资源描述:
《BRS Pathology 4th ed》由会员上传分享,免费在线阅读,更多相关内容在学术论文-天天文库。
1、CHAPTER1CellularReactiontoInjuryI.ADAPTATIONTOENVIRONMENTALSTRESSA.Hypertrophy1.Hypertrophyisanincreaseinthesizeofanorganortissueduetoanincreaseinthesizeofcells.2.Othercharacteristicsincludeanincreaseinproteinsynthesisandanincreaseinthesizeornumberofintracellularorga
2、nelles.3.Acellularadaptationtoincreasedworkloadresultsinhypertrophy,asexemplifiedbytheincreaseinskeletalmusclemassassociatedwithexerciseandtheenlargementoftheleftventricleinhypertensiveheartdisease.B.Hyperplasia1.Hyperplasiaisanincreaseinthesizeofanorganortissuecause
3、dbyanincreaseinthenumberofcells.2.Itisexemplifiedbyglandularproliferationinthebreastduringpregnancy.3.Insomecases,hyperplasiaoccurstogetherwithhypertrophy.Duringpregnancy,uterineenlargementiscausedbybothhypertrophyandhyperplasiaofthesmoothmusclecellsintheuterus.C.Apl
4、asia1.Aplasiaisafailureofcellproduction.2.Duringfetaldevelopment,aplasiaresultsinagenesis,orabsenceofanorganduetofailureofproduction.3.Laterinlife,itcanbecausedbypermanentlossofprecursorcellsinproliferativetissues,suchasthebonemarrow.D.Hypoplasia1.Hypoplasiaisadecrea
5、seincellproductionthatislessextremethaninaplasia.2.ItisseeninthepartiallackofgrowthandmaturationofgonadalstructuresinTurnersyndromeandKlinefeltersyndrome.E.Atrophy1.Atrophyisadecreaseinthesizeofanorganortissueandresultsfromadecreaseinthemassofpreexistingcells(Figure1
6、-1).2.Mostoften,causalfactorsaredisuse,nutritionaloroxygendeprivation,diminishedendocrinestimulation,aging,anddenervation(lackofnervestimulationinperipheralmusclescausedbyinjurytomotornerves).3.Characteristicfeaturesoftenincludethepresenceofautophagicgranules,whichar
7、eintracytoplasmicvacuolescontainingdebrisfromdegradedorganelles.P.24.Insomeinstances,atrophyisthoughttobemediatedinpartbytheubiquitin-proteosomepathwayofproteindegradation.Inthispathway,ubiquitin-linkedproteinsaredegradedwithintheproteosome,alargecytoplasmicproteinco
8、mplex.file:///C
9、/Documents/Medicine/BRS%20Pathology%204th%20ed/Chapter%201%20-%20Cellular%20Reaction%20to%20Injury.htm[16/04/201112