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時差N小時:恐龍也會得癌癥?

所屬教程:時差N小時

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2016年04月04日

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https://online2.tingclass.net/lesson/shi0529/0009/9697/348.mp3
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If you think that cancer is only found in humans, orthat it's a modern disease, think again. Scientistshave not only found cancer in many other animals,they have found it in dinosaurs that lived more than65 million years ago. Wondering if fossils could tellus something about ancient cancer, scientiststraveling with a portable x-ray machine scanned ten-thousand dinosaur vertebrae of over 700 museumspecimens.

如果你認為癌癥只會出現(xiàn)在人類身上,或者它只是一種現(xiàn)代疾病,那么你需要從新審視一下這個問題了。科學家不僅發(fā)現(xiàn)其它很多動物患有癌癥,而且還發(fā)現(xiàn)生活在距今6500萬年前的恐龍也有癌癥。考慮到能夠通過化石來了解古代癌癥,科學家用便攜式X光儀對700個博物館標本近1萬件恐龍脊椎骨進行了掃描。

These included many popular dinosaurs such as Stegosaurus, Triceratops and Tyrannosaurus.Much to their surprise, they found that only one group suffered from cancer-the hadrosaurs, or“duck-billed” dinosaurs. 29 benign tumors were found in the tail bones of 97 animals. Thesewere mostly hemangiomas or tumors of the blood vessels.

經(jīng)過掃描的恐龍化石包括許多我們比較熟悉的恐龍,比如劍龍,三角恐龍和暴龍。另科學家十分驚奇的是,僅有一組恐龍是癌癥的受害者——它就是鴨嘴龍。研究人員在97個恐龍的尾骨里發(fā)現(xiàn)了29個良性腫瘤塊。它們大多是血管瘤或是脈管瘤。

Doctors find the same type of tumors in humans today. One Edmontosaurus also had amalignant tumor. Why did duck-Billed dinosaurs have cancer and not the others? Scientistsaren't sure. They thought that if hadrosaurs were long-lived, they would have a greater chanceof developing cancer, but they lived relatively short lives. These twenty-five foot long herbivoresneeded plenty to eat, so diet was another thing scientists considered.

醫(yī)生們在今天的人類身上也發(fā)現(xiàn)了這類腫瘤。在一個愛德蒙托龍身上還發(fā)現(xiàn)了惡性腫瘤。為什么鴨嘴龍會患上癌癥,而不是其它的恐龍呢?這一點科學家也不得而知。科學家認為,如果鴨嘴龍存活的時間很長,那么它們患癌癥的幾率會很大,但它們存活的時間相對較短。這些25英尺長的草食動物需要吃很多東西,因此科學家把它們的飲食作為另一個考慮因素。

Maybe conifers were to blame. Hadrosaurs ate plenty of them and they did contain knowncarcinogens. The trouble is, other conifer eaters didn't exhibit the same cancer. The cause ofhadrosaur cancer remains a mystery today, but dinosaur fossils are helping unlock secrets ofdiseases millions of years old. Who knows what else they'll reveal.

也許罪魁禍首是針葉樹。鴨嘴龍要吃很多針葉樹葉,這些針葉樹確實含有已知的致癌物。但問題是,其它吃針葉樹的恐龍并沒有患同樣的癌癥。鴨嘴龍的癌癥病因至今還是個謎,但恐龍化石幫助我們揭開了隱藏了百萬年之久的秘密. 誰知道它們還會揭示什么呢?

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