in the blood

基本解释

Curly hair runs in the blood.
卷发在这家是世代相传的。
《新英汉大辞典》
The vitamins were chosen because they control the amounts of an amino acid called homocysteine in the blood.
选用维生素是因为他们控制了血液中一种叫高半胱氨酸的氨基酸的含量。
High levels of homocysteine (an amino acid) in the blood have been linked to increased risk of premature coronary heart disease and stroke, even among people who have normal cholesterol levels.
血液中的高同型半胱氨酸（氨基酸）会导致早发冠心病和中风，这一现象甚至发生在拥有正常胆固醇指标的人群身上。

Over the years,researchers have identified several substances in the blood that can serve as what they call cardiac biomarkers.
Humoral refers to immunity in the blood and it's immunity that's in the blood in the form of antibodies.
体液免疫代表着血液中的免疫机制,血液中的免疫机制是以抗体的形式存在的
耶鲁公开课 - 生物医学工程探索课程节选
For the life of the flesh is in the blood, and I have assigned it to you for making expiation for your lives upon the altar."
因为活物的生命是在血中，我把这血赐给你们，可以在坛上,为你们的生命赎罪“
耶鲁公开课 - 旧约导论课程节选

Brain blood vessels have a membrane structure insulating them from chemicals circulating in the blood.
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