薄层-紫外法测定混合物中叠氮化合物的含量

采用薄层－紫外分光光度法测定了混合物中叠氮化合物4－叠氮基－2,3,5,6－四氟苯甲酸（AFBA）的含量。工作曲线在2.69-16.58μg/mL范围内呈线性关系,两次测定的回收率分别为99.8%和100.2%。     

TCP复合BMP-2促骨再生作用的研究

目的探讨TCP复合BMP-2促骨再生作用,为临床BMP-2的应用提供参考。方法利用16只雄性Wistar大鼠建立大鼠颅盖骨临界骨缺损模型,制备TCP支架及TCP复合BMP-2支架,并分别植入到动物模型的骨缺损处,术后12周测定新生骨形成面积并进行比较。结果所有实验动物无一死亡,全部存活,伤口愈合良好,未见感染症状。术后12周,TCP复合BMP-2组骨密度为(475.32±19.20)mg/cm2,而单纯TCP组明骨密度为(124.25±13.64)mg/cm2,两组比较TCP复合BMP-2组的成骨效果明显较TCP组为佳,差异显著有统计学意义(P0.05)。结论所制备的TCP复合BMP-2能改进单纯TCP的促成骨效果,具有良好的成骨活性,促进骨修复。     

图中存在[a,b]-因子的一个充分条件

设G是一简单连通图,其联结数定义为b(G)=min{|NG(X)|/|X|:■≠X■V(G),N_G(X)≠V(G)}.文章通过图G的联结数刻画了其中存在[a,b]-因子的一个充分条件.     

Synthesis and Crystal Structure of 3,3'-Bis(5-(N-(4-hydroxylphenyl)imidomethyl)- pyrrol-2-yl)pentane·2CH_3OH

3,3'-Bis(5-(N-(4-hydroxylphenyl)imidomethyl)pyrrol-2-yl)pentane 1 has been synthesized and characterized. The crystal of its methanol complex, 1·(CH3OH)2, belongs to the orthorhombic system, space group Pccn with a = 18.094(2), b = 11.6890(16), c = 13.3629(19) , V = 2826.3(7) 3, Z = 8, C14.5H18N2O2, Mr = 252.31, Dc = 1.186 g/cm3, F(000) = 1080 and μ(MoKα) = 0.080 mm-1. The final R = 0.0662 and wR = 0.1801 for 1908 observed reflections with I 2σ(I), and R = 0.0800 and wR = 0.1948 for all reflections. In the solid state, bridged by included methanol molecules, the molecules of compound 1 form interpenetrated grid structure through N–H···O and O–H···O hydrogen bonds.     

[a,b]-因子包含给定圈的充分条件

设G是一个图且a,b是非负整数,a≤b.图G的一个[a,b]-因子是图G的一个支撑子图H且满足对所有的x∈V(G),a≤dH(x)≤b都成立.给出了图中[a,b]-因子包含给定圈的一个充分条件.     

单圈图的离心连通度指标

设G=（V,E）是连通图.G的离心连通度指标定义为（？）~c（G）=∑_（x∈V）ec（x）deg（x）,其中ec（x）是x的离心率,deg（x）是x的度.我们得到了直径为d的单圈图的上下界     

一元二次方程的概念及解法的复习课

复习课是数学教学中一个非常重要的环节,教育圣人孔子在两千多年前就指出"温故而知新".但如何上好复习课,一直是每位数学教师感觉到比较困难的事情.因为,想要复习的知     

图的[a,b]-因子存在性的两个结果

设G是一个图,a,b是整数且满足0≤a≤b.如果存在G的一个支撑子图F,使对任意的x∈V(G)有a≤dF(x)≤b,则称F是G的—个[a,b]-因子.本文给出图中具有特定性质的[a,b]-因子的两个充分条件.     

Synthesis,Structure and Spectra Properties of a Novel BOIMPY Compound

A bis-2-iminopyrrole compound(1) and its difluoroboron complex(2) were synthesized and characterized. The crystal of 2 is in the monoclinic system, P2_1/n space group with a = 21.5113(15), b = 6.3036(3), c = 21.5064(15) ?, V = 2826.3(7) ?~3, Z = 4, C_(26.5) H_(25) B_2 ClF_4 N_4 O, M_r = 548.57, D_c = 1.390 g/cm, F(000) = 1132 and μ(MoKα) = 1.787 mm~(-1). The final R = 0.0647 and wR = 0.1817 for 10346 observed reflections with I 2σ(I), and R = 0.0889 and wR = 0.1993 for all data. The molecules of complex 2 self-assemble through C–H×××F hydrogen bonds and form tubular structures which are filled by CH_2 Cl_2 molecules stabilized by C–H×××π interaction. The UV-Vis spectra of complex 2 show great bathochromic shift compared to that of compound 1 due to the difluoroboron complexing. Complex 2 shows fluorescence emission both in solid state and in solution, whereas compound 1 only exhibits fluorescence emission in solid state.     

TCP复合BMP-2诱导hMSCs成骨分化的协调机制研究

目的探讨TCP复合BMP-2诱导h MSCs成骨分化的协调机制。方法分别制备TCP支架及TCP复合BMP-2支架材料,自3名志愿者身上分离h MSCs进行传代扩增,取第3代细胞接种备好的支架材料,在复合后的第1、3、7天测量ALP的活性并进行比较。结果在复合后第1天,两组间ALP活性值比较无明显差异(P0.05);在复合后第3、7天两组间ALP活性值比较差异显著(P0.05);TCP与细胞培养组1、3、7天的ALP活性值差异不显著,无统计学意义(P0.05);TCP复合BMP-2与细胞培养组的1、3、7天的ALP活性值随着培养时间的延长,逐渐升高。结论 BMP-2能协调TCP促进h MSCs的分化效应,基因治疗可能为骨骼疾病提供一种新的治疗途径。