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101.
102.
A study was made of the prevalence of voice disorders and their risk factors in teaching professionals of Logro?o, Spain. A prevalence and case-control study was made, including interviews, ENT examination, videostrobolaryngoscopy, perceptual evaluation of hoarseness, basic aerodynamic tests, the physical range of phonation, and a physical analysis of the acoustic signal. The prevalence of voice disorders among Logro?o teachers was 17.7% (confidence interval: 12.1-25%). Nodular lesions (8.1%) were the most frequent pathology, followed by hyperfunctional dysphonia (4.1%), chronic laryngitis (2.7%), polyps (1.4%), hypofunctional dysphonia (0.7%), and submucous suffusion (0.7%). Voice disorders were more prevalent in women (19.3%) than in men (15.6%), and among teachers of the lowest grades: 36.4% in nursery schools, 25% in elementary school, and 20.8% in junior school. The width and depth of classrooms, larger number of students, longer classroom hours, and noise level were related with the frequency of voice disorders. 相似文献
103.
A co‐polyester liquid crystalline polymer (LCP) was melt blended with an acrylonitrile–butadiene–styrene copolymer (ABS). LCP fibrils are formed and a distinct skin/core morphology is observed in the injection moulded samples. At higher LCP concentration (50 wt%), phase inversion occurs, where the dispersed LCP phase becomes a co‐continuous phase. While the tensile strength and Young's modulus remain unchanged with increasing LCP content up to 30 wt% LCP, a significant enhancement of the modulus at 50 wt% LCP is observed due to the formation of co‐continuous morphology. The blend modulus is lower than the values predicted by the rule of mixtures, suggesting a poor interface between the LCP droplets and ABS matrix. A copolymer of styrene and maleic anhydride (SMA) was added in the LCP/ABS blends during melt blending. It is observed that SMA has a compatibilizing effect on the blend system and an optimum SMA content exists for mechanical properties enhancement. SMA improves the interfacial adhesion, whereas excess of SMA reduces the LCP fibrillation. Copyright © 2003 Society of Chemical Industry 相似文献
104.
WL Hutton DG Fuller WB Snyder RL Fellman WH Swanson 《Canadian Metallurgical Quarterly》1996,103(12):2152-8; discussion 2158-9
PURPOSE: The purpose of the study is to report the problem of a temporal visual field defect occurring after macular hole surgery. METHODS: The authors reviewed the records of 13 patients found to have visual field defects after vitrectomy for macular holes. Fluorescein angiograms (13 patients), optic nerve photographs (13 patients), focal electroretinograms (3 patients), and nerve fiber analyses (8 patients) were performed in patients with visual field defects. RESULTS: An absolute, temporal, usually inferior field defect was noted in 13 patients. In eight patients, the defect was detected because of specific reports or retrospective field examination results. Five patients examined in a prospective manner were found to have field defects. No history of abnormal intraocular pressure or direct trauma to the optic nerve or retinal vessels was identified. Four patients showed optic nerve pallor and three had an anomalous-appearing disc. Focal electroretinograms were of similar amplitude in the involved retina compared to corresponding areas in the healthy fellow eye. Nerve fiber analysis showed a reduction in nerve fiber layer thickness correlating to the visual field defect in those eight patients in which this test was used. CONCLUSION: A significant temporal field defect may occur in patients after otherwise uncomplicated surgery for macular holes. The cause is unclear; however, reductions in nerve fiber layer thickness from the superior and nasal peripapillary area suggest that acute surgical release of the posterior hyaloid and the use of long-acting intraocular gas may in certain patients result in visual field defects. 相似文献
105.
106.
Micrometer-sized domains of a carbon surface are modified to allow derivatization to attach redox enzymes with biotin/avidin technology. These sites are spatially segregated from and directly adjacent to electron transfer sites on the same electrode surface. The distance between these electron transfer sites and enzyme-loaded domains must be kept to a minimum (e.g., less than 5 microns) to maintain the fast response time and high sensitivity required for the measurement of neurotransmitter dynamics. This is accomplished through the use of photolithographic attachment of photobiotin using an interference pattern from a UV laser generated at the electrode surface. This will allow the construction of microscopic arrays of active enzyme sites on a carbon fiber substrate while leaving other sites underivatized to facilitate electron transfer reactions of redox mediators, thus maximizing enzyme activity and detection of the enzyme mediator. The ultimate sensitivity of these sensors will be realized only through careful characterization of the carbon electrode surface with respect to its chemical structure and electron transfer properties following each step of the enzyme immobilization process. The characterization of specific modifications of micrometer regions of the carbon surface requires analytical methodology that has both high spatial resolution and sensitivity. We have used fluorescence microscopy with a cooled CCD imaging system to visualize the spatial distribution of enzyme immobilization sites (indicated by fluorescence from Texas Red-labeled avidin) across the carbon surface. The viability of the enzyme attached to the surface in this manner was demonstrated by imaging the distribution of an insoluble, fluorescent product. An atomic force microscope was used to obtain high-resolution images that probe the heterogeneity of the enzyme sites. 相似文献
107.
108.
Summary A nonlinear boundary-value problem for the equilibrium of a pressurized magnetoelastic membrane acted upon by an applied magnetic
field is derived from three-dimensional magnetoelasticity. The model is specified entirely by differential equations in the
limit of weak material magnetization, these replacing the integro-differential equations of the general theory. The model
is further specialized to axisymmetry, and several problems of technical interest are solved numerically. 相似文献
109.
A Brashear D DeLeon SB Bressman D Thyagarajan MR Farlow WB Dobyns 《Canadian Metallurgical Quarterly》1997,48(4):1066-1069
Rapid-onset dystonia-parkinsonism (RDP), first described in a large Midwestern family, is now reported in a second, apparently unrelated, family in which four individuals have this same syndrome. All four developed sudden onset of dysarthria, dysphagia, severe dystonic spasms, bradykinesia, and postural instability over less than 1 hour to a few days. Three of the four had stable limb dystonia for several years preceding the onset of combined dystonia-parkinsonism. Treatment with levodopa/carbidopa provided little benefit. We propose diagnostic criteria for RDP and further define the spectrum of this unusual disease. 相似文献
110.
WB Stiles R Agnew-Davies GE Hardy M Barkham DA Shapiro 《Canadian Metallurgical Quarterly》1998,66(5):791-802
Clients (n = 79) and therapists (n = 5) rated their alliance using parallel forms of the Agnew Relationship Measure (ARM) after every session of their time-limited psychodynamic-interpersonal or cognitive-behavioral treatments for depression. The ARM assesses 5 dimensions of the alliance: Bond, Partnership, Confidence, Openness, and Client Initiative. Treatment outcome was assessed as residual gain from pretreatment assessment to end of treatment, 3-month follow-up, and 1-year follow-up on 6 standard measures. Some aspects of the alliance as measured by the ARM were correlated with clients' gains in treatment. The strength of the association varied across assessment measures, occasions of outcome assessment, ARM scales, and the session number when the alliance was measured. 相似文献