学科分类
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44 个结果
  • 简介:AIM:Todescribethecharacteristicsofmodulationtransferfunction(MTF)ofanteriorcornealsurface,andobtainthethenormalreferencerangeofMTFatdifferentspatialfrequenciesandopticalzonesoftheanteriorcornealsurfaceinmyopes.·METHODS:Fourhundredeyesfrom200patientswereexaminedunderSIRIUScornealtopographysystem.PhoenisanalysissoftwarewasappliedtosimulatetheMTFcurvesofanteriorcornealsurfaceatverticalandhorizontalmeridiansatthe3,4,5,6,7mmopticalzonesofcornea.TheMTFvaluesatspatialfrequenciesof5,10,15,20,25,30,35,40,45,50,55and60cycles/degree(c/d)wereselected.·RESULTS:TheMTFcurveofanteriorcornealsurfacedecreasedrapidlyfromlowtointermediatefrequency(0-15cpd)atvariousopticalzonesofcornea,thevaluedecreasedto0slowlyathigherfrequency(>15cpd).Withtheincreaseoftheopticalzonesofcornea,MTFcurvedecreasedgradually.3)Intherangeof3mm-6mmopticalzonesofthecornea,theMTFvaluesmeasuredathorizontalmeridianweregreaterthanthecorrespondingvaluesathorizontalmeridianofeachspatialfrequency,thedifferencewasstatisticallysignificant(P<0.05).At7mmopticalzonesofcornea,theMTFvaluesmeasuredathorizontalmeridianwerelessthanthecorrespondingvaluesatverticalmeridianat10-60spatialfrequencies(cpd),andthedifferencewasstatisticallysignificantin25,30,35,40,45,50cpd(P<0.05).·CONCLUSION:MTFcanbeusedtodescribetheimagingqualityofopticalsystemsatanteriorcornealsurfaceobjectivelyindetail.

  • 标签: MODULATION TRANSFER FUNCTION OPTICAL quality CORNEA
  • 简介:AIM:ToinvestigatetheexpressionsoftypeIcollagen,α2integrinandβ1integrinintheposteriorscleraofguineapigswithdefocusmyopiaandwhetherbasicfibroblastgrowthfactor(bFGF)injectioninhibitstheformationanddevelopmentofmyopiabyupregulatingtheexpressionoftypeIcollagen,α2integrinandβ1integrin.METHODS:After14daysoftreatment,therefractivestateandaxiallengthweremeasuredandthelevelsoftypeIcollagen,α2integrinandβ1integrinwereassayedintheposteriorscleraeofgroupsofguineapigsthatworeamonocular-7Dpolymethylmethacrylate(PMMA)lensorhad-7DlenswearfollowedbytheperibulbarinjectionofPhosphateBufferSolution(PBS)orbFGF.Theuntreatedfelloweyeservedasacontrol.Guineapigswithnotreatmentservedasnormalgroup.·RESULTS:Theresultsshowedthat14daysofmonoculardefocusincreasedaxialeyelengthandrefraction,whilebFGFdeliveryinhibitedthemmarkedly.Further,itwasalsofoundthatthemonocular-7DlenscoulddecreasethelevelsoftypeIcollagen,α2integrinandβ1integrinexpressions,while,unlikePBS,bFGFincreasedthemsignificantlyincomparisontocontralateralcontroleyesandnormaleyes.CONCLUSION:bFGFcanpreventtheformationanddevelopmentofdefocusmyopiabyupregulatingtheexpressionsoftypeIcollagen,α2integrinandβ1integrin.Takentogether,ourresultsdemonstratethatbFGFpromotesscleraremodelingtopreventmyopiainguineapigs.

  • 标签: DEFOCUS MYOPIA type collagen α2
  • 简介:AIM:ToInvestigatetheeffectsoftransforminggrowthfactorβ2(TGF-β2)andconnectivetissuegrowthfactor(CTGF)ontransdifferentiationofhumanlensepithelialcells(HLECs)culturedinvitroandsynthesisofextracellularmatrix(ECM).METHODS:HLECsweretreatedwithTGF-β2(0,0.5,1.0,5,10μg/L)andCTGF(0,15,30,60,100μg/L)fordifferenttimes(0,24,48,72h)invitroandtheexpressionofα-smoothmuscleactin(α-SMA),themaincomponentoftheextracellularmatrixtypeⅠcollagen(Col-1)andfibronectin(Fn)weremeasuredbyusingreal-timepolymerasechainreaction(PCR)andwestern-blot.RESULTS:TGF-β2andCTGFsignificantlyincreasedexpressionofα-SMAmRNAandprotein(P<0.05,P<0.001),FnmRNAandprotein(P<0.001),Col-1mRNAandprotein(P<0.001).TGF-β2couldinduceHLECsexpressionofCTGFmRNAandproteinindosedependentmanner(P<0.05,P<0.001).TGF-β2andCTGFcouldinduceHLECstoexpressα-SMA,FnandCol-1intime-dependentmanner.EachtimeofTGF-β2andCTGFinducedHELCsexpressionofα-SMA,Fn,Col-1mRNAandproteinwassignificantincreasecomparedwithcontrol(P<0.05,P<0.001).CONCLUSION:TGF-β2andCTGFcouldinduceHLECsepithelialmesenchymaltransitionandECMsynthesis.

  • 标签: transforming GROWTH FACTOR β2 CONNECTIVE tissue
  • 简介:AIM:ToIntroduceanewspecializedvisualacuitychartforamblyopicchildrenaged3-5yearsoldanditsclinicalapplications.METHODS:ThenewvisualacuitychartandnotationsweredesignedbasedonWeber-Fechnerlaw.Theoptotypeswereredagainstawhitebackgroundandwerespeciallyshapedfourbasicgeometricsymbols:circle,square,triangle,andcross.Aregulargeometricprogressionoftheoptotypesizesanddistributionwasemployedtoarrangein14lines.Theprogressionrateoftheoptotypesizebetweentwolineswas1.2589andthetestingdistancewas3m.VisualacuityscorecouldberecordedaslogMARnotationordecimalnotation.Agestratifieddiagnosticcriteriaforamblyopiaestablishedbyconsensusstatementondiagnosisofamblyopia(2011)amongmembersoftheStrabismusandPediatricOphthalmologyGroup,OphthalmologySociety,ChineseMedicalAssociation(SPOGOSCMA)wereillustratedinthenewvisualacuitychart.RESULTS:Whenassessingvisualacuityinchildrenaged3-5yearsold,thisnewvisualacuitychartthatconsistsoffoursymmetricalshapes(triangle,square,cross,andcircle)overcameaninabilitytorecognizethelettersofthealphabetanddifficultiesindesignatingthedirectionofblackabstractsymbolssuchasthetumbling’E’orLandolt’C’,whichthesubjectswerepronetoloseinterestin.Thevisualacuityscoremayberecordedindifferentnotations:decimalacuityandlogMAR.Thesetwonotationscanbeeasilyconvertedeachotherintheneweyechart.Themeasurementsofthisnewchartnotonlyshowedasignificantcorrelationandagoodconsistencywiththeinternationalstandardlogarithmicvisualacuitychart(r=0.932,P<0.01),butalsoindicatedahightest-retestreliability(89%ofretestscoreswerewithin0.1logMARunitsoftheinitialtestscore).CONCLUSION:Theresultsofthisstudysupportthevalidityandreliabilityofdistancevisualacuitymeasurementsusingtheneweyechartinchildrenaged3to5yearsoverawiderangeofvisualacuities,andtheneweyechartisgreatforearl

  • 标签: amblyopic CHILDREN Weber-Fcchner LAW INTERNATIONAL standard