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: In contrast to nifedipine , CD - 832 ( 10 micrograms / kg / min ) prevented the decrease in percentage segmental shortening from 32 + / - 12 % to 115 + / - 26 % of the control value ( P < . 01 ) and ST - segment elevation from 5 . 6 + / - 1 . 0 mV to 1 . 6 + / - 1 . 3 mV ( P < . 01 ) at 3 min after ISO infusion with stenosis .
### Output Text:
In contrast to <span class="chemical">nifedipine</span> , <span class="chemical">CD - 832</span> ( 10 micrograms / kg / min ) prevented the decrease in percentage segmental shortening from 32 + / - 12 % to 115 + / - 26 % of the control value ( P < . 01 ) and ST - segment elevation from 5 . 6 + / - 1 . 0 mV to 1 . 6 + / - 1 . 3 mV ( P < . 01 ) at 3 min after <span class="chemical">ISO</span> infusion with stenosis . 