皮肤的构造与功能专家讲座

皮膚構造與功效高榮皮膚科主治醫師陳雅惠皮肤的构造与功能专家讲座第1页LookatyourskinMorethanacoveringAvitalorgan,complexstructureDevelopfromthesametissuesasthebrain皮肤的构造与功能专家讲座第2页SkinfactsSurfacearea:about2500cm²inanewbornbaby,18000cm²inanadult.About6-16%ofbodyweight:average3kginawoman,perhaps5kginaman.thickness:variesonsites.thinnestontheeyelidsandthickestonthepalmsandthesoles.皮肤的构造与功能专家讲座第3页Threelayers:

epidermis,dermis,subcutaneousfat皮肤的构造与功能专家讲座第4页EpidermisThickness:35-50m,only20maroundeye,thickeronthepalmandsole(mm)oxygenandnutrientsfromthedermisTranslucentBasementmembraneReteridges皮肤的构造与功能专家讲座第5页Epidermis-2AllkeratinocytesoriginatefrombasallayerMoveupward,changeshapeandlossnucleus,produceskinprotein(keratin)andfat(sphigolipid,ceramide)Corneocytes:deadResisttoinjurykeepwater皮肤的构造与功能专家讲座第6页Epidermis-2Desquamation(squames)Renewcycle:about30daysPsoriasis:4-7timesfasterSpeedup:sunburn,peelaging皮肤的构造与功能专家讲座第7页Epidermis-3Amodelof“bricksandmortar”Corneocytes,desmosomes,naturalfatupto15%ofthestratumcorneumconsistsofwater.TEWL(transepidermalwaterloss)皮肤的构造与功能专家讲座第8页Dermis3000mthick,keepresilienceandsuppleContainbloodvessels,nerves,hairrootsandsweatglandsFibroblastsmakecollagenandelastinGroundsubstance:glycoprotein(hyaluronicacid,chrondroitinsulfate),maintainwater皮肤的构造与功能专家讲座第9页Dermis-2Collagen:75%Elasticfibers:Elastin,5%StretchmarksWoundrepairAcrosslines,deep,largeGranulationtissueHypertrophicscarKeloid

皮肤的构造与功能专家讲座第10页SubcutaneousfatlayerAdipocytes,largervesselsandnervesDepthdiffersfromsiteandindividualCushing,conservebodyheatstorefat:women(buttocksandthighs),men(abdominalwall)cellulite皮肤的构造与功能专家讲座第11页SebaceousglandsPartofhairfolliclesineverypartexceptpalmandsoleSebum:pH=4.2-5.6,protectskinandlubricatehairshaftMixtureofsebumandsweat:naturaloil-in-wateremulsion,killsomefungiInfluencebymalehormonemostsensitiveatpubertyonfaceandtrunk皮肤的构造与功能专家讲座第12页EccrineglandsEmptydirectlyontotheskinineverypartexceptlipsandglanspenisProducesweat:mixtureofwaterandsaltsRegulatethebodytemperatureRemovewaste皮肤的构造与功能专家讲座第13页ApocrineglandsInaxillaryandgenitalarea,breastDecapitationsecretionDependentonsexhormoneGermsgrowinmoistareaproducebodyodor皮肤的构造与功能专家讲座第14页HairsVellushairs:mostskin,attachedtotinymusclesinthedermis,“goosebumps”Terminalhairs:scalp,eyelids,eyebrows,Beard,chest,armandleg:duetomalehormoneCuticle,cortex,medulla皮肤的构造与功能专家讲座第15页BloodvesselsSupplytheskinandappendagesRegulatebodytemperatureSympatheticnervemakeitconstriction;parasym.nerve,dilatation.皮肤的构造与功能专家讲座第16页NervesAutonomicnerves:vessels,sweatglands,smoothmusclesSensorynervesSubepidermalplexusMerckelplexus皮肤的构造与功能专家讲座第17页Functionsoftheepidermisprotectingthebodyfromtheenvironment,particularlythesunpreventingexcessivewaterlossfromthebodyprotectingthebodyfrominfection.皮肤的构造与功能专家讲座第18页Functionsoftheepidermis-1ultravioletradiationcreatefreeradicalsprotectingthenucleiofthecellsintheepidermisandthecollagenofthedermisPartisreflectedbythestratumcorneumattheskinsurfacepartisabsorbedbythemelaninintheepidermalcellssomeisscatteredwithintheskin皮肤的构造与功能专家讲座第19页Functionsoftheepidermis-2Water:70-75%oftheweightofthebasallayer,butonly10-15%ofthestratumcorneum.Ifbelow10%,itbecomesdry,lessflexibleandpronetodamage,breakdownandinfection.Theepidermisasawholeisabout35mthickwhendry,swellto48monfullhydration.皮肤的构造与功能专家讲座第20页Functionsoftheepidermis-3HydrationcomponentsofStratumcomponent1.Keratin2.acornifiedenvelopeofcorneocytes3.LipidsLinoleicacid(diet),ceramides4.naturalmoisturisingfactors(NMF)Aminoacids(40%),pyrrolidonecarboxylicacid(12%),lacticacid(12%),urea(8%),salts(18%),unidetifiedcompounds(10%)5.desmosomes6.enzymes皮肤的构造与功能专家讲座第21页Functionsoftheepidermis-4ThreelevelagainstinvasionbymicroorganismNaturallayerofoil-in-wateremulsiononskinStratumcorneumWhitebloodcellsinskinDefenseconcernschemicalsLangerhanscellssemipermeable皮肤的构造与功能专家讲座第22页Functionsofthedermisprotectiontothebodyfrombumpsandknocksprovideoxygenandnutrientsremovewasteproductsofmetabolismfromtheepidermis,whicharealsocarriedawayinthebloodprovideshapeandformtothebody,byholdingallitsstructurestogethercontributingtoskincolor,partic