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科学美国人60秒 SSS 美白牙贴会改变牙齿中的蛋白质

时间：2020-01-09 05:59:27

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（单词翻译）

 

This is Scientific American's 60-second Science, I'm Christopher Intagliata.

Of all the stuff you can buy on eBay — here's a new one: human teeth. "I think I probably averaged maybe $5 a tooth." Kelly Keenan, a biochemist at Stockton University in New Jersey1. Keenan chased down the chompers to investigate what whitening strips do to a tooth's chemical composition. So she stuck the teeth in styrofoam, applied2 the whitening strips per manufacturer instructions, and added some artificial saliva3: a liquid mixture at the pH and with salts you'd find in regular spit.

Treatments complete, she extracted proteins from the teeth. And found that the more rounds of whitening the teeth experienced, the fewer proteins she could recover — because hydrogen peroxide in the whitening strips was snipping4 chemical bonds. "The bigger picture is that hydrogen peroxide can penetrate5 the enamel6 and dentin and it can cause your proteins to break down. And smaller pieces are removed from those proteins."

She and her undergraduate students presented on that research at the 2019 Experimental Biology meeting in Orlando. Now this is just a preliminary study. And the pulp7 of your teeth can replenish8 proteins in the dentin, though not the enamel — so it's unclear whether these effects would cause permanent damage in real, living teeth. One thing's for sure: supplies of teeth for experiments seem to be plentiful9.

I think I bought a set of 15. And the person's like, let me know if you need more. This person also claimed the teeth were from his mouth, which, you don't have that many more to go!

Thanks for listening for Scientific American — 60-Second Science. I'm Christopher Intagliata.


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1 jersey Lp5zzo     
n.运动衫
参考例句：
  • He wears a cotton jersey when he plays football.他穿运动衫踢足球。
  • They were dressed alike in blue jersey and knickers.他们穿着一致，都是蓝色的运动衫和灯笼短裤。
2 applied Tz2zXA     
adj.应用的；v.应用，适用
参考例句：
  • She plans to take a course in applied linguistics.她打算学习应用语言学课程。
  • This cream is best applied to the face at night.这种乳霜最好晚上擦脸用。
3 saliva 6Cdz0     
n.唾液，口水
参考例句：
  • He wiped a dribble of saliva from his chin.他擦掉了下巴上的几滴口水。
  • Saliva dribbled from the baby's mouth.唾液从婴儿的嘴里流了出来。
4 snipping 5fe0030e9f7f57e9e018d33196ee84b6     
n.碎片v.剪( snip的现在分词 )
参考例句：
  • The crew had been snipping it for souvenirs. 舰上人员把它剪下来当作纪念品。 来自辞典例句
  • The gardener is snipping off the dead leaves in the garden. 花匠在花园时剪枯叶。 来自互联网
5 penetrate juSyv     
v.透(渗)入；刺入，刺穿；洞察，了解
参考例句：
  • Western ideas penetrate slowly through the East.西方观念逐渐传入东方。
  • The sunshine could not penetrate where the trees were thickest.阳光不能透入树木最浓密的地方。
6 enamel jZ4zF     
n.珐琅，搪瓷，瓷釉；(牙齿的)珐琅质
参考例句：
  • I chipped the enamel on my front tooth when I fell over.我跌倒时门牙的珐琅质碰碎了。
  • He collected coloured enamel bowls from Yugoslavia.他藏有来自南斯拉夫的彩色搪瓷碗。
7 pulp Qt4y9     
n.果肉，纸浆；v.化成纸浆，除去...果肉，制成纸浆
参考例句：
  • The pulp of this watermelon is too spongy.这西瓜瓤儿太肉了。
  • The company manufactures pulp and paper products.这个公司制造纸浆和纸产品。
8 replenish kCAyV     
vt.补充；(把…)装满；(再)填满
参考例句：
  • I always replenish my food supply before it is depleted.我总是在我的食物吃完之前加以补充。
  • We have to import an extra 4 million tons of wheat to replenish our reserves.我们不得不额外进口四百万吨小麦以补充我们的储备。
9 plentiful r2izH     
adj.富裕的，丰富的
参考例句：
  • Their family has a plentiful harvest this year.他们家今年又丰收了。
  • Rainfall is plentiful in the area.这个地区雨量充足。

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