3495
The occurrence of PVC ' s correlated significantly with the fall in serum K + observed r = 0 . 72 , p less than 0 . 001 .
 Chemical: K
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Disease, Chemical 
Text: {0} 
Answer:
 Chemical: K