简介：人的双眼是在同一个方向面向前方的,而许多动物的眼睛是在头的两侧各一个的（比如马）。正常情况下,人眼运动是协调的,所以物体在每只眼睛的中央成像。由于双眼分开一段距离，所以物体在每只眼成的像，有微小的差别。大脑将来自双眼的像融合，形成一个有深度的三维图像。这种三维视觉（又称为立体视觉或双眼视）给我们深度知觉。这使我们可以更准确的判断距离，尤其是在物体靠近我们时。试着只睁一只眼来穿针，你就会更加体会双眼视的好处。

简介：<正>在20世纪,耳鼻喉科不仅发展很快,而且对整个医学作出重大贡献:本世纪初气管食管窥镜的成功应用,创建了气管食管学;40年代双目手术显微镜问世导致耳显微外科的诞生;60年代初发现电刺激耳蜗神经引起听觉,发明人工耳蜗植入,至80年代引入微机处理,数字信息技术,产生多道程控人工

简介：AIM:Anaerobicbacteriacancauseocularinfections.WetestedtheOxyPlateTMAnaerobicSystem(OXY)toisolatepertinentanaerobicbacteriathatcancauseoculardisease.METHODS:OXY,whichdoesnotrequiredirectanaerobicconditions(i.e.bags,jars),wascomparedtoconventionalisolationofincubatingculturemediainanaerobicbags.Standardcoloniescountswereperformedonanaerobicocularbacterialisolatesunderaerobicandanaerobicconditions(anaerobicbags)usingagarmedia:1)OXY(aerobiconly),2)5%sheepblood(SB),3)Chocolate,and4)Schaedler.Thebacteriatestedwerede-identifiedocularisolatesculturedfromendophthalmitisanddacryocystitisthatinclude10Propionibacteriumacnesand3Actinomycesspecies.Thecolonycountsforeachbacteriaisolate,oneachculturingcondition,wererankedfromlargesttosmallest,andnon-parametricallycomparedtodeterminethebestculturingcondition.RESULTS:Allanaerobicconditionswerepositiveforalloftheanaerobicisolates.SBandSchaedler’sagarunderaerobicconditionsdidnotsupportthegrowthofanaerobicbacteria.SparsegrowthwasnotedonchocolateagarwithPropionibacteriumacnes.Asananaerobicsystem,SBinananaerobicbagisolatedhighercolonycountsthanOXY(P=0.0028)andchocolateagar(P=0.0028).CONCLUSION:AlthoughOXYdidnottesttobemoreefficientthanotheranaerobicsystems,itappearstobeareasonablealternativeforisolatinganaerobicbacteriafromocularsites.Theuseofanagarmediuminaspeciallydesignedplate,withouttherequirementofananaerobicbag,renderedOXYasanadvantageoverotheranaerobicsystems.

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