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LESLIE L. IVERSEN The present series of volumes is well timed, as the impact of molecular genetics on pharmacology has been profound, and a comprehensive review of the rapid advances of the past decade is much needed. Since the pioneering work of Dale, Ariens, and others in the early years of this century, much of pharmacology has been founded on the concept of receptors. To begin with, the receptor was conceived of as a "black box," which recognized and transduced the biological effects of neurotransmit- ters, hormones, or other biological messengers-and which could also represent a target...