Traces of the chemical are often found in mouse and human urine, leading scientists to wonder whether the drug is being made naturally or being delivered by something the subjects consumed.

在老鼠和人的尿中经常可发现这种化学品的痕迹，科学家们不知道这药物是自然产生的还是从实验对象使用的某种东西中带来的。

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Another theory traces the theater's origin from the human interest in storytelling.

另一个追溯戏剧起源的理论认为它来自人们对叙述故事的兴趣。

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Most early treatment is hemangioma, another can shorten the time of treatment for the damage to human skin, especially the damage may be less after recovery, basically leave no traces.

血管瘤最早期治疗一个是可以缩短治疗时间，另外对于人体造成的伤害尤其是对皮肤造成的伤害可能会少，痊愈后基本上不留任何痕迹。

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Nothing better shows our heavenly origins, our divine seed, our human intellect, those holy traces of Promethean fire."

没有什么能更好的讲述我们的起源，我们的子孙，我们人类的智力，生命之火神圣的踪迹“

耶鲁公开课 - 弥尔顿课程节选

Underwater cultural heritage refers to all traces of human existence having a cultural, historical or archaeological character, which have been partially or totally under water, periodically or continuously, for at least 100 years.

UNESCO: MEDIA SERVICES

How unusual Dr Marlar discovered when he applied his biochemical assay to the coprolite and found traces of human myoglobin, which were not detected in prehistoric coprolites from other sites or in modern faecal samples.

ECONOMIST: Anthropophagy

"Those episodes proved to be the single most important stimulus for the major transformations in human history, " said Weiss, who digs through the traces of vanished empires for evidence of these climatic events.

CNN: Past may hold clues to climate's future