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: RESULTS : Records of 262 patients who were taking hydroxychloroquine and screened in the Department of Ophthalmology were reviewed .
### Output Text:
RESULTS : Records of 262 patients who were taking <span class="chemical">hydroxychloroquine</span> and screened in the Department of Ophthalmology were reviewed . 