Mr

Symbol for molecular weight ratio or relative molecular mass.

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Maddox rods; magnetic resistance; magnetic resonance; mandibular reflex; mannose-resistant; may repeat; measles and rubella; medial raphe; medial rectus [muscle]; medical record; medical release; medium range; megaroentgen; mental retardation; metabolic rate; Metathesaurus relational file [UMLS]; methemoglobin reductase; methyl red; mineralocorticoid receptor; mitral reflux; mitral regurgitation; modulation rate; molar refraction; molecular response; mortality rate; mortality ratio; multicentric reticulohistiocytosis; multire-gression; muscarinic receptor; muscle receptor; muscle relaxant; myocardial revascularization

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MR abbr magnetic resonance

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relative molecular mass; see molecular weight, under weight.