LOS ANGELES (AP) — CBS created its own version of March madness, earning a weekly ratings victory with college basketball and country music awards.Besides scoring with special events last week, the network had a monopoly on dramas and sitcoms in the top 10, led by "NCIS" and including "The Big Bang Theory."Leonard Nimoy lent his Mr. Spock voice to "Big Bang," haunting Jim Parsons' Sheldon for breaking a vintage "Star Trek" toy.ABC was CBS' nearest competitor in total viewers for the week of March 26, according to Nielsen Co. ratings released Tuesday.