They found that plenty of kids changed weight categories as they grew, with some bulking up and others thinning out.

他们发现很多的小孩当他们发育的时候改变了重量级别，有些人是变胖，有些人是变瘦。

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If weight bearing or stress loading of the affected joint continues, thinning of the cartilage may progress to eventual full-thickness cartilage loss.

如果受损的关节持续负重或承受应力，软骨变薄可进行下去，直到最后全层软骨消失。

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These drugs may have serious side effects, including weight gain, thinning of the skin and bones, and decreased defense against infection.

这些药有严重副作用，包括体重增加，皮肤骨质变薄，抗感染力下降。

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Also, losing weight quickly could lead to gallstones and thinning hair because dieters are getting the minimum amount of nutrition, which can affect hair and bone density.

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