NEWYORK(Reuters)-ThesmallestofgainsgavetheStandard&Poor's500itsseventhstraightwinningdayonThursday,buttheindexfailedtoholdabovethe1,500line,restrainedbyApple'sworstdayinmorethanfouryears.AppleIncslid12.4percentto$450.50adayafteritpostedrevenuethatmissedWallStreet'sforecastasiPhonesaleswerepoorerthanexpected.Thesharpdropwipedoutnearly$60billioninApple'smarketcapitalizationto...