326588 OR open surgery 47 329014 O-R oscillating-rotating 28 326344 OR operator 17 327927 O-R oxidation-reduction 7 325395 OR Oregon-R 6 330438 O-R outcome-response 4 330436 O-R oxidative-reductive 2 330439 O-R origin of ASMA to retinaculum 1 330440 O-R original to revised condition 1 330441 O-R orlistat-resveratrol 1 330437 O-R oto-respiratory 1