precursor

英 [priˈkɜːsə(r)]

美 [priˈkɜːrsər]

n.  先驱; 先锋; 前身

复数：precursors　

TOEFLGRE化学

Collins.1 / BNC.10361 / COCA.9664

牛津词典

noun

• 先驱；先锋；前身
  a person or thing that comes before sb/sth similar and that leads to or influences its development

柯林斯词典

• N-COUNT 先驱；先锋；前身
  Aprecursorof something is a similar thing that happened or existed before it, often something which led to the existence or development of that thing.
  1. Real tennis, an ancient precursor of the modern game, originated in the eleventh century...
     室内网球，现代网球运动的古老前身，起源于11世纪。
  2. He said that the deal should not be seen as a precursor to a merger.
     他说该笔交易不应该被看作是合并的前兆。

英英释义

noun

• something that precedes and indicates the approach of something or someone
  Synonym:harbingerforerunnerpredecessorherald
• a person who goes before or announces the coming of another
  Synonym:forerunner
• a substance from which another substance is formed (especially by a metabolic reaction)

双语例句

• Cyanide can serve as precursor for the amide nitrogen of asparagine.
  ***可以作一个天门冬酰胺的酰胺氮前体。
• It is a precursor of many aromatic compounds and of alkaloids such as curare and morphine.
  苯丙氨酸是苯化合物以及像箭毒和***等生物碱的前体。
• Amphetamines is one kind of synthetic compounds whose precursor structure is amphetamine.
  ***类物质是一大类人工合成的以***为母体的化合物。
• Calcium deposits in the coronary arteries are considered a precursor of future heart disease.
  冠状动脉中的钙沉积是导致人们将来患上心脏病的先兆症状。
• Comparing the ratio of testosterone to epitestosterone can then indicate whether testosterone or a precursor has been taken.
  因此测定睾酮与表睾酮的比例，能够反映出（运动员）是否服用了睾酮或者它的前体药物。
• They then examined their arteries for arterial stiffness, often a precursor to high blood pressure and heart disease.
  然后研究者检查了被测试着的动脉硬化情况。动脉硬化是高血压和心脏疾病的前兆。
• This is because the active drug ingredient is not dopamine itself but various precursor molecules.
  这是因为活性治疗药物成分不是多巴胺本身，而是一些前体药物。
• But whether scientific cooperation can become a precursor for political collaboration is less evident.
  但是科学合作是否能成为政治合作的一个先兆，这并不明显。
• In plant cells the principal precursor of alanine, as well as leucine and valine, is pyruvate.
  植树细胞中丙氨酸和亮氨酸、缬氨酸的主要前体是丙酮酸。
• Papain-catalyzed synthesis of aspartame precursor z-apm in biphasic solvent system wasinvestigated.
  本文报道在两相溶剂体系中利用木瓜蛋白酶催化合成aspartame前体z－apm的研究。