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991.
992.
Hiroshige Ryosuke Goto Satoru Ichii Risa Shimizu Shota Wada-Hirai Ayako Li Ying-Peng Shimada Yohsuke Otsuka Yuta Makino Kosho Takahashi Hideyo 《Journal of inclusion phenomena and macrocyclic chemistry》2022,102(3-4):327-338
Journal of Inclusion Phenomena and Macrocyclic Chemistry - Antioxidants scavenge free radicals and may help prevent disease. However, due to poor stability, continuous intake is required. This... 相似文献
993.
Shodai Hino Shuhei Satake Hideyuki Shinmori Shigeki Kawabata Kazuya Koumoto Toshio Suzuki Takeshi Nagasaki Kouta Sugikawa Riku Kawasaki Atsushi Ikeda 《化学:亚洲杂志》2020,15(3):365-370
5,15‐Diazaporphyrins, which have a large absorption at wavelengths over 600 nm, were dissolved in water by complex formation with β‐(1,3‐1,6)‐d ‐glucans. Aqueous solutions of these complexes were relatively stable compared with their trimethyl‐β‐cyclodextrin‐complexed analogues. β‐Glucan‐complexed diazaporphyrins showed quenched fluorescence and had low singlet‐oxygen‐generation abilities owing to random self‐aggregation. However, external stimuli, such as the presence of liposomes or intracellular uptake, restored the fluorescence and singlet‐oxygen‐generation abilities of β‐glucan‐complexed diazaporphyrins. Consequently, β‐glucan‐complexed diazaporphyrins showed very high photodynamic activities toward HeLa cells. 相似文献
994.
Kimura H Sato Y Tajima Y Suzuki H Yukitake H Imaeda T Kajino M Oki H Takizawa M Tanida S 《Chemistry & biology》2010,17(12):401-1294
Highlights? ARE activation is involved in cellular protection against oxidative stress ? MIF is a ubiquitous protein with conserved nucleophilic Pro1 in a hydrophobic pocket ? BTZO-1 selectively binds to MIF, and its binding required the intact N-terminal Pro1 ? Binding of BTZO-1 to MIF leads to the ARE activation in cardiomyocytes. 相似文献
995.
996.
Icariside B(5) is one of the widely distributed megastigmane glucosides among plant sources. The absolute structure of icariside B(5) was reinvestigated by chemical conversion from the related compound and the application of the modified Mosher's method. As a result, the structure of icariside B(5) was revised to be (6S,9S)-6,9-dihydroxymegastigman-4-en-3-one 9-O-β-D-glucopyranoside. 相似文献
997.
Makoto Otsuka Koyuki Ibe Yoshihiro Tokudome Hiroyuki Ohshima 《Colloids and surfaces. B, Biointerfaces》2009,73(2):351-359
The effects of nano- and macro-geometrical factors on the hydration kinetics of caffeine (CA) and theophylline anhydrate (TA) tablets at high humidity were investigated using X-ray high-resolution computed tomography (CT). Hydration profiles of CA and TA tablets obtained at 25 and 50 MPa, 96% relative humidity, and 20 °C were measured by weight and X-ray CT. The total tablet volume (G-V) and average tablet density (G-D) calculated based on the volume and weight of tablets, and tablet volume (CT-V) and tablet density (CT-D) were evaluated by X-ray CT. The hydration kinetics of CA and TA tablets followed two-dimensional growth of nuclei (Avrami-Erofee) and three-dimensional phase boundary equations, respectively. The increase in the G-V of TA tablets was initially more than, but later less than, that of CA tablets. The G-D of CA tablets varied extensively and was constant initially, whereas that of TA tablets decreased significantly in the initial stage. The CT-V of CA tablets gradually increased initially, but that of TA tablets increased significantly early on. The inter-granular volume (IG-V) of both tablets decreased initially with large fluctuations, but then increased. The CT-D of CA tablets decreased significantly, but that of TA tablets did not decrease. The hydration kinetics of CA and TA tablets was affected by changes in the geometrical structure of the tablets. X-ray CT is a powerful tool for evaluating dynamic changes inside tablets. 相似文献
998.
Jun Kobayashi Naoki Ohashi Hideyuki Sekiwa Isao Sakaguchi Miyuki Miyamoto Yoshiki Wada Yutaka Adachi Kenji Matsumoto Hajime Haneda 《Journal of Crystal Growth》2009,311(19):4408-4413
Bulk properties of gallium (Ga)- and aluminum (Al)-doped zinc oxide (ZnO) were studied using bulky single-crystalline thick films grown by liquid phase epitaxy (LPE). The highest possible dopant concentration was 1×1019 cm–3 for LPE growth at around 800 °C. The electron concentration was nearly same to the Ga and Al concentrations. The donor binding energy decreased to nearly zero with an increase in dopant concentration, and electron mobility of the sample with relatively high dopant concentration (1×1019 cm–3) was more than 60 cm2 V–1 s–1 at room temperature. The LPE technique is a potential solution for the production of ZnO for optical applications because the well-defined excitonic luminescence could be seen from the LPE-grown-doped single-crystals. 相似文献
999.
1000.
Kazuya Fukunaga Kazuaki Kouyama Masafumi Hashimoto Hideyuki Kunugita Kazuhiro Ema Akihiko Kikuchi Katsumi Kishino 《Journal of luminescence》2009,129(12):1735-1738
We have measured the optical properties of wurtzite InN nanocolumns and film by photoluminescence (PL) measurements at temperatures from 5 to 300 K and analyzed the PL spectra by fitting with the free-electron recombination bound (FERB) model. For the top-linked InN nanocolumns, we observed strong PL intensity compared to the InN film sample. The PL spectra were asymmetrical with low-energy tails and a red-shift of the PL peak energy position was observed with increasing temperature. However, for the separated InN nanocolumns, we observed weak PL intensity and symmetrical PL spectra. Analyzing the spectra shape of the top-linked InN nanocolumns at 5 K using the FERB model, we evaluated the intrinsic bandgap energy and carrier density of InN nanocolumns to be 0.69 eV and 2.5×1017 cm−3, respectively. 相似文献