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: Fourteen of 84 ( 17 % ) patients had symptoms and signs consistent with CYA cardiotoxicity within ten days of receiving 1 to 4 doses of CYA .
### Output Text:
Fourteen of 84 ( 17 % ) patients had symptoms and signs consistent with <span class="chemical">CYA</span> cardiotoxicity within ten days of receiving 1 to 4 doses of <span class="chemical">CYA</span> . 