10613
Objective : The purpose of the present study was to evaluate the effects of melatonin on biochemical and cardiovascular changes resulting from exposure to 2 , 3 , 7 , 8 - tetrachlorodibenzo - p - dioxin ( TCDD ) , a polychlorinated dibenzo - para - dioxin . Methods : A total of 24 Sprague - Dawley rats were divided equally into the following four groups : ( 1 ) control group was administered with 0 . 5 mL corn oil by gavage and 0 . 5 cc vehicle of melatonin ( proportionally nine parts physiological serum + one part ethyl alcohol ) intraperitoneally for 4 weeks , ( 2 ) the melatonin group was given 5 mg / kg / day melatonin intraperitoneally for 4 weeks , ( 3 ) the TCDD group was given 500 ng / kg / day TCDD by gavage for 4 weeks and ( 4 ) the TCDD + melatonin group was given TCDD ( 500 ng / kg / day ) by gavage and melatonin ( 5 mg / kg / day ) intraperitoneally simultaneously for 4 weeks .
 Chemical: melatonin; Chemical: 2 , 3 , 7 , 8 - tetrachlorodibenzo - p - dioxin; Chemical: TCDD; Chemical: polychlorinated dibenzo - para - dioxin; Chemical: melatonin; Chemical: ethyl alcohol; Chemical: melatonin; Chemical: melatonin; Chemical: TCDD; Chemical: TCDD; Chemical: TCDD; Chemical: melatonin; Chemical: TCDD; Chemical: melatonin
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
 Chemical: melatonin; Chemical: 2 , 3 , 7 , 8 - tetrachlorodibenzo - p - dioxin; Chemical: TCDD; Chemical: polychlorinated dibenzo - para - dioxin; Chemical: melatonin; Chemical: ethyl alcohol; Chemical: melatonin; Chemical: melatonin; Chemical: TCDD; Chemical: TCDD; Chemical: TCDD; Chemical: melatonin; Chemical: TCDD; Chemical: melatonin