It's - a suture or a stitch has to hold the wound closed so it has to have certain mechanical strength and imagine the problem of making something that's dissolvable so it disappears but also is strong enough to hold a wound closed reliably for a length of time.

能够拉紧切口的缝合线,就必须具有一定的机械张力,大家想像一下制造这种缝合线的难度,身体组织不仅要能吸收这种缝合线,而且这种线必须有足够的张力,一定时间内能够拉紧切口

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If the schools fail to reach required goals set in the charter, which are usually three to five years in length, they can be closed down.

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After the runways were closed for de-icing, the airport extended the length of time between flights for safety reasons, primarily because there was a knock-on effect of flights being delayed at other airports.

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The black matte-jersey, floor-length dress, with a dropped leather waist and notched V neck, that closed the show was the right high note to leave on.

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