e23.Development-of-the-face--neck-and-limbs颜面和四肢发生(ppt文档).ppt

组织胚胎学课件组织胚胎学课件 七年制英文医学班专用七年制英文医学班专用中国医科大学中国医科大学基础医学院基础医学院组胚组胚英文教学组英文教学组 Chapter 23 Development of the face,neck and limbs 1.Development of branchial apparatus*branchialapparatus:includingbranchialarch,branchialgroove,branchialmembraneandbranchialpouch-bythe4thweek,-frontonasalprominence:mesenchymalproliferationofventralsurfaceofbrainvesicle-heartprominence:developmentofheart-primitivepharynx:cranialpartoftheforegut-branchialorpharyngealarch:/proliferation of mesenchyma of primitivepharynx/6pairs-branchialgroove:thedepressionsbetweenbranchialarch-branchialpouch:/outpocketingsofendodermofprimitivepharynx/opposedtobranchialgroove-branchial membrane:the thin membranebetween branchial groove and branchialpouch2.Formation of face-fiveelevations/frontonasalprominence/maxillaryprominence:paired,upperbranchesoffirstbranchialarch/mandibularprominence:paired,lowerbranchesoffirstbranchialarch-stomodeum/thedepressionbetweenfiveelevations/opposedtoprimitivepharynxbybuccopharyngealmembrane,willbreakdown,then stomodeum communicates withtheforegut-nasalplacode:bythe5thweek,thickeningofectodermoflowerpartoffrontonasalprominence-nasalpit:depressionsinnasalplacode-mediannasalprominenceandlateralnasalprominence:proliferation of mesenchyme atthemarginsofthenasalplacodes-bythe5thweek,rightandleftmandibularprominencesfusetoformthelowerjawsandlips-bythe6thweek,medialnasalprominencemergetogiverisetomedianportion of the nose,middle portion ofupperlip,thephiltrum-bythe6-7thweek,maxillaryprominencefusewithmedianandlateralnasalprominencestogiverisetoupperjaw,lateralportionofupperlip,lateralportionofnose-by the end of 6th week,nasal pits deepenandfusetoformnasalsac,separatewithoralcavity by oronasal membrane,then thismembranerupturesbythe7thweek,primitivenasalcavityopensintotheoralcavity-developmentofeye:appearoneachsideoffrontonasalprominence,growinamedialdirection-developmentofear:appearonlowerportionoflowerjaw,growinaposteriorandupperdirection3.development of palate-medianpalatineprocess:orprimarypalate/bythe6thweek/mesenchymalproliferationofinner portion ofintermaxillarysegment/to give rise tosmall portion ofpalate-lateralpalatineprocess:/by8-9thweek/mesenchymalproliferation ofinnerportion of maxillaryprominence/fusewitheachother,then fuse with thetriangularprimarypalatetoformsecondarypalate-incisive foramen:the midline landmarkbetween the primary and secondarypalates-hard palate:ossification of anteriorportionofsecondarypalate-softpalate:posteriorportionofsecondarypalate-nasal septum:formed by ectodermandmesodermproliferationoffrontonasal prominence and maxillaryprominence,thengrowsdownandjoinswiththecephalicaspectofpalate4.development of neck*developedby2nd,3rd,4th,6thpairsofbranchialarches-by4-5thweek,the2ndbranchialarchgrow to caudal direction,cover the3,4,6thbranchialarches,fusewithepicardialridge-epicardialridge:upperridge of heartprominence-cervical sinus:thespacebetween2ndand3,4,6thbranchialarches-the 2nd branchial arches fuse with 3,4,6th branchial arches,cervical sinusdisappear-becomelonger:differentiateofbranchial arches,become longer ofesophagus and trachea,descent ofheartwillhelptheformationofneck5.development of limbs-upper and lowerlimbbuds:/by4thweek,formedbytheproliferationofsomaticorparietalmesoderm/mesodermalcore/ectodermalcap-circularconstriction:2,dividedtheeachlimbbudinto3segments-handandfootplates:/terminal portion of the buds becomesflattened/digitalray:thickeningportioninplates/7-8th week,the tissue between digital rayapoptosis-somaticorparietalmesodermoflimbbuds differentiate into cartilage,thenthrough endochondral ossification toformbone-somitic mesoderm differentiate intomuscleoflimbbuds6.Congenital malformations1)cleftlip:a.unilateralcleftlip:resultsfromfailureofthemaxillaryprominence to mergewithmedialnasalprominenceon theaffectedsideb.bilateralcleftlip:resultsfromfailurethe maxillary prominences to mergewith the medial nasal prominence onbothsidesc.mediancleftlip:resultsfromfailureofthemedialnasalprominencestomergeandformtheintermaxillarysegments2)oblique facial cleft:results from failureofthemaxillaryprominence to fusewiththelateralnasalprominence3)cleftpalatea.cleftoftheprimarypalateb.cleftofsecondarypalatec.cleftoftheprimaryandsecondarypalates4)cervical cyst and cervical fistula:cervical cyst results from failure ofatresiaofcervicalsinus,ifcervicalcystopen to cavity of pharynx or bodysurface,calledcervicalfistula5)abnormalitiesoftheextremities:a.reductiondefect:meromelia,phocomeliaandameliab.duplicationdefect:polydactylyc.dysplasia:sirenomelusandsyndactyly