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Full-Text Articles in Life Sciences
Conservation And Variation Of Nucleotide Sequences In Escherichia Coli Strains Isolated From Nature, Lawrence G. Harshman, Monica Riley
Conservation And Variation Of Nucleotide Sequences In Escherichia Coli Strains Isolated From Nature, Lawrence G. Harshman, Monica Riley
Lawrence G. Harshman Publications
A group of Escherichia coli isolates from nature were compared with one another and with laboratory strains of E. coli with respect to size distribution of chromosomal restriction endonuclease fragments and differences in nucleotide sequences in selected small portions of the genomes. The estimated frequency of base substitutions in nucleotide sequences in and near the trp operons of 26 of the 28 E. coli strains examined ranged from 0.008 to 0.066. Nucleotide sequences in or near λ prophage homologs were significantly more variable than the sequences in or near trp, tnaA, and thyA genes. Thus, the λ-homologous regions …
Heterosis And Breed Effects In Swine, R. K. Johnson
Heterosis And Breed Effects In Swine, R. K. Johnson
Department of Animal Science: Faculty Publications
An objective of the NC-103 regional swine breeding project is to evaluate inter-population and intra-population performance of domestic and exotic strains of swine. Several cooperating stations have conducted experiments relative to this objective. Projects were not exact replicates, but sufficient overlap allowed combining the information to yield more precise estimates of heterosis and breed effects than was possible from the analyses of data from any single experiment. This publication summarizes data available from NC-103 cooperating stations on breed and heterosis effects in swine. An extensive crossbreeding experiment has been conducted and results published by Canadian researchers Fahmy and Bernard, 1971 …
Apparent Chromosomal Heterosis In A Fossorial Mammal, John C. Patton, Robert J. Baker, Hugh H. Genoways
Apparent Chromosomal Heterosis In A Fossorial Mammal, John C. Patton, Robert J. Baker, Hugh H. Genoways
University of Nebraska State Museum: Mammalogy Papers
For the past decade, numerous investigators have attempted to explain the plethora of genetic polymorphism found in nature (see Ayala 1976). However, few researchers have been able to document how polymorphisms have been maintained, whether the polymorphisms were genic or chromosomal. Our investigations into the maintenance of a Robertsonian chromosomal polymorphism in the plains pocket goher, Geomys bursarius major, have revealed evidence that this polymorphism is maintained by differential viabilities of the three chromosomal morphs, with the heterozygote being favored.