Bulls and bears are used to symbolize conditions on Wall Street.

多头和空头被用来象征华尔街的状况。

Two steroid hormones—testosterone and cortisol—come out in force during the excesses of bull and bear markets.

强劲的牛市和熊市出现时, 　两类固醇激素，就是睾酮和皮质醇会剧增。