Chemistry that deals with mInute quantities of materials,frequently less than one milligram In mass or one milliliter In volume. 微量化学研究极小数量物质的化学，通常研究对象质量小于一毫克或体积小于一毫升
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Zemel says that when calcium levels are low, the body releases a hormone that helps squeeze the most out of every available milligram of the mineral 泽莫尔博士说，当人体中的钙含量偏低时，身体里就会产生一种荷尔蒙，它能帮助肌体最大限度地吸收所摄入的钙。
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