How to prove the following version of the Hilbert basis theorem:

$R$ is Noetherian if and only if $R[|x|]$ is Noetherian.

Of course, in view of the isomorphism: $$\frac{R[|x|]}{(x)~R[|x|]} \simeq R$$ one direction follows. I'm struggling to come up with a proof for the converse. Any help is much appreicated.