title: The "omics" haystack: defining sources of sample bias in expression profiling.
authors.forename: O John
authors.initials: OJ
authors.lastname: Semmes
mesh_terms: D015982:Bias; D020869:Gene Expression Profiling / Q000592:standards* / Q000706:statistics & numerical data; D006801:Humans; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods