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101.
102.
The purpose of the present study was to locate a controversial site and to make generalizations about the effects of thyroidectomy (Tx) and streptozocin (STZ) on the distribution pattern of an individual fatty acid in microsomal fractions of the animals thus treated. The results obtained were compared with the reported data. The effects of Tx on C18:1, C18:2, and all detectable C20 and C22 species harmonized well within each species; however the effects of Tx on C16 species and C18:0 varied within each species. Meanwhile, all the effects of STZ were identical within the species, but were often in opposite directions between two adjacent species; e.g. C18:0 and C18:1. These findings strongly indicate that desaturation and elongation sites were independently affected by either Tx or STZ. The comparison suggested that controversial effects appeared in the distribution proper to species C18. Therefore, delta 9-desaturase activity in the microsomal fractions was measured, using stearoyl coenzyme A (CoA) as substrate, resulting in some partial reduction in Tx, but complete suppression in STZ-treated animals. The total contents of phospholipid and cholesterol in the microsomes were also measured. Results showed a significant increase in microsomes within the STZ-group, but almost no change in the Tx-group, indicating that the changes in an individual fatty acid component and in the total fatty acids do not always take place in parallel. 相似文献
103.
Matsunaga G Toi K Kawada S Kotani J Suzuki C Matsuoka K;CHS Group 《Physical review letters》2005,94(22):225005
A novel method of exciting shear Alfvén waves using electrodes inserted in a plasma was developed for basic study of Alfvén eigenmodes in a heliotron/torsatron plasma. The electrodes can induce excitation current along the confinement field line, and generate magnetic perturbations perpendicular to the confinement field. By sweeping the frequency of the current in a cold plasma, the toroidicity-induced Alfvén eigenmode was resonantly excited at the predicted frequency and radial location. Plasma response to the applied magnetic perturbations indicates a fairly large damping rate caused by continuum damping. 相似文献
104.
T Kumamoto K Toyooka M Nishida H Kuwahara Y Yoshimura J Kawada S Kubota 《Chemical & pharmaceutical bulletin》1990,38(9):2595-2596
Antithyroid activity of 2,4-dihydro-3H-1,2,4-triazole-3-thiones and thiosemicarbazones was tested by measuring the uptake ratio of thyroid: serum (T/S) of 125I through the mouse thyroid. Substitution with an alkyl group at the 5-position of the triazole nucleus remarkably increased the activity but substitution at the N-2 and/or N-4 positions caused a significant decrease in the activity, indicating the necessity of unsubstituted thioureylene moiety for the antithyroid activity. Thiosemicarbazone derivatives which are an open ring structure of triazoles showed comparable antithyroid activities to those in a ring form, but one thiosemicarbazone showed a much higher toxicity than the corresponding ring form compound. This suggests that the ring structure is not essential for the activity but is necessary to reduce toxic effect. Of fourteen compounds tested, 5-methyl-2,4-dihydro-3H-1,2,4-triazole-3-thione was the most potent antithyroid compound with low toxicity, with a potency tenfold that of propylthiouracil, a drug currently used. 相似文献
105.
Shogo Miyoshi Shigenori Onuma Hiroshige Matsumoto Tatsuya Kawada Harumi Yokokawa 《Journal of solid state chemistry》2004,177(11):4112-4118
The single-phase region of La1−xSrxCrO3 (x=0.1, 0.2, 0.3) was precisely determined as a function of temperature, PO2 and Sr content. The powders with the nominal composition of La1−xSrxCrO3 were equilibrated under various conditions, and then identified by XRD analyses. To confirm the equilibration, two independent experiments were performed for each composition observing (i) the precipitation of the second phase from a single-phase solid solution, and (ii) the formation of the single phase from the constituent oxides. Two kinds of second phases, SrCrO4 and an unknown phase, were observed depending on the conditions. The second phases tended to appear at low temperature, in high PO2 and with a large Sr content. The single-phase regions obtained via the two equilibration routes were in good agreement with each other. The thermodynamic calculations on the supposition of ideality of the solid solution essentially reproduced the experimental results. When this material is used as the interconnects of solid oxide fuel cells, much attention should be paid to its relatively narrow solubility range of Sr; for example, the solubility limit is approximately 0.1 under a typical cathode-side condition (1273 K, air). 相似文献
106.
A novel synthetic method for mixed acetals (acetyl methyl acetals) by electrolysis of hemithioacetals derived from methoxy- (phenylthio)methane is newly developed. Synthetic application of these mixed acetals as an aldehyde equivalent is also demonstrated. 相似文献
107.
Shigenori Onuma Keiji Yashiro Kenichi Kawamura Tatsuya Kawada Natsuko Sakai 《Journal of solid state chemistry》2003,170(1):68-74
The chemical stability of perovskite-type La1−xCaxCrO3−δ (x=0.1, 0.2, 0.3) in high oxygen partial pressure, PO2, was investigated with three methods: thermogravimetry, XRD analysis, and thermodynamic calculation. The second phase, CaCrO4 was observed by XRD analysis on the powder equilibrated in high PO2. Thermogravimetry under fixed temperatures sensitively detected the segregation of the second phase in the form of oxygen incorporation, because oxidation of chromium ion accompanies the segregation. The second phase tended to appear in high PO2 and at low temperature. The single-phase regions of La1−xCaxCrO3−δ obtained from the two experimental methods well agreed with each other. The results of thermodynamic calculation on the assumption of ideality of the solid solution also agreed with the experimental results. These results suggested the sufficient chemical stability of La1−xCaxCrO3−δ in high PO2 concerning the application to an interconnector of high-temperature solid oxide fuel cells; for example, La0.7Ca0.3CrO3−δ is stable at 1273 K in air. 相似文献
108.
A simultaneous micro-determination of nicotinamide and its major metabolites, N1-methyl-2-pyridone-5-carboxamide (2-py) and N1-methyl-4-pyridone-3-carboxamide (4-py) by high-performance liquid chromatography is described. The method employs a 7-ODS-L (250 mm X 4.6 mm I.D., particle size 7 microns) column eluted with 10 mM potassium dihydrogenphosphate-acetonitrile (96:4, v/v; pH adjusted to 3.0 by the addition of concentrated phosphoric acid) at a flow-rate of 1.0 ml/min. The UV detector was set at 260 nm. The detection limits for nicotinamide, 2-py and 4-py were 10 pmol (1.22 ng), 2 pmol (304 pg) and 2 pmol (304 pg), respectively, at a signal-to-noise ratio 5:1. Isonicotinamide was used as an internal standard. The technique was applied to the analysis of rat and human urines. The total analysis time was ca. 15 min. 相似文献
109.
Dr. Masahiro Kawada Mr. Ryo Tsuyusaki Dr. Kosuke Nakashima Dr. Hiroshi Akutsu Dr. Shin-ichi Hirashima Prof. Takashi Matsumoto Dr. Hikaru Yanai Prof. Tsuyoshi Miura 《化学:亚洲杂志》2021,16(16):2272-2275
An improved diaminomethylenemalononitrile organocatalyst, bearing a N,N-disubstituted structure, promoted enantioselective conjugate addition reaction of α-branched aldehydes with vinyl sulfone, affording adducts with excellent enantioselectivities (up to 96% ee). Mechanistic studies revealed that the diaminomethylenemalononitrile motif holds the vinyl sulfone substrate using a single hydrogen bond accompanied by multiple weak interactions, including electrostatic C−H⋅⋅⋅O interactions. 相似文献
110.
Kenji Kawada Akinori Arimura Tatsuo Tsuri Masahiro Fuji Tadafumi Komurasaki Shuji Yonezawa Akira Kugimiya Nobuhiro Haga Susumu Mitsumori Masanao Inagaki Takuji Nakatani Yoshinori Tamura Shozo Takechi Teruhiko Taishi Junji Kishino Mitsuaki Ohtani 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》1998,110(7):1015-1017