学科分类
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24 个结果
  • 简介:Thekeratoprosthesis(KPro;artificialcornea)isaspecialrefractivedevicetoreplacehumancorneabyusingheterogeneousformingmaterialsfortheimplantationintothedamagedeyesinordertoobtainacertainvision.Themainproblemsofartificialcorneaarethebiocompatibilityandstabilityofthetissueparticularlyinpenetratingkeratoplasty.Thecurrentstudiesoftissue-engineeredscaffoldmaterialsthroughcomprisingcompositesofnaturalandsyntheticbiopolymerstogetherhavedevelopedanewwaytoartificialcornea.Althoughawideagreementthatthelong-termstabilityofthesedeviceswouldbegreatlyimprovedbythepresenceofcorneacells,modificationofkeratoprosthesistosupportcorneacellsremainselusive.Mostofthestudiesoncornealsubstratematerialsandsurfacemodificationofcompositeshavetriedtoimprovethegrowthandbiocompatibilityofcorneacellswhichcannotonlyreducethestimulusofheterogeneousmaterials,butalsomoreimportantlycontinuousandstablecorneacellscanpreventthedestructionofcollagenase.Thenecrosisofstromaandspontaneousextrusionofthedevice,allowformaintenanceofaprecornealtearlayer,andplaytheroleofensuringagoodopticalsurfaceandresistingbacterialinfection.Asaresult,improvementincornealcellshasbeenthemainaimofseveralrecentinvestigations;someefforthasfocusedonbiomaterialforitswellbiologicalpropertiessuchaspromotingthegrowthofcorneacells.Thepurposeofthisreviewistosummarythegrowthstatusofthecornealcellsaftertheimplantationofseveralartificialcorneas.

  • 标签: artificial CORNEA KERATOPROSTHESIS tissue-engineered SCAFFOLD CORNEAL
  • 简介:AIM:Todescribethedesignandpreliminaryresultsofthehospitalbasedepidemiologicalstudyfordiabeticretinopathy(HBESDR),anongoingepidemiologicalstudytoestimatetheprevalenceofdiabeticretinopathy(DR)andtoelucidatetheclinical,anthropometric,biochemicalandanyotherriskfactorsassociatedwithdiabeticretinopathy.METHODS:Totally2000diabeteswillberecruitedfromtheDiabeteseyeclinicintheFirstAffiliatedHospitalofChinaMedicalUniversity.AllsubjectsunderwentbloodsugarestimationandOralGlucoseToleranceTesttodiagnosediabetes.Alldiabeteswouldundergocompletequestionnaire,acomprehensiveeyeexamination.Bloodandurinewouldbecollectedforbiochemicalinvestigations.AllfundusphotographsforanyDRwillbegraded.Participantswhoneedtreatmentwillbesenttotheophthalmicclinicandfollow-upintervalprogramforallsubjectswillbesuggested.Acomputerizeddatabaseiscreatedfortherecords.RESULTS:Todate,1174diabeteshavebeenrecruited,therewere350(29.81%)DRinalldiabetes,mostofthemwerewithmildnon-proliferativediabeticretinopathy(NPDR)(139,39.71%);71(20.29%)moderateNPDR,66(18.86%)severeNPDR,74(21.14%)proliferativediabeticretinopathy(PDR).Females,longerdurationofdiabetes,familyhistoryofdiabetesandhypertensionhadastatisticallysignificantincreaseinriskofanyDR.CONCLUSION:ThestudyisexpectedtoprovideanestimateoftheoverallprevalenceofDRandtheprevalencewithdifferentdurationofdiabetesandalsoabetterunderstandingoftheriskfactorsassociatedwithDR.

  • 标签: DIABETIC RETINOPATHY PREVALENCE epidemiolo-gical STUDY
  • 简介:AIM:Toevaluatetheaccuracyofsphericalequivalent(SE)estimatesofadouble-passsystemandtocompareitwithretinoscopy,subjectiverefractionandatablemountedautorefractor.METHODS:Non-cycloplegicrefractionwasperformedon125eyesof65healthyadults(age23.5±3.0years)fromOctober2010toJanuary2011usingretinoscopy,subjectiverefraction,autorefraction(AutokeratorefractometerTOPCONKR-8100,Japan)andadoublepasssystem(OpticalQualityAnalysisSystem,OQAS,VisiometricsS.L.,Spain).Nineconsecutivemeasurementswiththedouble-passsystemwereperformedonasubgroupof22eyestoassessrepeatability.ToevaluatethetruenessoftheOQASinstrument,theSElaboratorybiasbetweenthedoublepasssystemandtheothertechniqueswascalculated.RESULTS:TheSEmeancoefficientofrepeatabilityobtainedwas0.22D.SignificantcorrelationscouldbeestablishedbetweentheOQASandtheSEobtainedwithretinoscopy(r=0.956,P<0.001),subjectiverefraction(r=0.955,P<0.001)andautorefraction(r=0.957,P<0.001).ThedifferencesinSEbetweenthedouble-passsystemandtheothertechniquesweresignificant(P<0.001),butlackedclinicalrelevanceexceptforretinoscopy;Retinoscopygavemorehyperopicvaluesthanthedouble-passsystem-0.51±0.50Daswellasthesubjectiverefraction-0.23±0.50D;Moremyopicvalueswereachievedbymeansofautorefraction0.24±0.49D.CONCLUSION:Thedouble-passsystemprovidesaccurateandreliableestimatesoftheSEthatcanbeusedforclinicalstudies.Thistechniquecandeterminethecorrectfocuspositiontoassesstheocularopticalquality.However,ithasarelativelysmallmeasuringrangeincomparisonwithautorefractors(-8.00to+5.00D),andrequirespriorinformationontherefractivestateofthepatient.

  • 标签: DOUBLE-PASS system optical quality RETINOSCOPY autorefraction
  • 简介:AIM:Todemonstratethemorphologyandstructureofinvitroreconstructedtissue-engineeredhumancornealepithelium(TE-HCEP)withseedercellsfromanuntransfectedHCEPcellline.·METHODS:TheTE-HCEPswerereconstructedinvitrowithseedercellsfromanuntransfectedHCEPcellline,andscaffoldcarriersofdenudedamnioticmembrane(dAM)inair-liquidinterfaceculturefor3,5,7and9days,respectively.Thespecimenswereexaminedwithhematoxylin-eosin(HE)stainingofparaffin-section,immunocytochemicalstaining,scanningandtransmissionelectronmicroscopy.·RESULTS:DuringinvitroreconstructionofTE-HCEP,HCEPcellsformeda3-4,6-7and8-10layersofanHCEP-likestructureondAMsinair-liquidinterfaceculturefor3,5and7days,respectively.Butthecellsdeceasedto5-6layersandthestructureofstraifiedepitheliumbecamelooseatday9.Andthecellsmaintainedpositiveexpressionofmarkerproteins(keratin3andkeratin12),cell-junctionproteins(zonulaoccludens-1,E-cadherin,connexin43andintegrinβ1)andmembranetransportproteinofNa+-K+ATPase.TheHCEPcellsinTE-HCEPwererichinmicrovillionapicalsurfaceandestablishednumerouscell-cellandcell-dAMjunctionsatday5.·CONCLUSION:ThemorphologyandstructureofthereconstructedTE-HCEPweresimilartothoseofHCEPinvivo.TheHCEPcellsinthereconstructedTE-HCEPmaintainedthepropertiesofHCEPcells,includingabilitiesofformingintercellularandcell-extracellularmatrixjunctionsandabilitiesofperformingmembranetransportation.TheuntransfectedHCEPcellsanddAMscouldpromisinglybeusedinreconstructionHCEPequivalentforclinicalcornealepitheliumtransplantation.

  • 标签: tissue-engineered HUMAN CORNEAL epithelium in VITRO