TASK DEFINITION: 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.
PROBLEM: Question: Are the receptors for gibbon ape leukemia virus and amphotropic murine leukemia virus downregulated in productively infected cells?
Answer: A-MLV or GALV receptors remain on the surface of chronically infected cells and are detectable by respective antibodies, indicating that these receptors are not downregulated in these infected cells as previously proposed. We were also able to detect viral envelope proteins on the infected cell surface and infected cells are unable to bind soluble A-MLV or GALV envelopes indicating that receptor binding sites are masked by endogenously expressed A-MLV or GALV viral envelope. However, receptor masking does not completely prevent A-MLV or GALV superinfection.

SOLUTION: no

PROBLEM: Question: Is assessment of joint space narrowing with conventional standing antero-posterior radiographs : relief in mild-to-moderate pain a confounder in recent osteoarthritis structure-modifying drug trials?
Answer: Knee pain relief did not bias the report of a structure-modifying effect of glucosamine sulfate in two recent long-term trials, possibly due to the mild-to-moderate patient characteristics. Consensus deliverables should acknowledge that the potential limitations of conventional standing antero-posterior radiographs should not be overestimated since they may not apply to all patient populations and to all studies using this gold standard technique.

SOLUTION: no

PROBLEM: Question: Is epidemic MRSA clone ST22-IV more resistant to multiple host- and environment-related stresses compared with ST228-I?
Answer: Our results support our hypothesis that ST22-IV has a fitness advantage over ST228-I. This fitness advantage could have allowed ST22-IV to displace ST228-I without acquiring additional resistances and could help explain its epidemic success in hospital settings and its spread in Europe and beyond.

SOLUTION:
yes