英文医学科普｜肾结石
The urinary tract includes the kidneys, ureters, bladder and urethra. Within each kidney, urine flows from the outer cortex to the inner medulla. The renal pelvis is the funnel through which urine exits the kidney and enters the ureter.
As urine can become very concentrated as it passes through the kidneys. When the urine becomes too concentrated, calcium, uric acid salts and other chemicals dissolved in the urine can crystallize, forming a kidney stone (renal calculus).
Usually the calculus is the size of a small pebble. But ureters are very sensitive to being stretched, and when stones form and distend it, the stretching can be very painful. Often, people may not know they have kidney stones until they feel the painful symptoms resulting from a stone being stuck anywhere along the urinary tract. Fortunately, small stones typically pass out of the kidneys and through the ureters on their own without causing any problems.
However, stones can become more problematic when they block the flow of urine. A staghorn kidney stone may obstruct the entire kidney. Fortunately, these stones are the exception rather than the rule.
重点词汇汇总：
ureter /jʊ'ritɚ/n. 尿管；[解剖] 输尿管
urethra /jʊˈriːθrə/n. [解剖] 尿道
outer cortex外皮质区 /ˈkɔːrteks/n. [解剖] 皮质；树皮；果皮
medulla /mɪ'dʌlə/n. 髓质
renal pelvis肾盂
funnel /ˈfʌnl/n. 漏斗；漏斗状物；烟囱
concentrated /ˈkɑːnsntreɪtɪd/v. 集中（concentrate的过去分词）adj. 集中的；浓缩的；全神贯注的
uric acid salts 尿酸盐
crystallize /ˈkrɪstəlaɪz/vt. 使结晶；明确
kidney stone (renal calculus)肾结石(肾结石)
calculus /ˈkælkjələs/n. [病理] 结石；微积分学
pebble/ˈpebl/n. 卵石；水晶透镜vt. 用卵石铺
distend /dɪˈstend/vt. 使…膨胀；使…扩张vi. 扩张；膨胀
problematic /ˌprɑːbləˈmætɪk/adj. 问题的；有疑问的；不确定的
block the flow of urine阻止尿液流动
staghorn /'stæɡ,hɔrn/n. 石松；雄鹿角；一种大珊瑚
these stones are the exception rather than the rule.这些石头是例外而不是常规。
百度翻译：
尿路包括肾脏、输尿管、膀胱和尿道。在每个肾内，尿液从外皮质流向内髓质。肾盂是尿液流出肾脏进入输尿管的漏斗。
因为尿液在通过肾脏时会变得非常浓缩。当尿液过于浓缩时，溶解在尿液中的钙、尿酸盐和其他化学物质会结晶，形成肾结石（肾结石）。
结石通常只有一个小鹅卵石大小。但是输尿管对拉伸非常敏感，当结石形成并扩张时，拉伸会非常痛苦。通常，人们可能不知道他们有肾结石，直到他们感到疼痛的症状，结石被卡在任何地方沿尿路。幸运的是，小结石通常会自行排出肾脏和输尿管，不会造成任何问题。
然而，当结石阻碍尿液流动时，会变得更麻烦。鹿角形肾结石可能会阻塞整个肾脏。幸运的是，这些石头是例外而不常见。