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1、Br.J.Cancer(1986),53,385-391ThesignificanceofelectronspinresonanceoftheascorbicacidradicalinfreezedriedhumanbraintumoursandoedematousornormalperipheryH.W.MuellerandS.TannertDepartmentofClinicalNeurochemistry,NeurosurgicalUniversityClinic,Justus-Liebig-University,6300Giessen,FR
2、G.SummaryTheESRspectrum,attributedtotheascorbicacid(ascorbyl)radicalandobtainedbyexposingfreezedriedmaterialtoair,cannotbeusedasprooffortheoccurranceofinvivofreeradicalreactions.Dependingonthemethodoffreezedrying,thecontentofbloodorhaemolyzedbloodisthedominantfactorincreatingh
3、igherthannormalESRsignalsinbrainorrelatedtissue.Thesefindingsexplainwhythesignal,thoughlargerinmanyhumanbraintumoursthanintheirsurroundings,isnotindicativeofmalignancy.Nodifferencesareseenbetweenoedematousandnormaltissue.Theascorbylradicalisdefinitelynotstableinaqueoussolution
4、,whichindicatesthatfreshtissuesectionscanalsonotbeusedtostudyinvivoradicalsbyESR.Freeradicalreactionshavebeenaccordedvariableoxidationparallelsandamplifiestheinvivoimportanceinnervoustissuepathologicalprocessessituation.Thiswasreasonenoughtotestthesuchasoedema(Chanetal.,1984),
5、ischemiatechniqueforitsusefulnessinelucidatingtherole(Bhakooetal.,1984),andtumour(Brauetal.,oftheascorbylradicalinhumanbraintumoursand1984).Problemswithindirecttechniques,theiroedematousperiphery.Thisradicaliscommonlyemployedinsuchstudies,havebeenespeciallyinteresting,sincelit
6、tleisknownaboutthepointedout(Halliwell,1984).Informationaboutfunctionofascorbicacidinbrain(Brauetal.,thepotentiallymostdirectapproach,electronspin1984).Asacorrelationdoesnotconstituteproof,resonance(ESR)ofradicalsintissuestemsverificationofourfindingswassoughtthroughprimarilyf
7、romnon-nervousmaterial,usuallymodelexperimentsusingnormalandoedematizedrelatedtoneoplasia(Dodd&Swartz,1984;ratbrain,humanbloodanditscomponents,andLohmann,1984).Inpractice,however,difficultiesaqueoussuspensionsofsilicagelorSephadex.areencounteredinlinkingESRoffresh,frozen,orSim
8、pleexperimentswithlyophilisatesandwithfreezedriedtissuetoinvi