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allergy – n. a medical condition that causes someone to become sick after eating, touching, or breathing something that is harmless to most people : allergic – adj.
mechanism – n. a process or system that is used to produce a particular result < Scientists are studying the body's mechanisms for controlling weight. >
pediatrician – n. a doctor who treats babies and children
refrain – v. to keep from giving in to a desire or impulse
challenge – v. to administer a physiological and especially an immunologic challenge to (an organism or cell)
eczema – n. an inflammatory condition of the skin characterized by redness, itching, and oozing vesicular lesions which become scaly, crusted, or hardened
