通常身体能在24小时内替换收集的体积，捐献者可以一周捐献两次，尽管这个原则在每个国家不同。

The body will typically replace the collected volume within 24 hours, and donors typically donate up to twice a week, though this varies by country.

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另一个解释是，提供的利润在美国市场允许公司以支付转换收集到的意见的基础研究到可行的商业药品。

Another explanation is that the profits available in U. s. markets allow companies to cover the costs of converting the ideas gleaned from basic research into workable commercial medicines.

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