tokens: METHODS : ASA was administered as a single dose on GD 9 ( 0 , 250 , 500 , or 625 mg / kg ) , 10 ( 0 , 500 , 625 , or 750 mg / kg ) , or 11 ( 0 , 500 , 750 , or 1000 mg / kg ) and from GD 6 to GD 17 ( 0 , 50 , 125 , or 250 mg / kg a day ) in the multiple dose study to SD rats .