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: Compared with wild - type mice , transgenic mice exhibited higher survival rate as well as more preserved left ventricular function and cardiac expression of alpha - sarcomeric actin .
### Output Text:
Compared with wild - type mice , transgenic mice exhibited higher survival rate as well as more preserved left ventricular function and cardiac expression of alpha - sarcomeric actin . 