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: Forty - four percent of patients with uveitis had one or more identifiable signs or symptoms , such as red eye , ocular pain , decreased visual acuity , or photophobia , in order of decreasing frequency .
### Output Text:
Forty - four percent of patients with uveitis had one or more identifiable signs or symptoms , such as red eye , ocular pain , decreased visual acuity , or photophobia , in order of decreasing frequency . 