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: Cytomegalovirus ( CMV ) shedding or serological rises in antibody titer , or both occurred in 78 % of cyclosporine patients and 76 % of Aza patients .
### Output Text:
Cytomegalovirus ( CMV ) shedding or serological rises in antibody titer , or both occurred in 78 % of <span class="chemical">cyclosporine</span> patients and 76 % of <span class="chemical">Aza</span> patients . 