securities outline - new york university school of law：证券概述-纽约大学法学院

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1、3    Wounds,tissuerepairandscars  DAVIDJ.COLEMANWOUNDSWoundsandtheirmanagementarefundamentaltothepracticeofsurgery.Anyelectivesurgicalinterventionwillresultinawoundinordertogainaccesstoanddealwiththeunderlyingpathology.InthesurgeryoftraumathewoundistheprimarypathologyInbothsituationsthesurge

2、on’staskistominimisetheadverseeffectsofthewound,removeorrepairdamagedstructuresandharnesstheprocessesofwoundhealingtorestorefunction. WoundHealingInhumanregenerationislimitedtoepitheliumandtheliver;mosttissueshealbyrepairresultinginscarring.Woundhealingisthesummationofanumberofprocesseswhich

3、followinjuryincludingcoagulation,inflammation,matrixsynthesisanddeposition,angiogenesis,fibroplasia,epithelialisation,contraction,remodellingandscarmaturation(Fig.3.1).Wherewoundedgesareapposedhealingproceedsrapidlytoclosure;thisisknownashealingbyfirstintentionorprimaryhealing(Figs3.2andFig3

4、.3).Wherethewoundedgesareapart,suchaswhentherehasbeentissueloss,thesamebiologicalprocessesoccur,butrapidclosureisnotpossible.Angiogenesisandfibroblastproliferationresultintheformationofgranulationtissue.Thiscontractstoreducewoundareaandallowsepithelialisationacrossitssurfacetoachievewoundclo

5、sure.Thisisknownashealingbysecondintention(Fig3.4).Thisprocessisslower,thecontractioninvolvedmaycausecontractureandfunctionalrestriction(Fig.3.5),andtheresultanthealedsurfaceisathinlayerofepitheliumonscartissuethatmaynotprovedurableinthelongterm.Ingeneral,healingbysecondintentionwillgiveawor

6、seaestheticoutcome.Itisbecauseofthepoorfunctionalandaestheticresultsofhealingbysecondintentionthatsurgicalendeavourisusuallydirectedtowardsachievingprimarywoundhealing.ClassificationofwoundAwoundcanbecausedbyalmostanyinjuriousagentandcaninvolvealmostanytissueorstructure.Themostusefulclassifi

7、cationofwoundsfromapracticalpointofviewisthatofRankandWakefieldintotidyanduntidywounds.TidywoundsTidywoundsareinflictedbysharpinstrumentsandcontainnodevitalisedtissue(Fig.3.6);suchwoundscanbeclosedprimarilywiththeexpectationofquietprimaryhealing.Ex