Is it permissible for a female doctor to treat men in her private clinic when there are male doctors specializing in the area?

The question of a woman treating men has been answered previously (under fatwa no. 35124). The questioner is advised to dedicate her clinic to women, which would be a commendable effort and a great service to her sisters, reducing their need to go to men's clinics. This act, done with a sincere intention, is considered one of the greatest acts of devotion.