It's the time in which but it's the time in which long distance commerce began to take hold, because of transportation revolutions: canals, roads, railroads in particular.

它是一个时期,这是一个远距离商业开始产生影响的时代,主要原因便是运输方式的革新,运河,公路,特别是铁路

耶鲁公开课 - 美国内战与重建课程节选

These released particles can now go on and infect neighboring cells, they can travel in the bloodstream to infect cells at a distance and the virus spreads throughout a multicellular host.

这些释放出的病毒颗粒,可以继续感染邻近的细胞,它们可以随着血流去感染远距离的细胞,于是病毒可以在多细胞宿主体内全面扩散

耶鲁公开课 - 生物医学工程探索课程节选