克隆排除了繁殖这种全靠碰运气的事儿的偶然因素.

Cloning removes the chance element from the lottery of reproduction.

这些特殊的偶然因素因病人的不同而各有区别.

These particular causal factors vary from patient to patient.

最为重要的是观察性研究无法区分风险指标和偶然因素.

Most importantly, observational studies cannot distinguish indicators of risk from causal factors.

偶然因素可以决定歌曲排列榜首，其作用决不亚于歌曲质量的好坏。

Accidents determine the song at the top of the chart as much as true quality.

最好的事物中总是存在着某种偶然因素，不管是思想、言论还是行动。

There is always some accident in the best of things, whether thoughts or expression or deeds.