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: ATPase staining of the diaphragm , scalenus medius , and gastrocnemius showed type IIb fiber atrophy in the steroid groups and also diaphragmatic type IIa atrophy with T , whereas histologic examinations revealed a normal muscular pattern with absence of necrosis .
### Output Text:
ATPase staining of the diaphragm , scalenus medius , and gastrocnemius showed type IIb fiber atrophy in the <span class="chemical">steroid</span> groups and also diaphragmatic type IIa atrophy with <span class="chemical">T</span> , whereas histologic examinations revealed a normal muscular pattern with absence of necrosis . 