1. A magnetic resonance imaging system, comprising: a denoising unit configured to denoise a partially reconstructed image and provides a measure of a denoising effectivity, the denoising effectivity comprising an estimate of an amount of information relating to anatomical structure that has been removed, or damaged, or affected by the denoising unit; and a reconstruction unit configured to iteratively reconstruct received parallel MR data with a parallel imaging reconstruction technique and, in subsequent iterations, the denoised partially reconstructed image and the measure of the denoising effectivity to generate an output image.