Instructions: 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.
Input: Question: Do s-100beta protein levels correlate with stroke in patients undergoing carotid endarterectomy under general anesthesia?
Answer: S-100 concentration slightly increased at the end of surgery and remained high until the first postoperative day in all patients. S-100 was not significantly different in the patients with postoperative stroke. S-100 did not serve as a marker for postoperative stroke after carotid artery surgery. This fact must be taken into account during further investigations of S-100.
Output:
no