Inverted output! Isn't that a DTL NOR gate? Reverse the diodes, delete R2, make R1 a pull-up, and you have a DTL NAND gate.
As DRL (Diode-Resistor-Logic), without the transistor, it would be an OR gate. Reverse the diodes, with a pullup resistor on the output, and you have a DRL AND gate.
With a pull-down resistor it acts as an OR gate. But it will be slower than a standard OR gate so you don't want to use it if you are concerned about speed.
I dont know, I'm just talking in general, whats the difference between the two anyway> ? i hope they can get along with each other, i think im using a little of both in my circuit