Quarks, which we also cannot see, are a model to explain the properties of the protons and neutrons in the nucleus of an atom.

夸克同样看不到，但它却是解释原子核中质子、中子性质的理论模型。

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Objective To investigate the effects of steady shear flow on the deformation properties of an adherent leukocyte and its nucleus.

目的研究稳定剪切流动对黏附于血管表面的白细胞及其细胞核变形的影响。

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