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: Gemcitabine and cisplatin have activity in HL , non - overlapping toxicity with first - line chemotherapeutics , and may be delivered in an outpatient setting .
### Output Text:
<span class="chemical">Gemcitabine</span> and <span class="chemical">cisplatin</span> have activity in HL , non - overlapping toxicity with first - line chemotherapeutics , and may be delivered in an outpatient setting . 