Assertion: stem cell's tissue | /r/HasProperty | need
Facets:
Source sentences:
text: Moreover, most tissues are a complex mix of different cell types, and there is a need for the generation of autologous stem cells that can directly contribute to repair and regeneration of multiple cell types in a context-dependent manner.
text: Normal cells undergo a process called angiogenesis only as part of normal growth and development and when new tissue is needed to repair damaged tissue.