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31.
Kato D Masaike M Majima T Hirata Y Mizutani F Sakata M Hirayama C Kunitake M 《Chemical communications (Cambridge, England)》2002,(22):2616-2617
Novel two-dimensional (2D) cross-linked polysiloxane LB films were prepared and applied for glucose sensing as H2O2-permselective films in order to block other electroactive interferences, such as L-ascorbic acid, L-cysteine, uric acid and acetaminophen; the 2D cross-linked polysiloxane monolayers were remarkably effective in eliminating interfering responses and had a rapid response for glucose, even though the films were only a monolayer thick. 相似文献
32.
The behavior of arsenite, methylarsonic acid, dimethylarsinic acid, trimethylarsine oxide, dimethyl-R-arsine oxides, and trimethyl-R-arsonium compounds (R = carboxymethyl, 2-carboxyethyl, 2-hydroxyethyl) toward sodium borohydride and hot aqueous sodium hydroxide was investigated. The arsines obtained by sodium borohydride reduction of the undigested and digested solutions were collected in a liquid-nitrogen cooled trap, separated with a gas chromatograph, and detected with a mass spectrometer in the selected-ion-monitoring mode. The investigated arsenic compounds were stable in hot 2 mol dm?3 sodium hydroxide except arsenobetaine [trimethyl(carboxymethyl)arsonium zwitterion] that was converted to trimethylarsine oxide, and dimethyl(ribosyl)arsine oxides that were decomposed to dimethylarsinic acid. Hydride generation before and after digestion of extracts from marine organisms allowed inorganic arsenic, methylated arsenic, arsenobetaine, and ribosyl arsenic compounds to be identified and quantified. This method was applied to extracts from shellfish, fish, crustaceans, and seaweeds. 相似文献
33.
Hirotaka Ihara Ken Shudo Chuichi Hirayama Hiroshi Hachisako Kimiho Yamada 《Liquid crystals》1996,20(6):807-809
The L-glutamic acid-derived lipids form organic gels in benzene, which show enantioselective elution of N-dansyl L-phenylalanine from organic gels to aqueous phases. Differential scanning calorimetry and circular dichroism measurements demonstrate that this enantioselectivity occurred through highly-oriented structures of aggregated lipids like those of aqueous lipid membrane systems. 相似文献
34.
Yellow-emitting Vibrio fischeri Y1 modulates its bioluminescence (BL) depending on the dissolved O2 concentration. On supplying O2 to the cells under anaerobiosis, the cells begin to emit striking yellow BL peaking around 535 nm. The enhanced yellow emission reverts reversibly to the original level after O2 is consumed. Moreover, the reversible rise and fall of the yellow emission occurs repeatedly in accord with the repeating cycles of aeration on and off. This indicates that an increase in the cellular amount of yellow fluorescent protein (YFP) is not an immediate cause of the yellow emission enhancement. One suggested explanation is that the activity of YFP originating from its highly fluorescent property is altered by redox interaction with the respiratory components, including the soluble cytochrome c. Under the O2-limited conditions, the cellular YFP molecules, in part, seem to lose the fluorescent property possibly because of being reduced via redox interaction with some respiratory components in reduced form. On stimulating aerobic respiration with O2 supply, the reduced YFP seems to retrieve its fluorescent property via oxidation possibly with both O2, diffused across the cell membrane, and ferricytochrome c, generated during the respiratory turnover. The suggested redox interactions seem primarily to cause the reversible BL modulation. 相似文献
35.
Masanori Miura Takanori Koike Tsukasa Ishihara Fukushi Hirayama Shuichi Sakamoto Minoru Okada 《合成通讯》2013,43(24):3809-3820
A one‐pot synthetic procedure for 2,2′‐disubstituted biaryls was developed via a Suzuki cross‐coupling reaction of aryl triflates in a biphasic solvent system. The effects of various bases and solvents were investigated. Results showed that the Na2CO3–toluene/H2O combination gave the highest yields. 相似文献
36.
Among several derivatives of 9-benzoylanthracene investigated, only 9-benzoyl 10-cyanoanthracene having the largest λ o–o value showed a large temp 相似文献
37.
Masahiro Yamaguchi Kanako Miyano Shigeto Hirayama Yusuke Karasawa Kaori Ohshima Eiko Uezono Akane Komatsu Miki Nonaka Hideaki Fujii Keisuke Yamaguchi Masako Iseki Masakazu Hayashida Yasuhito Uezono 《Molecules (Basel, Switzerland)》2022,27(20)
Opioid receptors (ORs) are classified into three types (μ, δ, and κ), and opioid analgesics are mainly mediated by μOR activation; however, their use is sometimes restricted by unfavorable effects. The selective κOR agonist nalfurafine was initially developed as an analgesic, but its indication was changed because of the narrow safety margin. The activation of ORs mainly induces two intracellular signaling pathways: a G-protein-mediated pathway and a β-arrestin-mediated pathway. Recently, the expectations for κOR analgesics that selectively activate these pathways have increased; however, the structural properties required for the selectivity of nalfurafine are still unknown. Therefore, we evaluated the partial structures of nalfurafine that are necessary for the selectivity of these two pathways. We assayed the properties of nalfurafine and six nalfurafine analogs (SYKs) using cells stably expressing κORs. The SYKs activated κORs in a concentration-dependent manner with higher EC50 values than nalfurafine. Upon bias factor assessment, only SYK-309 (possessing the 3S-hydroxy group) showed higher selectivity of G-protein-mediated signaling activities than nalfurafine, suggesting the direction of the 3S-hydroxy group may affect the β-arrestin-mediated pathway. In conclusion, nalfurafine analogs having a 3S-hydroxy group, such as SYK-309, could be considered G-protein-biased κOR agonists. 相似文献
38.
Hidemasa Hidaka Masao Hirayama Kazuhiko Yamada 《Journal of carbohydrate chemistry》2013,32(4):509-522
I. INTRODUCTION Recently the study of oligosaccharides has been extensively pursued in Japan after the findings of the remarkable biofunctions and usefulness of fructooligosac-charides for human health, improving the intestinal microflora and importance in livestock nutrition. 相似文献
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