Sloth
Mostrando 25-31 de 31 artigos, teses e dissertações.
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25. Molecular phylogeny of the extinct ground sloth Mylodon darwinii.
DNA was extracted from the remains of 35 ground sloths from various parts of North and South America. Two specimens of Mylodon darwinii, a species that went extinct at the end of the last glaciation, yielded amplifiable DNA. However, of the total DNA extracted, only approximately 1/1000 originated from the sloth, whereas a substantial part of the remainder w
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26. Ancient DNA: extraction, characterization, molecular cloning, and enzymatic amplification.
Several chemical and enzymatic properties were examined in the DNA extracted from dry remains of soft tissues that vary in age from 4 to 13,000 years and represent four species, including two extinct animals (the marsupial wolf and giant ground sloth). The DNA obtained was invariably of a low average molecular size and damaged by oxidative processes, which p
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27. Asynchronous extinction of late Quaternary sloths on continents and islands
Whatever the cause, it is extraordinary that dozens of genera of large mammals became extinct during the late Quaternary throughout the Western Hemisphere, including 90% of the genera of the xenarthran suborder Phyllophaga (sloths). Radiocarbon dates directly on dung, bones, or other tissue of extinct sloths place their “last appearance” datum at ≈11,0
National Academy of Sciences.
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28. Ancient DNA from giant extinct lemurs confirms single origin of Malagasy primates
The living Malagasy lemurs constitute a spectacular radiation of >50 species that are believed to have evolved from a common ancestor that colonized Madagascar in the early Tertiary period. Yet, at least 15 additional Malagasy primate species, some of which were relative giants, succumbed to extinction within the past 2,000 years. Their existence in Madagasc
National Academy of Sciences.
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29. The Origin of Human Chromosome 1 and Its Homologs in Placental Mammals
Developing ordered gene maps from multiple mammalian species coupled with chromosome-painting data provide a powerful resource for resolving the evolutionary history of chromosomes and whole genomes. In this work, we recapitulate the evolutionary history of human chromosome 1 and its homologs in placental mammals, putatively the largest physical unit in
Cold Spring Harbor Laboratory Press.
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30. Dimerization and Template Switching in the 5′ Untranslated Region between Various Subtypes of Human Immunodeficiency Virus Type 1
The human immunodeficiency virus type 1 (HIV-1) particle contains two identical RNA strands, each corresponding to the entire genome. The 5′ untranslated region (UTR) of each RNA strand contains extensive secondary and tertiary structures that are instrumental in different steps of the viral replication cycle. We have characterized the 5′ UTRs of nine di
American Society for Microbiology.
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31. Simulation Model of the Coupling between Nitrification and Denitrification in a Freshwater Sediment
A model was constructed to simulate the results of experiments which investigated nitrification and denitrification in the freshwater sediment of Lake Vilhelmsborg, Denmark (K. Jensen, N. P. Sloth, N. Risgaard-Petersen, S. Rysgaard, and N. P. Revsbech, Appl. Environ. Microbiol. 60:2094-2100, 1994). The model output faithfully represented the profiles of O2 a