在一九五七年中，这些民族等于四十四百万人。

In 1957 these nationalities equalled more than 44 million people.

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One thing that happened was that after 1956, 1957 the number of cases were down, there was a small bump here, the cases were up.

一九五六年后发生了一件事,在一九五七年,病例的数量有所下降,但在这里却有一个很小的上扬,病例数量上升了

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