good news for 1 lovers: scientists appear to be one step closer to being able to 2 teeth in humans. a study in developmental biology explains how sharks and other 3 life are able to regrow teeth continuously throughout their lives.
告诉碳酸饮料爱好者一个好消息：科学家向人类牙齿再生技术又迈进了一步。《发育生物学》上刊登了一项研究，向我们解释了鲨鱼及其它海洋生物可以终生不断再生牙齿的原理。
until now, that process had been "poorly understood and [remained] virtually uncharacterized from a developmental
4 standpoint." researchers at the university of sheffield studying the
5 of catsharks discovered a "special set of epithelial cells" called dental lamina that are responsible for
6 teeth, according to a press release.
those
7 goes back 450 million years and are likely responsible for producing the first teeth in vertebrates, as well as generating all the teeth since, including those in humans. in fact, humans have the same dental lamina, but they produce teeth only twice ("baby" teeth, then the adult versions) before the cells disappear. researchers believe it's possible for this research to eventually help people who've lost teeth.
"the
8 films taught us that it's not always safe to go into the water, but this study shows that perhaps we need to in order to develop therapies that might help humans with tooth loss," says researcher dr. gareth fraser.
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