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VTK is an object-oriented universal class library, which is widely used in science and engineering field. In this paper, the visualization pipeline of VTK is introduced, and it is discuss that principles and implemental methods of two interactive cutting. This technique could be applied to medical teaching, scientific research and clinical diagnosis where virtual cutting is needed, finished the functions of 3D reconstruction and virtual cutting, thereby satisfy requirements of clinic and research.

VTK是面向对象的通用可视化类库，在科学和工程界有着广泛的应用，文中主要介绍交互式切割的意义以及VTK的可视化开发流程，并在此基础上讨论了两种交互式切割方式(Cropping和Clipping)的原理和实现方法，提出将其应用于医学教学、科研和临床诊断的虚拟切割中的设想，完成三维重建与虚拟切割的功能，从而满足临床与科研的需要。

Last, the design methods for unobscured, all-reflective three-mirror zoom optical system are discussed.

本文研制了大视场，大相对口径的离轴三反射镜系统，该系统视场（15°×2°），F数为2.2。

Theory that there are unobservable social structures that generate observable social phenomena.

认为一些可视的社会现象是由一些不可视的社会结构造成的人类学理论。

An anthropological theory that there are unobservable social structures that generate observable social phenomena.

认为一些可视的社会现象是由一些不可视的社会结构造成的人类学理论。

A meta-analysis showed that the combination of vasoconstrictor and endoscopic therapy is superior to endoscopic therapy alone for controlling AEVH.

综合分析显示，在急性食道静脉瘤出血的治疗，使用血管收缩剂合并内视镜的疗法比单独使用内视镜疗法优越。

Vax family was found in 1998, which is related to development of forebrain, optic vesicle, eye-predium, optic stalk and neuroretina.

Vax基因家族是新近发现的一类与视觉神经系统发育密切相关的同源异型盒基因，调控前脑、眼原基、视泡、视柄以及视网膜的发育。

Subjects had more serious symptoms, more quickly onset of vection and more short rotation time when they were lying.

不同强度视觉与前庭系统感觉冲突影响视运动错觉的发生时间和旋转耐受性，表现为冲突越强，视运动错觉发生的时间越早，旋转耐受时间越短；视觉与前庭神经系统感觉冲突的增加可加重晕动发生时的症状。

In contrast, many of the rods and cones survive in the ventral retina.

形成鲜明对比的是，位于视网膜腹侧的许多视杆视锥细胞存活下来。

In the virtual surgery system, the virtual scalpel could be manipulated on 3D liver mould with PHANTOM. The simulating effect was the same as the clinic operation for auxiliary partial orthotopic liver transplantation. Plane visualization of hepatic resection and intrahepatic vessel cutting was achieved by adjusting the transparency of the resection part. Life-like could be felt and power feeling could be touched during virtul operation. Conclusion ① The visualized liver mould reconstructed is 3D and verisimilar, and it is helpful to design reasonable scheme for liver transplantation.

在建立的虚拟手术系统的虚拟环境中，使用力反馈设备PHANTOM操纵"虚拟手术刀"模拟了辅助性部分原位肝移植的手术过程，其结果符合临床手术的效果；通过控制肝脏模型切除部分的透明度，使肝脏手术切割平面可视化以及肝脏内部管道手术切断平面可视化；手术模拟过程逼真，形象，且有"力"的感受。

You can increase or decrease a viewport's size after it's been created.

你可以在视埠被建立后，增加或减少一个视埠的尺寸。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。