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

• Objective To study the effect of gypenosides on proliferation of neural precursor cells in vitro.
  目的探讨不同浓度绞股蓝皂苷对体外培养的神经前体细胞增殖能力的影响。
• Cyanide can serve as precursor for the amide nitrogen of asparagine.
  氰化物可以作一个天门冬酰胺的酰胺氮前体。
• The effects of orthophosphoric acid concentration in precursor preparation on the catalyst behavior have been studied.
  考察了前驱体制备过程中磷酸含量对催化剂性能的影响。
• Based on studies of precursor events and unusual animal behavior, a warning was issued by local authorities.
  当地政府根据震前先兆与动物的反常行为，发出了地震预警。
• 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。
• 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。
• They alter the way it cleaves amyloid precursor protein.
  它们改变了这个酶切割淀粉样蛋白前体的方式。
• This was a necessary precursor to the development of calculus and a precise quantitative science of physics.
  这是一个必要的前体的发展，微积分和精确的定量科学的物理学。
• Exogenously supplied aspartate is not an active precursor of asparagine in plant tissues.
  外来供给的天门冬氨酸，在植物组织中并不是一个活跃的天门冬酰胺前体。
• Amphetamines is one kind of synthetic compounds whose precursor structure is amphetamine.
  苯丙胺类物质是一大类人工合成的以苯丙胺为母体的化合物。