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71.
Takayuki Kokawa Hideto Saigusa Iichirou Aino Chiharu Matsuoka Tsuyoshi Nakamura Kumiko Tanuma Kazuo Yamashita Seiji Niimi 《Journal of voice》2006,20(3):414-422
SUMMARY: This study identified that physiologically the superior pharyngeal constrictor muscle at the level of the base of the tongue contributes to retrusive movement of the tongue with constriction of the mid-pharyngeal cavity and possesses unique properties in terms of motor speech control along with the genioglossus muscle. From a kinematic study involving trans-nasal fiberscopy and lateral X-ray fluorography, retrusive movement of the tongue was highly correlated with constrictive movement of the mid-pharyngeal cavity. An electromyographic study revealed that the superior pharyngeal constrictor muscle at the level of the base of the tongue contributes to retrusive movement of the tongue and that the genioglossus muscle contributes to protrusive movement. We also noted that this relationship between the activities of these two muscles were in response to postural changes during vowel productions without changes in the acoustic features. These findings suggest that these two muscles act not only antagonistically to produce retrusive and protrusive movement of the tongue, but also they complement each other to conserve the shape of the vocal tract for speech production. The functional relationship between these two muscles could contribute the consecutive movement of human speech production under various conditions and might be useful when applying rehabilitation approaches for the patients with neurological speech and swallowing disorders. 相似文献
72.
Kumiko Hattori Tetsuya Hattori Hiroshi Watanabe 《Probability Theory and Related Fields》1994,100(1):85-116
Summary Diffusion processes on the Sierpinski gasket and theabc-gaskets are constructed as limits of random walks. In terms of the associated renormalization group, the present method uses the inverse trajectories which converge to unstable fixed points corresponding to the random walks on one-dimensional chains. In particular, non-degenerate fixed points are unnecessary for the construction. A limit theorem related to the discrete-time multi-type non-stationary branching processes is applied. 相似文献
73.
Atomic beam-induced fluorination of polyimide and its application to site-selective Cu metallization
Tagawa M Maeda K Kajita T Yokota K Akamatsu K Nawafune H 《Langmuir : the ACS journal of surfaces and colloids》2007,23(23):11351-11354
Metallization methods of polyimide by hyperthermal atomic oxygen and atomic fluorine beams were developed. An atomic fluorine beam with a translational energy of 6.2 eV modified the wettability of polyimide surfaces to provide an advancing water contact angle of 132 degrees. It was confirmed that in-air storage for 2 months did not alter the hydrophobic property created by the atomic fluorine beam. This stable beam-induced surface fluorination technique was then applied to site-selective electroless Cu plating on polyimide. It was demonstrated that changing the exposure sequence could create both positive- and negative-type plating processes. 相似文献
74.
Ohno H Mizutani T Kadoh Y Aso A Miyamura K Fujii N Tanaka T 《The Journal of organic chemistry》2007,72(12):4378-4389
Thermal [2 + 2] cycloaddition of allenes with an additional multiple bond is described. By simply heating the allenenes or allenynes having a three-atom tether in an appropriate solvent such as dioxane or DMF, the distal double bond of the allenic moiety regioselectively participates in the cycloaddition to form bicyclo[4.2.0]oct-5-ene derivatives in good to excellent yields. In all the reactions of allenenes, the olefin geometry was completely transferred to the cycloadducts. While the reaction of terminal allenes afforded bicyclic cyclobutane derivatives as a single isomer, the cycloaddition of some internal allenes with axial chirality yielded a diastereomeric mixture of cycloadducts. These results are in good accordance with the stepwise mechanism through a biradical intermediate with a coplanar allyl radical. 相似文献
75.
Porous Carbon Fibers Containing Pores with Sizes Controlled at the Ångstrom Level by the Cavity Size of Pillar[6]arene 下载免费PDF全文
Dr. Tomoki Ogoshi Kumiko Yoshikoshi Ryuta Sueto Dr. Hirotomo Nishihara Prof. Tada‐aki Yamagishi 《Angewandte Chemie (International ed. in English)》2015,54(22):6466-6469
We report a new synthesis method of fibrous carbon material with pores sizes that are precisely controlled at the Ångstrom level, by carbonization of two dimensional (2D) porous sheets of pillar[6]arenes. The 2D porous sheets were prepared by 2D supramolecular polymerization induced by oxidation of hydroquinone units of pillar[6]arenes. Owing to the hexagonal structure of pillar[6]arene, the assembly induced by 2D supramolecular polymerization gave hexagonal 2D porous sheets, and the highly ordered structure of the 2D porous sheets formed regular fibrous structures. Then, carbonization of the 2D porous sheets afforded fibrous carbon materials with micropores. The micropore size of the fibrous porous carbon prepared from pillar[6]arene was the same size as that of the starting material pillar[6]arene assembly. 相似文献
76.
Inside Back Cover: Porous Carbon Fibers Containing Pores with Sizes Controlled at the Ångstrom Level by the Cavity Size of Pillar[6]arene (Angew. Chem. Int. Ed. 22/2015) 下载免费PDF全文
77.
Rapid and sensitive method for measuring the plasma concentration of doxorubicin and its metabolites
Doxorubicin is an anti-cancer drug with a wide therapeutic range. However, it and its metabolites cause severe side effects, limiting its clinical use. Therefore, measuring the plasma concentration of doxorubicin and its metabolites is important to study the dosing regimen of doxorubicin. We developed a rapid and sensitive method by ultra-high-performance liquid chromatography with fluorescent detection for measuring the plasma concentration of doxorubicin and its metabolites in small volumes (around 10?μL), enabling repeated measurements from the same mouse. The sensitivity of 7-deoxydoxorubicinolone, a major metabolite of doxorubicin, increased about 5 times than those ever reported using conventional HPLC, and the run time was within 3?min. The area under the curve (AUC0-24?h) of doxorubicin was 5.9?μg h/mL similar to the value of 4.16?μg?h/mL obtained previously using a conventional HPLC method. This method would provide information that could be used to refine the therapeutic approach to doxorubicin use. 相似文献
78.
Kiyama Akihito Endo Nanami Kawamoto Sennosuke Katsuta Chihiro Oida Kumiko Tanaka Akane Tagawa Yoshiyuki 《显形杂志》2019,22(3):449-457
Journal of Visualization - Realization of a needle-free drug delivery device can solve needle-caused problems. Recently, attention has been given to the use of a focused liquid jet instead of the... 相似文献
79.
Toru Amari Kumiko Nishimura Kimiko Minou Akira Kawabata Yukihiro Ozaki 《Journal of polymer science. Part A, Polymer chemistry》2001,39(5):665-674
End groups after the thermal degradation of poly(ethylene terephthalate) (PET) and its cyclohexanedimethanol (CHDM) copolymer were characterized with 1H NMR. Thermally degraded polymers were obtained by heat treatment at 290 °C. For the PET homopolymer, a vinyl end group appeared, which resulted from thermal cis‐β‐elimination. For the CHDM copolymer, in addition to a vinyl end group, methylcyclohexene and cyclovinylidene end groups originating from CHDM were formed. The assignment of the 1H NMR spectrum was performed with information from 13C NMR and gas chromatography‐mass spectrometry. The total amounts of unsaturated species measured by NMR were compared with those estimated by bromination titration. There was good agreement between the values obtained by the two methods, indicating that all the major unsaturated species were accounted for. The mechanism of the formation of the unsaturated end groups was investigated. We suggest, on the basis of the NMR measurements, that the methylcyclohexene and cyclovinylidene groups originating from CHDM were formed by thermal cis‐β‐elimination as for the PET homopolymer. © 2001 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 39: 665–674, 2001 相似文献
80.
A new glass capillary microelectrode for L-glutamate is described using pulled glass capillaries (tip size, approximately 12.5 microm) with a very small volume (approximately 2 microl) of inner solution containing glutamate oxidase (GluOx) and ascorbate oxidase. The operation of the electrode is based on capillary action that samples L-glutamate into the inner solution. The enzyme reaction by GluOx generates hydrogen peroxide that is detected at an Os-gel-HRP polymer modified Pt electrode in a three-electrode configuration. The amperometric response behavior of the electrode was characterized in terms of the capillarity, response time, sensitivity and selectivity for measurements of L-glutamate. The currents at 0 V vs. Ag/AgCl increased linearly with the L-glutamate concentration from 10 to 150 microM for in vitro and in situ calibrations. The response was highly selective to L-glutamate over ascorbate, dopamine, serotonin and other amino acids. The detection of L-glutamate in the extracellular fluids of different regions of mouse hippocampal slices under stimulation of KCl was demonstrated. 相似文献