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 : Nine of 30 patients receiving lidocaine experienced TNSs , 1 of 30 patients receiving prilocaine ( P = 0 . 03 ) had them , and none of 30 patients receiving bupivacaine had TNSs .
### Output Text:
RESULTS : Nine of 30 patients receiving <span class="chemical">lidocaine</span> experienced TNSs , 1 of 30 patients receiving <span class="chemical">prilocaine</span> ( P = 0 . 03 ) had them , and none of 30 patients receiving <span class="chemical">bupivacaine</span> had TNSs . 