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then, in 1979, a well-designed study by pediatrician and psychiatrist herbert needleman resolved the dispute by establishing a direct correlation between the lead content of a child's teeth and bad classroom behavior.
到1979年,由儿科医生兼精神病学家赫伯特·内德勒曼(herbert needleman)设计的一个著名实验证明不良的学习成绩与儿童牙齿中的铅含量直接相关,从而为争议下了定论。