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 chronic cerebrospinal venous insufficiency associated with chronic venous disorders : A case-control study?
Answer: We found no association of CCSVI with the presence of CVD or family history of varicose veins.

Answer: no


Question: Question: Is repeated sputum microscopy essential for monitoring tuberculosis treatment response?
Answer: The yield of a second on-the-spot sputum specimen is negligible, provided that the first smear is from an overnight specimen. From the data available, it is evident that repeated follow-up smears are not essential for documenting treatment outcome.

Answer: no


Question: Question: Does celecoxib induce epithelial-mesenchymal transition in epithelial ovarian cancer cells via regulating ZEB1 expression?
Answer: Our results indicated that Celecoxib might induce EMT and increase cellular invasiveness in ovarian cancer cells in vitro, which also implied that it needed a comprehensive evaluation in preclinical researches before introducing Celecoxib into the clinical regimen.

Answer:
yes