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: The dyskinetic parkinsonian patients exhibited a pattern of response which was markedly different from those of the normal subjects and non - dyskinetic parkinsonian patients , with a significant overactivation in the supplementary motor area and the ipsi - and contralateral primary motor areas .
### Output Text:
The dyskinetic parkinsonian patients exhibited a pattern of response which was markedly different from those of the normal subjects and non - dyskinetic parkinsonian patients , with a significant overactivation in the supplementary motor area and the ipsi - and contralateral primary motor areas . 