nucleus

the central structure of the lens that is surrounded by the cortex

被皮质包围的晶状体中央结构

lens nucleus

a part of the cell containing DNA and RNA and responsible for growth and reproduction

细胞的一部分，含有DNA和RNA，负责生长和繁殖

cell nucleus

karyon

any histologically identifiable mass of neural cell bodies in the brain or spinal cord

脑或脊髓中任何组织学上可识别的神经细胞体

a small group of indispensable persons or things

一小群不可缺少的人或事物

five periodicals make up the core of their publishing program

五种期刊构成了他们出版计划的核心

core

core group

the positively charged dense center of an atom

原子带正电的稠密中心

(astronomy) the center of the head of a comet

（天文学）彗星头部的中心

consists of small solid particles of ice and frozen gas that vaporizes on approaching the sun to form the coma and tail

由冰和冰冻气体组成的小固体颗粒，在接近太阳时蒸发形成彗发和尾巴