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: Myopathy due to lack of vitamin E and myopathy induced by certain viruses have much in common anatomically and pathologically with the human form .
### Output Text:
Myopathy due to lack of <span class="chemical">vitamin E</span> and myopathy induced by certain viruses have much in common anatomically and pathologically with the human form . 