Designing MOSFET bridge rectifiers for high voltages
This is based on Dave Tweed's now deleted circuit with 4 added diodes.

The diodes in series with the 10k resistors drive the FETs on only when Vmains is above V_DC_out for a given FET by Vf_diode + Vth_FET.  



Diagram is a hacked about cut and paste version of Dave Tweed's diagram. 

Dave Tweed said:

If you use, say, 10 V 400 mW zeners, they can handle an average current of 40 mA. 10k resistors let you handle around 400 V.

But pay attention to the power dissipation in the resistors, too. Larger values of resistance will dissipate less power, but they'll also slow down the switching somewhat.