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New insights into the anatomy and physiology of phonation, along with technological advances in voice assessment and quantification, have led to dramatic improvements in medical voice care. Techniques to prevent vocal fold scar have been among the most important, especially scarring and hoarseness associated with voice surgery. Nevertheless, dysphonia due to vocal fold scar is still encountered all too frequently. Although it is not generally possible to restore such injured voices to normal, patients with scar-induced dysphonia can usually be helped. Voice improvement is optimized through a team approach. Treatment may include sophisticated voice therapy and vocal fold surgery. Although experience with collagen injection has been encouraging in selected cases (particularly in those involving limited areas of vocal fold scar), there is no consistently successful surgical technique. Attempts to treat massive vocal fold scar, such as may be seen following vocal fold stripping, have been particularly unsuccessful. This paper reports preliminary experience with the implantation of autologous fat into the vibratory margin of the vocal fold of patients with severe, extensive scarring. Using this technique, it appears possible to recreate a mucosal wave and improve voice quality. Additional research is needed.  相似文献   
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Symptoms of unilateral vocal fold paralysis are improved significantly by augmenting the paralyzed vocal fold via vocal fold injection. In this trial, augmentation with a new calcium hydroxylapatite implant was evaluated. In addition, two different phonosurgical injection techniques were used, and these procedures were compared for accuracy and reliability. A total of 11 terminal patients with unilateral vocal fold paralysis underwent vocal fold injection with calcium hydroxylapatite. Efficacy of the implant was evaluated by comparing results from the Voice Handicap Index (VHI) and mean airflow measurements before and 6 months after injection. Surgeon evaluations determined the comparative benefits of either endoscopic direct vocal fold injection or percutaneous vocal fold injection. Six-month data were obtained for a cohort of five patients. VHI scores improved for all five patients available for full evaluation and four of the five achieved improvements in mean airflow rates. Of the remaining patients, one later had a medialization laryngoplasty, two died from their terminal diseases before the 6-month follow-up, and two of the remaining three reported satisfaction with the results via telephone follow-up. Vocal fold injection via endoscopic, direct laryngoscopy was found to be a more reliable procedure for vocal fold injection than percutaneous injection. Slight overinjection (10% to 15%) was found to provide optimum results. Vocal fold injection of calcium hydroxylapatite for unilateral vocal fold paralysis improved voice quality and reduced mean airflow rates in this patient group with short-term results. Long-term studies are needed to confirm the durability of these findings.  相似文献   
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The pressure dependence of the Young's and shear moduli of RFe2 (R = Sm, Gd, Tb, Dy, Ho and Er) has been determined at room temperature in the pressure range between 0 and 1 GPa The elastic moduli of GdFe2, DyFe2, HoFe2 and ErFe2 show a moderate increase with increasing hydrostatic pressure However, the elastic moduli of SmFe2 and TbFe2 exhibit an initially drastic increase followed by a high, and linear, pressure dependence From the pressure and temperature derivatives of the elastic moduli of these RFe2 Laves phase compounds the equations of state and the Gruneisen parameters have been derived The variation of the elastic properties with hydrostatic pressure is compared with the effect of magnetic fields The anomalous behavior of SmFe2 and TbFe2 is discussed.  相似文献   
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It is observed that the magnitude relationma 2 l P/c holds if the non-Euclidean incremental spatial volume associated with a fundamental particle of massm and radiusa is characteristically quantum gravitational in a Kaluza-Klein or superstringR 4×K N . HereR 4 is the four-dimensional Riemannian space-time of general relativity andK N is a small-scale, compact,N-dimensional space of characteristic quantum gravitational volumel P N , withl P (G/c 3)1/2= 1.61×10–33 cm denoting the Planck length. For the electron and electron neutrino (assumed to possess nonzero mass bounded empirically by <30 eV) the derived magnitude relationa(l P/mc)1/2 yields the estimatesa e 2.5×10–22 cm and 3.3×10–20 cm, spatial extensions which may be detectable by way of fine-scale effects in SSC experiments.  相似文献   
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Analyzing mass spectrometry imaging data can be laborious and time consuming, and as the size and complexity of datasets grow, so does the need for robust automated processing methods. We here present a method for comprehensive, semi-targeted discovery of molecular distributions of interest from mass spectrometry imaging data, using widely available image similarity scoring algorithms to rank images by spatial correlation. A fast and powerful batch search method using a MATLAB implementation of structural similarity (SSIM) index scoring with a pre-selected reference distribution is demonstrated for two sample imaging datasets, a plant metabolite study using Artemisia annua leaf, and a drug distribution study using maraviroc-dosed macaque tissue.
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