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: Nimodipine treatment resulted in a statistically significant reduction in systolic BP ( SBP ) and diastolic BP ( DBP ) from baseline compared with placebo during the first few days .
### Output Text:
<span class="chemical">Nimodipine</span> treatment resulted in a statistically significant reduction in systolic BP ( SBP ) and diastolic BP ( DBP ) from baseline compared with placebo during the first few days . 