1·Tunica adventitia: entirely made of connective tissue.
外膜：完全由结缔组织构成。
2·Inadequate cell nutrition around vessels causes degeneration of tunica adventitia.
血管周围细胞的营养不足，引起外膜的变性。
3·The oviduct ampulla and isthmus were composed of mucous layer, tunica muscularis and adventitia.
壶腹部和峡部均由黏膜层、肌层和外膜构成。