Urine collects in the renal pelvis and then heads out of the kidney through the ureter.

尿液在肾盂中聚集，然后通过输尿管排出肾脏。

In grade III, urine fills and begins to stretch both the ureter and the renal pelvis.

尿液的充盈开始导致输尿管和肾盂扩张。

The renal papilla project into minor calyces which join together to form major calyces which funnel into the renal pelvis.

肾乳头突入肾小盏，每2-3个肾小盏合成肾大盏；2-3个肾大盏合并形成漏斗形的肾盂。

In grade II, urine fills the entire ureter and the renal pelvis, the center part of the kidney.

尿液充满整个输尿管和肾盂，即肾的中心部分。

There are three major regions of the kidney, cortex, medulla and the renal pelvis.

皮质、髓质和肾盂。外层的颗粒状层是肾皮质。

Once millions of nephrons have each made urine, it flows into the minor calyces, then major calyces, and finally into the renal pelvis.

当数以百万计的肾单位各自都产生尿液，尿液便流入肾小盏，然后是肾大盏，最终进入肾盂。

In grade IV, the ureter is so swollen that it begins to get curvy and the renal pelvis and calyces—the urine collection ducts—become moderately swollen and distorted.

输尿管过于肿胀，甚至开始产生卷曲，肾盂、肾盏和集合管发生中度肿胀和扭曲。