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: Doses were set at 0 . 3 , 3 . 0 and 30 . 0mg / kg for piroxicam and 0 . 2 , 2 . 0 and 20 . 0mg / kg for DFU .
### Output Text:
Doses were set at 0 . 3 , 3 . 0 and 30 . 0mg / kg for <span class="chemical">piroxicam</span> and 0 . 2 , 2 . 0 and 20 . 0mg / kg for <span class="chemical">DFU</span> . 