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: Safety and efficacy of fluocinolone acetonide intravitreal implant ( 0 . 59 mg ) in birdshot retinochoroidopathy .
### Output Text:
Safety and efficacy of <span class="chemical">fluocinolone acetonide</span> intravitreal implant ( 0 . 59 mg ) in birdshot retinochoroidopathy . 