简介:Inordertounderstandthedevelopmentofstemcellsintospecializedmaturecellsitisnecessarytostudythegrowthofcellsinculture.Forthispurposeitisveryusefultohaveanefficientcomputerizedcelltrackingsystem.Inthispaperaprototypesystemfortrackingneuralstemcellsinasequenceofimagesisdescribed.Inordertogetreliabletrackingresultsitisimportanttohavegoodandrobustsegmentationofthecells.Toachievethiswehaveimplementedthreelevelsofsegmentation.Theprimarylevel,appliedtoallframes,isbasedonfuzzythresholdandwatershedsegmentationofafuzzygrayweighteddistancetransformedimage.Thesecondlevel,appliedtodifficultframeswherethefirstalgorithmseemstohavefailed,isbasedonafastgeometricactivecontourmodelbasedonthelevelsetalgorithm.Finally,theautomaticsegmentationresultonthecrucialfirstframecanbeinteractivelyinspectedandcorrected.Visualinspectionandcorrectioncanalsobeappliedtootherframesbutthisisgenerallynotneeded.Forthetrackingallcellsareclassifiedintoinactive,active,dividingandclusteredcells.Differentalgorithmsareusedtodealwiththedifferentcellcategories.Aspecialbacktrackingstepisusedtoautomaticallycorrectforsomecommonerrorsthatappearintheinitialforwardtrackingprocess.
简介:Inarecentstudy,researcherstookadultfemaleFischerratsandperformedaspinalcordtransectionontheminanattempttostudythegrowthoftransplantedearly-stageneurons.Whensuchearly-stageneuronsweretransplantedintoratssufferingfromparalysis,remarkableaxonalgrowthwasobserved.Theresultwasmanynewrelaycircuitsthatformed,whichsignificantlyimprovedfunction,
简介:Theresearchgroupwasinterestedinthetherapeuticpotentialoflimbalfibroblasts,whicharepre-sentinthecorneallimbus.Recently,inmuchstemcellresearch,researchersandadvocatesarestress-ingtheimportanceofutilizingcellsfromthenichewhichtheywilltarget.Thismeans,thatadiposetissueandbonemarrowderivedstemcells,arelikelynotappropriateandevendangeroustoapplyu-biquitouslyastherapiestootherpartsofthebodyincertaincases.Severalresearchgroupsandclini-caltrialshaveshownthistobethecase,includingcasesofblindness,braininflammation,anddeathasadverseevents.
简介:基于CT图像数据结合图像处理软件建立人体下颈椎C3-C7活动节段的三维有限元模型,并验证模型的有效性。选取一名健康志愿者颈椎CT数据,建立包括椎体、后部结构、终板、椎间盘、韧带和关节突等部分的下颈椎C3-C7三维有限元模型,赋予颈椎组织不同成分的材料属性,模拟人体颈椎在正常生理状态下承受扭矩载荷时,前屈、后伸、侧弯和旋转等运动情况下颈椎椎体、椎间盘和小关节的生物力学特性。颈椎C3-C7活动节段在四种工况下的活动范围与前人离体实验和有限元分析的研究结果基本吻合,颈椎椎体、椎间盘和小关节的应力分布符合其生物力学特性。下颈椎C3-C7活动节段的模拟结果符合人体的真实运动规律,为临床颈椎的生理、病理研究以及植入器械的力学性能分析奠定理论基础。