简介:Objective:Establishnormativedatafortympanicelectrocochleography(TMECochG)parametersinnormalhearingadultswithoutMeniere'sdisease's(MD)symptoms.DescribeTMECochGvariablesthathelptodistinguishnormalfromMDears.Materialandmethods:Weenrolled100subjects(N?200ears),59females,agedbetween19and71yearsfrom09/2010to04/2014.Inclusioncriteria:normalotomicroscopy,hearingthresholds25dBnHLfrom250to4000Hz,normaltympanogram,nosymptomsofMDaccordingtotheAAO-HNS1995criteriaandGibson'sscore<7.Weexcludedsubjectswithdizziness,auralfullnessorothersymptomsofendolymphatichydrops.Thefollowingparameterswereanalyzed:SP/APamplituderatio,SP/AParearatioandthedifferencebetweenAPlatencywithrarefactionandcondensationstimuli.Results:Therewasnosignificantdifferencebetweenrightandleftears(Intraclasscorrelationcoefficient<0.6).SP/APamplituderatiovariedbetween0.084and0.356andSP/AParearatiobetween0.837and1.671(percentiles5and95).TheAPlatencydifferencetorarefactionandcondensationclickswasbetween0.0and0.333ms.Conclusion:NormativedataforTMECochGparameterswereestablishedin100normalhearingsubjectswithoutMD.Thesedatacanbeusedtodistinguishnormalfrompathologicalfindingsandinfollow-upofMDpatients.
简介:摘要每个数学结论都有其成立的条件,每一种数学方法的使用也往往有其适用范围,在我们所遇到的数学问题中,有些问题的结论不是唯一确定的,有些问题的结论在解题中不能以统一的形式进行研究,还有些问题的已知量是用字母表示数的形式给出的,这样字母的取值不同也会影响问题的解决,由上述几类问题可知,就其解题方法及转化手段而言都是一致的,即把所有研究的问题根据题目的特点和要求,分成若干类,转化成若干个小问题来解决,这种按不同情况分类,然后再逐一研究解决的数学思想,称之为分类讨论思想。