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: The appearance of nephrotic syndromes such as proteinuria , hypoalbuminemia , hypercholesterolemia and increase in blood nitrogen urea , induced in rats by injection of puromycin aminonucleoside was markedly inhibited by oral administration of Dup 753 ( losartan ) , a novel angiotensin II receptor antagonist , at a dose of 1 or 2 mg / kg per day .
### Output Text:
The appearance of nephrotic syndromes such as proteinuria , hypoalbuminemia , hypercholesterolemia and increase in <span class="chemical">blood nitrogen urea</span> , induced in rats by injection of <span class="chemical">puromycin aminonucleoside</span> was markedly inhibited by oral administration of <span class="chemical">Dup 753</span> ( <span class="chemical">losartan</span> ) , a novel <span class="chemical">angiotensin II</span> receptor antagonist , at a dose of 1 or 2 mg / kg per day . 