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: Both DHEA 50 mg / kg ( p < 0 . 05 ) , and 100 mg / kg ( p < 0 . 01 ) significantly decreased all movements compared with the amphetamine - induced locomotion group .
### Output Text:
Both <span class="chemical">DHEA</span> 50 mg / kg ( p < 0 . 05 ) , and 100 mg / kg ( p < 0 . 01 ) significantly decreased all movements compared with the <span class="chemical">amphetamine</span> - induced locomotion group . 