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91.
92.
Y Sasaki M Matsui H Fujita M Hosono M Taguchi K Suzuki S Sakurada T Sato T Sakurada K Kisara 《Chemical & pharmaceutical bulletin》1985,33(4):1528-1536
93.
K. Nisimura H. Shimizu K. Imai T. Ichihara N. Matsuoka K. Hatanaka H. Sakai T. Saito K. Hosono M. Kondo A. Okihana 《Nuclear Physics A》1985,432(2):378-388
The differential cross section and the vector and tensor analyzing powers Ay, Axx, Ayy and Axz were measured for the d-4He elastic scattering at 56 MeV. The measurement of Axz was performed using a deuteron beam polarized in the horizontal plane. An optical-model analysis of the experimental data was carried out. The magnitude of the tensor analyzing powers could not be reproduced without the tensor potential. By including the TR type tensor potential, the optical-model calculations give a reasonable reproduction of the experimental data at θc.m. < 120°. The obtained TR tensor potential was much stronger than that predicted by the folding model. The strength of the real TR potential was roughly in accordance with that obtained from the optical-model analysis of d-4He elastic scattering at 20.2 MeV. 相似文献
94.
Tomoya Ito Koji Suda Takuya Kumamoto Waka Nakanishi Toshiko Watanabe Tsutomu Ishikawa Hiroko Seki Masatoshi Kawahata Kentaro Yamaguchi Yasumitsu Ogura Kazuo T. Suzuki 《Molecular diversity》2010,14(1):131-145
The role of o-bisguanidinobenzenes (BGBs) as new Brønsted base ligands for arsenic and phosphoric acids was examined. In solution state, complexation was evaluated by Job’s plot in 1H NMR experiment, indicating a 1:1 complex formation, whereas in solid state crystalline structures of complexes obtained were addressed by X-ray crystallographic analysis and/or solid state 13C NMR experiment, in which 1:2 complexes between the BGB and the acid components were normally formed. Based on these results, Merrifield and Hypogel® resin-anchored BGBs were designed and prepared as the corresponding polymer-supported host ligands. Evaluation of their coordination ability with metal salts (ZnCl2 and CoCl2) and arsenic acid in aqueous media by ICP-MS showed that the latter Hypogel® resin-anchored BGBs acted as effective immobilized base ligands. 相似文献
95.
Fluorescence excitation, multiphoton ionization, and dispersed fluorescence spectra of bare and hydrogen-bonded 2-fluoropyridine with water were measured in a supersonic free jet. For bare 2-fluoropyridine, fluorescence quantum yield decrease in the higher vibronic levels was observed even under collision-free conditions. The inter-system crossing channel was probed experimentally by two color R2PI and found to be negligible. The non-radiative relaxation process of 2-fluoropyridine is mainly governed by the relaxation to the electronic ground state. Electronic spectra of 2-fluoropyridine-(water)(n) (n=1 approximately 3) were also obtained. The hydrogen bond formation with water increases the quantum yield in the higher vibronic levels. Rather low frequency vibrations were observed in the hole burning spectrum of bare 2-fluoropyridine; however, these vibronic bands disappeared with the hydrogen bond formation with water. The appearance of low frequency vibronic bands observed for bare 2-fluoropyridine is ascribed to the existence of closely lying (n,pi) state. 相似文献
96.
A predual of B_σ-spaces is investigated. A predual of a predual of B_σ-spaces is also investigated,which can be used to investigate the boundedness property of the commutators. The relation between Herz spaces and local Morrey spaces is discussed. As an application of the duality results, one obtains the boundedness of the singular integral operators, the Hardy-Littlewood maximal operators and the fractional integral operators, as well as the commutators generated by the bounded mean oscillation(BMO) and the singular integral operators.What is new in this paper is that we do not have to depend on the specific structure of the operators. The results on the boundedness of operators are formulated in terms of B_σ-spaces and B_σ-spaces together with the detailed comparison of the ones in Herz spaces and local Morrey spaces. Another application is the nonsmooth atomic decomposition adapted to B_σ-spaces. 相似文献
97.
Fumihiko Maekawa Okiru Komine Katsushige Sato Tomoyuki Kanamatsu Motoaki Uchimura Kohichi Tanaka Hiroko Ohki-Hamazaki 《BMC neuroscience》2006,7(1):1-13
Background
Results of the Women's Health Initiative Memory Study (WHIMS) raised concerns regarding the timing and formulation of hormone interventions. Conjugated equine estrogens (CEE), used as the estrogen therapy in the WHIMS trial, is a complex formulation containing multiple estrogens, including several not secreted by human ovaries, as well as other biologically active steroids. Although the full spectrum of estrogenic components present in CEE has not yet been resolved, 10 estrogens have been identified. In the present study, we sought to determine which estrogenic components, at concentrations commensurate with their plasma levels achieved following a single oral dose of 0.625 mg CEE (the dose used in the WHIMS trial) in women, are neuroprotective and whether combinations of those neuroprotective estrogens provide added benefit. Further, we sought, through computer-aided modeling analyses, to investigate the potential correlation of the molecular mechanisms that conferred estrogen neuroprotection with estrogen interactions with the estrogen receptor (ER).Results
Cultured basal forebrain neurons were exposed to either β-amyloid25–35 or excitotoxic glutamate with or without pretreatment with estrogens followed by neuroprotection analyses. Three indicators of neuroprotection that rely on different aspects of neuronal damage and viability, LDH release, intracellular ATP level and MTT formazan formation, were used to assess neuroprotective efficacy. Results of these analyses indicate that the estrogens, 17α-estradiol, 17β-estradiol, equilin, 17α-dihydroequilin, equilinen, 17α-dihydroequilenin, 17β-dihydroequilenin, and Δ8,9-dehydroestrone were each significantly neuroprotective in reducing neuronal plasma membrane damage induced by glutamate excitotoxicity. Of these estrogens, 17β-estradiol and Δ8,9-dehydroestrone were effective in protecting neurons against β-amyloid25–35-induced intracellular ATP decline. Coadministration of two out of three neuroprotective estrogens, 17β-estradiol, equilin and Δ8,9-dehydroestrone, exerted greater neuroprotective efficacy than individual estrogens. Computer-aided analyses to determine structure/function relationships between the estrogenic structures and their neuroprotective activity revealed that the predicted intermolecular interactions of estrogen analogues with ER correlate to their overall neuroprotective efficacy.Conclusion
The present study provides the first documentation of the neuroprotective profile of individual estrogens contained within the complex formulation of CEE at concentrations commensurate with their plasma levels achieved after an oral administration of 0.625 mg CEE in women. Our analyses demonstrate that select estrogens within the complex formulation of CEE contribute to its neuroprotective efficacy. Moreover, our data predict that the magnitude of neuroprotection induced by individual estrogens at relatively low concentrations may be clinically undetectable and ineffective, whereas, a combination of select neuroprotective estrogens could provide an increased and clinically meaningful efficacy. More importantly, these data suggest a strategy for determining neurological efficacy and rational design and development of a composition of estrogen therapy to alleviate climacteric symptoms, promote neurological health, and prevent age-related neurodegeneration, such as AD, in postmenopausal women. 相似文献98.
Fumihiko Maekawa Okiru Komine Katsushige Sato Tomoyuki Kanamatsu Motoaki Uchimura Kohichi Tanaka Hiroko Ohki-Hamazaki 《BMC neuroscience》2006,7(1):75
Background
Imprinting behavior is one form of learning and memory in precocial birds. With the aim of elucidating of the neural basis for visual imprinting, we focused on visual information processing. 相似文献99.
Jiazhen Wu Jiang Li Yutong Gong Masaaki Kitano Takeshi Inoshita Hideo Hosono 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(3):835-839
Electrides loaded with transition‐metal (TM) nanoparticles have recently attracted attention as emerging materials for catalytic NH3 synthesis. However, they suffer from disadvantages associated with the growth and aggregation of nanoparticles. TM‐containing intermetallic electrides appear to be promising catalysts with the advantages of both electrides and transition metals in a single phase. LaRuSi is reported here to be an intermetallic electride with superior activity for NH3 synthesis, and direct evidence is provided supporting its electride‐character‐induced catalytic performance. The discussion is made mainly based on the contrasting synthesis rates over the isostructural compounds LaRuSi, CaRuSi, and LaRu2Si2, and the N2 isotope‐exchange reactions over these compounds. Lattice hydride ions, which can reversibly exchange with anionic electrons, are shown to be indispensable in the promotion of NHx formation. The mechanism derived from the present findings provides new guidelines for NH3 synthesis. 相似文献
100.
Hiroko X. Kondo Ayumi Kusaka Colin K. Kitakawa Jinta Onari Shusuke Yamanaka Haruki Nakamura Yu Takano 《Journal of computational chemistry》2019,40(23):2043-2052
Hydrogen-bond (H-bond) interaction energies in α-helices of short alanine peptides were systematically examined by precise density functional theory calculations, followed by a molecular tailoring approach. The contribution of each H-bond interaction in α-helices was estimated in detail from the entire conformation energies, and the results were compared with those in the minimal H-bond models, in which only H-bond donors and acceptors exist with the capping methyl groups. The former interaction energies were always significantly weaker than the latter energies, when the same geometries of the H-bond donors and acceptors were applied. The chemical origin of this phenomenon was investigated by analyzing the differences among the electronic structures of the local peptide backbones of the α-helices and those of the minimal H-bond models. Consequently, we found that the reduced H-bond energy originated from the depolarizations of both the H-bond donor and acceptor groups, due to the repulsive interactions with the neighboring polar peptide groups in the α-helix backbone. The classical force fields provide similar H-bond energies to those in the minimal H-bond models, which ignore the current depolarization effect, and thus they overestimate the actual H-bond energies in α-helices. © 2019 The Authors. Journal of Computational Chemistry published by Wiley Periodicals, Inc. 相似文献