Given a passage with a question and an answer to that question, classify if the answer actually answers the question into 'yes' or 'no'. Output 'yes' if the answer answers the question and output 'no' if the answer does not answer the question.
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Question: Question: Is low serum bilirubin concentration a predictor of chronic kidney disease?
Answer: Our study demonstrated that serum total bilirubin concentration could be a novel risk factor for the progression of CKD, defined as eGFR <60 ml/min/1.73 m(2), in the general population.

Answer: yes


Question: Question: Does pharmacological preconditioning using intraportal infusion of L-arginine protect against hepatic ischemia reperfusion injury?
Answer: Pharmacological preconditioning with intraportal L-arginine provided protection against hepatic I/RI in early phases of the reperfusion period. The mechanisms underlying the protective effect may include preservation of the mitochondrial structure and inhibition of caspase-3 activity.

Answer: yes


Question: Question: Is systolic volume index by Doppler echocardiography an useful marker for stratification and prognostic evaluation in patients with severe aortic stenosis and preserved ejection fraction?
Answer: Patients with severe aortic stenosis, normal ejection fraction and low aortic flow have a worse prognosis. Analysis of aortic flow by Doppler echocardiography is useful in risk stratification and therapeutic decision-making in patients with aortic stenosis.

Answer:
yes