Assertion: periosteum's cell | /r/AtLocation | the epithelium
Facets:
value: usually
type: TEMPORAL
Source sentences:
text: Mucus-secreting cells or glands are usually present in the epithelium but may be absent.
text: Mucus-secreting cells or glands are usually present in the epithelium but may be absent.
text: Mucus-secreting cells or glands are usually present in the epithelium but may be absent.