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: These results suggest that antithrombosis of TET and FAN in mice may be mainly related to the antiplatelet aggregation activities .
### Output Text:
These results suggest that antithrombosis of <span class="chemical">TET</span> and <span class="chemical">FAN</span> in mice may be mainly related to the antiplatelet aggregation activities . 