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91.
The Auditec recordings of the CID W-22 monosyllables were used to generate test and retest intelligibility functions on normally hearing listeners and subjects with mild-to-moderate sensorineural hearing loss. The normally hearing subjects were tested with 50-word lists at SPLs ranging from 15 to 50 dB. Lists of 25 words were used with the hearing-impaired group. The functions were analyzed to assess the reliability of threshold (50% point), slope (20%-80% points), and maximum intelligibility (PB max). The 50% point was obtained at 28 dB SPL for the normally hearing listeners and at a sensation level (SL) of 12 dB respondaic thresholds for the hearing-impaired group. Very stable monosyllabic thresholds were found because 95% of the test-retest values were within 6 dB for both subject groups. Slopes of 4.9% per dB and 2.7% per dB were obtained for the normally hearing and hearing-impaired groups, respectively. Fair reliability was observed; 95% of the test-retest values encompassed a range of +/- 1.9% per dB for the normally hearing subjects and +/- 1.1% per dB for the hearing-impaired group. Although group slopes provide useful information for selecting the range and step size for generating psychometric functions, the value of routinely obtaining slope on an individual basis has not been demonstrated. Even though the same word lists were used for both test and retest measurements, reliability closely agreed with predicted results based on the binomial theorem. In contrast to the large variability for a single list of 25 words, very stable PB max scores were found when two or three scores were averaged on the plateau of the function. 相似文献
92.
R C Beattie 《Scandinavian audiology》1988,17(2):99-109
The present study investigated the interaction of click polarity (compression, rarefaction, alternating), repetition rate (2.3 and 9.2 clicks per second), and stimulus level (60, 75, and 90 dB nHL) on auditory brainstem responses. Two tracings (trials) were obtained for each condition using 45 normally hearing subjects. Although no systematic Wave I, III, or V latency or amplitude differences were observed among polarities or repetition rates at the three intensities, statistically significant differences were observed for the following conditions: (1) Wave III latency at 90 dB nHL was longer for the 9.2 repetition rate than for the 2.3 rate, and latencies for compression clicks were shorter than rarefaction clicks; (2) Wave V latencies at 75 dB nHL were longer with compression clicks than with rarefaction clicks; (3) mean Wave V latencies at 60 and 75 dB nHL were slightly longer for the 2.3 click rate than for the 9.2 rate; and (4) Wave V amplitudes at 90 dB nHL were larger for rarefaction clicks than for compression clicks. Because latency and amplitude differences were small and only found in a few conditions, the results indicate that polarity is not a significant variable in normally hearing subjects when using slow repetition rates (less than or equal to 10 clicks per second) at moderate to high intensities (60 to 90 dB nHL). Because repetition rates of less than 10 clicks per second increases examination time but does not improve wave morphology, rates of 10 per second or faster are recommended for gathering normative data. Absolute amplitudes showed considerable intersubject variability, especially for Waves I and III. Intrasubject variability (test-retest) also was substantial. These findings suggest that absolute amplitudes may be of little use for distinguishing normal from pathologic populations. 相似文献
93.
R C Beattie F E Beguwala D M Mills R L Boyd 《The Journal of speech and hearing disorders》1986,51(1):63-70
This study examined the effects of electrode placement on the early auditory evoked response in normally hearing subjects. The electrodes are termed noninverting, inverting, and common. Ten commonly used electrode combinations were evaluated. Both amplitudes and latencies of Waves I, III, and V were measured for each electrode combination. No mean differences in latencies were observed for Waves I, III, or V with any of the 10 electrode combinations. Similarly, no statistically significant Wave I or Wave III amplitude differences were found among the 10 electrode montages. However, larger Wave V amplitudes were found with placement of the noninverting electrode at the vertex (0.53 mu v) as compared to the upper forehead (0.39 mu v). Moreover, Wave V amplitudes were larger for inverting/common electrode placements at the seventh cervical vertebra/forehead, neck/forehead, and neck/neck (approximately 0.50 mu v) than for mastoid/mastoid and mastoid/forehead placements (approximately 0.40 mu v). Thus, three combinations of electrodes gave the largest Wave V amplitudes. These placements for the noninverting, inverting, and common electrodes, respectively, were (a) vertex-seventh-forehead, (b) vertex-neck-forehead, and (c) vertex-neck-neck. 相似文献
94.
The effect of S/N from +20 to -10 db on loudness levels of connected discourse with or without background cafeteria noise was investigated for one set of instructions sampling the most comfortable loudness level (MCLL) and a second set sampling the upper limit of CLL. Normal young adults (N:16) showed no significant differences for either set of instructions in quiet or from 20 to 0 db S/N but mn MCLL was about 5 db lower at -10 db. Elderly hearing-aid wearers (N:10, mn age: 77 yrs) yielded mn differences across S/N of less than 5 db for either set of instructions. No data indicate that the speech CLL accurately predicts optimal hearing-aid gain, while the literature indicates that occasionally the desired maximum intelligibility frequently is not obtained at the MCLL. We question whether MCLL for speech justifies its measurement. A discussion is presented of the Comfort Level Method of adjusting gain in hearing-aid evaluations and a perhaps preferable Threshold Level Method in which the test stimulus is presented at a level corresponding to the predicted threshold and the aid's volume control is adjusted until S just perceives the signal. 相似文献
95.
J P Johnson J C Carey W M Gooch J Petersen J F Beattie 《The Journal of pediatrics》1983,102(6):866-872
Three children with the femoral hypoplasia-unusual facies syndrome are described. Two had the characteristic facial pattern of upslanted palpebral fissures, long philtrum with thin upper lip, micrognathia, and hypoplastic alae nasi. The other, an infant girl who died within 24 hours after birth, had a cleft lip, which distorted some of the other features. She also had a cleft palate, as did one of the two older boys. All three children had ear defects, upper limb involvement, and rib, vertebral, lower extremity, and genitourinary tract abnormalities. The infant girl died of lung hypoplasia associated with dysplastic kidneys and widely patent ductus arteriosus. All three were infants of diabetic mothers, one mother having developed overt diabetes in the first trimester of pregnancy. A literature review of 36 reported cases of FH/UFS revealed 12 individuals who were IDMs, establishing a strong relationship of the syndrome with maternal diabetes. A multifactorial inheritance model fits with the reported patients, with the relationship to diabetes, and with the similarity of FH/UFS to caudal regression, another condition related to maternal diabetes. 相似文献
96.
BACKGROUND: As little has been published on the course of idiopathic solar urticaria (SU) patients cannot receive comprehensive prognostic advice. OBJECTIVE: To determine the prognosis and photobiological characteristics of idiopathic SU. DESIGN: Historical cohort study, with inception cohort followed up from time of diagnosis. Follow-up for a median of 4 years (range, 3 months to 26 years) after diagnosis. SETTING: Tertiary referral center for the investigation of photodermatoses in Scotland. PATIENTS: The study included 87 patients, 61 (70%) of whom were female, with phototest-confirmed idiopathic SU between 1975 and 2000. Sixty patients (69%) were followed up clinically, and 25 patients (29%) were phototested on 2 or more occasions. INTERVENTIONS: Investigations at time of diagnosis included monochromator phototesting. Further monochromator phototesting was performed in those patients in whom it was clinically indicated (select subgroup), and all patients who could be traced received a follow-up questionnaire. MAIN OUTCOME MEASURES: Characteristics of SU, responsible wave bands, and prognosis for clinical resolution. RESULTS: The prevalence of idiopathic SU in Tayside, Scotland, is estimated to be 3.1 per 100 000. Action spectra were typically broad, with 63% reacting to more than 1 wave band, and the most common provoking wavelengths were the longer UV-A and the shorter visible ones. The majority of subjects were affected perennially (68%), by radiation transmitted through glass (83%) and thin clothing (76%). Coexistent polymorphic light eruption occurred in 20 patients (23%), and another photodermatosis occurred in 6 patients, 3 of whom had chronic actinic dermatitis. In those with SU alone, the mean age at onset was 41 years. The probability of clinical resolution at 5 and 10 years after diagnosis was 0.12 (95% confidence interval, 0.06-0.24) and 0.26 (95% confidence interval, 0.15-0.43), respectively. CONCLUSION: Idiopathic SU is a chronic disease. The majority of this cohort was still affected after 5 and 10 years. 相似文献
97.
98.
Key A George CL Beattie D Stammers K Lacey H Waller G 《The International journal of eating disorders》2002,31(2):185-190
OBJECTIVE: This pilot study examined the role of mirror confrontation in the desensitization process of a body image treatment within an inpatient program for anorexia nervosa. METHOD: A within-subjects design was used. It compared the impact of two modes of group body image treatment on body dissatisfaction, anxiety, and avoidance behaviors. Both treatments followed a set format of exposure exercises and homework, but the modified treatment also included mirror confrontation as an exposure exercise. RESULTS: Standard treatment did not produce any significant changes. Modified treatment produced a significant and sustained improvement in body dissatisfaction and a significant reduction in body anxiety and avoidance behaviors. DISCUSSION: Mirror confrontation is a more effective form of exposure because of the strong emotional response it elicits. Patients' pronounced emotional response to this exercise allowed easier identification of the affective and behavioral components of body dissatisfaction and more cogent links into a developmental body image timeline. 相似文献
99.
Islet transplantation as a procedure to induce insulin independence is still a long way from benefitting the population of
more than 1 million type 1 diabetic patients in the United States. In addition to the problems involved with immune suppression,
the most significant obstacle is a scarcity of human organs for transplantation. In 1999, only 5882 donated pancreases were
available, of which only 50% could be expected to produce islet yields suitable for clinical purposes. In this article, we
review various sources with the potential to provide tissue for transplantation. These sources include islet and nonislet
cells derived from both human and nonhuman sources, with an emphasis on human cells. 相似文献
100.
Cosmetic camouflage advice improves quality of life 总被引:5,自引:0,他引:5
BACKGROUND: The subjective benefit of attendance at cosmetic clinics has not previously been reported. OBJECTIVES: To assess the effect on perceived quality of life (QoL) of cosmetic camouflage advice. METHODS: In a three-centre study, 135 individuals were invited to complete a dermatology-specific QoL measure, the Dermatology Life Quality Index (DLQI), before and 1 month after their first visit to a cosmetic camouflage clinic. RESULTS: Eighty-two completed DLQI questionnaires were returned before the camouflage clinic appointment, and 56 corresponding questionnaires were returned 1 month after. The mean age of responders was 50 years, and the mean duration of their skin conditions was 15 years. The main conditions seen were pigmentary disorders (29%), scars (22%) and vascular disorders (13%). There was a significant difference in mean DLQI scores before and after the clinic visit (9.1 vs. 5.8, P = 0.0001). CONCLUSIONS: When assessed at 1 month, attendance at a cosmetic camouflage clinic appears to improve QoL significantly. 相似文献