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951.
A combined-modality treatment program consisting of botulinum toxin injection (Botox) and voice therapy was used to treat 17 subjects diagnosed with adductor spasmodic dysphonia (ADD SD). Ten subjects with ADD SD served as the control and were given Botox only. Voice therapy after Botox injection was directed toward reducing the hyperfunctional vocal behaviors, primarily glottal overpressure at voice onset and anterior-posterior squeezing. The results indicated that subjects who underwent combined-modality treatment maintained significantly higher mean airflow rates for significantly longer periods. Moreover, there was a carryover effect in these patients when they received Botox only. Adductor spasmodic dysphonia is treated most effectively when intrinsic laryngeal muscle spasms are reduced or eliminated by Botox injection and extrinsic hyperfunctional vocal behaviors are treated with voice therapy 相似文献
952.
953.
元素在石墨炉内石墨探针表面上的原子化机理研究:Ⅶ.锗的原子化机理 总被引:2,自引:0,他引:2
本文应用X-射线衍射,X-射线光电子能谱,俄歇电子能谱和其它一些实验,考察石墨炉升温过程中氟化锗,锗酸钠在石墨探针表面上的形态变化,阐明了它们的原子化机理:GeF2与Na2GeO3首先分解为GeO2,GeO2还原为GeO,后者在>2400K热分解产生自由态的锗原子,GeF2和Na2GeO3的原子化均源于GeO(g)的气相分解。原子化的升温过程中,在1400-2400K GeF2和Na2GeO3都产 相似文献
954.
The determination of the enantiomeric purity of 2 or 3-substituted cyclanones, particularly cyclohexanones, is conveniently achieved by derivatisation into cyclic aminals with commercially available (R, R)-1,2-diphenylethylenediamine. The derivatisation procedure is directly done into the NMR tube, instantaneously, and 13C NMR allows an accurate measure of the ee. 相似文献
955.
The activity coefficients of NaBr in the NaBr–NaPropionate–H2O and NaBr–NaButyrate–H2O systems were determined from EMF measurements at constant total ionic strength of 0.1 0.5 1.0 1.5 2.0 and 2.5 mol-kg–1 and at 25° C. The activity coefficients were fitted using Scatchard, Pitzer and Lim equations. Finally the excess Gibbs free energy of these mixtures were also calculated. 相似文献
956.
Y. Yamamoto H. Kidooka Y. Honda S. Yasuda 《International Journal of Infrared and Millimeter Waves》1995,16(3):579-589
A novel method using small neon glow lamps with electrodes is developed for measuring intense microwave field patterns. When the lamp axis coincide with the electric field direction, the lamp discharge starts at the feeblest microwave electric field strength. Therefore, the lamp axis shows the field direction and the discharge starting indicates the field strength. The field strength for starting the microwave discharge is less than the strength for AC discharge, because of its low loss discharge mechanism. In the experiments using a microwave oven, it has been demonstrated again comparing with the simulated results that the method is able to use for measuring the intense electric field strength and direction. 相似文献
957.
V. L. Bratman G. G. Denisov A. V. Savilov 《International Journal of Infrared and Millimeter Waves》1995,16(3):459-471
A relatively high level of the minimal electron energy at the gyrotron output even at very large spread in pitch factor is explained. An estimation of the recuperation efficiency, which can be obtained due to this effect, is given. 相似文献
958.
单模光纤中皮秒啁啾脉冲压缩 总被引:11,自引:2,他引:9
对单模光纤正群速色散区秒啁啾脉冲的非线性传进行了近似的解析分析和定量的数值计算。结果表明,负啁啾脉冲在传输过程中能得到有效压缩。压缩比与脉冲初始峰值功率和初始啁啾程度有关。初始峰值功率一定的脉冲,其压缩比随初始啁啾程度的增大面大,初始啁啾程度一定的脉冲,压缩比随初始峰值功率的增大而减小,表明自相位调制效应导致脉冲压缩效果变差。计算结果还表明,在脉冲时域宽度得到压缩的同时,光谱宽度也能得到同步压缩。 相似文献
959.
火焰原子吸收光谱法测定磁化杯中铅、镉和铁 总被引:1,自引:0,他引:1
本文研究了火焰原子吸收光谱法测定磁化杯陶瓷内胆中Ph、Cd和Fe含量的方法。样品经粉碎,用硝酸-高氯酸混合液进行消解后测定。本法灵敏度高,干扰少,简单,快速,具有良好的精密度和准确度,其相对标准偏差分别为Pb3.99%,Cd10.7%,Fe0.9%。回收率Pb100.61%,Cd101.18%,Fe102.4%。 相似文献
960.
I. I. Antakov E. V. Zasypkin E. V. Sokolov 《International Journal of Infrared and Millimeter Waves》1993,14(5):1001-1015
Formulas for shifts of gyrotron autooscillation frequency due to change of electron beam parameters are presented. The frequency shifts can be commensurable with the frequency band of the beam-unloaded cavity. The autooscillation frequency is most sensitive to the change of the magnetic field, less to the change of the anode voltage and least to the the change of the beam voltage. Experiments presented are in satisfactory agreement with the theory.The authors wish to thank M.I. Petelin for his interest to the present work. 相似文献