part of part_of develops from primordium 原基 immune system 免疫系统 pharyngeal gland 咽腺 pharyngeal epithelium 咽上皮 thymus primordium 胸腺原基 A small outgrowth of the pharyngeal epithelium that is the site of lymphocyte cell production[ZFA]. [PMID]. thymic primordium thymic rudiment 是淋巴细胞生成部位的咽上皮的小生长物[ZFA]。 [PMID]。 胸腺原基(thymic primordium) 胸腺原基(thymic rudiment) early pharyngeal endoderm 早期咽内胚层