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: The effects of short - term raloxifene therapy on fibrinolysis markers : TAFI , tPA , and PAI - 1 .
### Output Text:
The effects of short - term <span class="chemical">raloxifene</span> therapy on fibrinolysis markers : TAFI , tPA , and PAI - 1 . 