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Acute and prolonged laryngitis commonly are diagnosed and treated by primary care physicians. These ailments come to the attention of the otolaryngologist when symptoms are prolonged despite treatment. Since the beginning of 1991, the senior authors (RTS, JRS) have recognized a clinical syndrome defined by prolonged hoarseness, prolonged laryngeal inflammation, and vocal fold ulceration. Patients are frequently young, nonsmokers, and nondrinkers who have had an upper respiratory infection prior to, or associated with, the onset of laryngeal symptomatology. Patients may be affected for up to 1 year despite aggressive medical therapy. This review of 14 patients highlights the features of this previously undescribed entity.  相似文献   
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Helicobacter pylori (HP) is an accepted cause of chronic active gastritis and has a major causative role in peptic ulcers. It is a gastric carcinogen. Its role in nonulcer dyspepsia (NUD) is less clear, yet 50% of patients with NUD are infected with HP, and some recent literature demonstrates long-term improvement of symptoms following eradication. HP has been investigated in several other organ systems, but has not been investigated to any major degree in laryngeal disorders, a region that could be directly exposed to the bacterium from pharyngolaryngeal reflux. This study represents one arm of a larger study designed to investigate such a relationship. Of 101 patients with nonmalignant voice disorders presenting to our voice clinics, 54.5% tested positive for the H. pylori organism. Of the controls, 47.1% tested positive. When striated into age groups of < 45 years, 46–61 years, and > 62 years, and then age-matched with the controls, the likelihood of infection with the H. pylori organism was greater in both the experimental middle group, and in the middle group when combined with the elder group, than in the matched controls, and this difference demonstrated a trend approaching statistical significance. This finding is discussed in the light of other studies on HP and on gastroesophageal reflex (GER).  相似文献   
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Laryngeal Chondroma   总被引:3,自引:0,他引:3  
Cartilaginous tumors of the larynx represent less than 1% of laryngeal tumors. Chondroma and "low-grade" chondrosarcoma are the most common; 70%-75% of these tumors arise on the endolaryngeal surface of the posterior lamina of the cricoid cartilage. The clinical presentation is varied and directly dependent on the size and location of the tumor; stridor, hoarseness, dyspnea, or a neck mass are common presenting signs. CT scanning in the axial plane is the mainstay of radiographic imaging due to its ability to show size, extent of the tumor, and invasion into surrounding structures. Surgical extirpation is the standard therapy with no role for radiation therapy or chemotherapy. Although significant recurrence rates have been reported, there is not a significant difference between initial conservative therapy followed by salvage therapy versus initial radical therapy.  相似文献   
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A magnetized Iron CALorimeter (ICAL) detector at the India-based neutrino observatory (INO) is used to study neutrino oscillation sensitivity using atmospheric muon neutrino source. The ICAL detector will be able to detect muon tracks and hadron showers produced by neutrino interactions with the iron target. We have performed precision measurement analysis for the atmospheric neutrino oscillation parameters with the muon neutrino events, generated by Monte Carlo NUANCE event generator. A marginalized χ2 analysis based on reconstructed neutrino energy and muon zenith angle binning scheme has been performed to determine the sensitivity for the atmospheric neutrino mixing parameters, \(\sin ^{2}\theta _{23}\) and \(| {\Delta } m^{2}_{23}|\).  相似文献   
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Characterization of chronic vocal fold scarring in a rabbit model   总被引:2,自引:0,他引:2  
The purpose of the current study was to assess the histologic and rheologic properties of the scarred vocal fold lamina propria during a chronic phase of wound repair in a rabbit model. Eighteen rabbit larynges were scarred using a procedure that involved stripping the vocal fold lamina propria down to the thyroarytenoid muscle, using 3-mm microforceps. The approximate dimension of injury to the vocal fold was 3 x 1.5 x 0.5 mm [length x width x depth]. At 6 months postoperatively, histologic analysis of the scarred and control lamina propria in eight of these rabbits was completed for collagen, procollagen, elastin, and hyaluronic acid. Compared with control samples, scarred tissue samples revealed fragmented and disorganized elastin fibers. Additionally, collagen was significantly increased, organized, and formed thick bundles in the scarred vocal fold lamina propria. Measurements of the viscoelastic shear properties of the scarred and control lamina propria in the remaining 10 rabbits revealed increased elastic shear modulus (G') in 8 of 10 scarred samples and increased dynamic viscosity (eta') in 9 of 10 scarred samples. Although rheologic differences were not statistically significant, they revealed that on average, scarred samples were stiffer and more viscous than the normal controls. Histologic data are interpreted as indicating that by 6 months postinjury, the scarred rabbit vocal fold has reached a mature phase of wound repair, characterized by an increased, organized, and thick bundle collagen matrix. Rheologic data are interpreted as providing support for the potential role of increased, thick bundle collagen, and a disorganized elastin network on shear stiffness and dynamic viscosity in the chronic vocal fold scar. Based on these results, a 6-month postoperative time frame is proposed for future studies of chronic vocal fold scarring using the rabbit animal model.  相似文献   
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The use of a highly aligned carbon nanotube (CNT) sheet as a multifunctional constituent for liquid crystal (LC) displays and electro-optic LC applications is assessed. The CNT sheet can perform a dual function: one is an alignment layer for LCs, replacing the commonly used rubbed polyimide film, and the other is a transparent conductive layer, taking the place of indium tin oxide. The hydrophobic treatment improved the adhesion quality between aligned CNT bundles and the glass substrate, which helps to preserve the inherently aligned nanogroove morphology of transparent CNT sheets. The test LC display cells, comprising 4-cyano-4′-pentylbiphenyl molecules sandwiched between CNT-sheet-on-glass substrates, demonstrate the operation characteristics comparable to that of the conventional cell under temperature variation and ac electric field of 1?kHz. The results offer a possibility of deploying multifunctional CNT-sheet alignment layers in LC-based devices, especially in the future flexible display applications.  相似文献   
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We describe a simple means of assessing the condition of the superficial lamina propria during endoscopy, which we use in our practice as an adjunct to careful stroboscopic examination. An intake of breath against partially adducted vocal folds serves to draw the mucosa inferomedially into the glottis, which reveals areas of diminished mobility, the relationship of mucosal lesions to deeper tissues of the vocal folds, and subtle submucosal lesions. This is possible because of the unique geometry of the glottis that renders the vector forces of airflow different at inspiration and expiration. Because the integrity of the superficial lamina propria is essential to healthy phonation, we have found the inspiratory maneuver useful across a wide variety of mucosal pathologic conditions.  相似文献   
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