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: CONCLUSIONS : Enalapril use caused a 33 % increase in the risk of decreased renal function in patients with CHF .
### Output Text:
CONCLUSIONS : <span class="chemical">Enalapril</span> use caused a 33 % increase in the risk of decreased renal function in patients with CHF . 