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应用40Hz听觉相关电位与听性脑干反应评估听阈 总被引:5,自引:2,他引:3
对 42例 74耳(正常听力组 32耳,检案中主诉听力下降 42耳)分别进行纯音测定,声导抗测定,听性脑干反应 (Auditory Brainstem Response,ABR)及 0.5~ 2kHz范围的 40Hz听觉相关电位 (40Hertz Auditory Event- related Potential,40Hz AERP)测定,对其中 20耳进行睡眠及清醒两种状态的 40Hz AERP测定。将纯音听阈、 40Hz AERP反应阈、 ABR反应阈三者之间进行比较分析。结果表明,正常听力耳 40Hz AERP反应阈值较纯音测听阈值高,在不同频率的校正值 (差值 )不同, 0.5 kHz为 12.7± 6.4(dBnHL); 1kHz为 14.7± 6.3(dBnHL); 2 kHz为 15± 5.6(dBnHL)。 ABR阈值比行为听阈高,校正值为 8.9± 5.3(dBnHL)。睡眠状态时 40Hz AERP阈值较清醒状态阈值高,校正值为 9.7± 2.45(dBnHL)。检案中主诉听力下降者主、客观语音频率均值之间明显不相符 ,误差率为 61%。本研究表明单纯使用 ABR、纯音测听中任何一种方法估计语音频率听阈均有一定的误差。 相似文献
994.
大鼠脑挫伤后组织学及Bax/Bcl-2表达的研究 总被引:8,自引:2,他引:6
采用自制大鼠右顶叶局灶性脑挫伤模型,进行组织学和 Bax/Bcl- 2的免疫组织化学法研究。结果发现 :伤后 12h~ 24h,挫伤灶周围神经细胞和星形胶质细胞形态学发生改变,白细胞附壁和游出;伤后 4d,挫伤灶周围出现大量的泡沫细胞和核大而深染的星形胶质细胞; 8~ 10d,挫伤灶处形成软化灶; 12~ 14d,挫伤灶愈合变成胶质细胞结节,或者变成囊状,可见大量的星型胶质细胞及新生毛细血管,可见含铁血黄素颗粒沉积。 Bax/Bcl- 2表达水平与伤后经历时间有一定相关性。 相似文献
995.
Trueman DL 《Journal of health law》2000,33(2):191-262
Managed care entities face numerous liability issues in today's changing healthcare environment. This Article provides the plaintiff with a comprehensive road map for navigating the many avenues of managed care liability. The author describes ERISA pre-emption provisions and suggests ways plaintiffs' attorneys can strive to narrow the pre-emption. The Article also provides in-depth analysis of each theory of managed care liability that has been litigated against managed care entities to date, and then goes on to explore state laws imposing liability on managed care entities, and how HMO liability is being reformed through legislative action. For plaintiffs' attorneys seeking the full spectrum of theories of managed care liability, or for defendants' attorneys wanting to remain updated on all potential claims to defend, this Article constitutes an extensive primer on the current issues. 相似文献
996.
Ernst L. Moerk 《Journal of youth and adolescence》1973,2(4):303-312
The present study demonstrates that profiles of children from families with imprisoned fathers were more similar to those of juvenile delinquents and less similar to the norm group than were the profiles of children from divorced families. Based on findings presented, it would not be justified to conclude that father absence and father imprisonmentper se were the causes of negative psychological reactions. Discordant family relationships before the father left the family could have primarily caused the disturbance of these children.Received Ph.D. in psychology from the University of Innsbruck, Austria. Main research interest is developmental psychology. 相似文献
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Liu L 《Social security bulletin》2000,63(4):99-106
The March 2000 pension reform in Japan focused on the long-term financial sustainability of the country's two-tiered public pension system. The government opted for incremental changes in order to maintain pension solvency through 2060. Those changes could reduce future pension funding liability by an estimated one-third. Further, the decision to avoid structural reforms of its pension programs was based on fiscal considerations. Expanding general revenue funding for the first tier from the current share of one-third to cover the entire cost would require increases in the consumption tax that proved to be politically unacceptable. Fully privatizing the second, earnings-related tier would entail transition costs too great to bear at a time of rising budget deficits. In addition, the Japanese public generally supported the sharing of financial burden for public pension programs through a combination of benefit cuts, a raise in the pensionable age, and contribution rate increases. If current cost projections prove to be inaccurate, future pension reviews (scheduled every 5 years) will give the government further opportunity to fine-tune program changes. 相似文献
1000.