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: We succeeded in reproducing an eczematous lesion on the apparently normal skin of a patient with atopic dermatitis by scratching and continuous application of an ointment containing ferritin-labelled mite antigen. Percutaneous entry of mite antigen was demonstrated in skin biopsies by Fe-staining. Scratched skin first showed an urticarial reaction typical of type I allergy which later changed into an eczematous reaction typical of type IV allergy. This change was also shown histologically.

Skin Tests.