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: A lower risk of renal impairment was seen in both groups with beta - blocker therapy ( RR 0 . 70 , 95 % CI 0 . 57 - 0 . 85 ) and higher baseline ejection fraction ( RR 0 . 93 per 5 % increment , 95 % CI 0 . 91 - 0 . 96 ) .
### Output Text:
A lower risk of renal impairment was seen in both groups with beta - blocker therapy ( RR 0 . 70 , 95 % CI 0 . 57 - 0 . 85 ) and higher baseline ejection fraction ( RR 0 . 93 per 5 % increment , 95 % CI 0 . 91 - 0 . 96 ) . 