学科分类
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500 个结果
  • 简介:摘要现代社会中地铁已经逐渐成为人们不可或缺交通工具之一,地铁建设工程要注意问题有很多,不仅要保障施工安全,更要确保投入使用之后安全。地铁结构中大部分都是混凝土结构,而混凝土结构本身有着十分复杂特性,会因为外界环境改变而发生变化。混凝土维护和浇筑要求技艺较高,而裂缝情况出现也是不可避免。因此如何对裂缝进行有效控制,直接关系到施工进度和施工质量,从而影响着地铁长久使用安全性。

  • 标签: 地铁施工 防水砼 裂缝 成因 对策
  • 简介:摘要混凝土是建筑工程施工中主要材料,而混凝土浇筑施工技术质量直接关系到整个工程施工质量,所以需要严格控制混凝土浇筑施工技术。根据建筑工程使用性质、结构状况以及施工现场实际情况,对混凝土浇筑施工会有一定影响,所以应该严格按照施工方案中规范要求操作,切实保证混凝土浇筑质量。严格控制混凝土浇筑每个细节,避免因为混凝土浇筑不合格而引发质量问题。文章对于建筑工程混凝土浇筑施工技术进行了分析,对于提高建筑工程施工质量具有重要意义。

  • 标签: 建筑工程 混凝土浇筑 施工技术。
  • 简介:摘要目前,大体积混凝土技术已成为我国建设工程中常用一种技术,在实际施工中,混凝土用量大,经常导致技术上会有一定困难,很容易在浇筑大体积混凝土施工中产生裂缝,而且很难控制施工质量。因此,在大体积混凝土浇筑施工中监理和管理人员要求应该严格施工质量,并做好维护工作,并根据施工中存在质量问题,采取相应预防措施,促进工程质量提高。本文主要分析了建筑工程中大体积混凝土特点,阐述了提高大体积混凝土浇筑质量施工技术措施。随着相关技术不断发展实施,中国建筑业一定能够取得长足发展,并在此基础上实现一定社会效益和经济效益。

  • 标签: 大体积 混凝土 浇筑试验工作 问题
  • 简介:摘要混凝土浇筑施工技术在建筑工程项目的施工建设中合理应用,可以提高现代城市化建设速度与质量。在混凝土浇筑过程中,要把握好浇筑过程中各个细节,如注意混凝土含气量、混凝土浇筑原材料采购和检验、避免天气因素造成混凝土变质等,以提高建筑工程施工中混凝土浇筑质量。

  • 标签: 混凝土浇筑 施工技术 建筑工程
  • 简介:混凝土浇筑施工技术是一项系统性工作,在高层建筑施工中,混凝土浇筑施工技术会对整个工程项目的施工质量产生重要影响,在高层建筑施工中混凝土浇筑施工技术对于工程质量好坏具有非常重要影响,因此一定要保证建筑结构稳定性,确保混凝土浇筑施工质量。本文首先简要介绍了混凝土浇筑施工前期准备工作,然后分析了混凝土浇筑施工技术要点,最后提出了混凝土浇筑施工中应该注意问题。

  • 标签: 高层高层建筑施工 混凝土浇筑 施工技术
  • 简介:混凝土是建筑工程施工中主要材料,而混凝土浇筑施工技术质量直接关系到整个工程施工质量,所以需要严格控制混凝土浇筑施工技术。根据建筑工程使用性质、结构状况以及施工现场实际情况,对混凝土浇筑施工会有一定影响,所以应该严格按照施工方案中规范要求操作,切实保证混凝土浇筑质量。严格控制混凝土浇筑每个细节,避免因为混凝土浇筑不合格而引发质量问题。文章对于建筑工程混凝土浇筑施工技术进行了分析,对于提高建筑工程施工质量具有重要意义。

  • 标签: 建筑工程 混凝土浇筑 施工技术。
  • 简介:摘要由于水泥混凝土路面具有稳定性好、使用寿命长、强度高、耐久性强等特点,广泛应用我国市政道路工程建设,水泥混凝土路面施工工艺简单、取材方便,并且其性质更加适用于车辆行驶,减少交通事故发生。文中着重探讨了水泥混凝土路面浇筑施工技术及质量控制措施。

  • 标签: 水泥混凝土 路面浇筑 施工 控制措施
  • 简介:摘要在现代建筑施工过程中,混凝土结构是应用最为广泛结构。作为必不可少施工环节,混凝土浇筑对于建筑整体质量和效益,都是非常重要。因此,研究建筑工程施工中混凝土浇筑施工技术具有积极理论与现实意义。本文先对混凝土浇筑施工技术进行了概述,然后,重点研究了混凝土浇筑施工技术在建筑工程施工中实践应用,以供参考。

  • 标签: 建筑工程 工程施工 混凝土浇筑施工技术
  • 简介:摘要随着我国各地高层建筑物、水利、桥梁及集中荷载物迅速涌现和发展,钻孔灌注桩施工技术因其成本低、适应性强、施工简便等优点,被广泛应用。但灌注桩属于隐蔽工程,成形后不能进行开挖验收,施工过程中也无法观察。影响灌注桩施工质量因素很多,施工中某个环节出现问题会直接影响整个工程质量和进度,甚至造成巨大经济损失以及不良社会影响。因此,在施工中要严格遵循钻孔灌注桩基础工艺流程,并采取质量控制措施,以确保顺利完成施工任务,提高工程质量,为后续施工奠定良好基础,保证建筑施工中整体结构安全。

  • 标签: 钻孔灌注桩 施工技术 质量管理
  • 简介:AIM:Toexploretheeffectofsaturatedhydrogensalineonbluelight-inducedretinaldamageinrats.·METHODS:Theretinaldamageofratswasinducedbybluelightexposurefor6hoursandexamined8hours,16hoursand24hoursaftertheexposure.OnehundredfemaleSprague-Dawleyratswererandomlydividedintofourgroups.Group1included30ratsreceivedlightexposurewithoutanyothertreatment.Group2included30ratsreceivedlightexposurewithintraperitonealinjectionofnormalsaline.Group3included30ratsreceivedlightexposurewithintraperitonealinjectionofsaturatedhydrogensaline.AndGroup4includedtheother10ratswhichdidnotreceiveanytreatment.Theamountofintraperitonealinjectionofsaturatedhydrogensalineandnormalsalinewascalculatedintheratioof1ml/100gofratweight.SpecimenswerecollectedandprocessedbyH-Estaining,ultrastructureobservation,biochemicalmeasurement.Morphologicalchangeswereobservedbylightmicroscopeandtransmissionelectronmicroscope(TEM)andtheretinalouternuclearlayer(ONL)thicknesswasmeasuredbyIPP6.0,whilethemalondialdehyde(MDA)wasmeasuredbycolorimetricdeterminationat532nm.·RESULTS:AlthoughthestructureofretinainGroup1andGroup2wasinjuredheavily,theinjuryinGroup3wasmild.ThedifferencesbetweenGroup1andGroup2werenotsignificant.ComparedwiththeratsinGroup1andGroup2,theonesinGroup3hadmoreclearlydemarcatedretinastructureandmoreorderedcellsbylightmicroscopeandTEMobservation.TheONLthicknesses(400times)offourgroupsateachtimepointexceptbetweenGroup1andGroup2weresignificantlydifferent(P<0.05).ThethicknessesoftheONLinGroup1atthreetimepointswere30.41±4.04μm,26.11±2.82μmand20.63±1.06μm,inGroup2were31.62±4.54μm,25.08±3.63μmand19.07±3.86μm,inGroup3were29.75±3.62μm,28.83±1.97μmand27.61±1.83μm.InGroup4themeanofthethicknesswas37.35±1.37μm.Astimewentby,thedamageg

  • 标签: RETINA hydrogen ANTIOXIDANTS PHOTOTOXICITY DOI.3980/j.issn.2222-3959.2012.02.07
  • 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.

  • 标签: ANAEROBIC BACTERIA BACTERIAL isolation ENDOPHTHALMITIS DACRYOCYSTITIS
  • 简介:AIM:TodiscusstheimpactofLyciumBarbarumPolysaccharide(LBP)andDanshensupurifiedfromTraditionalChineseMedicine(TCM)onvascularendothelialgrowthfactor(VEGF)ofrabbitswithretinalneovascularization.METHODS:Fortyrabbitsweredividedintonormalcontrolgroup,modelcontrolgroup,LBPgroupandDanshensugroup.Animalsinthenormalcontrolgroupwerefedinthenormaloxygenenvironment.Animalsintheotherthreegroupswereputintotheenvironmentwith70%oxygenfor5daysinordertobuildthemodelofoxygen-inducedvascularproliferationretinopathy.AndthendifferentTCMextractwasinjectedintotheabdominalcavitiesoftheseannimals.After7days,theVEGFcontentofintheserumofrabbitwasmeasuredbydoubleantibodysandwichmethod.RESULTS:DataanalysisindicatedthatVEGFcontentwasasfollows:Danshensugroupwaslowerthanmodelcontrolgroup(12.92±3.84ng/Lvs19.32±4.15ng/L,P<0.05);LBPgroupandnormalcontrolgroupwerelowerthanmodelcontrolgroup(12.92±3.84ng/L,9.26±1.61ng/Lvs19.32±4.15ng/L,P<0.01);totalbloodviscosity,plasmaviscosity,cholesterolcontent,fibrinogencontentandtriacylglycerolcontentafterperitonealinjectionofLBPandDanshensuwereobviouslylowerthanbeforeinjection.CONCLUSION:TCMextract-LBPandDanshensucanprominentlyreducethecontentofVEGFintheprocessofvascularproliferativeretinopathyofrabbit;canpreventtheoccurrenceofretinalmicrovasculardiseasebyimprovingpartialoxygen-deficientenvironmentoraffectingallkindsofnewgrowthfactor.

  • 标签: LYCIUM Barbarum POLYSACCHARIDE Dan-shensu vascular ENDOTHELIAL
  • 简介:AIM:TopresenttheresultsofimplantationofIakymenkokeratoprosthesisinfivepatientswithvascularizedcornealleukomacausedbysevereocularinjury.·METHODS:Iakymenkokeratoprosthesiswasimplantedinto5eyesof5patients:4patientsweresufferedfromchemicalburnsand1patientfromexplosiveinjury.Thepreoperativevisualacuityrangedfromlightperceptiontohandmotion.Theimplantationsurgerywascomposedoftwo-stageprocedures.Thefollow-upperiodwasfrom9monthsto11years.Theoutcomemeasureswerevisualacuity,retention,andcomplicationsofthekeratoprosthesis.·RESULTS:Visionimprovementswereachievedinmostpatients.Allkeratoprosthesiswereretainedwithinthefollow-upperiod.Cornealmeltingoccurredinonepatientandfibrousclosureinanotherpatient,bothofwhichweresuccessfullytreated.Retinaldetachmentoccurredinonepatientaftersurgery.·CONCLUSION:Iakymenkokeratoprosthesisseemstobeapromisingalternativeforthepatientswithseverecornealinjury,butfurtherinvestigationisneededtoevaluatetheroleofIakymenkokeratoprosthesis.

  • 标签: Iakymenko KERATOPROSTHESIS VISUAL REHABILITATION COMPLICATIONS
  • 简介:AIM:Toinvestigatethefrequencyofidiopathicphacodonesis(IP)insenilecataractsubjectsandtheshort-termclinicaloutcomesfollowingcataractsurgery.METHODS:Thisinstitutionalcase-controlstudyincluded1301consecutivelow-incomecataractsubjectsfromJunetoNovember2009.Anteriorsegmentwerecarefullyevaluatedwithdilatedpupilunderslit-lamp.IPwerescreenedandgradedbyacriteriasetbytheauthors.Riskfactors,surgicaloutcomes,andoperativecomplicationswereanalyzed.RESULTS:Atotalof42subjects(3.2%)withIPwerediagnosedandclassifiedasgrade1(36subjects),grade2(5subjects)andgrade3(1subject).HarderlensesandintumescentcataractswereobservedintheIPgroupthanthecontrolgroup(P<0.05).Logisticsregressiontestalsoindicatedthemainriskfactorwasthehardnessofthelens.Theincidenceofzonulardialysisduringsurgerywas23.8%(10eyes),whichwassignificantlyhigherthanthecontrols(0.7%,P<0.001).Visualoutcomesofthetwogroupswerenotstatisticallyorclinicallysignificant.CONCLUSION:HardnucleusandintumescentcataractarerelatedtoIPinsenilecataractsubjectsinQinghai,China.Withmorecarebeingtaken,grade1andsomeofthegrade2IPsubjectsachievedsimilarsurgicaloutcomesascomparedtocontrols.

  • 标签: phacodonesis LENS NUCLEUS zonular DIALYSIS
  • 简介:<正>DirSir,IamdoctorGuo-YuanYang,fromtheDepartmentofOphthalmologyofWestChinaHospitalofSichuanUniversityinChengdu,SichuanProvince,China.Iwritetopresentacasereportofposteriorlentiglobuswithcataract.

  • 标签:
  • 简介:AIM:Toevaluatechangesintheanteriorchamberdepth(ACD),crystallinelensthickness(LT)anditsrefractivepowerafterlaserinsitukeratomileusis(LASIK).·METHODS:Inallcases,thepreoperativeandpostoperativecentralACDwhichweremeasuredwithPentacam,Orbscan,IOL-MasterandA-scanultrasonography,centralcornealtruenetpowerwhichwasmeasuredwiththePentacam,OrbscanandIOL-Master,axiallength(AL)whichwasmeasuredwithIOL-MasterandLTwhichwasmeasuredwiththeA-scanultrasonographywerecomparedusingthepairedsamplettest.OcularrefractiveerrorsandlensrefractivepoweratcornealplanewerecalculatedandtheircorrelationswerealsoevaluatedbeforeandafterLASIK.RESULTS:At1weekafterLASIK,LTandcrystallinelensrefractivepoweratcornealplane(Dlens)whichwereassociatedwiththeIOL-MasterandPentacamincreasedsignificantly(P≤0.005),ACDdecreasedsignificantly(P≤0.001),butnosignificantincreasewasobservedintheDlenswhichwasassociatedwiththeOrbscan(P=0.261).SignificantcorrelationsbetweenthechangesintheocularrefractiveerrorsandDlenswhichwereassociatedwiththePentacamwereobservedat1weekand6monthsafterLASIK(P=0.028;P=0.001).CONCLUSION:LTincreasedsignificantlyafterLASIK,andthismightpartiallyleadtoACDdecrease,Dlensincreaseandasmallquantityofmyopicregression.

  • 标签: ANTERIOR CHAMBER depth CRYSTALLINE LENS thickness
  • 简介:AIM:ToexploretheinhibitoryeffectofasustainedcyclosporinA(CsA)deliverymicrosphere(CsA-MS)onposteriorcapsularopacification(PCO)inrabbiteyesaftercataractextraction.·METHODS:TwentyNewZealandwhiterabbitsacceptedcataractextractionplusintraocularlensimplantationandtheirlefteyeswereintraoperativelyinjectedCsA-MSpreparedusingpolymerpolylactioglycolicacid(PLGA)asacarrierandtheirrighteyeswereinjectedwithemptyMS.Thechangesincornea,anteriorchamberreaction,intraocularpressure,PCOandCsAconcentrationinaqueoushumorwereexaminedpostoperativelyandalltheeyeswereenucleated3monthsaftersurgeryforhistopathologicalandmorphologicalexaminationwithlightmicroscopyandelectronmicroscopy.·RESULTS:Conjunctivalhyperemia,cornealedema,intraocularpressureandanteriorchamberresponseofexperimentalandcontroleyesweresimilar,whilePCOinCsAMSinjectedeyeswasgreatlyimprovedcomparedwiththatincontroleyes.PosteriorcapsulesinCsA-MSinjectedeyesweresmoothandlensepithelialcells(LEC)didnotproliferatesignificantly(P>0.05),whileLECinposteriorcapsuleofcontroleyeshaddifferentdegreesofproliferationandcorticalregeneration.LECinCsA-MSinjectedeyeswerenotfunctionallyactiveandunderwentapoptosis,whereasLECincontroleyeswerefunctionallyactive(F-test,P=0.025).Inaddition,thecornealultrastructureshowednodifferencesbetweenCsA-MSandMSinjectedeyes.CONCLUSION:CsA-MShashighbioavailabilityinrabbiteyesandcouldinhibitpostoperativePCOoccurrenceanddevelopmentduringthestudyperiod,suggestingthatCsA-MSmaybeapromising,effectiveandsafeadministrationroutetopreventPCOinclinic.

  • 标签: SUSTAINED CYCLOSPORINE A delivery mic-rosphere POSTERIOR
  • 简介:AIM:Toinvestigatetheefficacyofnon-buckledvitrectomywithclassicalendotamponadeagentsinthetreatmentofprimaryretinaldetachment(RD)complicatedbyinferiorbreaksandproliferativevitreoretinophathy(PVR).METHODS:Aretrospective,consecutiveandcaseseriesstudyof40patientswithinferiorbreakRDandPVR≥C1wasconducted.Allpatientsunderwentastandard3-port20-gaugeparsplanavitrectomy(PPV)withgasorsiliconeoiltamponadewithoutsupplementaryscleralbuckling.Thevitreousandallproliferativemembranewerecompletelyremoved,andretinectomywasperformedwhennecessary.Themeanfollow-upwas12.5months.Theprimaryandfinalanatomicsuccessrate,visualacuityandcomplicationswererecordedandanalyzed.RESULTS:Primaryanatomicsuccessratewasachievedin35of40eyes(87.5%)andthefinalanatomicsuccessratewas100%.ThemostcommoncauseofredetachmentwasrecurrentPVR.Thebest-correctedvisualacuity(BCVA)atfinalfollow-upwasimprovedin34eyes(85%),remainedstablein1eye(2.5%),andworsenedin5eyes(12.5%).Themeanvisualacuityatfinalfollow-upwasimprovedsignificantly(P=0.000).CONCLUSION:ThisretrospectivestudyprovidesevidencethatvitrectomywithoutscleralbucklingseemedtobeaneffectivetreatmentforinferiorbreakRDwithPVR.Withcompleteremovalofvitreousandproliferativemembranesandtimingofretinectomy,theinferiorbreakswhichcomplicatedwithPVRcouldbeclosedsuccessfullywithoutadditionalscleralbuckling.

  • 标签: RETINAL DETACHMENT INFERIOR RETINAL BREAK PROLIFERATIVE
  • 简介:AIM:ToinvestigatetheeffectofY-27632onthesurvivalandneuriteoutgrowthoftheculturedretinalneurocytes.METHODS:Afterthepostnatalday2-3,Sprague-Dawleyretinalneurocyteswereculturedfor48hours,theculturemediawasreplacedwithserum-freemedia(controlgroup)andserum-freemediacontained30μmol/LY-27632(Y-27632group),andthecellswerecontinuallyculturedanother48hours.Theculturedretinalneurocyteswereidentifiedwithanti-neuronspecificenolase(NSE)immunocytochemistry.ThesurvivalstateofthosecellswasestimatedbyMTTassay,andtheneuriteoutgrowthofthosecellswasevaluatedbythecomputerizedimage-analysissystem.RESULTS:Comparedwiththecontrolgroup,theabsorbancevaluesofcellssurvivalinY-27632groupincreased12.90%and33.33%respectivelyafter72and96hoursculture.Y-27632hadnosignificanteffectonthediameterofculturedretinalneurocytes.Comparedwiththecontrolgroup,Y-27632inducedastableimprovementofneuriteoutgrowthofretinalneurocytesafter72and96hoursculture(P=0.001).CONCLUSION:Y-27632couldpromotethesurvivalandneuriteoutgrowthoftheearlypostnatalculturedretinalneurocytes.

  • 标签: Y-27632 RETINAL neurocytes cell CULTURE NEURITES
  • 简介:AIM:Toevaluatetheepidemiologic,anatomic,andclinicalfeaturesofopenglobeinjuriesinchildren.METHODS:Themedicalfilesofpatientsundertheageof16whohadbeenoperatedforanopenglobeinjuryatAkdenizUniversityHospital’sDepartmentofOphthalmologywereretrospectivelyevaluated.RESULTS:Atotalof90patientswereevaluatedinthisstudy.Amongthesepatients,26(28.9%)werefemaleand64(71.1%)weremale.Themeanageofthepatientswas7.7±4.2years.Themale/femaleratiowasobservedtoincreasewithincreasingage(P=0.006,P=7.48).Injuriesweremostlikelytooccurinspringandautumn(P=0.028).Thetimeintervalbetweentheinjuryandthesurgicalrepairwas9.36±27.4h.Forty(44.4%)oftheinjuriesoccurredinthehome,27(30%)occurredintheyard,and21(23.3%)happenedwhileplayinginthestreet.Themostcommoncausesofinjuryweresharpmetalobjects(P<0.001).Injurytothecorneaoccurredin47(52.2%)ofthepatients(P<0.001).Themostcommoncomplicationtooccurwascataractformation.Additionaloperationswerenecessaryfor37(41.1%)ofthepatients.Thefinalvisualacuitywascorrelatedwithboththeinitialvisualacuityofthewoundedeyepriortosurgeryandthelengthofthewound(P<0.001,r=0.502andP<0.001,r=-0.442,respectively).CONCLUSION:Openglobeinjuriesthataresufferedinchildhoodgenerallyoccureitherathome,intheyard,oronthestreet,withsharpmetalobjectsbeingthemostcommoncauseofinjury.Theinitialvisualacuityandthelengthofthewoundarethemostimportantdeterminantsofthefinalvisualacuity.

  • 标签: CHILDHOOD EPIDEMIOLOGY open globe INJURY PREVENTION