英语语法分析

Gastroesophageal reflux is the most common cause of vomiting in infants.

胃食管反流是婴儿呕吐的最常见的原因。

The primary tumor was at the gastroesophageal junction in 20% and was poorly differentiated in 60%.

原发性肿瘤20%位于胃食管结合部，还有60%分类很差。

Objective To investigate the gastric electrical activity changes in gastroesophageal reflux disease(GERD).

目的探讨胃食管反流病（GERD）的胃电活动变化。