In the sentence extracted from biomedical literature, identify all the chemical entities. The required answer format is the same sentence with HTML <span> tags to mark up specific entities. 
### Entity Markup Guides:
Use <span class="chemical"> to denote a chemical.

### Input Text: BACKGROUND : Markers of fibrinolysis , thrombin - activatable fibrinolysis inhibitor ( TAFI ) , tissue - type plasminogen activator ( tPA ) , and plasminogen activator inhibitor - 1 ( PAI - 1 ) levels were studied for the evaluation of short - term effects of raloxifene administration in postmenopausal women .
### Output Text:
BACKGROUND : Markers of fibrinolysis , thrombin - activatable fibrinolysis inhibitor ( TAFI ) , tissue - type plasminogen activator ( tPA ) , and plasminogen activator inhibitor - 1 ( PAI - 1 ) levels were studied for the evaluation of short - term effects of <span class="chemical">raloxifene</span> administration in postmenopausal women . 