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: However , OD was significantly higher in all patients with thrombosis ( n = 48 , 1 . 34 + / - 0 . 89 ) , including isolated - HIT patients who later developed thrombosis within 30 d ( n = 8 , 1 . 84 + / - 0 . 64 ) as compared to isolated - HIT patients who did not develop thrombosis ( 0 . 96 + / - 0 . 75 ; P = 0 . 011 and P = 0 . 008 ) .
### Output Text:
However , OD was significantly higher in all patients with thrombosis ( n = 48 , 1 . 34 + / - 0 . 89 ) , including isolated - HIT patients who later developed thrombosis within 30 d ( n = 8 , 1 . 84 + / - 0 . 64 ) as compared to isolated - HIT patients who did not develop thrombosis ( 0 . 96 + / - 0 . 75 ; P = 0 . 011 and P = 0 . 008 ) . 