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991.
Conclusions: In patients with total sudden sensorineural hearing loss (SSNHL), oral prednisone (OP) alone or intratympanic dexamethasone (ITD) alone have comparable results. The addition of salvage ITD following OP does not seem to add over either single modality treatment. Objectives: To study the effect of steroid-based treatments in patients with total SSNHL. Methods: The medical charts of 59 patients with total loss of hearing, defined as pure tone thresholds in the profound range (> 90 dB) with an unobtainable speech reception threshold (SRT) that were treated with OP (n = 20), ITD (n = 13), or OP followed by salvage ITD (n = 26) were analyzed. Response to treatment was evaluated by means of pure tone thresholds, SRT, and speech discrimination score (SDS), immediately after treatment and on a follow-up visit. Results: Forty-nine patients (83%) responded to treatment, with mean significant improvements of 36, 34, 31, and 25 dB at 500, 1000, 2000, and 4000 Hz, respectively. The mean improvement in SRT was 33 dB, and SDS improved by 32%. There were no differences in improvement in pure tone thresholds and SRT among the three treatment groups. The late effect of OP was similar to the effect of salvage ITD.  相似文献   
992.
Objective: While the benefits of hearing aids among older adults with presbycusis have been well documented, there is limited research on hearing-aid usage. The aim of this review is to synthesize current evidence to identify the determinants of hearing-aid adoption and use among the elderly. Design: Systematic review. Study sample: Articles were identified through systematic searches in the Web of Science, Medline, CINAHL, and a manual search. Studies that explore the potential determinants of hearing-aid usage were to be included. Results: A total of twenty-two articles were reviewed. Four audiological determinants (the severity of hearing loss, the type of hearing aids, background noise acceptance, and insertion gain) and seven non-audiological determinants (self-perceived hearing problems, expectation, demographics, group consultation, support from significant others, self-perceived benefit, and satisfaction) were identified as affecting the adoption and use of hearing aids. Conclusions: There is a need to explore the influence of significant others, health professionals, and user demographics on hearing rehabilitation for future research. The determinants identified in this review depicted the stage progression of the trans-theoretical model (TTM) in explaining an individual's readiness to hearing-aid usage.  相似文献   
993.
Objective: Evaluation of the characteristic differences between click-and CE-Chirp-evoked auditory brainstem responses (ABRs) in normal hearing and sensorineural hearing loss. Design: A prospective study. Ears with normal hearing and with sensorineural hearing loss were evaluated. Pure-tone audiometry and click-and CE-Chirp evoked ABRs exams were conducted for all ears. Visual detection levels, wave-V amplitudes, and latencies of the ABRs were assessed. Study sample: Twenty-two ears with normal hearing and 22 ears with sloping type sensorineural hearing loss were examined. Results: In normal-hearing ears, mean amplitudes were larger for CE-chirps than for clicks at all intensities until 80 dB nHL, at which the amplitudes dropped off, presumably due to upward spread of excitation. In ears with sensorineural hearing loss, however the drop-off was less significant at 80 dB nHL. Comparisons with pure-tone audiometry findings revealed ABRs to CE-Chirps to correlate at 0.5, 1, 2, and 3 kHz, and to clicks at 1, 2, 3, and 4 kHz. Conclusions: The CE-Chirp has advantages over clicks for examining normal ears. However, under high-level stimulation, these advantages are no longer present. In ears with sensorineural hearing loss, the upward spread of excitation is less prominent. The CE-Chirps results correlate significantly to low frequency audiometric findings at 0.5 kHz, while clicks do not.  相似文献   
994.
995.
Objective To evaluate the effect of mitochondrial DNA(mtDNA) secondary mutations,haplotypes,GJB2 gene mutations on phenotype of 1494C > T mutation,and to study the molecular pathogenic mechanism of ma...  相似文献   
996.
Mutations in the CDH23 gene are known to be responsible for both Usher syndrome type ID (USH1D) and non-syndromic hearing loss (DFNB12), and the molecular confirmation of the CDH23 gene has become important in the diagnosis of these conditions. The present study was performed to find whether the CDH23 mutations are also responsible for non-syndromic hearing loss in patients in the Japanese population. A total of 51 sequence variants were found in 64 Japanese probands with non-syndromic sensorineural hearing impairment from autosomal recessive families. Among them, at least four missense mutations in six patients from five families were confirmed to be responsible for deafness by segregation study. All mutations detected were missense mutations, corroborating the previous reports regarding DFNB12. The present data confirmed that CDH23 mutations are frequently found and significantly responsible in Japanese. Interestingly, the CDH23 mutation spectrum in Japanese is very different from that found in Caucasians. This Japanese spectrum may be representative of those in Eastern Asian populations and its elucidation is expected to facilitate the molecular diagnosis of DFNB12 and USH1D.  相似文献   
997.
目的对两个中国Leber遗传性视神经病变(Leber’shereditary optic neuropathy,LHON)家系的临床和分子遗传学特征进行分析。方法眼科临床检查发现在这两个家系中只有先证者1人出现视力障碍,发病年龄分别为10岁和17岁。对这两个家系先证者使用24对有部分重叠的引物进行线粒体DNA(mitochondrial DNA,mtDNA)全序列扩增分析。结果没有发现mtDNAG11778A、G3460A和T14484C3个常见的突变位点,而发现了与LHON相关的ND4G11196A同质性突变位点的存在,在167名正常对照只发现1例G11696A突变。结论线粒体DNA全序列分析发现两个家系呈现独特的mtDNA多态性,都属于东亚单体型D4。不完全外显率和正常对照频率(1/167)表明G11696A突变本身不足以导致LHON的发生,说明其它因素在这两个LHON家系的表型表达中也起一定的作用。在这些家系mtDNA中缺乏影响重要功能突变位点的存在,排除了线粒体背景对LHON临床表型的影响。因此,核修饰基因、环境因素可能对两个中国G11696A突变家系的外显率和发病严重程度起促进作用。  相似文献   
998.
We evaluated the hypothesis that females would show a greater postexercise hypotension and concurrently a greater increase in the onset threshold for sweating. Fourteen subjects (7 males and 7 females) of similar age, body composition, and fitness status participated in the study. Esophageal temperature was monitored as an index of core temperature while sweat rate was measured by using a ventilated capsule placed on the upper back. Subjects cycled at either 60% (moderate) or 80% (intense) of peak oxygen consumption followed by 20-min recovery. Subjects then donned a liquid-conditioned suit used to regulate mean skin temperature. The skin was then heated (∼4.3°C·h−1) until sweating occurred. Esophageal temperatures were similar to baseline before the start of whole body warming for all conditions. The postexercise threshold values for sweating following moderate and intense exercise were an esophageal temperature increase of 0.10 ± 0.02 and 0.22 ± 0.04°C, respectively for males, and 0.15 ± 0.03 and 0.34 ± 0.01°C, respectively for females. All were elevated above baseline resting (P < 0.05) and a significant sex-related difference was observed for sweating threshold values following intense exercise (P < 0.05). This was paralleled by a greater decrease in mean arterial pressure in females at the end of the 20-min recovery (P < 0.05). In conclusion, females demonstrate a greater postexercise onset threshold for sweating, which is paralleled by a greater postexercise hypotensive response following intense exercise.  相似文献   
999.
BACKGROUND: Pregnancy loss before 6 weeks' gestation is common, but little has been reported about the associated bleeding. We compared women's bleeding following a pregnancy loss before 6 weeks' gestation with their typical menstruation. METHODS: Women provided daily urine samples while trying to become pregnant and recorded the number of pads and tampons used each day. Thirty-six women had complete bleed data for a loss before 6 weeks' gestation and one or more non-pregnant cycles. RESULTS: Mean bleed length following a pregnancy loss was 0.4 days longer than the woman's average menstrual bleed (P = 0.01), primarily because of more days of light bleeding. Although there was no overall increase in the total number of pads plus tampons used, women with losses bled less than their typical menses following pregnancies of very short duration and more than usual for the pregnancies lasting the longest. CONCLUSIONS: Overall, the bleeding associated with pregnancy loss before 6 weeks' gestation is similar to menstrual bleeding and unlikely to be recognized as pregnancy loss. The intriguing finding that pregnancies of very short duration were associated with less bleeding than the woman's typical menses might reflect endometrial factors associated with loss.  相似文献   
1000.
PROBLEM: A decrease in factor XII (FXII) activity has been observed in women with unexplained recurrent miscarriages. Because of the many similarities between recurrent in vitro fertilization-embryo transfer (IVF-ET) failure and early pregnancy loss patients, we investigated whether women with recurrent IVF-ET failure had low FXII activity. METHOD OF STUDY: Blood from 110 patients with three or more IVF-ET failures was tested for FXII activity, autoantibodies and other coagulation parameters. These patients were compared with 191 recurrent miscarriage patients, 87 controls. FXII activity was measured by an activated partial thromboplastin time (APTT) assay. RESULTS: Factor XII activity of the IVF-ET failure group (median 79.5, range 37-150) was significantly lower than that of control group (median 109, range 35-225, P < 0.001 by Mann-Whitney test) or that of recurrent pregnancy loss (RPL) group (median 92, range 20-205). The FXII activity of IVF-ET failure patients was positively correlated with age, but not associated with the number of IVF-ET failures, infertile duration, autoantibodies, or other coagulation parameters. CONCLUSION: Decreased FXII activity may causally relate to reproductive failure.  相似文献   
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