Definition: Given an abstract, generate a keyword (a noun phrase) that best describes the focus or contribution of the paper. Such keywords can be directly from the given abstract or outside it.
Input: Abstract: Intraoral patch testing was performed in 3 subjects, 2 of whom were contact sensitive to nickel. Maxillary acrylic plates carrying test pieces containing 66% nickel were applied for 48 h, and readings were performed 24 h after removal. Few if any clinical signs were detected, but biopsies from the mucosal contact sites showed lichenoid reactions. Biopsies from control sites showed no or slight non-specific inflammatory reactions.

Adult