Optical detection of triggered atherosclerotic plaque disruption by fluorescence emission analysis

Fluorescence emission analysis (FEA) has proven to be very sensitive for the detection of elastin, collagen and lipids, which are recognized as the major sources of autofluorescence in vascular tissues. FEA has also been reported to detect venous thromboemboli. In this paper we have tested the hypothesis that FEA can reproducibly detect in vivo and in vitro triggered plaque disruption and thrombosis in a rabbit model. Fluorescence emission (FE) spectra, recorded in vivo, detected Russell's viper venom (RVV)-induced transformation of atherosclerotic plaque. FE intensity at 410-490 nm 4 weeks after angioplasty was significantly lower (P < 0.0033 by analysis of variance) in RVV-treated rabbits when compared to control animals with stable plaque. FE spectral profile analyses also demonstrated a significant change in curve shape as demonstrated by polynomial regression analysis (R2 from 0.980 to 0.997). We have also demonstrated an excellent correlation between changes in FE intensity and the structural characteristics detected at different stages of "unstable atherosclerotic plaque" development using multiple regression analysis (R2 = 0.989). Thus, FEA applied in vivo is a sensitive and highly informative diagnostic technique for detection of triggered atherosclerotic plaque disruption and related structural changes, associated with plaque transformation, in a rabbit model.     

交联聚苯乙烯强－弱碱树脂的合成及脱色性能研究

交联聚苯乙烯氯甲基化后，分别与甲胺（或二甲胺）、三甲胺（或α－甲基吡啶、二甲基乙醇胺）混合胺化试剂进行亲核取代反应，合成了一系列同时带有强－弱碱功能基的交联聚苯乙烯树脂，并表征了这些树脂的结构，测定了树脂对甜菊甙的脱色性能，结果表明，这些树脂功能基碱性适中，脱色容量较高，甜菊甙损失较少，再生效率高。     

钇对2618合金组织及性能的影响

采用X射线，光学显微镜及扫描电镜等手段研究了2618合金中的组织与相结构，并研究了元素钆在2618合金中的存在形式及其对合金力学性能的影响。结果表明，微量钆元素在铝合金中是以化合物形式存在的；钆对合金中的铸态组织及Al9FeNi仃形态没有影响。由于微量钆的加入，降低了铜与镁在2618合金中的固溶量，减少了时效析出相A2CuMg数量，从而降低2618合金的室温强度帮在250℃的高温瞬时强度；但由于微量钆减少了铜与镁在2618合金中的扩散速度，延缓了时效机的粗化，并由于第二相数量的增多，因此提高了2618合金在250℃经100h高温热暴露后的高温瞬时强度。     

Separation and determination of podophyllum lignans by micellar electrokinetic chromatography

A micellar electrokinetic chromatography method was established for the quantitative analysis of seven podophyllum lignans in Podophyllum emodi Wall. var. chinesis sprague. The optimum buffer system was 10 mM NaH2PO4-5 mM borate-100 mM sodium dodecylsulfate-30% isopropanol (pH 7.20). Voltage was 18 kV and detection at 214 nm. The second derivative chromatogram was used to determine a low-content component and those not fully separated from adjacent ones. The RSD values of migration times and peak areas were <2.2 and <5.5%, respectively. The effects of several CE parameters on the resolutions were studied systematically.     

Use of p-dimethylaminobenzalhyde as a colored reagent for determination of procaine hydrochloride by spectrophotometry

Spectrophotometric determination of procaine hydrochloride is described. The procaine hydrochloride reacts with p-dimethylaminobenzalhyde in glacial acetic acid to form an Schiff base which is a yellow compound, and its maximum absorption wavelength is at 455nm, ₄₅₅=3.46×10⁴. The absorbance for procaine hydrochloride from 0.2 to 15 μg ml⁻¹ obeys Beer's law. The linear regression equation of the calibration graph is C=5.866A−0.02, with a linear regression correlative coefficient is 0.9994 and relative standard deviation (RSD) of 1.7%; the detection limit is 0.1 μg ml⁻¹; recovery is from 92.0 to 110.0%. Effects of reaction medium, temperature, gentamycin, beneylpenicillin, kanamycin, streptomycin, foreign ions, and stand for time on the determination of procaine hydrochloride have been examined. The results obtained by this method agreed with those by the official method (dead-stop titration). This method is rapid and simple, and can be used for the determination of procaine hydrochloride in injection solution of procaine hydrochloride.     

C1/Ag(111)体系研究 Ⅳ.氯吸附对甲醇吸附氧化的影响

运用HREELS技术对甲醇在预吸附氯的Ag(111)表面上的吸附氧化行为进行了较细致的研究.结果证明Cl对甲醇氧化的影响缘于它在Ag(111)上的吸附所引起的表面结构的改变进而改变表面氧吸附物种,从而使得甲醇氧化的中间产物发生变化.实验结果说明甲醇在Ag(111)和低暴露量氯吸附的Ag(111)表面上的氧化行为是相似的,检测到了中间产物Ⅰ和Ⅲ;在高暴露量氯吸附的Ag(111)上甲醇氧化时则产生中间产物Ⅰ、Ⅳ和甲醛物种.对上述不同的甲醇氧化行为作了分析,并指出了以前人们在考察甲醇氧化机理时只考虑原子氧作用的片面性.     

混合型杂多化合物Mx[GaW9M3O40]·nH2O的合成和性质

本文报道了M_x[GaW₉M₃^′O₄₀]nH₂O(M′=Mo,V,Ti,Fe(Ⅲ),Co(Ⅱ),Ni(Ⅱ),Mn(Ⅱ);M=k,Na,Gua,Me₄N,Et₄N,Bu₄N)的合成。通过元素分析,阴离子电荷的确定,极谱、IR及UV光谱、可见光谱、ESR、磁化率测定对其进行了表征。并研究了它们在水溶液中对酸碱的稳定性     

Localized molecular orbitals and the problem of quasi-aromaticity in trinuclear molybdenum cluster compounds with cores of the type [MO3(μ3-X)(μ-Y)3] (X, Y = O, S, n = 4; X = O, Y = Cl, n = 5)

Calculations of localized molecular orbitals (LMO) and their energy levels for the cluster cores [MO₃O₄]⁴⁺, [MO₃SO₃]⁴⁺, [MO₃OS₃]⁴⁺, [Mo₃S₄]⁴⁺ and [MO₃OCl₃]⁵⁺ have been made by the use of energy-localized CNDO/2-LMO. The results of these LMO calculations show that the six-membered closed and continuous π-conjugated systems around the [MO₃Y₃] rings, each of which is formed from three synergically connected three-centered two-electron π bonds, is the most significant feature of the electronic structure for the quasi-aromatic clusters [Mo₃(μ₃-Y)(μ-X)₃]⁴⁺ (X, Y = O, S), and the size and electronegativity of the bridging Y atoms exhibit significant effects on the degree of quasi-aromaticity of these cluster compounds. For the non-aromatic reference cluster [Mo₃OCl₃]⁵⁺, the results of our calculations also show a bonding scheme with only one isolated π bond, thus leading to the loss of quasi-aromaticity; and meanwhile, there is a pair of extra electrons localized on the apical molybdenum atom of the Mo₃ triangle, thus with three Mo---Mo single bonds.     

提高普通低碳钢冷镦性能的工艺研究

本文分析比较了普通低碳Q195钢与冷镦钢生产工艺、性能组织等情况,对武钢目前生产的Q195钢进了取样冷镦试验,并进行了不同的控冷工艺轧制试验.提出在武钢目前炼钢生产条件下,采用适当的轧制工艺,完全可以用普通低碳Q195钢代替部分铆螺钢.