| 摘要 |
<p>Spermatozoa are immobilised by cooling and introduced into a nutritive fractionating media. The fractionating media has a density gradient so that when the sperms are introduced into the middle of the column the denser X-chromosome contg. sperms descend and the less dense Y-chromosome contg. sperms rise. The fractionation is carried out under reduced pressure at -5 degrees to +2 degrees C and a pH of 6-8 in a media having a S.G. of 1.01-1.15 g./cm3 at 0 degree C. The appts. for the fractionation is claimed. The process allows one to choose the sex of the progeny of mammals for economic and social reasons.</p> |
