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Unified Medical Language System® (UMLS®)

Identifiers in the Semantic Network

The information associated with each semantic type includes:

  • A unique identifier
  • A tree number indicating its position in the `isa' hierarchy
  • A definition
  • Its immediate parent and children

The information associated with each relationship includes:

  • A unique identifier
  • The semantic type
  • A tree number
  • A definition
  • Examples
  • The set of semantic types that can plausibly be linked by this relationship.

example Semantic Network record:

STY|T020|Acquired Abnormality|A1 . 2 . 2 . 2|An abnormal structure, or one that is abnormal in size or location, found in or deriving from a previously normal structure . Acquired abnormalities are distinguished from diseases even though they may result in pathological functioning (e . g . , "hernias incarcerate") . |Abscess of prostate; Hemorrhoids; Hernia, Femoral; Varicose Veins||||| Acquired Abnormality|co-occurs_with|Injury or Poisoning|D| Acquired Abnormality|isa|Anatomical Abnormality|D| Acquired Abnormality|result_of|Behavior|D|

Last Reviewed: July 29, 2016