A warm drink of milk before bed has long been the best choice for those wanting a good night's sleep. But now a study has found it really does help people nod off（打瞌睡）—if it is milked from a cow at night.

    Researchers have discovered that “night milk” contains more melatonin(褪黑激素), which has been proven to help people feel sleepy and reduce anxiety（焦虑）.The study, by researchers from Seoul, South Korea, involved mice being fed with dried milk powder（奶粉） made from cows milked both during the day and at night. Those given night milk, which contained 10 times the amount of melatonin, were less active and less anxious than those fed with the milk collected during daytime, according to the study published in The Journal of Medicinal Food.

    Night milk quickened the start of sleep and caused the mice to sleep longer.

    While the effect of cow milk harvested at different time has not been tested on humans up to now, taking melatonin drugs has been suggested to those who have trouble falling asleep at night.

    Previous （以前的）studies have also showed that milk can be excellent for helping sleep because of the calcium content, which helps people to relax.

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虎门销烟

    1839年6月3日，是中国历史上值得纪念的日子。

    这一天，天气晴朗，碧海、蓝天、绿树，把古老的虎门寨装点得分外壮丽。一大早从各地闻讯赶来的男男女女、老老少少，把宽阔的海滩挤得水泄不通。新搭起的礼台上彩旗林立；礼台下，一侧是身着朝服的文武官员，另一侧是应邀前来观看的外国商人。

    午后二时许，林则徐等人健步登上礼台。这时候，礼炮轰鸣，群情沸腾。随着林则徐一声令下，震惊中外的虎门销烟开始了。只见一群群光着脊梁、赤着双脚的民工，先向灌了水的销烟池里撒下盐巴，再把收缴来的鸦片抛入池内，然后又把一担担生石灰倒下去。顿时，销烟池里像开了锅一样，“咕嘟咕嘟”直冒泡，散发出股股难闻的气味。

    看到害人的鸦片被销毁了，成千上万的老百姓激动得跳哇，叫哇，欢呼声响彻虎门上空。

    销烟整整持续了23天，二百多万斤鸦片化为烟渣，随着潮水卷进了咆哮的大海之中。

    虎门销烟这一伟大壮举，沉重地打击了外国侵略者的嚣张气焰，它向全世界表明，中国人民是不可欺侮的！