Thaum lub lim tiam thib kaum , cov txheej txheem inter-maxillary yuav tsim tus choj qhov ntswg thiab philtrum ntawm daim di ncauj. Cov ntaub so ntswg ntawm 1st (mandibular) pharyngeal arch pharyngeal arch Cov ceg ntoo yog embryologic cov qauv uas txhim kho mus rau hauv cov qauv hauv cov neeg laus Lo lus "branchial" muab los ntawm Latin "branchia," lub ntsiab lus gills, thiab yog siv los piav txog kev loj hlob ntawm ntau hom ntses thiab amphibia. https://www.ncbi.nlm.nih.gov › books › NBK538487
Embryology, Branchial Arches - StatPearls - NCBI Bookshelf
keeb kwm los ntawm mesoderm thiab neural crest.
philtrum tsim li cas?
Nyob rau hauv tib neeg, lub philtrum yog tsim qhov twg cov txheej txheem nasomedial thiab maxillary ntsib thaum lub sij hawm embryonic txoj kev loj hlob. Thaum cov txheej txheem no tsis ua tiav tag nrho, daim di ncauj cleft yuav tshwm sim.
Puas thaum ntxov embryonic lub ntsej muag kev loj hlob?
Lub ntsej muag ntawm tib neeg lub embryo txhim kho sai heev thaum cev xeeb tub, pib ntawm plaub lub lis piam tom qab xeeb tub. Ntau yam ntawm cov qauv ntawm lub ntsej muag yog los ntawm ib pawg ntawm cov hlwb hu ua cranial neural crest cells. … Ua ke, cov khaubncaws sab nraud povtseg tsim cov qauv zoo li oval-zoo li disc.
Lub lim tiam twg ntawm kev txhim kho ua ob sab qhov ntswg Placodes tshwm sim?
Ntawm kawg ntawm lub lim tiam plaub, ob ectodermal thickenings: nasal placodes, tshwm sim ntawm cov txheej txheem frontonasal.
daim di ncauj sab sauv tsim li cas?
Qhov tshwm sim: Qhov maxillary prominence thiab medial nasal prominence daim ntawv daim di ncauj sab sauv, whereas lub lateral nasal, medial nasal, thiab maxillary prominences tsim lub qhov ntswg. Muaj fusion ntawm maxillary prominence nrog lub qhov ntswg qhov ntswg. Qhov kev sib txuas no tsis tau piav qhia yav dhau los.
