With no explanation, label each line with "O", "other-biologything", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart", "building-airport" or "building-hospital" preceded by ":".
By
contrast
,
in
classical
PKU
(
without
dihydrobiopterin
involvement
)
,
prolactin
levels
would
be
relatively
normal
.
By:O
contrast:O
,:O
in:O
classical:O
PKU:other-biologything
(:O
without:O
dihydrobiopterin:other-biologything
involvement:O
):O
,:O
prolactin:other-biologything
levels:O
would:O
be:O
relatively:O
normal:O
.:O