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  • 简介:Inthepresentpaper,afour-stageperforationmodelthataccuratelypredictstheresidualvelocityisdevelopedbyadoptinganenergymethod.Thefourstagesareplugformation,dishingformation,petalformationandprojectileexit.Inaddition,someimportantexperimentalresultsarepresentedandanalyzedtovalidatethepresentperforationmodel.Intheexperiments,highspeedcamerasystemisusedtorecordtheperforationprocess.Observationsontargetdamageandmeasurementsofinitialvelocitiesandresidualvelocitieswiththeaidofthesystemarepresented.Numericalsimulationsarecarriedoutforprojectilesagainstsingleandlayeredplatesadoptedintheexperiments.Theperforationprocessisstudiedandthedeformationandfailuremodesareobtained.Thepredictionsofnumericalsimulationsandanalyticalmodelarefoundinreasonablygoodagreementwiththoseofexperiments,andcanbeusedtopredicttheballisticlimitandresidualvelocityofstiffenedplatesperforatedbyrigidprojectiles.

  • 标签: 刚性发射 穿孔 碰撞 硬质板 数字模拟 故障模式
  • 简介:Aratmodelofchronictympanicmembraneperforationwasdevelopedtobeusedinthesearchofnewmaterialsforthesealingoftheseperforations.AlongitudinalstudywascarriedoutinratssubjectedtoincisionalmyringotomyfollowedbytheapplicationofmitomycinCaloneorwithdexamethasone.Ratswerecheckedatdays3,7,10,14andweeklythereafteruntilperforationclosure,forupto6months.Theadditionofdexamethasoneisakeycomponentinordertoobtainachronicopening.Myringotomiestreatedwithsalinehadameanhealingtimeof8.5days.At8weeks,between62.5%and77.7%oftympanicmembranestreatedwithmitomycinCanddexamethasoneremainedperforatedandat6monthsthisnumberfellto21.4%.Thistechniqueisabletomaintainmosttympanicmembraneperforationspatentforatleast8weeks.Thisratmodelisadequateforitsuseinpreclinicalortranslationalresearch.

  • 标签: ANIMAL model CHRONIC tympanic MEMBRANE PERFORATION
  • 简介:Objectives:Recentstudieshaveintroducedmiddleearvolume(MEV)asanoveldeterminantofperforation-inducedconductivehearingloss(CHL)inamechanismdrivenbytrans-tympanicmembranepressuredifferences.Theprimaryaimsofthispreliminaryreportareto:1)correlateCHLwithperforationsize;2)describetherelationshipbetweenCHLandMEV;and3)compareCHLacrossarangeofcholesteatomainvolvement.Design:Aretrospectivepilotstudywasperformedin31subjectswithaudiometryindicativeofconductivehearingloss,temporalboneCTscans,andnopriormiddleearsurgery.PerforationsizeandMEVwereanalyzedwithrespecttoCHLinacohortof10perforatedearswithnocholesteatoma.CHLswerecomparedin3groupsdefinedbyextentofcholesteatomainvolvement.Results:EarswithlargeandsmallperforationsshowedmeanABGvaluesof32.0±15.7dBand16.0±16.4dB,respectively.AdirectrelationshipwasobservedbetweenMEVandCHLforearswithlargeperforationsacrossallfrequencies,whereasthisrelationshipforsmallperforationswasfrequency-dependent.Finally,astatisticallysignificantincreaseinCHLwasfoundacrossearswithincreasingcholesteatomainvolvementat1000Hz(c2(2)9.786,p0.008),2000Hz(c2(2)8.455,p0.015),and4000Hz(c2(2)8.253,p0.016).Conclusions:Thesepilotdatasuggestthatgreaterperforation-inducedconductivehearinglossesmaybeassociatedwithlargerperforationsizesandcholesteatoma.ThecorrelationbetweenMEVandCHLmayrequireadditionalstudy.

  • 标签: Perforation-induced HEARING LOSS CONDUCTIVE HEARING LOSS
  • 简介:INTRODUCTIONWiththedevelopmentofeconomyandimprovementoflifequality,theincidencesofhypertension,hyper-cholesterolemia,diabetes,obesityandsmokinghavebeenincreasedinChina,whichhasledtoasignificantincreaseinthemorbidityandmortalityofcoronaryarterydisease(CAD)~1.SinceitwasintroducedintoChinain1984,coronaryintervention(PCI)hasdevelopedrapidlyandhasbecomethemajortreatmentofCADbecauseofitsuniquecharacteristicsofminimalinvasiveand

  • 标签: 冠状动脉疾病 介入治疗 护理 穿孔 栓塞 生活质量
  • 简介:DearEditor,Inarecentinterventionalcasereport,Allonetal~([1])hydratedcornealstromawithcefuroximetosealasmalltraumaticleakycornealperforationthatwasunresponsivetopriorsoftbandagecontactlensapplicationfor6d.Wewouldliketojustremindthepossiblecomplicationsofintracameralcefuroximeineyeswithalreadycompromised

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  • 简介:Objective:InfraredTympanicThermometer(ITT)isoneofthemostusefulinstrumentsforaccuratelymeasuringtemperature.TheeffectsofearpathologiesonITTmeasurementremainunclear.Thepurposeofthisstudyistodetermineiftympanicmembraneperforation(TMP)affectsITTmeasurementsinadultpatients.Materialandmethods:Atotalof90adultpatientswithmonauralcentralTMPwereenrolledinthisstudy.Patientswerecategorizedintothreesubgroupsaccordingtoperforationsize(1-3mm,4-7mm,and8-10mm).Thetympanictemperaturesoftheaffectedandunaffectedsites,andsubgroupswerecomparedwitheachother.Results:Thisstudycontained54(60%)malesand36(40%)femalesrangingfrom20to58yearsofage(meanage:30.74±9.61years).ThemeantympanictemperatureofthesideaffectedwithTMPwas36.34oC±0.61oC.Themeantympanictemperatureoftheunaffectedsidewithhealthyandintacttympanicmembranewas36.33oC±0.6oC.ThePearsoncorrelationscoreforthetympanictemperaturesandthesizeofTMPwas0.22whichwasnotsignificant(r=-0.12).Conclusion:TMPandperforationsizedonotaffectITTmeasurementsinadultpatients.

  • 标签: Tympanic MEMBRANE PERFORATION INFRARED tympanic THERMOMETER
  • 简介:Introduction:Middleearvolume(MEV)isaclinicallyrelevantparameteracrossmiddleeardiseases.MEVvaluesbetweenthesetechniqueshaveneverbeforebeentestedforagreementinearswithperforatedtympanicmembranes(TMs).Methods:Middleearswereidentifiedfrom36patientsranging18e89yearsofagewithTMperforationswhounderwenttympanometryandtemporalbonecomputedtomography(CT)between2005and2015.MEVscalculatedbybothtympanometryandthree-dimensionalvolumereconstruction(3DVR)wereanalyzedforagreementusingBlandAltmanplots.Thedifferencesbetweentympanometricand3DVRMEVvaluesforeachgivenmiddleearwerecharacterizedacrossMEVquartiles(1?smallest;4?largest)andacrossincreasingstatesofmiddleeardiseaseusingKruskaleWallisandWilcoxontestingwithBonferronicorrection.Results:BlandAltmanplotsdemonstratedsignificantdisagreementbetweenMEVmeasurementtechniques.Differencesbetweentympanometric(T)and3DVRMEVvaluesweresignificantlygreaterwithincreasingaverage(i.e.(Tt3DVR)/2))MEVperlinearregression(p<0.0001).SignificancewasdemonstratedbetweenfourthandfirstaverageMEVquartiles(p?0.0024),fourthandsecondquartiles(p?0.0024),thirdandfirstquartiles(p?0.0048),andthirdandsecondquartiles(p?0.048).AbsoluteMEVdifferencewasnotsignificantlydifferentacrossvaryingstatesofmiddleeardisease(p?0.44).Conclusion:Statisticallyandclinicallysignificantdisagreementwasdemonstratedbetweentympanometricand3DVRMEVvalues.StudiesthatvaryinMEVestimationtechniquesmaybeexpectedtodemonstratesignificantlydifferentresults.ThesepreliminaryresultssuggestthatcliniciansshouldendeavortoseekfurtherconfirmationwheninterpretinghightympanometricMEVvalues.

  • 标签: MIDDLE EAR VOLUME Tympanometry THREE-DIMENSIONAL VOLUME
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  • 简介:AbstractIntertrochanteric fractures have become a severe public health problem in elderly patients. Proximal femoral nail anti-rotation (PFNA) is a commonly used intramedullary fixation device for unstable intertrochanteric fractures. Pelvic perforation by cephalic screw is a rare complication. We reported an 84-year-old female who fell at home and sustained an intertrochanteric fracture. The patient underwent surgery with PFNA as the intramedullary fixation device. Routine postoperative examination revealed medial migration of the helical blade that eventually caused pelvic perforation. We performed a cemented total hip arthroplasty as the savage procedure. At the latest follow-up of 12 months after total hip arthroplasty, the patient had no pain or loosening of the prosthesis in the left hip. Pelvic perforation should be considered when choosing PFNA as the intramedullary fixation device, especially in patients with severe osteoporosis wherein the helical blade can be easily inserted during the operation. The lack of devices to avoid oversliding of the helical blade in PFNA is an unreported cause of this complication and should be considered in such cases.

  • 标签: Hip fractures Intertrochanteric fractures Proximal femoral nail anti-rotation Complication Pelvic perforation Case report