A proportion may pertain-to an isotope.Logical formLearned from13 sentences. Studies can be constituted-of-or-filled-with isotopes.Logical formLearned from13 sentences. Isotopes may pertain-to elements.Logical formLearned from13 sentences. A shortage can be constituted-of-or-filled-with isotopes.Logical formLearned from13 sentences. Isotopes can be for medical uses.Logical formLearned from13 sentences. Isotopes may pertain-to an element.Logical formLearned from12 sentences. Isotopes may undergo abundances.Logical formLearned from12 sentences. Some isotopes can be constituted-of-or-filled-with plutonium.Logical formLearned from12 sentences. Isotopes may undergo concentrations.Logical formLearned from12 sentences. Isotopes can be constituted-of-or-filled-with iodine.Logical formLearned from12 sentences. Shortages can be constituted-of-or-filled-with (radio isotopes).Logical formLearned from12 sentences. A demand can be for medical isotopes.Logical formLearned from12 sentences. Deuterium can be an isotope of hydrogen.Logical formLearned from12 sentences. Isotopes may be used in medicine.Logical formLearned from12 sentences. Organisms may prefer isotopes.Logical formLearned from12 sentences.