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81.
Inside Cover: Photoinduced Formation of an Azobenzene‐Based CD‐Active Supramolecular Cyclic Dimer (Chem. Eur. J. 18/2015) 下载免费PDF全文
82.
Le Hoang Lam Tomoko Shimamura Sachiyo Manabe Munetaka Ishiyama Hiroyuki Ukeda 《Analytical sciences》2008,24(8):1057-1060
A newly synthesized substrate, 3-hydroxybutyrylglycyl-glycyl-glycine (3HB-GGG), was applied to the assay of ACE-inhibiting activity to overcome the smaller selectivity and sensitivity of the conventional method. In this study, an ACE-inhibiting assay was improved by the use of a water-soluble tetrazolium salt, 4-[3-(4-iodophenyl)-2-(4-nitrophenyl)-2H-5-tetrazolio]-1,3-benzene disulfonate sodium salt (WST-1), for the detection of 3-hydroxybutyrate, derived from 3HB-GGG. The optimized conditions were as follows: 0.333 mM NAD(+), 0.333 mM WST-1, 0.1 mM EDTA, 0.633 U ml(-1) diaphorase, and 0.700 U ml(-1) 3-hydroxybutyrate dehydrogenase. The developed assay was efficiently applicable to evaluate the ACE-inhibiting activity of practical ACE inhibitors. 相似文献
83.
Yoshikazu Shizuri Jiro Ohtsuka Seiji Kosemura Yukimasa Terada Shosuke Yamamura 《Tetrahedron letters》1984,25(48):5547-5550
Some macrocyclic diterpenes derived from euphohelioscopin A and euphornin have been stereoselectively converted into the jatropholane- and daphnane-type compounds and the known tricyclic compound which has been treated with phCOCl - pyridine to afford euphohelionone, the new type of diterpene isolated from euphorbia helioscopia L. 相似文献
84.
Yosuke Kawai Toshinobu Hondo Kirk R. Jensen Michisato Toyoda Kentaro Terada 《Journal of the American Society for Mass Spectrometry》2018,29(7):1403-1407
Two different types of data acquisition methods, “averaging mode” and “ion-counting mode”, have been used in a time-of-flight (TOF) mass spectrometry. The most common method is an averaging mode that sums waveform signals obtained from each flight cycle. While it is possible to process many ions arriving at the same TOF in one flight cycle, low-abundance ions are difficult to measure because ion signals are overwhelmed by noises from the detection system. An ion-counting mode is suitable for the detection of such low-concentration ions, but counting loss occurs when two or more ions arrive at the detector within the dead time of the acquisition system. In this study, we introduce a technique that combines two methods to measure target ions with a high concentration difference, i.e., averaging mode and ion-counting mode are used simultaneously for high abundant and trace ions, respectively. By processing waveforms concurrently during data acquisition, one can choose to analyze either or both types of data to achieve a highly quantitative mass spectrum over a wide range of sample concentrations. The result of the argon isotope analysis shows that this method provides a more accurate determination of the isotope ratio compared to averaging mode alone at one-twentieth of the analysis time required by ion-counting alone. 相似文献
85.
Terada A Yuasa A Tsuneda S Hirata A Katakai A Tamada M 《Colloids and surfaces. B, Biointerfaces》2005,43(2):99-107
Surface-modified polyethylene (PE) membrane sheets were prepared by the radiation-induced graft polymerization (RIGP) of an epoxy-group-containing monomer, glycidyl methacrylate (GMA). The epoxy ring of GMA was opened by introducing diethylamine (DEA) or sodium sulfite (SS). We examined the properties of these sheets by measuring the amount of grafting polymer, surface roughness and membrane potential, and also investigated the adhesion of five Gram-negative bacteria, Escherichia coli, Pseudomonas aeruginosa, Pseudomonas putida, Pseudomonas fluorescens and Paracoccus denitrificans, onto the prepared sheet surfaces. A linear relationship between the degree of grafting (dg) and surface roughness was observed. Moreover, membrane potential was dependent on the amount of DEA or SS as the ionizable group. These results indicate that RIGP enables the control of the physicochemical properties of such a sheet surface by adjusting dg and the subsequent conversion of functional groups. A batch test on bacterial adhesion onto the sheets clarified that the DEA-containing sheet (DEA sheet) exhibited an adhesion rate constant, k, significantly greater than those of other types of sheet. Clearly, the adhesion rate constant of the DEA sheet increased with dg, indicating that electrostatic interaction is the most decisive factor for bacterial adhesion when it works as an attractive force. Furthermore, the densities of bacteria adhering onto the GMA-containing sheet (GMA sheet) and the SS-containing sheet (SS sheet) were almost the same as that onto a PE sheet, whereas that onto a DEA sheet significantly increased. Thus, the introduction of the GMA- and SS-containing graft chain did not have much influence on bacterial adhesion onto the surfaces, supporting the conclusion that the promotion of bacterial adhesion onto the GMA and SS sheets was due to an increase in surface area resulting from RIGP. Moreover, the scanning electron microscopy images of the sheet surfaces indicate that the conditions and morphologies of initial bacterial adhesion are dependent on surface properties, particularly membrane potential. 相似文献
86.
Yoshinobu Nakai Keiji Yamamoto Katsuhide Terada Hidetoshi Horibe 《Journal of inclusion phenomena and macrocyclic chemistry》1984,2(3-4):523-531
Summary The effect of tri-O-methyl--cyclodextrin(methyl--CD) on the partition coefficients of drugs, such as p-nitrophenol, salicylic acid, benzoic acid, and aspirin, was studied at 25°C. The partition coefficients of these drugs were increased linearly with methyl--CD concentration. The increase of partition coefficients was interpreted by the 11 complex formation between methyl--CD and the drug in CHCl3 phase.The interaction between p-nitrophenol and methyl--CD in solution was studied by UV and PMR spectroscopies. It was concluded that p-nitrophenol is included in the cavity of methyl--CD in both aqueous solution and CHCl3 solution.Inclusion compounds of these drugs with methyl--CD in the solid state were studied by X-ray diffractometry, IR spectroscopy, and DSC measurements. 11 crystalline inclusion compounds were obtained from hot water. It is also suggested that amorphous inclusion compound was obtained by the grinding of drug with methyl--CD.The dissolution rate and the bioavailability of ketoprofen were significantly increased in the presence of methyl--CD. The bioavailability of ketoprofen after oral administration with methyl--CD to rats was 3.7 times that of ketoprofen alone. 相似文献
87.
A method is described for separating technetium from rhenium in hydrochloric acid medium by liquid-liquid extraction with potassium xanthate and carbon tetrachloride. The effects of the concentration of various acids, concentration of xanthate, different solvents and diverse ions have been investigated. 相似文献
88.
Quantitative structure-activity relationship (QSAR) analysis of 3-phenyl-1-indanamines, 1-amino-4-aryltetralins, and 6-phenylpyrrolo[2,1-a] isoquinolines has been performed for catecholamine-uptake inhibition activities. Similar equations were obtained for these series of congeners indicating a common tendency that the increase in hydrophobicity of the substituents on the primary phenyl ring (ring C) enhances the activity, and the important aromatic ring which interacts with the receptor is this ring C. It was also indicated that the effect of the introduction of the second N-methyl group differs depending on the series of congeners. These results were used to characterize a binding model for a pharmacophore, which comprised a phenyl ring and a basic nitrogen. This model defined the necessary three-dimensional features leading to the uptake inhibition, and degree of fitness with this model predicted the strength of the activity. Furthermore, it appeared likely that a substituent existing in a specific region of the inhibitor molecule causes a steric hindrance with the receptor site and reduces the activity. 相似文献
89.
Yasuhiko Haneda Hiroyuki Terada Michie Yoshida Akira Ueda Susumu Nagai 《Journal of polymer science. Part A, Polymer chemistry》1994,32(14):2641-2652
Various aliphatic polyesters such as poly (ethyleneadipate), poly (tetramethylene adipate), poly (caprolactone), and poly (carbonate) were condensed with 4,4'-azobis-4-cyanopentanoyl chloride to prepare macro-azo-initiators. Their thermal properties, observed by differential scanning calorimetry, showed similar decomposition behavior to each other. Block copolymers containing each of these polyesters as a block segment combined with polystyrene or poly (methylmethacrylate) have been derived by the polymerization of monomers initiated with these macro-azo-initiators. © 1994 John Wiley & Sons, Inc. 相似文献
90.
K. Mizoguchi K. Terada Y. Naito Y. Kamiya S. Tsuchida S. Yano 《Colloid and polymer science》1997,275(1):86-90
Blends of poly(ethylene-
co-5.4 mol% 3,5,5-trimethylhexyl methacrylate) (PE-TMHM) with poly(dimethylsiloxane) (PDMS) were prepared in the PDMS content
range from 0 to 20%. The miscibility was studied for PE-TMHM–PDMS blends by DSC, dynamic mechanical and microscopic spectroscopy,
and the gas permeability was measured for O2, N2 and CO2 as function of PDMS content. PE-TMHM and PDMS were partially miscible with each other below 20 wt% of PDMS content. The permeability
coefficients (P) for O2, N2 and CO2 were increased by the blending of PDMS to PE-TMHM. The change of P for O2 with PDMS content well reflected the partially miscible phase separation behavior.
Received: 10 June 1996 Accepted: 14 August 1996 相似文献