490
RESULTS : Both timolol solution and timolol gellan reduced the mean 24 - hour heart rate compared with placebo ( P < or = . 001 ) , and this reduction was most pronounced during the daytime ( - 7 . 5 % change in mean heart rate , - 5 . 7 beats / min ) .
 Chemical: timolol; Chemical: timolol
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: timolol; Chemical: timolol