title: [Isotope effects in biological processes--variation of 13C and 15N abundance in the biosphere].
mesh_terms: D000818:Animals; D001823:Body Composition; D002247:Carbon Isotopes / Q000032:analysis*; D004777:Environment; D006801:Humans; D009587:Nitrogen Isotopes / Q000032:analysis*; D010944:Plants / Q000032:analysis; D014867:Water / Q000032:analysis
chemical_list: D002247:Carbon Isotopes; D009587:Nitrogen Isotopes; D014867:Water