{HEAD ~ Identification} of {TAIL ~ metabolite peaks} was based on mass accuracy and isomeric species were assigned based on diagnostic fragment ions present during tandem mass spectrometry for many of the identified metabolite peaks 
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{ HEAD ~ Identification } of { TAIL ~ metabolite peaks } was based on mass accuracy and isomeric species were assigned based on diagnostic fragment ions present during tandem mass spectrometry for many of the identified metabolite peaks
HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH