两个一组

Observe the healing time, time of hospitalization, first defecating time, defecating state in one week, one month and three months post operation, awareness of defecation, the ability of defecation controlling, the complication rate associated with creating of stoma, etc.

观察两组病例切口愈合时间、住院时间、首次排便时间；术后一周、一个月、三个月人工肛门排便情况；排便前是否有便意；自主控制排便的能力；与造口有关的并发症发生率等。

The Ecoserial device is a digital economiser with differential pressure gauge able to pilot until 204 valves by connecting itself to a pneumatic driving module RPB with only two threads.

节能控制仪是一数码并内置有压差器的脉冲阀控制仪，最多能控制到204个脉冲阀，而这也只要用两根管子与 RPB 先导阀盒组串连起来就可以达到。

In a randomized,placebo-controlled study, 30 pediatric patients undergoing openheart surgery were randomly assigned to one of two equal groups.

在一项随机安慰剂对照的研究中，将30个行开心手术的患儿随机平分到两组中。

This is a perennial difficulty, explains Neil Dodgson, an expert on 3-D screens at Cambridge University."Film-makers have traditionally tended to overdo 3-D effects in order to show off the technology," he says. If the two sets of muscles in your eyes are overworked as a result of keeping up with the 3-D, your brain receives conflicting signals and you begin to feel sick.

这是一个长久性的难题&，一位剑桥大学三维屏幕的研究专家尼格尔森说&如果你眼睛上的两组肌肉为了个跟上三维的画面而过度工作，你的大脑就会接收到不一致的信号你就会开始感到眩晕。

But we don't care about Battlegrounds.

但我们并不在乎沙场中的显露。

Ah! don't mention it, the butcher's shop is a horror.

啊！不用提了。提到肉，真是糟透了。