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Susan Baker Lisa Kelchner Barbara Weinrich Linda Lee Paul Willging Robin Cotton Karen Zur 《Journal of voice》2006,20(4):631-641
Laryngotracheal stenosis is defined as a congenital or acquired narrowing of the airway. Congenital causes may include subglottic membranous or cartilaginous narrowing. Acquired causes may include trauma due to prolonged endotracheal or tracheal intubation or laryngotracheal injury. Although advances have been made over the past 30 years in reconstructive surgeries to improve airway patency in these patients, long-term laryngeal function for voice production is not well defined in this population. This review examines causes, symptoms and signs, and methods for diagnosing laryngotracheal stenosis. Surgical management procedures are briefly summarized. The current literature on voice outcomes is summarized. The predominant voice characteristics in the population are presented, although results are challenged by the heterogeneity of voice presentation and paucity of data from instrumental measures. Considerations for subjective and instrumental assessment, measures of quality of life, instrumental methods, and treatment options specific to the needs of this population are discussed. Research strategies to identify long-term outcomes of surgical and behavioral treatments in this population are posed. 相似文献
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S. B. Ellis S. J. Kiehl W. S. Hughes K. Schwabe W. C. Gardiner H. L. Sanders H. Yoshimura Hanna Jablezynska-Jedrzewska J. Domański W. A. Dorfman P. Nylén Barbara Stone F. Hovorka W. C. Dearing E. Biilmann W. Kordatzki P. Wulff G. Florence A. Drilhon P. Szigeti O. Tomiček F. Poupě O. Redlich W. Stricks 《Analytical and bioanalytical chemistry》1937,111(2-4):94-104
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Sébastien Lemaire Giuliano Giambastiani Barbara Pacini Giovanni Poli 《Journal of organometallic chemistry》2003,687(2):291-300
A new type I palladium-catalyzed pseudo-domino process is developed, in which a single Pd-based catalytic system promotes two mechanistically unrelated, sequential catalytic cycles in chronologically distinct order. Suitable precursors undergo an allylic alkylation and a Heck coupling in sequence, affording polycondensed pyrrolidone derivatives. Depending on the starting precursors, intra/inter or doubly intramolecular processes can be obtained. The allylic alkylation process takes place always very smoothly. On the other hand, the Heck coupling turns out to be rather difficult either when the process is intermolecular, or when an intramolecular process generates polycondensed structures featuring three fused bonds connected to a common carbon atom. In such difficult cases, use of the Herrmann-Beller phosphapalladacycle allowed to catalyze the coupling. This study demonstrates also that allylic alkylations can be catalyzed by the Herrmann-Beller phosphapalladacycle. 相似文献
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E.Ann Hallinan Clifford R. DornWilliam M. Moore Gina M. JeromePamela T. Manning Barnett S. Pitzele 《Tetrahedron letters》2003,44(39):7345-7347
Described is a method of introducing trifluoroalkyl groups at C-6 of lysine. This chemistry has the potential to introduce a variety of functionality at C-6 of lysine. 相似文献
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Vishal Sipani Ann Kirsch Alec B. Scranton 《Journal of polymer science. Part A, Polymer chemistry》2004,42(17):4409-4416
The effective propagation rate constant (kp; averaged over all the propagating active centers) was characterized for solvent‐free cationic photopolymerizations of phenyl glycidyl ether over the entire range of conversions, including the high conversion regime in which mass transfer limitations become important. The profile for the kp as a function of conversion was found to exhibit a constant plateau value at low to intermediate conversions, followed by a monotonic increase above a threshold value of conversion. To explain this trend, it is proposed that at high conversion the diffusional mobility of the photoinitiator counterion is reduced whereas the mobility of the cationic active center remains high because of reactive diffusion. Therefore, with increasing conversion, the average distance between the active centers and counterions may increase, resulting in an increase in the propagation rate constant. The profiles for the kp values were investigated as a function of the temperature, photoinitiator anion, and photoinitiator concentration. As the photoinitiator concentration was increased, the plateau value of the effective propagation rate constant decreased whereas the threshold conversion increased. All of the experimental trends are consistent with the proposed increase in ion separation at high conversions. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 4409–4416, 2004 相似文献
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