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: Systolic BP in the PAN group was significantly high at 4 , 14 and 20 weeks , but was normal in the PAN / temocapril group .
### Output Text:
Systolic BP in the <span class="chemical">PAN</span> group was significantly high at 4 , 14 and 20 weeks , but was normal in the <span class="chemical">PAN</span> / <span class="chemical">temocapril</span> group . 