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121.
Jun Shi  Yiming Wang  Guoan Luo 《Chromatographia》2011,74(11-12):827-832
This work was designed to assess the holistic efficacy of concurrent treatment with huperzine A (HA) and ligustrazine phosphate (LP) in the animal model, and to interpret the metabonomics characteristics of the poly-therapy in treating Alzheimer??s disease (AD). Metabolic profiling of the brain was performed using ultra performance liquid chromatography coupled to time-of-flight mass spectroscopy (UPLC-TOF MS). Principal component analysis and partial least squares discriminant analysis were utilized to classify and reveal the differences among the control, model and treatment groups. Ten potential biomarkers have been finally gained. The metabonomic results revealed that the coadministration of HA and LP might slow down the progression of AD through synergistic therapeutic efficacies, exhibiting better effect on amnesia compared with the mono-drug therapy. Importantly, the UPLC-TOF MS-based metabonomic approach would be a useful technique for the diagnosis of AD, the discovery of metabolic biomarkers and the evaluation of the treatment effects.  相似文献   
122.
狭义相对论解决双生子佯谬之不可能   总被引:11,自引:1,他引:10  
详细地阐明了狭义相对论解决双生子佯谬之不可能,对一种很有影响的狭义相对论解进行了深入细致的分析  相似文献   
123.
从投资将导致地价增值的观点出发,建立了新建成改建公路沿线基准地价评估的分段指数递减的数学模型,采用“四三二一”法则建立了公路两侧不同纵深土地的基准地价评估的数学模型,并应用于宁波市江北区公路的基准地价评估,取得了较为满意的效果。  相似文献   
124.
一类实轴上向量边值问题与矩阵函数分解   总被引:1,自引:0,他引:1  
通过引进奇异积分算子和矩阵函数分解的概念,研究了实轴上一类向量Riemann边值问题与奇异积分算子、矩阵函数分解之间的关系.在实轴上向量边值问题的系数矩阵满足某种分解条件下,给出了其可解的充要条件和解的封闭形式及与奇异积分算子之间的等价关系,并给出了一类矩阵函数的亚纯分解的显形式.  相似文献   
125.
粗糙表面测量轮廓的分形插值模拟   总被引:3,自引:1,他引:3  
引入粗糙表面的分形插值理论,提出用分形插值函数模拟粗糙表面轮廓的方法。并以车削,磨削及磨损表面为研究对象,对粗糙表面进行了分形插值模拟,系统地研究了影响其模拟模拟效果的因素和规律。发现可以采用分形插值理论来模拟或表征具有分形特征的粗糙表面。  相似文献   
126.
Nine ent-kaurene diterpenoids, leukamenin E, glaucocalyxin A, wangzaozi A, epinodisinol, epinodosin, rabdosin B, rabdosinate, lasiokaurin and oridonin, were separated from Isodon racemosa (Hemsl) Hara and Isodon japonica (Burm.f) Hara var. galaucocalyx (maxin). The protection against DNA damage induced by hydrogen peroxide in human peripheral blood mononuclear cells (PBMCs) and inhibition of lipid peroxidation in rat liver microsome were studied with comet assay and thiobarbituric acid reactive substances determination. All nine diterpenoids showed concentration-dependent protection in DNA damage in human PBMCs induced by 50 μM H2O2. The effects were similar and weaker than quercetin. The inhibitions of lipid peroxidation were obviously difference. Rabdosin B and oridonin were the strongest inhibitors, followed by lasiokaurin and wangzaozin A. Rabdosinate was the weakest and others were medium. The structure-activity relationship is discussed.  相似文献   
127.
首次对房地产价格评估的投资法进行反向运用,对因投资而产生的二种截然不同的纯收益,其中之一是已知的,而另一是未知的,当投资回报率给定时,导出一个投资回报率模型。作为应用,得到开发区基准地价评估的投资回报率模型,从而得到一个开发区已开发区域内国家所能接受的最低整体地价水平,为开发区的基准地价确定奠定基础。最后通过实例说明.该模型在开发区基准地价评估过程中所起的主导的不可替代的作用。  相似文献   
128.
Shi  Jun  Wang  Yiming  Luo  Guoan 《Chromatographia》2011,74(11):827-832

This work was designed to assess the holistic efficacy of concurrent treatment with huperzine A (HA) and ligustrazine phosphate (LP) in the animal model, and to interpret the metabonomics characteristics of the poly-therapy in treating Alzheimer’s disease (AD). Metabolic profiling of the brain was performed using ultra performance liquid chromatography coupled to time-of-flight mass spectroscopy (UPLC-TOF MS). Principal component analysis and partial least squares discriminant analysis were utilized to classify and reveal the differences among the control, model and treatment groups. Ten potential biomarkers have been finally gained. The metabonomic results revealed that the coadministration of HA and LP might slow down the progression of AD through synergistic therapeutic efficacies, exhibiting better effect on amnesia compared with the mono-drug therapy. Importantly, the UPLC-TOF MS-based metabonomic approach would be a useful technique for the diagnosis of AD, the discovery of metabolic biomarkers and the evaluation of the treatment effects.

  相似文献   
129.
The reaction kinetics between acetic acid and Ag2+ in nitric acid medium is studied by spectrophotometry. The effects of concentrations of acetic acid (HAc), H+, NO?3, and temperature on the reaction are investigated. The rate equation has been determined to be –dc(Ag2+)/dt = kc(Ag2+)c(HAc)c?1(H+), where k = (610 ± 15) (mol/L)?1 min?1 with an activation energy of about (48. 8 ± 3.5) kJ mol?1 when the reaction temperature is 25°C and the ionic strength is 4.0 mol L?1. The reduction rate of Ag2+ increases with the increase in HAc concentration and/or temperature and the decrease in HNO3 concentration. However, the effect of NO?3 concentrations within 0.5–2.5 mol L?1 on the reaction rate is negligible. © 2012 Wiley Periodicals, Inc. Int J Chem Kinet 45: 47–51, 2013  相似文献   
130.
本文运用实变复值函数积分计算方法研究了一类不定积分的新解法,给出了它的显式计算公式.该方法不仅推广了许多近期文献的研究结果,而且具有计算简洁的优点.  相似文献   
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