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141.
Gas-phase ozone was continuously measured by using the chemiluminescent reaction between indigo-5,5′-disulphonate and ozone. A detection limit of 0.4 ppb (v/v) was obtained using a reaction cell of 0.7 ml at a sampling rate of 15.0 ml min?1. The method was applied to the monitoring of ozone in the atmosphere. 相似文献
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T Takeya N Takeuchi T Kasama K Mayuzumi H Fukaya S Tobinaga 《Chemical & pharmaceutical bulletin》1990,38(2):559-561
Honokiol (1), a constituent of Magnoliae cortex, and related synthetic biphenyls inhibited the platelet aggregation induced by a few aggregating agents. In particular, compounds 3, 5, and 10 had an inhibitory effect on platelet activating factor (PAF), which provides a new class of PAF inhibitor. 相似文献
144.
Tokio Takeuchi 《Zeitschrift für Physik A Hadrons and Nuclei》1929,53(1-2):148-150
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Plínio C. Sathler Charles S. Craik Toshihiko Takeuchi Russolina B. Zingali Helena C. Castro 《Applied biochemistry and biotechnology》2010,160(8):2355-2365
Ecotin is a bidentate, fold-specific inhibitor of mammalian serine-proteases produced by Escherichia coli. This molecule may be engineered to increase and/or change its affinity and specificity providing significant biotechnological
potential. Since ecotin binds tightly to serine proteases of the trypsin fold, it may help to identify the role of these enzymes
in different biological processes. In this work, we tested ecotin variants as an affinity purification reagent for identifying
enzymes in samples of tumor progression and mammary gland involution. Initially, we used a commercial source of urokinase-type
plasminogen activator (u-PA) that remained fully active after elution from an affinity column of the ecotin variant (M84R,
M85R). We then successfully identified u-PA from more complex mixtures including lysates from a prostate cancer cell line
and involuting mouse mammary glands. Interestingly, a membrane-type serine protease 1 was isolated from the Triton X-100-solubilized
PC-3 cell lysates, and surprisingly, haptoglobin, a serine-protease homolog protein, was also identified in mammary gland
lysates and in blood. Haptoglobin does not prevent ecotin inhibition of u-PA, but it may act as a carrier within blood when
ecotin is used in vivo. Finally, this affinity purification matrix was also able to identify a thrombin-like enzyme from snake venom using an ecotin
variant directed against thrombin. Overall, the ecotin variants acted as robust tools for the isolation and characterization
of proteins with a trypsin fold. Thus, they may assist in the understanding of the role of these serine proteases and homologous
proteins in different biological processes. 相似文献
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Jun-ichi Matsuo Ryosuke Okuno Kosuke Takeuchi Mizuki Kawano Hiroyuki Ishibashi 《Tetrahedron letters》2010,51(29):3736-3737
Optimized reaction conditions for the preparation of various 2-monosubstituted 3-ethoxycyclobutanones are described. 2-Monoalkyl 3-ethoxycyclobutanones were efficiently prepared by the reaction of the corresponding carboxylic acid chlorides and an excess amount of ethyl vinyl ether in the presence of diisopropylethylamine at 90 °C in a sealed tube. 2-Monoaryl 3-ethoxycyclobutanones were prepared by using 2,6-lutidine as a base in the above-mentioned procedure. 相似文献
150.