8位取代吡咯甲川-BF2化合物的光物理行为

Six novel pyrromethene BF2 complexes,of which five compounds have not been reported,were synthesized and characterized.Their relationships between st ructure and photophysical behavior were studied with the aid of fluorescence and triplet state absorption spectra.The results indicate that,compared to 8 alkyl pyrromethene BF2 complexes,the compounds containing 8 aryl exhibit high fluore scence quantum yield and rather low triplet state absorption.     

光聚合水凝胶及其在组织工程中的应用

水凝胶是一种亲水性聚合物网络,可以溶胀大量水,其物理性质接近软组织.光聚合与传统的聚合方法相比,具有反应速率快、反应条件缓和、反应放热低等特点.因此,光聚合水凝胶广泛应用于生物医学领域.本文介绍了光聚合水凝胶材料,并详细论述了光聚合水凝胶在药物释放体系、组织工程支架材料、细胞受控生长、细胞微囊化和可注射水凝胶等方面的应用.可以预见光聚合水凝胶作为生物材料在组织工程及再生医学领域中具有良好的应用前景.     

GC-MS法检验利多卡因代谢物单乙基甘氨酰二甲苯胺

近年来,大量研究表明,利多卡因的代谢物单乙基甘氨酰二甲苯胺(MEGX)的生成速率及含量变化与肝脏贮备功能密切相关,所以,MEGX试验(MEGX test)目前被广泛用于临床和药理学实验,评估肝移植时供肝的贮备功能,以及各种因素对肝脏生物转化功能的影响.测定60 min时的MEGX血药浓度比测定利多卡因更有临床意义.     

A COMPARISON OF DENATURATION AND INACTIVATION RATES OF CREATINE KINASE IN GUANIDINE SOLUTIONS

Both the denaturation, as followed by UV absorbance and fluorescence changes, and inac-tivation of creatine kinase in guanidine solutions have been found to be first order reactions.In 3 M guanidine, at 30℃, the inactivation rate constant was found to be 5.9 sec~(-1) and thedenaturation rate constant 1.9 sec~(-1). At lower guanidine concentrations, the inactivation rateconstants were only little affected whereas the denaturation rate constants decreased markedly,being of the order of 0.04 in 1 M and 0.004 in 0.5 M guanidine. The kinetics of the inactiva-tion reaction in 0.5 M guanidine was found to be in agreement with a combination of two firstorder reactions. The enzyme lost activity first by a fast reaction with a rate constant onlyslightly lower than the rate constant in 3 M guanidine followed by a slower reaction with a rateconstant of 0.003 sec~(-1). In 0.3 M guanidine, very little change in either UV absorbance or influorescence was observed, but, in sharp contrast, the enzyme lost considerable activity by a fastreaction and this was followed by a slower reaction of inactivation. Even after prolongeddenaturation in 0.5 and 0.3 M guanidine, residual activities of 3.4% and 30% remained res-pectively. The above results suggest a very fragile active site although dissociation of thedimer and reversible guanidine inhibition may also contribute to the initial rapid inactiva-tion. It is also to be noted that the multiphasic courses of inactivation at lower guanidineconcentrations seem to suggest the presence of partly active intermediates during denaturation.     

手性识别及氨基酸类手性固定相的研究进展

近年来, 手性识别更加凸现出极其重要的现实意义, 而作为分离手性分子应用的手性固定相自然引起了大家的关注．立足于国内外手性固定相的研究成果, 介绍了手性固定相及其分类, 并重点综述了基于氨基酸的手性固定相的发展及其制备方法. 同时, 简要介绍了作为手性固定相对不同异构体的识别机理.     

Synthesis and Crystal Structure of [NdCl_5(THF)]~(2-) [HO-4,6-di-~tBu-C_6H_2-2-CH_2{CH(~i PrNCHCHN)}]_2~ ·THF

The title complex 1·THF has been synthesized by the reaction of [HO-4,6-di-tBu- C6H2-2-CH2{CH(iPrNCHCHN)}]Cl with NdCl3 in a 2:1 molar ratio in THF, and characterized by single-crystal X-ray diffraction. It crystallizes in monoclinic, space group P21/c with a = 9.6501(14), b = 16.393(2), c = 36.745(6) , β = 97.444(4)o, V = 5763.7(15) 3, Mr = 1124.69, Z = 4, Dc = 1.296 g/cm3, μ(MoKα) = 1.175 mm-1, F(000) = 2348, the final R = 0.0729 and wR = 0.1762 for 8735 observed reflections with I > 2σ(I). Complex 1 consists of an anion [NdCl5(THF)]2- and two cations [HO-4,6-di-tBu-C6H2-2-CH2{CH(iPrNCHCHN)}]2 to form a layer structure by the interconnection of anions and cations via hydrogen bonding. The central metal Nd in the anionic unit is coordinated by five Cl atoms and one oxygen atom from solvated THF molecule assuming a distorted octahedral geometry.     

SURFACE OF GELATIN MODIFIED POLY(L-LACTIC ACID)FILM

In this paper, the surface structure of poly(L-lactic acid) (PLLA) film modified with gelatin was investigated. ThePLLA film specimens were treated directly with aqueous alkali solution to provide their surfaces with carboxyl groups, sothat these functional groups could become the reactive sites for gelatin immobilization. The functional groups of the PLLAfilms were identified by ATR-FTIR spectra and XPS spectra, the changes in surface morphology were observed by usingenvironmental scanning electron microscopy (ESEM), and the hydrophilicity of modified PLLA films was examined bywater contact angle measurement. Experimental results showed that the gelatin was immobilized with water-solublecarbodiimide (EDC) onto the PLLA film's surfaces, and the gelatin content on the polymer surface was related to carboxylicgroup formed in the controlled hydrolysis process. Rough surfaces caused by hydrolysis will predominantly favor the adhesion and growth of cell; and the hydrophilicity of these surfaces after the modification procedure is enhanced.     

催化不对称硅氧化反应研究进展

综述了催化不对称硅氢化反应的研究进展情况，重点介绍了最近十年来手性催 化剂配体的研究情况。     

再障头发、血清和骨髓组织钴、锂元素含量的变化

采用原子吸收光谱技术测定再障４３例患者头发、血清和骨髓组织的钴、锂元素含量，并与急性白血病２０例、缺铁性贫血１０例和正常人４４例作对照比较，再障头发、骨髓钴、锂和血清钴含量均低于正常人，Ｐ＜０．０５，而与急性白血病和缺铁性贫血之间，以及各种类型再障之间则无差异性．再障头发锂含量与血红蛋白、红细胞数呈负相关，Ｐ＜０．０５，说明再障确实存在着钴、锂元素代谢异常．     

氢化物发生—光度分析法连续测定砷锡

锗、砷、锡、锑等性质相近元素在用普通分光光度法测定时,存在着选择性差的问题,为实际分析及连续测定造成了困难。共价氢化物发生-银溶胶光度分析体系的建立和发展,基本解决了此类元素的选择性问题,也为同时或连续测定创造了条件。本文在原工作的基础上,借助于AsH_3和SnH_4在形成酸度上的差异,在高酸度(3.0mol/L HCI)溶液中使砷离子转变为AsH_3逸出分析后,再调节至微酸性(pH 4.5,CH_3COOH-CH_3COONa)产生SnH_4,而显色测定,