tokens: The cells were exposed to UV light delivered by a bank of 6 Philips TL20/12RS sun lamps emitting primarily in the UVB range in the absence and presence of tryptophan .
folded_tokens: the cells were exposed to uv light delivered by a bank of 6 philips tl20/12rs sun lamps emitting primarily in the uvb range in the absence and presence of tryptophan .
labels: O O O O O B-other_name O O O O O O O B-other_name I-other_name I-other_name I-other_name O O O O B-other_name I-other_name O O O O O O B-amino_acid_monomer O