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41.
The objective of this study was to examine the vocal symptoms and acoustic changes perceived in the short period after endotracheal intubation, and to find the association between these changes and the endotracheal tube parameters. A total of 35 subjects were included. They were examined preoperatively, and 2 and 24 hours postoperatively. The vocal symptoms of hoarseness, vocal fatigue, loss of voice, throat clearing, globus pharyngeus, throat pain, and the acoustic variables mainly average fundamental frequency, relative average perturbation, shimmer, noise to harmony ratio, voice turbulence index, habitual pitch, and maximum phonation time (MPT) were assessed as such and in relation to the following endotracheal tube parameters: duration of anesthesia, number of intubation attempts, size of the tube, cuff volume, cuff mean pressure, and the emergence. The association between anesthesia parameters with incidence of vocal complaints and changes in acoustic parameters were examined using logistic and linear regression. Vocal fatigue was associated significantly with the increase in cuff volume and the number of intubation attempts. Throat clearing was associated significantly with the increase in cuff mean pressure. Only the increase in habitual pitch was associated significantly with the increase in cuff volume. The acute short-term effect of endotracheal intubation on voice is significant. The most important endotracheal tube parameters that affect the vocal changes are the cuff mean pressure and volume. The laryngeal contribution to these vocal changes seems to be minimal. All vocal symptoms increased significantly except for globus pharyngeus at 2 hours postoperatively. The acoustic parameters did not change significantly except for a decrease in MPT. At 24 hours postoperatively, all vocal symptoms subsided with no significant difference to baseline value. The habitual pitch increased significantly, and the rest of the parameters remained comparable to baseline value. 相似文献
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Summary A pattern recognition methodology has been developed for analysis of chromatographic data. The method uses a new class of
multidimensional orthogonal polynomials developed by Cohen in conjunction with a supervised learning technique. The method
is applicable to any chromatographic data for which classification into two or more categories is desired. The algorithm analyzes
both elution times and peak areas. An application is shown for the analysis of organic acids in ascitic fluid obtained from
patients with liver disorders. Classification of these patients for presence or absence of bacterial infection shows over
ninety percent correct classification. 相似文献
45.
Prader-Willi syndrome (PWS) is a multisystem disorder caused by DNA abnormalities involving chromosome 15. Major characteristics are infant hypotonia, hypogonadism, mental retardation, a short stature, atypical facial appearance, and the onset of obesity due to insatiable hunger in early childhood. Also, speech and language abnormalities have been reported including voice disorders. These have seldom been studied in detail, however. This paper reports the results of an acoustic and aerodynamic investigation of the voice in 22 individuals with PWS. Two age groups were distinguished, a group of children [chronological age (CA) 6 years, 7 months through 11 years, 7 months; total intelligence quotient (TIQ) 40-88] and a group of adolescents and adults (CA 17 years, 1 month through 29 years, 5 months; TIQ 41-94). Both aerodynamic and acoustic parameters were obtained and compared with normative data from the Belgian Study Group on Voice Disorders. It was found that voice difficulties do commonly occur in individuals with PWS including impairment of frequency levels, voice quality, and poor aerodynamic capabilities. 相似文献
46.
N.S. Jones F.J. Lannigan M. McCullagh A. Anggiansah W. Owen T.M. Harris 《Journal of voice》1990,4(4):355-358
The aim of this study was to investigate the prevalence of acid reflux in patients complaining of hoarseness where no organic disease or functional dysphonia could be found. We also aimed to determine whether anti-reflux treatment improved their symptoms. Patients were not selected on the basis of symptoms of reflux. Fifty patients with hoarseness took part in a prospective study that sought to establish objectively whether acid reflux was present. All patients were given a 6-week course of ranitidine and Gaviscon. Patients were asked to score their voice quality before and after treatment. Although 72% of patients complained of heartburn more than once a week, only 40% proved to have acid reflux. Although subjective improvement after anti-reflux treatment was found in a larger proportion of those with than without proven reflux, the conclusions that can be drawn are limited as there were no satisfactory objective measurements of voice or controls. 相似文献
47.
The surgical management of bilateral vocal cord paralysis has been performed through an endoscope in the past. The etiology of bilateral vocal cord paralysis is usually secondary to trauma; to secure an adequate airway, a tracheostomy is performed. Endoscopic laser arytenoidectomy offers a safe method of decannulating patients with maintenance of good voice quality and a rima glottidis of 4–6 mm posteriorly. Several wavelengths are available to carry out this procedure, and this article will focus on Nd:Yag laser scalpel applications. The advantage of this method is the preservation of good voice quality with an option of an external procedure, if the need arises. The laser application offers excellent hemostasis, and decreased edema and scar tissue formation. The results of our study on 10 patients appear encouraging and superior with respect to other available wavelengths. 相似文献
48.
Wojtowicz P Zrostlíková J Kovalczuk T Schůrek J Adam T 《Journal of chromatography. A》2010,1217(51):8054-8061
Organic acidurias are a large group of inherited metabolic disorders (IMDs), commonly diagnosed by GC-MS analysis of organic acids in urine after acidic extraction and trimethylsilylation. In this study, a GC×GC-ToF-MS method has been optimized for the analysis of pathological metabolites in urine. An automated data processing strategy based on the use of mass spectra and GC retention times for the target search and quantification of pathological metabolites has been developed. Using this procedure, each unknown sample is automatically examined for the presence of markers of several diseases at the same time. The method has been applied for the analysis of 6 challenging proficiency testing samples from patients with IMDs (thymidine phosphorylase deficiency, mevalonic aciduria, hawkinsinuria, aromatic l-amino acid decarboxylase deficiency, propionic acidemia and medium-chain acyl-CoA dehydrogenase deficiency). Using the GC×GC-ToF-MS method, we were able to determine complete sets of markers for all the IMDs. The quality of the mass spectral matches for the pathological markers was higher than 800 (out of 1000). 相似文献
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Maysa Tibério Ubrig Maria Valéria S. Goffi-Gomez Raimar Weber Márcia H. Moreira Menezes Nair Kátia Nemr Domingos Hiroshi Tsuji Robinson Koji Tsuji 《Journal of voice》2011,25(6):692-699