blood was collected from the utero-ovarian vein of guinea-pigs on days 3 , 9 , 10 , 11 , 12 , 13 , 14 and 15 of the oestrous cycle , and from animals injected with oestrogen over days 4-6 and used on day 7 .
C0042149
utero
C0025329
oestrous cycle