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237 results on '"Tomura S"'

14. Studies on the oxidation of hexamethylbenzene 1: Oxidation of hexamethylbenzene with nitric acid

Author

Chiba, K, Tomura, S, and Mizuno, T

Subjects
Inorganic And Physical Chemistry
Abstract

The oxidative reaction of hexamethylbenzene (HMB) with nitric acid was studied, and the hitherto unknown polymethylbenzenepolycarboxylic acids were isolated: tetramethylphthalic anhydride, tetramethylisophthalic acid, 1,3,5-, 1,2,4- and 1,2,3-trimethylbenzenetricarboxylic acids. When HMB was warmed with 50% nitric acid at about 80 C, tetramethylphthalic anhydride and tetramethylisophthalic acid were initially produced. The continued reaction led to the production of trimethylbenzenetricarboxylic acids, but only slight amounts of dimethylbenzenetetracarboxylic acids were detected in the reaction mixture. Whereas tetramethylphthalic anydride and tetramethylisophthalic acid were obtained, pentamethylbenzoic acid, a possible precursor of them, was scarcely produced. On the other hand, a yellow material extracted with ether from the initial reaction mixture contained bis-(nitromethyl)prehnitene (CH3)4C6(CH2NO2)2, which was easily converted into the phthalic anhydride.

Published
1986

15. Studies on the oxidation of hexamethylbenzene 2: Preparation of dimethylpyromellitic acid

Author

Chiba, K and Tomura, S

Subjects
Inorganic And Physical Chemistry
Abstract

Hexamethylbenzene (HMB) was difficult to be oxidized with an alkaline potassium permanganate solution, since HMB was insoluble in an aqueous alkaline solution. But, when HMB was warmed with 50% nitric acid for a short time, and then treated with aqueous potassium permanganate, the reaction occurred readily and dimethylpyromellitic acid was obtained. When HMB was warmed with 50% nitric acid for 1 to 2 minutes, a yellow material was produced, which was soluble in hot aqueous potassium hydroxide, though free from carboxylic acids. It contained a little amount of bis-(nitromethyl)prehnitene and several unknown compounds. Further, the heat stability of polyimide prepared by the reaction of tetramethyldimethylpyromellitate with 4,4 prime-diaminodiphenylmethane turned out to be nearly equal to that of polyimide prepared from tetramethylpyromellitate.

Published
1986

35. Long term administration of cyclophosphamide in MRL/1 mice. I. The effects on the development of immunological abnormalities and lupus nephritis.

Author

Shiraki, M., Fujiwara, M., and Tomura, S.

Subjects
LUPUS nephritis, IMMUNOLOGIC diseases, DNA, LYMPH nodes, BLOOD plasma, IMMUNOGLOBULINS, T cells, LYMPHOID tissue
Abstract

Weekly injection of cyclophosphamide (Cy) into MRL/Mp-lpr/lpr (MRL/l) mice, at a dose of 10-20 mg/kg, from 1 month of age prevented the development of generalized lymph node enlargement, decreased serum levels of anti-DNA antibodies and immune complexes, and markedly prolonged their life span. Cy effectively suppressed enhanced differentiation of B cells, as evidenced by decreased number of immunoglobulin secreting cells in the spleen. Cy was also shown to suppress abnormal expansion of Thy-1 positive cells in lymphoid organs of MRL/l mice. These results suggested that Cy prevented the development of murine lupus like syndrome in MRL/l mice through suppression of spontaneous polyctonal B cell activation and also by reducing the number of T cells to exert excessive helper activity on B cells. [ABSTRACT FROM AUTHOR]

Published
1984

39. Preparation of the Langmuir−Blodgett Film of a Clay−Alkylammonium Adduct and Its Use as a Barrier for Interlayer Photoinduced Electron Transfer

Author

Inukai, K., Hotta, Y., Tomura, S., Takahashi, M., and Yamagishi, A.

Abstract

We report on the photophysical application of the multilayer films of an ion-exchange adduct of a clay (synthetic saponite) and an alkylammonium cation (trimethylstearylammonium) as prepared by the Langmuir−Blodgett method. For preparing a film, the adduct was dispersed in chloroform and spread over the surface of pure water. A surface pressure−area isotherm was obtained at 25.0 °C with complete reproducibility. The critical surface area, Ac, was defined as an area where the linear portion of the isotherm was extrapolated to zero surface pressure. From the dependence of Ac on the spread amount of the adduct, it was concluded that the adduct formed a film of a single clay layer at an air−water interface. The floating film was transferred onto a hydrophilic glass substrate or a calcium fluoride plate as a Z-type multilayer film. The film was characterized by X-ray diffraction, infrared absorption spectra, and atomic force microscopy images. The prepared clay film was revealed to act as an efficient barrier for the occurrence of photoinduced electron transfer from an amphiphilic polypyridyl−Ru(II) complex (electron donor) to an amphiphilic acetylacetonato−Ru(III) complex (electron acceptor).

Published
2000

41. Serial changes in independent sitting in adults with severe cerebral palsy.

Author

Miyazaki Y, Iwai K, Matumura S, Miwa T, Yanagisako Y, Yanagi H, and Tomura S

Abstract

We investigated the natural course of independent sitting in 28 institutionalized patients with severe cerebral palsy (CP) and evaluated the factors associated with presence or absence of independent sitting during adulthood. Seventeen subjects (61%) who could not sit at the age of 10 years were never able to reach the milestone of independent sitting. Five (45%) of 11 subjects subsequently lost the ability to sit independently during the early stage of adult life. In adulthood, many of the dependent sitters had poor activities of daily living (ADL) scores and required medical care for respiration and eating/swallowing. Hip dislocation was not directly associated with the presence or absence of independent sitting. We conclude that it is important to prevent further deterioration of swallowing and respiratory functions, as well as the development of deformities or contractures from childhood and to maintain previously acquired motor function and ADL in adults with severe CP. [ABSTRACT FROM AUTHOR]

Published
2004
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