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Electron spin resonance imaging of mouse B16 melanoma 总被引:2,自引:0,他引:2
H Katsuda T Kobayashi H Saito T Matsunaga M Ikeya 《Chemical & pharmaceutical bulletin》1990,38(10):2838-2840
An X-band electron spin resonance (ESR) imaging apparatus with a pin-hole TE102 mode cavity and a rapid scan coil was constructed. Using this apparatus, ESR imaging of melanin in mouse B16 melanoma was observed for the first time. The ESR spectrum of B16 melanoma is similar to that of natural melanin extracted from sepia officinalis in microwave power dependence. 相似文献
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Iwaoka M Komatsu H Katsuda T Tomoda S 《Journal of the American Chemical Society》2004,126(16):5309-5317
To investigate the nature of nonbonded Se...O interactions, three series of 2-substituted benzeneselenenyl derivatives [2-(CHO)C6H4SeX (1), 2-(CH2OH)C6H4SeX, (2), 2-(CH2OiPr)C6H4SeX (3); X = Cl, Br, CN, SPh, SeAr, Me] were synthesized. The 17O NMR absorption observed for 17O-enriched aldehydes 1 appeared upfield relative to benzaldehyde (PhCHO), while the opposite downfield shifts relative to benzyl alcohol (PhCH2OH) were observed for 17O-enriched alcohols 2 and ethers 3. The magnitude of both the upfield and the downfield shifts became larger as the electron-withdrawing ability of a substituent X increased. Quantum chemical calculations at the B3LYP level revealed that for all model compounds the most stable conformer has an intramolecular nonbonded Se.O interaction. Thus, the relative 17O NMR chemical shifts (DeltadeltaO) for 1-3 would reflect the strengths of the Se...O interactions. The natural bond orbital (NBO) analysis demonstrated that the stabilization energy due to an nO --> sigma Se-X orbital interaction (ESe...O) correlates with the Se...O atomic distance on a single curve irrespective of the type of the O atom. On the other hand, the atoms in molecules (AIM) analysis showed that the nonbonded Se...O interactions can be characterized by the presence of a bond critical point, the total energy density (HSe...O) of which decreases with strengthening of the interaction. The results suggested that Se...O interactions have a dominant covalent character rather than an electrostatic one. 相似文献
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Michael Anderson Atsushi Katsuda Yaroslav Kurylev Matti Lassas Michael Taylor 《Inventiones Mathematicae》2004,158(2):261-321
This paper explores and ties together three themes. The first is to establish regularity of a metric tensor, on a manifold with boundary, on which there are given Ricci curvature bounds, on the manifold and its boundary, and a Lipschitz bound on the mean curvature of the boundary. The second is to establish geometric convergence of a (sub)sequence of manifolds with boundary with such geometrical bounds and also an upper bound on the diameter and a lower bound on injectivity and boundary injectivity radius, making use of the first part. The third theme involves the uniqueness and conditional stability of an inverse problem proposed by Gelfand, making essential use of the results of the first two parts. 相似文献
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Closed orbits in homology classes 总被引:2,自引:0,他引:2
Dedicated to Pr. Akihiko Morimoto for his 60th birthday 相似文献
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The temperature and angular dependences of the EPR spectra of Mg[H2O]6SiF6:Mn2+ crystal were investigated in order to clarify the successive phase transitions and existence of the incommensurate phase. Five successive phase transitions were found to occur, and phase II was found to be incommensurately modulated. The modulated structure is caused mainly by the vibrational displacement of the Mg[H2O]2+ 6 ion along the c-axis. The soliton density of this phase is almost independent of temperature and remains equal to unity. 相似文献
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Nanami Hara Shu Fujisawa Mizuki Fujita Mikako Miyazawa Kazuma Ochiai Satoshi Katsuda Tetsuya Fujimoto 《Tetrahedron》2018,74(2):296-302
Kinetic resolution of secondary alcohols by benzoylation using a phosphinite derivative of (1S,2R)-1-amino-2-indanol as the catalyst was investigated. The aminophosphinite catalyst is effective for the kinetic resolution of aryl cycloalkyl carbinols with a small number of examples for organocatalytic kinetic resolution to achieve resolution with s = up to 44. Although the benzoylation of phenylalkanols proceeded with a low selectivity, 1-arylalkanols bearing at least one substituent at the ortho position on the benzene ring or a branched alkyl group on the carbinol carbon were resolved with acceptable selectivity. 相似文献
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Katsuda T Nishijima K Kamura M Nishiwada Y Katoh S 《Journal of chromatography. A》2006,1123(2):182-188
We developed an affinity chromatographic method for simple single nucleotide polymorphism (SNP) detection by use of a single-stranded DNA-coupled column and temperature gradient elution, utilizing the difference in thermal stability between hybridized double-stranded DNAs with and without mismatched base-pairs in the course of temperature gradient elution. We studied experimentally and theoretically the elution behavior of DNAs with and without SNPs in this chromatography and proposed a numerical calculation method based on a thermodynamic dissociation model. The effects of the column volume, flow rate of eluent and heating rate of the column on elution profiles were clarified. For designing DNA ligands, mismatched base-pair positions favorable for detection of SNPs were also explored by use of hybridized DNAs coding a part of the human TP53 gene. 相似文献