The technique of LAMMA micro mass spectrometry.

iterative model-building behaviour which consists of dividing the morphology of the specimens into putative radiation sources evaluating the division and then re-dividing the morphology again as necessary. This approach, the full possibilities of which are yet to be fully explored, permits in favourable cases the localization of radioactivity to extremely small features within cells. In practice, the methodology includes detailed measurements of certain aspects of the microanatomy of the cells-the methods being employed having much in common with those now widely exploited in tissue morphometry generally (Williams, 19776; Weibel 1979). The interpretation of extensively cross-fired images is in any case basically a stereological problem and the quantitative measurement of tissue structure uses stereological methods. The deployment of these techniques allows biochemical insight against the backcloth of quantitatively delineated cells and tissue structure. The methods and possibilities of these methodological and interpretational approaches are to be illustrated here by reference to several sorts of application of autoradiography including a study of peptide uptake and processing in kidney proximal-convoluted -tubule cells.