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1.
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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Marek Behr 《国际流体数值方法杂志》2004,45(1):43-51
Hydrodynamic simulations of sloshing phenomena often involve the application of slip boundary condition at the wetted surfaces. If these surfaces are curved, the ambiguous nature of the normal vector in the discretized problem can interfere with the application of such a boundary condition. Even the use of consistent normal vectors, preferred from the point of view of conservation, does not assure good approximation of the continuum slip condition in the discrete problem, and non‐physical recirculating flow fields may be observed. As a remedy, we consider the Navier slip condition, and more successfully, the so‐called BC‐free boundary condition. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
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Barbara A. Bierl-Leonhardt Daniel S. Moreno Meyer Schwarz JoAn Fargerlund Jack R. Plimmer 《Tetrahedron letters》1981,22(5):389-392
The sex attractant pheromone of the citrus mealybug, (Risso), has been Identified as (1-)-(+)-2,2-dimethyl-3-(1-methylethenyl)cyclobutanemethanol acetate (VI). 相似文献
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The generalized inverse method is applied to the force constants calculation problem having a nearly singular Jacobian matrix, and by substituting it by one of lower rank which is near to it and well conditioned it is possible to eliminate the convergence difficulties of the least squares iteration process. A further significant advantage of the method is that certain matrix theoretical considerations give the possibility of deciding at the end of the iteration which force constants are determined by the available observations. Numerical results for the dimethylmercury molecule are given. 相似文献
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Mavis M. Kadooka Mildred Y. Chang Hiroshi Fukami P.J. Scheuer Jon Clardy Barbara A. Solheim James P. Springer 《Tetrahedron》1976,32(8):919-924
From the bark of the endemic Hawaiian tree Sophora chrysophylla Seem. we have isolated two unprecedented quainolizidine alkaloids, mamanine (4) and pohakuline (5). Both bases are 1-hydroxymethylenequinolizidines which are linked at C-3 to α-pyridone or α-piperidone moieties. The alkaloids may be intermediates in a heretofore unknown biogenetic pathway of Sophora alkaloids. 相似文献
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