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.
Q: Question: Is n-methyl-D-aspartate receptor channel block by meperidine dependent on extracellular pH?
Answer: At acidic pH the potency of meperidine for N-methyl-D-aspartate-receptor channels was increased. Any antinociceptive and neuroprotective benefit from the N-methyl-D-aspartate-receptor antagonist property of meperidine may be pH dependent.
A:
yes