Conclusion it is better apical sealing ability in root canals prepared by crown-down technique than step-back technique.

结论短期内冠根向预备技术比逐步后退技术成形的根管更有利于根管充填后根尖孔的密封。

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I pulled his chin down sharp upon the crown of my head, butting him as I had seen the West Indians do, and I felt his flesh tear and the blood gush out, and I yelled, "Apologize!"

我一下把他的下巴拉到我的头顶，像我见过的西印度人那样撞了上去。我感觉他肉撕裂了，血涌了出来，而我大喊道，“道歉！”

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Since the shed roof sloped from 7 feet down to 5 feet, I kept bumping the 6-foot 3-inch high crown of my head on the oak rafters.

单面倾斜的屋顶从7英尺下降到5英尺的时候，我头上6英尺宽3英寸高的帽子不停地撞到橡木椽子。

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So in the years just before 1637, the English court under James I and then later under Charles I -the English crown had been cracking down on the delivery of Puritan sermons in the church.

因此在1637年之前，詹姆斯一世以及,后来的查理一世，领导下的王庭,此时英国的王权已经在极力打击,清教徒训诫仪式的实行。

耶鲁公开课 - 弥尔顿课程节选

The Alex were beaten 5-3 at the Crown Ground, although they were 5-1 down at one stage, with Thordarson describing the defeat as "embarrassing".

BBC: Thordarson embarrassed by defeat

Designers ripped down dated blue-striped wallpaper, then added crown molding and a hand-painted border to the walls.

FORBES: Home Improvement

If you're scoring at home, NVIDIA currently holds the lead in single-GPU graphics cards with its GeForce GTX 580, but ATI's dual-chip Radeon HD 5970 has been holding down the absolute speed crown for a good long while.

ENGADGET: AMD launches Radeon HD 6990 powerhouse for $699, maintains 'world's fastest' title