简介:本文阐述了基于形变模型(DeformableModels)的LevelSet分割方法的基本原理及其特点,介绍了在图像域的实现方法,实现并改进了基于该模型的NarrowBand快速算法.该算法的基本流程是:先在需要分割的目标内或外给定一封闭的初始曲线,通过Gaussian滤波后计算图像的梯度,最后通过NarrowBand算法完成轮廓线的抽取.该算法应用于医学CT/MRI影像以及显微图像的目标分割中,取得了较好的实验结果,证明该方法非常适合于对具有分支、突触以及拓扑结构变化的目标进行快速精确分割.文中给出了算法实现的基本流程、相关参数的选取准则和部分实验结果.实验发现算法中涉及的参数对提取的轮廓线的精确和光滑程度有较大影响.
简介:Objective:Todetecttheconcentrationofmonocytechemoattractantprotein-1(MCP-1)intheserumofpatientswithincompletespinalcordinjuryandevaluateitsrelationwiththepathologicclassificationofthespinalcordinjury.Methods:MCP-1concentrationintheserumofpatientswithincompletespinalcordinjury(iSCI),singlespinecompressionandhealthysubjectsweredetectedbyELISA,respectivelyinthepresentstudyandthemagneticresonanceimagingdataofthesepatientswerestudiedatthesametimeonablindbase.Results:SerumlevelofMCP-1iniSCIpatientswas428pg/ml±11pg/mlbyELISA,whichwashigherthanboththatofthepatientswithsinglespinecompressionandofcontrols,withtheconcentrationof184pg/ml±21pg/mland124pg/ml±15pg/ml,respectively.Therewassignificantdifferencebetweenanytwogroups(P<0.01).iSCIpatientswithnormalMRIshowedalowerserumlevelofMCP-1as312pg/ml±30pg/ml.Pathologicalclassificationofspinalcordedemaandhematomacorrespondedto390pg/ml±16pg/mland508pg/ml±24pg/mlintheconcentrationofMCP-1.Conclusions:MCP-1mayinducesecondaryinflammatoryresponsebyrecruitinginflammatorycellstotheinjurysiteandthusaffecttheprognosisofspinalcordinjury.