中耳功能异常对畸变产物耳声发射测试的影响

目的 探讨中耳传音功能异常对畸变产物耳声发射（DPOAE）测试结果的影响程度并在临床应用中加以识别和剔除。方法 将年龄2月－11岁56例（107耳）小儿依听力损失类型分为感音性聋组 和传导性聋组，并设置正常听力对照组，应用GSI 60耳声发射仪分别观察其DPOAE的DP检出率、DP幅值、DP与NF幅值差及相同参数条件下DPOAE测试时间。结果 耳蜗功能严重受损和渗出性中耳炎所记录到的DPOAE各测量参数之间的差异无统计学意义（P＞0．05）。结论 中耳积液导致的中耳传音功能障碍对DPOAE测试结果的影响，与耳蜗功能严重损害时所记录到的DPOAE参数变化，在临床检测中难以区分。因此，临床上在应用DPOAE进行听力评估之前，首先要检测受检者的中耳功能，剔除其对DPOAE检测结果的影响，确保结果的可靠性。     

麻醉和清醒大鼠DPOAE特性比较

目的探讨正常大鼠畸变产物耳声发射（DPOAE）的基本特征，比较麻醉和清醒状态下大鼠DPOAE各参数的变化。方法采用CELESTA-503型耳声发射分析仪对10只（20耳）健康大鼠行清醒和麻醉两状态下DPOAE“听力图”和输入／输出曲线及阈值进行测试。结果各频率的DPOAE检出率均为100％，2kHz以上DPOAE幅值均大于25dBSPL，反应幅值大，反应稳定，在正常剂量麻醉状态下其DPOAE幅值和I／O曲线斜率与清醒状态下相比无统计学意义（P〉0．05）。结论在麻醉状态下检测大鼠同清醒状态相比，操作简便、结果稳定，亦接近于生理状态。     

畸变产物耳声发射、新生儿行为神经测定评价新生儿窒息分析

目的为了探讨新生儿窒息所致中枢神经元缺氧性损伤及耳蜗毛细胞功能的损害对新生儿早期听力的影响;和评价DPOAE、NBNA在其中价值。方法对36例新生儿窒息进行畸变产物耳声发射及NBNA评价。结果正常新生儿的耳声发射与NBNA评分中行为能力3项通过时间比较无显著性差异P〉0.05;在正常与窒息新生儿及轻度与重度窒息中,比较NBNA中行为能力3项与耳声发射通过时间均有显著性差异P〈0.001。结论提示正常新生儿耳声发射与NBNA评分中的行为能力3项通过基本同步;新生儿窒息所导致耳蜗毛细胞功能及中枢神经元的损害恢复不同步;窒息越严重,耳蜗毛细胞功能及听觉中枢神经元功能恢复越慢。     

早产儿听力筛查的特点及影响因素分析

目的通过耳声发射（OAE）研究早产儿听力的基本特点,寻找适合早产儿听力筛查的方法、时间并探讨早产儿听力的影响因素。方法应用耳声发射仪,对160例早产儿进行耳声发射测试（DPOAE）,测试结果不能通过者,42天后复查,仍不能通过者于生后3个月再次复查并行脑于诱发电位（ABR）检查,并对所有早产儿按胎龄、体重、分娩方式、窒息、黄疸及感染进行分组,探讨早产儿听力的影响因素。结果 DPOAE快速、方便、无损伤,可作为早产儿听力筛查的有效方法;测试结果与体重、窒息、黄疸、感染密切相关。     

顺铂对豚鼠耳蜗形态与Bcl-2表达的影响

目的 探讨顺铂对豚鼠耳蜗毛细胞耳毒性作用的形态学改变以及顺铂对螺旋神经节细胞Bcl-2蛋白表达的影响.方法 在实验动物被处死前,检测其畸变产物耳声发射（DPOAE）幅值变化.取左侧耳蜗,行耳蜗铺片,观察基底膜毛细胞.右侧耳蜗冰冻切片,用免疫组织化学方法检测Bcl-2的表达.结果 对照组耳蜗铺片显示内、外毛细胞结构完整,排列整齐.顺铂组毛细胞肿胀,纤毛缺失,DPOAE幅值和螺旋种经节的Bcl-2表达明显低于正常对照组（P＜0.01）.结论 顺铂引起耳蜗内、外毛细胞发生形态学改变,其耳毒性作用可能与抑制Bcl-2蛋白的表达有关.     

HS-OAE耳声发射检测系统的研制与开发

耳声发射(OAE)是产生于内耳耳蜗,经听骨链和鼓膜传导,释放到外耳道的音频能量,在临床中有广泛应用.本文详细介绍了HS-OAE耳声发射检测系统的研制.该系统基于个人计算机和多媒体声卡实现,能够检测TEOAE和DPOAE两种耳声发射信号.硬件方面,检测系统由声学传感器,前置处理器,多媒体声卡和计算机四部分组成;软件方面,除了能够检测两种耳声发射信号,系统还实现了对病案数据的管理,制作检测报告等辅助功能.检测系统的输出声学参量经过校准,符合有关要求.文章最后介绍了与同类检测设备ILO耳声发射检测仪进行的临床对照试验的情况.临床试验的结果表明,HS-OAE耳声发射检测系统已经具备临床应用水平.     

早产儿听力筛查方法及影响因素分析

目的通过耳声发射（OAE）研究早产儿听力的基本特点,寻找适合早产儿听力筛查的方法、时间并探讨早产儿听力的影响因素。方法应用耳声发射仪,对408例早产儿进行畸变产物耳声发射测试（DPOAE）,测试结果不能通过者,42天后复查,仍不能通过者于生后3个月再次复查并行脑干诱发电位（ABR）检查,并对所有早产儿按胎龄、体重、分娩方式、窒息、黄疸及感染进行分组,探讨早产儿听力的影响因素。结果DPOAE快速、方便、无损伤,可作为早产儿听力筛查的有效方法;在胎龄34周后进行初筛可以减少假阳性率;测试结果与体重、窒息、黄疸、感染密切相关。     

诱发电位的基础知识及其进展(续)

3　诱发电位在临床应用方面的　新技术3 1　听觉诱发电位方面3 1 1　耳声发射及临床应用耳声发射 (ｏｔｏａｃｏｕｓｔｉｃｅｍｉｓｓｉｏｎ ,ＯＡＥ)是指产生于耳蜗 ,而在外耳道内记录到的声信号。早在 1948年Ｇｏｌｄ就从理论上提出耳蜗不仅能感受声音 ,还可能产生声音 ,即耳蜗具有双向放大作用。但由于当时受检测技术条件的限制 ,未能得到实验证明 ,直到 1978年Ｋｅｍｐ首次从外耳道记录到瞬态耳声发射 (ＴＥＯＡＥ) ,次年又记录到畸变产物耳声发射 (ＤＰＯＡＥ) ,人们对此问题才又重新认识。从总体来说 ,耳声发射分为两大类 :①自发性耳…     

噪声性聋患者听觉传出神经系统功能的改变

目的： 研究噪声性聋患者听觉传出神经系统功能的改变，为临床对噪声性聋进行早期监测和诊断提供可靠的方法和依据。方法: 以Celesta-503型耳声发射分析仪测试并记录受试者畸变产物耳声发射（DP-gram和2、4、6 kHz的I/O曲线），以对侧宽带噪声（70 dB SPL）刺激后畸变产物耳声发射幅值的改变评价听觉传出神经系统功能的改变。结果: 在DP-gram的测试中，噪声性聋患者的对侧抑制效应在低频（0.75 kHz和1 kHz）明显低于对照组和听阈正常组，而在中高频无显著差异；在I/O曲线测试中，噪声性聋患者对侧抑制效应仅在2 kHz中低强度段低于对照组和听阈正常组受试者，而在4 kHz及6 kHz的测试中，无显著差异。结论: 噪声性聋患者的听觉传出神经功能减弱，对听觉传出神经系统功能的测试可为早期监测和诊断噪声性聋提供依据。     

清醒和麻醉状态下豚鼠畸变产物耳声发射检测比较

为了观察豚鼠在麻醉和清醒状态的畸变产物耳声发射 (DPOAE)。我们以 DPOAE幅值和 I/ O曲线作为参数 ,观察清醒和麻醉状态下其参数的变化。结果发现豚鼠在清醒状态下其 DPOAE幅值和 I/ O曲线斜率与正常剂量麻醉状态下相比无显著性差异 (P>0 .0 5 )。我们认为在清醒状态下豚鼠 DPOAE的检测同麻醉状态相比 ,操作简便、结果稳定 ,更接近于生理状态。     

Level of functioning of siblings and parents of probands of varying degrees of retardation

A further analysis of already published data supports the position that retardates of low ability level less frequently have retarded siblings, retarded parents, and parents low in occupational level than do retardates higher in ability level. The analysis supports the position that there are two types of retarded individuals, persons retarded as a result of gene or chromosomal anomalies, brain injury, etc., who more frequently occur in the lower-level retardate group, and persons whose retardation represents polygenic segregation, who more frequently occur in the higher-level group.     

Recovery of responsiveness of cells of lateral geniculate nucleus of rat

1. Recovery of responsiveness of single cells in lateral geniculate nucleus of rat has been determined in both P and I cells. There are three types of recovery curve among P cells; (a) early recovery, (b) early partial recovery followed by depression and then complete recovery, (c) prolonged depression followed by cyclic recovery. Type (c) is by far the commonest recovery curve. In contrast to the spike in a P cell, the synaptic potential recovers to its full amplitude in about 20 msec. All I cells exhibit similar rapid recovery curves after a prolonged depression.2. Conditioning stimuli applied to visual cortex also produce a prolonged depression in most P cells but I cells can be re-excited at short intervals from cortex. Decortication does not prevent the prolonged depression of the multineuronal response produced by optic nerve stimulation.3. A neuronal model is proposed to explain these observations. It is supposed that I cells (interneurones) are innervated by axon collaterals of the P cells (principal cells, projecting to visual cortex) and that the I cells exert an inhibitory influence on the P cells.     

Modes of Inheritance of Errors of Refraction

Eighteen families in which both parents had refractions within the range of +4·0 D to −4·0 D and axial lengths seen in emmetropia (22·3-26·0 mm) showed coefficients of correlation of the order 0·5 indicative of polygenic inheritance. Such coefficients were seen for axial length (0·407) and for the cornea (0·487), but not for the lens (which is known to be yoked to the axial length). No such coefficients were seen in 19 families in which one of the parents had axial length outside the emmetropic range (nine families with long axes and 10 with short axes).

The pattern of polygenic inheritance for emmetropia (completely correlated optical components) and errors of refraction up to 4·0 D (inadequately correlated components: correlation ametropia) follows that seen in stature and other measurable characters. In contrast the high refractive errors with their abnormal axial lengths (component ametropia) are—like the extremes in stature—pathological anomalies with monofactorial inheritance.

     

Evaluation of antibacterial activity of extracts of five species of wood-colonizing fungi

Screening new organisms for antibacterial activity and searching for new antibacterial drugs is important due to the constant generation of new antibiotic-resistant strains of pathogenic bacteria. An E. coli broth microdilution test was used to evaluate the results of the Vibrio fischeri bioluminescence test in five of the most antibacterially active species of wood-colonizing fungi. Serpula lacrymans was found to be a potential source of thermostable antibiotic(s) and the Vibrio fischeri bioluminescence test was confirmed to be a useful method for screening for antibacterial activity.