| Namespace | MPheno.ontology | Obsolete | false |
| description | complete absence or loss of the dense region demarcating the thymus medulla from the surrounding cortex that is characterized by numerous blood vessels (predominantly arterioles) with some perivascular connective tissue, mature and immature T lymphocytes, dendritic cells, variable numbers of perivascular B-lymphocytes and plasma cells; normally, this is the site of entry of bone marrow stem cells and exit of mature, functional T cells |
