The symptoms were mostly caused by certain diseases or complications of factors, clinical manifestations were vomiting blood, black stool or no obvious symptoms.

本病临床上多为某些疾病或因素引起的并发症，临床主要表现为呕血，黑便或无明显症状。

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Our family purchased the infamous black stool because my brother told my parents that he must have an electric piano. And he needed something to sit on while he played.

我们家买下这个声名狼籍的的黑凳子是因为我哥哥跟我父母说他必须拥有一台电钢琴，并且他弹钢琴时需要坐的东西。

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Addressing a large group of mainly private shareholders at the meeting, Mr Cook -- sitting on a high stool, and dressed in a black shirt and jeans -- defended Apple's growth rate and recent performance.

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