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: Bradycardia induced by biperiden is attributed to the speed of injection and to a dose - related dual effect of atropine - like drugs on muscarine receptors .
### Output Text:
Bradycardia induced by <span class="chemical">biperiden</span> is attributed to the speed of injection and to a dose - related dual effect of <span class="chemical">atropine</span> - like drugs on <span class="chemical">muscarine</span> receptors . 