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31.
Hiroya Yamaguchi Yoshie Yotsukura Hirosaku Sata Yoko Watanabe Hajime Hirose Noriko Kobayashi Diane M. Bless 《Journal of voice》1993,7(3)
A voice therapy program using pushing exercises to correct glottal incompetence is described. The program utilizes various types of instrumentation to determine whether or not a given patient is likely to benefit from the treatment. The program also provides feedback of target voices. Three cases with incomplete glottal closure and subsequent vocal dysphonia characterized by an asthenic breathy quality are used to illustrate the program. Details of the program, termination criteria, and problems and precautions learned from treating 29 patients over a 3-year period are presented. 相似文献
32.
Kyoko TakahashiKenichiro Hashimoto Ayako FujiyamaJunko Yamada Noriko KobayashiMasuo Morisaki Sayaka NakanoNoriyuki Hara Yoshinori Fujimoto 《Tetrahedron letters》2003,44(2):341-344
Feeding of the chemically prepared [24-13C, 24-2H]desmosterol to cell-free systems derived from rat liver and silkworm gut and to cultured cells of Oryza sativa followed by deuterium-decoupled 1H, 13C shift correlation NMR analysis of the biosynthesized cholesterol revealed the stereospecific incorporation of hydrogen atoms from the re-face of the C-24 position of desmosterol. 相似文献
33.
POSSIBLE ROLE OF METALLOTHIONEIN IN THE CELLULAR DEFENSE MECHANISM AGAINST UVB IRRADIATION IN NEONATAL HUMAN SKIN FIBROBLASTS 总被引:1,自引:0,他引:1
Shizuko Kobayashi Yumiko Hirota Junko Sayato-Suzuki Makoto Takehana Hisao Nishimura Noriko Nishimura Chiharu Tohyama 《Photochemistry and photobiology》1994,59(6):650-656
Abstract: The role of metallothionein (MT) in protecting skin cells against UVB irradiation was investigated. Fibroblast strains from normal adult (HS-K) and neonatal (NB1RGB) human skins as well as keratinocyte strains from human skin (SV40-HSK) and newborn Balb/c mouse skin (Pam 212) were exposed to UVB irradiation.
The sensitivity of HS-K and NB1RGB cells to UVB irradiation was similar; those of SV40-HSK and Pam 212 cells were two- and six-fold as sensitive to UVB irradiation as HS-K cells, respectively. The HS-K cells contained the greatest cellular reduced form of glutathione (GSH) levels compared to the three other skin cells: the levels were 13-, 7- and 6-fold of those in NB1RGB, SV40-HSK and Pam 212 cells, respectively. These results indicated that the sensitivity of skin cells to UVB irradiation was not always associated with their endogenous GSH levels. In particular, despite the fact that NB1RGB cells contained a relatively small amount of GSH, they were less sensitive to UVB irradiation.
NB1RGB cells contained 4–30 times more MT than those in other skin cells examined. The sulfhydryl residues of MT molecules in the NB1RGB cells were estimated to be mostly unoccupied by metals, suggesting they act in a similar way to those of GSH. Moreover, NB1RGB cells in which the MT content was elevated by dexamethasone (1 μ M ) or Zn2+ (7 μg/mL) treatment were more resistant to UVB irradiation than nontreated ones.
These results suggest that, at least in neonatal human skin fibroblasts, MT may play a role in protection against UVB irradiation. 相似文献
The sensitivity of HS-K and NB1RGB cells to UVB irradiation was similar; those of SV40-HSK and Pam 212 cells were two- and six-fold as sensitive to UVB irradiation as HS-K cells, respectively. The HS-K cells contained the greatest cellular reduced form of glutathione (GSH) levels compared to the three other skin cells: the levels were 13-, 7- and 6-fold of those in NB1RGB, SV40-HSK and Pam 212 cells, respectively. These results indicated that the sensitivity of skin cells to UVB irradiation was not always associated with their endogenous GSH levels. In particular, despite the fact that NB1RGB cells contained a relatively small amount of GSH, they were less sensitive to UVB irradiation.
NB1RGB cells contained 4–30 times more MT than those in other skin cells examined. The sulfhydryl residues of MT molecules in the NB1RGB cells were estimated to be mostly unoccupied by metals, suggesting they act in a similar way to those of GSH. Moreover, NB1RGB cells in which the MT content was elevated by dexamethasone (1 μ M ) or Zn
These results suggest that, at least in neonatal human skin fibroblasts, MT may play a role in protection against UVB irradiation. 相似文献
34.
35.
Yamada K Wada N Onaka H Matsubara R Isobe R Inagaki M Higuchi R 《Chemical & pharmaceutical bulletin》2005,53(7):788-791
An ante-iso type regio-isomer on the long chain base moiety of a glucocerebroside, HLC-2-A, has been isolated from its parent glucocerebroside molecular species HLC-2 composed of iso and ante-iso isomers, from the less polar lipid fraction of a chloroform/methanol extract of the sea cucumber Holothuria leucospilota. Reverse-phase HPLC that included a recycling system was effective in separating the regio-isomer from its counterpart, revealing a very close resemblance in structure. Other typical glucocerebroside molecular species HLC-1 and HLC-3 were obtained together with HLC-2. The structures of these glucocerebrosides were determined on the basis of chemical and spectroscopic evidence. 相似文献
36.
Noriko Mizoguchi 《Journal of Functional Analysis》2005,220(1):214-227
The present paper is concerned with a Cauchy problem for a semilinear heat equation
(P) 相似文献
37.
Macías-Ruvalcaba NA Okumura N Evans DH 《The journal of physical chemistry. B》2006,110(43):22043-22047
The electrochemical reduction of 3,5-di-tert-butyl-1,2-benzoquinone, 1, has been studied in acetonitrile with added 2,2,2-trifluoroethanol, 2. At low concentrations of 2 the reaction proceeds by the following pathway: reduction of the quinone (Q) to its anion radical (Q*-) followed by complexation of the anion radical with 2 (HA) and the further reduction of the hydrogen-bonded complex (Q*- (HA)) to form HQ- and A-. The latter reaction is a concerted proton and electron- transfer reaction (CPET). At higher concentrations of 2, the pathway changes. The first steps remain the same, but now Q*- (HA) is reduced to HQ- via a disproportionation reaction with Q*- along with proton transfer from HA to Q*- to form HQ* which is reduced to HQ-. The only mechanism that could be found which would account for all of the data involves proton transfer to Q*- occurring within a higher complex, Q*-(HA)3. 相似文献
38.
39.
Noriko Mizoguchi 《Journal of Differential Equations》2006,227(2):652-669
We consider a Cauchy problem for a semilinear heat equation
(P) 相似文献
40.
Kanna Adachi Tomoshi Yamada Hayate Ishizuka Mana Oki Shunsuke Tsunogae Noriko Shimada Osamu Chiba Tatsuya Orihara Prof. Dr. Masafumi Hidaka Prof. Dr. Takatsugu Hirokawa Dr. Minami Odagi Prof. Dr. Keiichi Konoki Prof. Dr. Mari Yotsu-Yamashita Prof. Dr. Kazuo Nagasawa 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(9):2025-2033
A novel series of C12-keto-type saxitoxin (STX) derivatives bearing an unusual nonhydrated form of the ketone at C12 has been synthesized, and their NaV-inhibitory activity has been evaluated in a cell-based assay as well as whole-cell patch-clamp recording. Among these compounds, 11-benzylidene STX ( 3 a ) showed potent inhibitory activity against neuroblastoma Neuro 2A in both cell-based and electrophysiological analyses, with EC50 and IC50 values of 8.5 and 30.7 nm , respectively. Interestingly, the compound showed potent inhibitory activity against tetrodotoxin-resistant subtype of NaV1.5, with an IC50 value of 94.1 nm . Derivatives 3 a – d and 3 f showed low recovery rates from NaV1.2 subtype (ca 45–79 %) compared to natural dcSTX ( 2 ), strongly suggesting an irreversible mode of interaction. We propose an interaction model for the C12-keto derivatives with NaV in which the enone moiety in the STX derivatives 3 works as Michael acceptor for the carboxylate of Asp1717. 相似文献