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: Acetylsalicylic acid , dipyridamole , and hydrocortisone all appear to have cardioprotective effects when tested in this model .
### Output Text:
<span class="chemical">Acetylsalicylic acid</span> , <span class="chemical">dipyridamole</span> , and <span class="chemical">hydrocortisone</span> all appear to have cardioprotective effects when tested in this model . 