简介：

简介：Objective:Todetectsuperoxideanion(O-2)signalsintheheart,liver,lungandkidneytissuesafterburns.Methods:Twenty-fourmaleratswererandomizedinto4groups.Theratsofexperimentalgroupswereimmersedin100℃waterfor15secondsand25%third-degreeburnwascreated.Thoracotomyorlaparotomywasperformedat5,10,15,20and30minutesafterburn,andspecimensoftheheart,lung,liverkidneywereobtainedforburnedrats.Thespecimenswerethenpreservedinliquidnitrogenforcryo-preservationanddetectedimmediatelyusingEPR.Results:ThesignalsofsuperoxideOradicalappearedintheheart,lung,liverandkidneyspecimens10-15minutesafterburn.Conclusions:Thereisadirectevidenceofoxygenfreeradicals(OFRs)injurytovisceraofburnedratsbetween10-15minutesafterburn.

简介：Objective:Tofurtherinvestigatetheosteogenicpotentialofrabbitmarrowstromalstemcellsculturedinvitro.Methods:Rabbitmarrowstromalstemcellswereisolatedbydensitygradientcentrifugationmethodandamplifiedintheflasks,usingtheosteogenicinducingconditions(OGC)astheculturemedia.Theosteogenicpotentialofmarrowstromalstemcellswereinvestigatedbymeansofbone-seekingfluorescenc(tetracycline)labeling,AlizarinredS(ARS)staining,Alcianblue-Siriusred(AS)staining,andscanningelectronmicroscope.Results:Afterbeingpassaged,themarrowstromalstemcellsincreasedinnumber,becameconfluentandformedmulti-layerstructure.Thestromalstemcellsexcretedinnumerabletinygranules,heapinguponthecellbodyandmerginggraduallyintofoggysubstances.Thesefoggysubstanceskeptonenlargingandformedround,oval,orflake-likenodules.Thesenodulesrevealedbrightgoldenyellowfluorescenceunderfluorescencemicroscopewhenlabeledwithtetracycline.HistochemicalstudywithspecificnewbonestainingwithARSrevealedpositivecalciumreaction,bothdenotingthattheywerenewlyformedbonetissues.AftertheywerestainedwithAS,collagenandacidmucopolysaccharidewereshown.Underscanningelectronmicroscope,threetypesofcellswithdifferentconfigurationswerefound.Theywereglobularcells,spindle-shapedcellsandpolygonalorpolygonalcells.Granuleswereexcretedfromthecellsandheapeduponthecellbody.Needle-shapedandirregularlyrectangularcrystalsalsoappearedandagglomeratedwiththegranulestoformnodulesandtrabecula-likeorflake-likestructures.Conclusions:Sequenceofeventsofboneformationbyrabbitmarrowstromalstemcellsculturedinvitroisfullydepictedandconfirmed,whichprovidesthefoundationforfurtherinvestigatingthemechanismsofosteoblastdifferentiationfrommarrowstromalstemcellsandthepossibleapplicationinorthopaedics.