授予加州千橡市的一名医生——唐纳德·昂格尔（Donald Unger），60年来的每一天，他把左手指节掰得咯吱作响，但从不掰右手指节，研究这样做是否会引起关节炎。

To Donald Unger, a doctor in Thousand Oaks, California, who cracked the knuckles of his left hand, but never those on his right, every day for 60 years to investigate whether it caused arthritis.

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