1.如播卡顿或失败可切换片源。
2.如播放失败可点击切换线路。
3.我们最近发现视频里开始有插播广告，每个视频大概有好几秒，可以用快进跳过。这些广告都是视频源那边自带的，我们这边无法控制，谢谢大家的谅解。
年份：
2014
主演：
类别：
Changes to the bacteria that live inside all of us are responsible for increasing the number of people with allergies, suggests new research.
In this episode of Horizon, the show investigates this claim by conducting a unique experiment with two allergic families in order to find out just what it is in the modern world that is to blame. With a raft of mini cameras, GPS units an...
