NEW YORK — Mark Fleischman, the man who operated the favorite club of celebrities in the early 1980s at Studio 54, died Wednesday from assisted suicide. He was 82. Fleischman had reportedly been in poor health for several years. He was unable to walk or take care of himself, according to the BBC. After the first owners got sent to prison for tax evasion, Fleischman took over ownership in 1980 and managed the club until 1996. “From the very first night we opened, in 1981, I was swept up in a world of celebrities, drugs, power and sex,” he wrote in a book, “Inside Studio 54,” that was released i…