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Biomedical subjects

N Kaplan

Publications and source records attributed to N Kaplan.

At least 73 records · Page 4Linked to original sources

An improved method for estimating sequence divergence of DNA using restriction endonuclease mappings.

The method proposed by Kaplan and Langley for estimating the extent of sequence divergence between related DNA's using restriction endonuclease maps is modified so that the estimates are easier to compute. In the two-species case, these modifications lead via a maximum likelihood approach to an estimate which is closely related to one recently suggested by Nei and Li (1979) and Gotoh et al. (1979). Simulation studies show that the modified estimates are comparable to those of Kaplan and Langley, providing that there is sufficient homology in the DNA segments of the related species. The M-species case, M greater than or equal to 3, is also discussed.

Animals↗

Statistical analysis of the Ames Salmonella/microsome test.

A family of statistical models for analysis of Ames Salmonella/microsome test data is constructed that considers mutation and toxicity as competing risks and allows hyper-Poisson variability. These models have a parameter than can be employed as a mutagenic index because it approximates the slope at zero dose of a dose-response curve adjusted for toxicity. A second parameter quantifies plate-to-plate variability and lends itself to the study of factors affecting internal test reproducibility. The detection of aberrant plate counts is also addressed. This methodology is illustrated with data from a Salmonella test.

Animals↗

A new estimate of sequence divergence of mitochondrial DNA using restriction endonuclease mappings.

A new estimate of the sequence divergence of mitochondrial DNA in related species using restriction enzyme maps is constructed. The estimate is derived assuming a simple Posisson-like model for the evolutionary process and is chosen to maximize an expression which is a reasonable approximation to the true likelihood of the restriction map data. Using this estimate, four sets of mitochondrial DNA data are analyzed and discussed.

Animals↗