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.

Example Input: Question: Does nitric acid passivation affect in vitro biocompatibility of titanium?
Answer: Although the protocol for passivation used here could interfere with the pattern of ions released from Ti-6Al-4V and cpTi surfaces, the present study did not show any effect of this surface treatment on in vitro biocompatibility of Ti as evaluated by osteoblast attachment, proliferation, and differentiation.
Example Output: no

Example Input: Question: Do alpha-2 adrenoreceptors probably mediate the immobility produced by inhaled anesthetics?
Answer: Although stimulation (agonism) of alpha-2 adrenoreceptors can decrease the inhaled anesthetic concentration required to produce immobility in the face of noxious stimulation, blockade of alpha-2 adrenoreceptors minimally affects the concentration. Thus, augmentation of the effect of alpha-2 adrenoreceptors is not an appreciable part of the mechanism whereby inhaled anesthetics produce immobility.
Example Output: no

Example Input: Question: Does cleistocalyx nervosum extract ameliorate chemical-induced oxidative stress in early stages of rat hepatocarcinogenesis?
Answer: CE appeared to exert its chemopreventive effects by modulating antioxidant status during DEN and PB induced early stages of hepatocarcinogenesis in rats.
Example Output:
yes