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: Significant increases in certain factors of the blood coagulation and fibrinolysin systems ( factors I , II , VII , VIII , IX , and X and plasminogen ) were observed in the treated groups .
### Output Text:
Significant increases in certain factors of the blood coagulation and fibrinolysin systems ( factors I , II , VII , VIII , IX , and X and plasminogen ) were observed in the treated groups . 