title: The estimation of the time of death by non-protein nitrogen (NPN) in cadaveric materials. Report 3: multiple regression analysis of NPN values in human cadaveric materials.
abstract: The non-protein nitrogen (NPN) values in brain, lung, liver, and kidney in 79 autopsy cases were determined according to the Micro-Kjeldahl Nessler method. Multiple regression analysis of the data was performed with every possible combination of the time of death and the NPN values in the tissues. The brain NPN showed the best correlation with the postmortem time (r = 0.673), whereas the other correlations were less satisfactory (lung r = 0.422, liver r = 0.397, and kidney r = 0.379, respectively). However, multiple combinations of each tissue NPN value proved to give better correlation coefficients and smaller errors of the estimated time of death. The practical significance of the tissue NPN as a postmortem biochemical indicator of the time of death and the multiple regression analysis of such indicators were extensively discussed in this report.
mesh_terms: D000293:Adolescent; D000328:Adult; D001923:Brain Chemistry; D002648:Child; D002675:Child, Preschool; D005554:Forensic Medicine; D006801:Humans; D007223:Infant; D007668:Kidney / Q000032:analysis; D008099:Liver / Q000032:analysis; D008168:Lung / Q000032:analysis; D008875:Middle Aged; D009584:Nitrogen / Q000032:analysis*; D012044:Regression Analysis
chemical_list: D009584:Nitrogen