Ischemic ATN occurs when the tubular cells do not get enough oxygen, a condition that they are highly sensitive and susceptible to, due to their very high metabolism. Diagnosis. Acute tubular necrosis is classified as a renal (i.e. not pre-renal or post-renal) cause of acute kidney injury. Diagnosis is made by a FENa (fractional excretion of sodium) > 3% and presence of muddy casts (a type of granular cast) in urinalysis.
A Rhyming Couplet is two line of the same length that rhyme and complete one thought. There is no limit to the length of the lines. Rhyming words are words that sound the same when spoken, they don't necessarily have to be spelt the same.
The poem also rhymes, and therefore it has a rhyme scheme. In this poem, the rhyme scheme is: AABB. This means that in each four-line stanza, the first two lines rhyme (their rhyming sound is indicated with an A), and the last two lines rhyme (B). These rhyming pairs are called couplets, probably because they are like little verbal couples.