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 : Since 2005 , the 10 - min loading dose of our dexmedetomidine protocol increased from 2 to 3 microg . kg ( - 1 ) , and the infusion rate increased from 1 to 1 . 5 to 2 microg . kg ( - 1 ) . h ( - 1 ) .
### Output Text:
RESULTS : Since 2005 , the 10 - min loading dose of our <span class="chemical">dexmedetomidine</span> protocol increased from 2 to 3 microg . kg ( - 1 ) , and the infusion rate increased from 1 to 1 . 5 to 2 microg . kg ( - 1 ) . h ( - 1 ) . 