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101.
H Nagase S Imaide T Yamada S Hirayama T Nemoto N Yamaotsu S Hirono H Fujii 《Chemical & pharmaceutical bulletin》2012,60(8):945-948
On the basis of the three-dimensional pharmacophore model of opioid κ agonists, we simplified the structure of nalfurafine (selective κ agonist) to find the essential structural moieties for binding the opioid receptors, especially κ receptor type. As a result, we found that the trans-fused decahydroisoquinoline derivatives without a phenol ring bound the opioid receptor in micromolar order and that both the amide side chain and the nitrogen substituted by the cyclopropylmethyl group were indispensable moieties for eliciting the κ selectivity. The simple decahydroisoquinoline without amide side chain also bound the opioid receptor without receptor type selectivity, suggesting that the message-address concept would be applicable to even these simple derivatives. These findings that the simple decahydroisoquinoline derivatives showed the affinities for the opioid receptors, especially some of the compounds showed κ selectivity, are the first example in the opioid field. 相似文献
102.
Ken Kitano Ryo Sasaki Terukazu Nogi Takaaki A. Fukami Atsushi Nakagawa Kunio Miki Isao Tanaka 《Journal of Crystal Growth》2000,210(4):819-823
Protein crystallization experiments under microgravity were performed by using commercial vapor diffusion apparatus (CVDA) hardware on the STS-84 shuttle mission. Chaperonin-60, GrpE, the B subunit of V-type ATPase, and the selenomethionine substituted proteins of macrophage migration inhibitory factor (MIF) were selected as target proteins. The results indicate that microgravity positively affected their crystal growth, supporting the practical utilization of microgravity for the protein structure determination. 相似文献
103.
Takahiro Yamada Hisanori Yamane Takaaki Ohta Takenari Goto Takafumi Yao 《Crystal Research and Technology》2007,42(1):13-17
GaN crystals were prepared by heating a Ga melt with 1 at% Li3N against Ga at 750 °C in Na vapor under N2 pressures of 0.4–1.0 MPa. The GaN crystals grown at 1.0 MPa of N2 were colorless and transparent prismatic, having a size of approximately 0.7 mm in length. A secondary ion mass spectrometry (SIMS) showed the contaminant of lithium in the obtained crystals. A large broad yellow band emission peak of 2.28 eV was observed at room temperature in the photoluminescence spectrum in addition to the near band emission peak of GaN at 3.39 eV and a small broad satellite emission at 3.24 eV. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
104.
Takaaki NISHIMURA Masayasu TANAKA Natsuko MORIKOSHI Tamaki YOSHIZAWA Ryo MIYACHI 《Physical Therapy Research》2021,24(3):240
Objective: To clarify the effect of intervention with dynamic motor control exercise (DMCE) for the lumbar region on low back pain in sedentary office workers (SOWs). Methods: The participants comprised 32 SOWs with low back pain who were randomly categorized into two groups: the DMCE group and the normal trunk exercise (NTE) group. Both groups performed each exercise for three days per week for 8 weeks. The primary endpoints were evaluated for the lumbar and hip flexion angles during trunk forward bending, effect of low back pain on activities of daily living (using the Oswestry Disability Index), and intensity of low back pain (using the Visual Analog Scale) pre- and post-intervention. The extent of changes was calculated by subtracting the pre-intervention value from the post-intervention value and was compared between the two groups using an unpaired t-test. Results: The extent of changes in the lumbar flexion and hip flexion angles at 10° of trunk forward bending were significantly greater in the DMCE group than in the NTE group, and no significant differences were noted between the two groups at other angles of trunk forward bending. The extent of changes in the Oswestry Disability Index and the Visual Analog Scale scores were significantly greater in the DMCE group than in the NTE group. Conclusion: DMCE is effective in improving motor control in the lumbar region and hip joints, thereby ameliorating low back pain in SOWs. 相似文献
105.
Prof. Dr. Kennosuke Itoh Shun-ichi Nagao Prof. Dr. Ken Tokunaga Dr. Shigeto Hirayama Dr. Fumika Karaki Dr. Takaaki Mizuguchi Dr. Kenichiro Nagai Noriko Sato Dr. Mitsuaki Suzuki Prof. Dr. Masashi Hashimoto Prof. Dr. Hideaki Fujii 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(16):5171-5179
1,2,3,4-Tetrahydroquinolines should be applicable to the development of new pharmaceutical agents. A facile synthesis of 1,2,3,4-tetrahydroquinolines that is achieved by a photoinduced formal [4+2] cycloaddition reaction of acyclic α,β-unsaturated amides and imides with N,N-dialkylanilines under visible-light irradiation, in which a new IrIII complex photosensitizer, a thiourea, and an oxidant act cooperatively in promoting the reaction, is reported. The photoreaction enables the synthesis of a wide variety of 1,2,3,4-tetrahydroquinolines, while controlling the trans/cis diastereoselectivity (>99:1) and constructing contiguous stereogenic centers. A chemoselective cleavage of an acyclic imide auxiliary is demonstrated. 相似文献
106.
107.
108.
Takaaki Sugimura Yuji Minoura 《Journal of polymer science. Part A, Polymer chemistry》1966,4(11):2735-2746
The effect of diphenyl thiourea (DPTU) on the radical polymerization of methyl methacrylate (MMA) has been studied in benzene solution at 50°C. with the use of cumene hydroperoxide (CHP), p-menthane hydroperoxide (PMHP), tert-butyl perbenzoate (tBPBz), di-tert-butyl peroxide (DBP), and dicumyl peroxide (DCP) as initiators. In the CHP-initiated polymerization, the rate of polymerization increased appreciably on addition of DPTU with a linear dependence on the square root of DPTU concentration up to a maximum which was observed when the ratio of the concentration of CHP to DPTU was 2.5. Then the rate decreased gradually with increasing DPTU concentration in the range greater than the above ratio. It was found from kinetic studied that the overall polymerization rate Rp was expressed by the equation: Rp = K[peroxide]1/2 [DPTU]1/2[MMA], where K is the rate constant, α = 1.2 for CHP and α = 1.0 for tBPBz. It was thought that the acceleration effect observed was due to a redox reaction caused by the interaction of a peroxide–monomer and/or a peroxide–solvent complex with DPTU, and the decrease in the polymerization rate which was observed over a certain concentration of DPTU was due to the action of the oxidized product of DPTU as a transfer agent. The effect of substituents was studied by using para and meta-substituted DPTU. It was found that the polymerization rate increased as electron-donating substituents are added to the benzene ring of DPTU with considerable dependence on Hammett's equation (p = ?0.36). The acceleration effect is also observed for PMPH-and tBPBz-initiated polymerizations, whereas the DCP- and DBP-initiated systems show no effects on the polymerization rate. 相似文献
109.
Dr. Mitsuhiko Morisue Ikuya Ueno Kunihiko Muraoka Dr. Shun Omagari Dr. Takayuki Nakanishi Prof. Yasuchika Hasegawa Dr. Takaaki Hikima Prof. Sono Sasaki 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(30):7322-7329
Quadrupolar interactions of porphyrin bearing two pentafluorophenylethynyl terminals ( 1 ) drove the formation of a successive one-dimensional staircase structure, i.e., J-aggregates, to yield millimeter-length needles with a single-crystalline character in methylcyclohexane solution. In contrast, π-stacked interactions of porphyrin bearing two nonfluorinated phenyl terminals ( 2 ) formed no aggregates in solution. A spin-cast film of 1 also showed bathochromic shift of the Soret and Q bands, indicating the formation of J-aggregates. The molecular arrangement of the J-aggregates was revealed by microbeam glazing-incidence wide-angle X-ray diffraction (GIWAXD), and was in good agreement with the optimized structure generated by density functional theory (DFT) calculations. 相似文献
110.