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.

Ex Input:
Question: Is plasminogen activation by fibroblasts from periodontal ligament and gingiva directly affected by chemokines in vitro?
Answer: These results suggest that plasminogen activation by PDL and GF is not directly affected by the chemokines even in the presence of the inflammatory mediators TGF-beta and IL-1.

Ex Output:
no


Ex Input:
Question: Does diabetes influence oral oncogenesis through fibroblast growth factor receptors?
Answer: It seems that diabetes does not affect the FGFR-2 and FGFR-3 pattern of expression throughout the various stages of oral oncogenesis.

Ex Output:
no


Ex Input:
Question: Is percutaneous biliary drainage oncologically inferior to endoscopic drainage : a propensity score matching analysis in resectable distal cholangiocarcinoma?
Answer: Compared with EBD, PTBD increases the incidence of seeding metastasis after resection for distal cholangiocarcinoma and shortens postoperative survival.

Ex Output:

yes