00342pab a2200121 454500008004000000100001700040245009200057260000900149300001200158362000800170650002000178773002200198180718b2001   xxu||||| |||| 00| 0 eng d  aFrenk, Julio  aDeterminants of medical employment in urban Mexico: ascription, achievement and context  c2001  ap.79-95  aMay  aHealth services  aCurrent Sociology