后退的

Methods Sixty human teeth with single root were instrumented using step-back technique, then were divided into six groups and treated with different concentrations EDTA paste and NaClO solution.

选择60颗离体单根管牙，用逐步后退法预备根管，预备后随机分成6组，采用不同质量分数的EDTA糊剂对根管进行处理，分别为5%、10%、15%、17%和20%EDTA糊剂，另设生理盐水组作为对照。

Group 1 was instrumented with SS-K files by step-back technique, group 2 was instrumented with manual Protaper instruments according to manufacturers' directions.

第一组使用不锈钢K锉采用逐步后退法预备近颊根管，第二组使用手用Protaper采用厂家推荐的方法预备近颊根管，第三组使用机用K3采用逐步深入法预备近颊根管。

Methods: One hundred and twenty teeth with curved root canals were randomly divided into 2 groups: 74 curved root canals in group PT were prepared by ProTaper rotary Nickel-Titanium file with crown-down technique, and 75 curved root canals in group SS were prepared by K-files with step-back technique.

选择2005年6月至12月间本院口腔内科行根管治疗的120例患者（120颗牙），随机分为两组：试验组用ProTaper机用镍钛锉及冠根向预备技术预备弯曲根管74个，对照组用不锈钢K型锉及逐步后退法技术预备弯曲根管75个。

METHODS: 8 curved artificial root canals were prepared with stainless steel K files by the step-back technique, the root canals were digitally photographed, the images were analysed by the software Image-Pro Plus, the shapes and positions of the root canals were measured and analysed. SPSS10.0 software package was used for statistical analysis, paired-samples t test was used to compare the difference of the means among sample groups.

使用手用不锈钢K锉，按逐步后退法预备8个弯曲人工根管，根管预备过程中对根管及根尖孔进行微距摄影，用图像分析软件Image-Pro Plus对根管的形态与位置变化进行测量、分析；实验数据采用SPSS10.0统计软件包进行统计学分析，选用配对t检验比较组间差异。

Methods: Fourty-five mandibular second premolars with single oval-shaped root canal were prepared with step-back technique and filled with warm vertical compaction technique. The teeth were divided into three groups randomly: ProTaper group, Mtwo group and manual stainless group. The operating time was recorded.

45颗具有椭圆形根管的下颌前磨牙经逐步后退法预备、热牙胶垂直加压充填后随机分为3组，分别用ProTaper再治疗器械和ProTaper器械，Mtwo再治疗器械和Mtwo器械，手用H锉和K锉去除牙胶。

He comes closer to ask you a puestion, and then shakes your hand.

你向后退，他走的更近来问你问题。

It usually begins with a receding hairline in the late twenties or thirties, but can start earlier.

它通常开始与后退极细，在已故的二十或三十，但可以开始较早。

The first stage is usually a receding hairline, followed by thinning of the hair on the crown and temples.

第一阶段，通常是后退极细，其次是细化的头发，对官方和庙宇。

Although the water are reseeding, weather forecasts predict more heavy rainfall in the next 2 months.

虽然水在后退，但是天气预报预测在之后2个月里有更严重的雨势。

I fall back dazzled at beholding myself all rosy red,/ At having, I myself, caused the sun to rise.- 'Chanticler' by Rostand.

我头晕目眩的后退，为看到我自己全身通红，/为，我自己，升起了太阳——罗斯坦德《雄鸡》。

As she looked at Warrington's manly face, and dark, melancholy eyes, she had settled in her mind that he must have been the victim of an unhappy attachment.

每逢看到沃林顿那刚毅的脸，那乌黑、忧郁的眼睛，她便会相信，他一定作过不幸的爱情的受害者。

Maybe they'll disappear into a pothole.

也许他们将在壶穴里消失