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: Results showed that SSR103800 ( 10 - 30 mg / kg p . o . ) blocked hyperactivity induced by the non - competitive NMDA receptor antagonist , MK - 801 and partially reversed spontaneous hyperactivity of NMDA Nr1 ( neo - / - ) mice .
### Output Text:
Results showed that <span class="chemical">SSR103800</span> ( 10 - 30 mg / kg p . o . ) blocked hyperactivity induced by the non - competitive <span class="chemical">NMDA</span> receptor antagonist , <span class="chemical">MK - 801</span> and partially reversed spontaneous hyperactivity of <span class="chemical">NMDA</span> Nr1 ( neo - / - ) mice . 