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: Intramuscular hepatitis B immune globulin combined with lamivudine in prevention of hepatitis B recurrence after liver transplantation .
### Output Text:
Intramuscular hepatitis B immune globulin combined with <span class="chemical">lamivudine</span> in prevention of hepatitis B recurrence after liver transplantation . 