【醫(yī)學(xué)英文課件】UnderstandingRadiationTherapy

xx年xx月xx日醫(yī)學(xué)英文課件CATALOGUE目錄IntroductionTypesofRadiationSourcesofRadiationExposureRadiationEffectsontheBodyCATALOGUE目錄RadiationProtectionandSafetyMeasures01IntroductionRadiationisdefinedasthepropagationofenergythroughspaceorthroughmatter.DefinitionandNatureofRadiationRadiationisaphysicalprocessthattransfersenergyfromasourcetoanabsorberwithoutdirectcontact.Thenatureofradiationisdeterminedbyitswavelength,frequency,andenergycontent.Electromagneticradiationisatypeofwavethattravelsthroughspaceormatter.PropertiesofRadiationElectromagneticradiationhaspropertiessuchaswavelength,frequency,andamplitude.Theradisameasureoftheabsorbeddoseofradiationenergyinnon-livingmatter.Theunitofradiationmeasurementisthesievert(Sv)forgammaraysandX-rays,andtherad(rad)forneutronsandbetaparticles.UnitsofRadiationMeasurementThesievertisameasureoftheabsorbeddoseofradiationenergyinthehumanbody.02TypesofRadiation1ElectromagneticRadiation23Non-ionizingradiation:豁免輻射，不會導(dǎo)致原子或分子產(chǎn)生電離作用豁免輻射的頻率范圍包括：豁免輻射的頻率范圍包括極低頻到毫米波段，不會導(dǎo)致原子或分子產(chǎn)生電離作用豁免輻射的生物學(xué)效應(yīng)：豁免輻射的生物學(xué)效應(yīng)包括熱效應(yīng)、非熱效應(yīng)和電磁場對細胞信號轉(zhuǎn)導(dǎo)的影響Alphaparticles帶正電的氦核，由放射性原子核衰變產(chǎn)生帶負電的高能電子，也由放射性原子核衰變產(chǎn)生電磁波，波長短于0.1nm，由放射性原子核衰變產(chǎn)生不帶電的中性粒子，能量高時可由核反應(yīng)產(chǎn)生ParticleRadiationBetaparticlesGammaraysNeutronparticl…Atomicnuclei:原子核能級躍遷或裂變時釋放的高能輻射Alphaparticles:由放射性原子核衰變產(chǎn)生的氦核Betaparticles:由放射性原子核衰變產(chǎn)生的電子Gammarays:由放射性原子核衰變產(chǎn)生的電磁波Neutronparticles:中子不帶電，不受庫侖力作用，可直接穿透物質(zhì)，具有很強的致傷能力IonizingRadiation03SourcesofRadiationExposureBackgroundradiationTerrestrialradiationSolarradiationExposuretoUVradiationfromthesun,whichcancauseskincancerandotherrelatedhealtheffects.NaturalSourcesArtificialSourcesReactorsthatusenuclearfueltogenerateenergymayemitradiation,andindividualsworkinginthevicinitymaybeexposedtoradiation.RadiationdevicesIndustryResearchreactors04RadiationEffectsontheBodyLETisameasureoftheenergydepositedinmatterbyionizingradiationperunitlength.LinearEnergyTransfer(LET)LETisusedtocharacterizethequalityofionizingradiationandpredictitsbiologicaleffectiveness.BiologicalEffectsofRadiation要點三Ionizingradiationcandamagecellsandtheircomponents,leadingtocelldeathortransformation.要點一要點二RadiationcanalsodamageDNA,causingmutationsandchromosomeaberrationsthatcanleadtocarcinogenesis.Theseverityofradiationdamagedependsontheradiationtype,dose,anddurationofexposure.要點三Deterministiceffectsarethosethatoccurimmediatelyorsoonafterexposuretoradiationandincludeskinburns,nausea,vomiting,andhairloss.DeterministicEffectsHighdosesofradiationcancausedeathwithindaysorweeks,butlowerdosesmayresultinlong-termeffectssuchascataracts,infertility,andcancer.05RadiationProtectionandSafetyMeasuresSIunitsTheunitofmeasureforionizingradiationisthesievert(Sv),theunitofmeasureforequivalentdoseisthesievert(Sv),andtheunitofmeasureforeffectivedoseisthesievert(Sv).Non-SIunitsTheunitofmeasureforabsorbeddoseisthegray(Gy),theunitofmeasureforequivalentdoseistherad,andtheunitofmeasureforeffectivedoseistherad.UnitsandConversionFactorsforMeasurementofRadiationExposureRADIATIONPROTECTIONPHILOSOPHYANDPRINCIPLESRadiationsafetyandprotectionmeasuresinclude:establishingandimplementingrulesandregulationsforradiationprotection,selectingappropriateprotectiveequipmentandprotectiveequipment,selectingappropriateprotectiveequipmentandprotectiveequipment,selectingappropriateprotectiveequipmentandprotectiveequipment,selectingappropriateprotectiveequipmentandprotectiveequipment,selectingappropriateprotectiveequipmentandprotectiveequipment,selectingappropriateprotectiveequipmentandprotectiveequipment,selectingappropriateprotectiveequipmentandprotectiveequipment,selectingappropriateprotectiveequipmentandprotectiveequipment,selectingappropriateprotectiveequipmen