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The chemiluminescence (CL) intensities of various indole derivatives substituted with a glyoxylyl group at the 3-position and a hydroxyl group at the 5-position of the indole ring were compared upon the addition of H2O2 in alkaline media. The CL intensities of 3-indoleglyoxylyl chloride, 3-indoleglyoxylic acid, 5-hydroxyindole and 5-benzyloxyindole in CH3CN were 5.9-, 48-, 5.9- and 3.3-fold stronger than that of 3-methylindole. A lasting CL of 3-indoleglyoxylyl chloride was found. Under appropriate conditions, the CL emission reached a maximum within 10 min after the addition of H2O2 in the presence of NaOH, and the intensity was retained for 25 min. One of the final products via the CL reaction of 3-indoleglyoxylyl chloride was indole-3-carboxylic acid. 3-Indoleglyoxylyl chloride emitted light by decompositions via both dioxetane and dioxetanedione. An enhancement effect of beta-cyclodextrin and bovine serum albumin on the CL of 3-indoleglyoxylyl chloride was also found.  相似文献   
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Quantitative determination of ppb-order 10B was carried out in a small number of cultured tumor cells by particle tracks by the 10B(n,)7Li reactions using solid state nuclear track detector (SSNTD) for boron neutron capture therapy research. The detection limit of 10B concentration in tumor cells is less than 1·10-3 ppm under our experimental conditions which permits the quantitative determination of 10B in a small number of boronated tumor cells (105/ml = ca. 0.1 mg). Boron quantities in tumor cells determined were well compatible with the tumor cell killing effects of boron neutron capture therapy.  相似文献   
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Efficient constructions of two types of neo-proteoglycan are described. Enzymatically prepared alkyne containing chondroitin 6-sulfate chains and chemically synthesized azido group having compounds are linked by utilizing the copper(I) catalyzed 1,3-dipolar cycloaddition.  相似文献   
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利用色相色谱/质谱联用技术,傅立叶红外及裂解-气相色谱/质谱联用技术,对印刷用上光油的关键成分进行了分析,共鉴定出7种挥发性组分,2种高分子聚合物。  相似文献   
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Immediate allergy is caused by a chemical mediator released from basophile and mast cells via cell degranulation due to reaction between an immunoglobulin E (IgE) antibody, bound with the IgE receptor on the cell membrane, and an antigen. The present authors have established a new method for assaying the enzyme activity of beta-hexosaminidase as an index of chemical mediator release. Using cultured cells instead of conventional methods based on histamine release from mast cells, the present method permits highly accurate mass screening since it uses a well-established cell line of rat basophilic leukemia cells (RBL-2H3). The effects of metal elements on immediate allergic reaction were evaluated using a newly developed assay system. A total of 38 metal elements were investigated for effects on immediate allergic reactions in vitro. These elements were classified by five types on the basis of action on beta-hexosanimidase release: 1) those which showed very strong inhibitory action, such as ZnCl2 and ZrCl4, 2) those which showed relatively strong inhibitory action, such as CdCl2 and CuCl2, 3) those which showed relatively weak inhibitory action, such as CoCl2 and Pb(NO3)2, 4) those which showed neither inhibitory nor promoting action, such as MnCl2 and SrCl2, and 5) AgNO3, which alone showed promoting action.  相似文献   
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