第四节营养性巨幼红细胞性贫血营养性巨幼红细胞性贫血（nutritionalmegaloblasticanemia）又称大细胞性贫血，主要由叶酸或（和）维生素B12</sub>直接或间接缺乏所致，大多因摄入不足而导致直接缺乏引起。
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