行分析,对同时测定的条件进行了优化,建立了单糖多组分体系同时定量分析的多元校正方法,并用此方法对蜂蜜样品中上述单糖组分的含量进行了测定.时模拟混合试样,回收率分别为...  相似文献   
132.
毛细管电泳电化学发光法测定盐酸帕罗西汀的研究   总被引:1,自引:0,他引:1  
实验发现盐酸帕罗西汀能增强钌联吡啶的电化学发光信号,据此建立了一种盐酸帕罗西汀的毛细管电泳-电化学发光测定新方法。在实验中,分别对毛细管电泳分离条件和电化学发光检测条件进行了优化。在优化的实验条件下,盐酸帕罗西汀检出限为3.45×10^-8g/mL(S/N=3),线性范围为3.0×10^-7-1.0×10^-4g/mL。通过对1.0×10^-5g/mL的盐酸帕罗西汀进行11次平行测定,峰高的RSD为2.5%。已用于盐酸帕罗西汀片剂的测定。  相似文献   
133.
为建立用电感耦合等离子体光谱法测定维药阿里红中微量元素及含量的方法,用硝酸-高氯酸进行消解,电感耦合等离子体原子发射光谱法(ICP-AES)同时测定了维药阿里红样品中Al、B、Ba、Ca、Co、Cr、Li、Mg、Mn、Cu、Fe、Ni、P、Sr、Ti、V、Zn等多种微量元素。结果表明,维药阿里红中含有比较丰富的Ca、Mg元素。ICP-AES法测定简单,快速,灵敏度高,准确,其相对标准偏差为0.36%~2.52%,回收率为95.8%~101.3%,且多元素同时测定,适用于维药阿里红中微量元素的测定。  相似文献   
134.
Beta-blockers are antihypertensive drugs and can be abused by athletes in some sport competitions; it is therefore necessary to monitor beta-blocker levels in biological samples. In addition, beta-blocker levels in environmental samples need to be monitored to determine whether there are contaminants from the activities of the pharmaceutical industry. Several extraction methods have been developed to separate beta-blocker drugs in a sample, one of which is molecularly imprinted polymer solid-phase extraction (MIP-SPE). MIPs have some advantages, including good selectivity, high affinity, ease of synthesis, and low cost. This review provides an overview of the polymerization methods for synthesizing MIPs of beta-blocker groups. The methods that are still widely used to synthesize MIPs for beta-blockers are the bulk polymerization method and the precipitation polymerization method. MIPs for beta-blockers still need further development, especially since many types of beta-blockers have not been used as templates in the MIP synthesis process and modification of the MIP sorbent is required, to obtain high throughput analysis.  相似文献   
135.
As a promising source of biologically active substances, the Artemisia species from Kazakhstan have not been investigated efficiently. Considering the rich history, medicinal values, and availability of the Artemisia plants, systematic investigations of two Artemisia species growing in the East Kazakhstan region were conducted. In this study, one new germacrane-type sesquiterpene lactone (11), together with 10 known sesquiterpenes and its dimer, were characterized from A. nitrosa Weber. Additionally, one new chromene derivative (1’) with another 12 known compounds, including coumarins, sesquiterpene diketones, phenyl propanoids, polyacetylenics, dihydroxycinnamic acid derivatives, fatty acids, naphthalene derivatives, flavones, and caffeic acid derivatives were isolated from A. marschalliana Spreng. All compounds were isolated and identified for the first time from these two Artemisia species. The structures of new compounds (11, 1’) were established by using UV, TOFMS, LC–MS, 1D and 2D NMR spectroscopic analyses. The cytotoxicity of all isolated compounds was evaluated. As a result, all compounds did not show significant inhibition against HL-60 and A-549 cell lines. The sesquiterpenoids isolated from A. nitrosa were tested for their inhibitory activity against the LPS-induced NO release from the RAW624.7 cells, and neither of them exhibited significant activity.  相似文献   
136.
探讨核磁共振氢谱结合模式识别方法应用于异常黑胆质糖尿病患者的尿液代谢组研究可行性。对32 例异常黑胆质糖尿病患者和29 例健康人尿液进行核磁共振氢谱检测,采用主成分分析(principal component analysis, PCA)、偏最小二乘法判别分析(partial least squares dis-criminant analysis, PLS-DA)、正交偏最小二乘法判别分析(orthogonal to partial least squares discriminant analysis,OPLS-DA)进行模式识别分析,比较3种模式识别方法的判别能力。运用3种模式识别均可以对2组数据进行有效的区分,但OPLS-DA较PCA、P[1]LS-DA更加有效,不仅提高了模式识别方法的判断能力,可以清楚的判断两组中有差异的代谢物。基于核磁共振氢谱结合模式识别分析方法可以为异常黑胆质糖尿病代谢标志物的寻找提供理论依据。OPLS-DA的模式识别方法较其它2种方法更具优势,在揭示维医理论本质上有着广阔的应用前景。  相似文献   
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