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: RESULTS : CsA , FK506 and SRL all significantly decreased the GFR .
### Output Text:
RESULTS : <span class="chemical">CsA</span> , <span class="chemical">FK506</span> and <span class="chemical">SRL</span> all significantly decreased the GFR . 