This is normal esophageal squamous mucosa at the left, with underlying submucosa containing mucus glands and a duct surrounded by lymphoid tissue. The muscularis is at the right.

• 左侧是正常食管的复层鳞状上皮,其下是粘膜下层,含有粘液腺和一导管,导管周围有淋巴组织围绕,右侧是肌层。