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: Epsilon aminocaproic acid ( EACA ) has been used to prevent rebleeding in patients with subarachnoid hemorrhage ( SAH ) .
### Output Text:
<span class="chemical">Epsilon aminocaproic acid</span> ( <span class="chemical">EACA</span> ) has been used to prevent rebleeding in patients with subarachnoid hemorrhage ( SAH ) . 