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: Our results indicated that 1 ) treatment of mice with ADR caused cardiovascular arrhythmias characterized by bradycardia , extension of ventricular depolarization time ( tQRS ) , and failure of QRS at high concentrations ( 10 - 14 mg / kg body weight cumulative dose ) ; 2 ) the heart mitochondria underwent swelling , fusion , dissolution , and / or disruption of mitochondrial cristae after several weeks of treatment .
### Output Text:
Our results indicated that 1 ) treatment of mice with <span class="chemical">ADR</span> caused cardiovascular arrhythmias characterized by bradycardia , extension of ventricular depolarization time ( tQRS ) , and failure of QRS at high concentrations ( 10 - 14 mg / kg body weight cumulative dose ) ; 2 ) the heart mitochondria underwent swelling , fusion , dissolution , and / or disruption of mitochondrial cristae after several weeks of treatment . 