Among the younger players listed are Santos sensation Neymar,Robert Griffin III Redskins Jersey, Milan forward Alexandre Pato,Dustin Keller Youth Jersey, Manchester United defender Rafael and Tottenham's Sandro.
Menezes will cut the squad to 35 in June before selecting his final 18 on July 6.
Ronaldinho has been included in a preliminary Brazil squad for the London Olympics that also includes David Luiz and Dani Alves.
Ronaldinho, Luiz and Alves are among a number of high-profile players over the age of 23 on coach Mano Menezes' list of 52 players,Antonio Brown Youth Jersey, with Inter Milan goalkeeper Julio Cesar,Sean Lee Jersey, AC Milan defender Thiago Silva and Porto forward Hulk also included.
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Only three players over the age of 23 can be included in the final 18-man squad.
The men's Olympic football tournament takes place from July 26 to August 11,Dustin Keller Jersey, keeping European-based players out of their club's pre-season camps.
Ronaldinho, who turns 32 next Wednesday and now plays for Flamengo, won Olympic bronze with Brazil in 2008, but the competition is the only major prize in world football the country has not won,Champ Bailey Jersey.