鼓管 鼓室 舌 扁桃体窝 咽 (2 Second pharyngeal pouch distal portion: obliterated remaining part proliferate and form primordium of the palatine tonsil
② Second pharyngeal pouch: ---distal portion: obliterated ---remaining part proliferate and form primordium of the palatine tonsil
Third pharyngeal pouch -dorsal portion: differentiates into inferior parathyroid gland ventral part: cells differentiates and form two cell cords fuse with each other behind the thorax to give rise to the promordium of the thymus 舌 甲状腺原基 下甲状旁腺原基 上甲状旁腺原基
③ Third pharyngeal pouch: ---dorsal portion: differentiates into inferior parathyroid gland ---ventral part: cells differentiates and form two cell cords, fuse with each other behind the thorax to give rise to the promordium of the thymus
4 Fourth pharyngeal pouch ---dorsal portion: forms superior parathyroid gland ventral portion; degenerates 5 Fifth pharyngeal pouch gives rise to the ultimobranchial body, immigrate into thyroid and differentiate into parafollicular cells 甲状腺原基 下甲状旁腺原基 上甲状旁腺原基
④ Fourth pharyngeal pouch: ---dorsal portion: forms superior parathyroid gland ---ventral portion: degenerates ⑤ Fifth pharyngeal pouch: ---gives rise to the ultimobranchial body, immigrate into thyroid and differentiate into parafollicular cells
第1咽囊 甲状舌管动 第2咽囊 扁桃体窝 甲状 第3咽囊 下甲状旁腺原基 第4咽囊 上甲状旁腺原基 后魑体 development of thyroid gland thyroid primordium by the 4 th week endodermal proliferation of the floor of primitive pharynx, then descends in front of the primitive pharynx as a bilobed diverticulum thyroglossal duct: a narrow canal connecting primitive pharynx with thyroid primordium by the 6th week, becomes solid and disappears
*development of thyroid gland ---thyroid primordium: by the 4th week, endodermal proliferation of the floor of primitive pharynx, then descends in front of the primitive pharynx as a bilobed diverticulum ---thyroglossal duct: a narrow canal connecting primitive pharynx with thyroid primordium, by the 6th week, becomes solid and disappears
第1咽囊 咽鼓管 “是第2明 甲状舌管 開扁桃体窝 甲状服 第3咽囊 下甲状旁腺原基 廣腺原基 M 第4咽囊 颈窦 第5咽囊 foramen caecum thyroglossal cyst and fistula: a cystic remnant of the thyroglossal duct, may be found at any point along the migratory path followed by the thyroid gland; sometimes a thyroglossal cyst is connected to the outside by a fistulous canal, called thyroglossal fistula
---foramen caecum: ---thyroglossal cyst and fistula: a cystic remnant of the thyroglossal duct, may be found at any point along the migratory path followed by the thyroid gland; sometimes a thyroglossal cyst is connected to the outside by a fistulous canal, called thyroglossal fistula