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英语达人来吧,帮忙翻译一小段

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英语达人来吧,帮忙翻译一小段
The amount of iron in the body depends on age, gender, nutrition, and general state of health. There are limited iron stores in the newborn and these gradually increase with age until adulthood. In the healthy human male adult, there is between 35 and 45 mg iron per kg body mass.16 Two-thirds of total body iron is incorporated into hemoglobin by erythroid cells, while the remaining third is stored in the liver or as myoglobin in muscle or is found in reticuloendothelial macrophages.16 Only a small fraction circulates in the plasma bound to transferrin or is present in the cellular labile iron pool.20 Iron levels in women are generally lower due to smaller muscle and liver mass and iron loss through menstruation. Depletion of iron stores may take several years and can occur because of pregnancy, malnutrition, or malabsorption of dietary iron as well as in clinical conditions that cause hemorrhage. As there is a limited capacity for humans to excrete iron, the amount of dietary iron absorbed is tightly regulated. Approximately 1 to 2 mg of iron enters and leaves the body each day.
身体中铁的含量取决于年龄、性别、营养,和总的健康状态.新生儿体内铁含量有限,但在成年的过程中会不断增长.健康的成年男性,每千克体重含铁量在35至45毫克之间.人体内三分之二的铁是由红细胞带入血红蛋白的,其余的三分之一则储存在肝脏中或肌肉的肌红蛋白中或是网状内皮组织的巨噬细胞中.只有极少数的铁是在铁传递蛋白的血浆中循环,或是以细胞不稳定铁源形式出现.女性体内含铁量普遍较低,这是因为她们的肌肉较少和肝脏较小以及月经失血.铁量的损耗可能会历经数年,并可能由怀孕,营养失调或食物铁吸收障碍和医疗过程失血引起.因为人类排泄铁的能力有限,饮食中铁的吸收是非常有规律的.大约每天有1至2毫克的铁进出人体.