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Production d'une ptéryle supplémentaire chez l'embryon de Poulet: II. Analyse expérimentale
[摘要] 1.1.Variouskindsofobjectswereimplantedintherightpresumptiveareaoftheventralbodywallof2-daychickembryos(6–27pairsofsomites).2.2.Theimplantationmayresultintheformationofasupernumeraryfeathertract(pteryla),generallylocatedinthemid-ventralapteriuminfrontoftheumbilicus.3.3.Thevariouslivingorinanimateimplantsdonotdisplaythesamemorphogenicpotency;thelatterisdefinedastheproportionofembryosbearinganextrafeathertractandbythenumberoffeathergermspersupernumerarypteryla.Amonglivingimplants,theneuraltubeismoreactive(49%and41feathergerms)thananyoftheotheraxial(26%and32feathergerms)ornonaxialorgans(31%and31feathergerms).4.4.Amonginanimateimplants,agarcontainingbrainextract(41%and40feathergerms)isalmostasactiveasthelivingneuraltube.Paraffinhasalessermorphogeneticactivity(26%and28feathergerms).Othersubstances,suchasMilliporefilters,polyethylene,Teflon,oraluminum,areinactiveandneverinduceanextrapteryla.5.5.Aminimumcontactof16hoursbetweenactiveimplantsandprospectiveventraltissuesisrequiredfortheformationofanextrapteryla.Ashortcontactof6hoursisneverfollowedbytheproductionofsupernumeraryfeathergerms.6.6.Theactiveimplantsexertarepulsiveactiononthecells.Inthisway,abnormalbutconstantrelationshipsareestablishedbetweenthevariouslayersofthesomatopleureandthesplanchnopleure.Enterocutaneousfistulasarefrequent.Considerablelengthsoftheectodermmaybefusedtotheendoderm;inthesamewaythesplanchnicmesodermmaybefusedtothesomaticmesoderm.7.7.Theproportionofembryoswithsuchfusedareas(48%inthecaseofagarcontainingbrainextract;24%inthecaseofparaffin)issimilartotheproportionofembryosbearinganextrapterylaaftertheimplantationofeithersubstance,respectively.Wesuggesttheexistenceofacausalrelationshipbetweenthehistologicaldisordersoftheprospectivemid-ventralapteriumanditsabilitytoformfeathers.
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[效力级别]  [学科分类] 生物科学(综合)
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