Large Contingent
Mostrando 13-21 de 21 artigos, teses e dissertações.
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13. Reward-dependent plasticity in the primary auditory cortex of adult monkeys trained to discriminate temporally modulated signals
Adult owl monkeys were trained to detect an increase in the envelope frequency of a sinusoidally modulated 1-kHz tone. Detection was positively correlated with the magnitude of the change in the envelope frequency. Surprisingly, neuronal responses recorded in the primary auditory cortex of trained monkeys were globally suppressed by the modulated tone. Howev
National Academy of Sciences.
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14. Analysis of Methods for Growth Detection in the Search for Extraterrestrial Life
In the search for life on other planets, experiments designed to detect the growth of microorganisms may prove to be definitive when coupled with chemical characterization and metabolic experiments. If organisms are not abundant, growth provides the only means for obtaining a large mass of biological material suitable for chemical compositional analyses and
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15. Induction of the Allantoin Degradative Enzymes in Saccharomyces cerevisiae by the Last Intermediate of the Pathway
Saccharomyces cerevisiae can degrade allantoin in five steps to glyoxylate, ammonia, and “CO2.” We previously demonstrated that synthesis of the urea carboxylase-allophanate hydrolase multienzyme complex is contingent upon the presence of allophanic acid, the product of the urea carboxylase reaction. Since these enzymes catalyze the last two reactions of
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16. Cloning and stable maintenance of DNA fragments over 300 kb in Escherichia coli with conventional plasmid-based vectors.
Bacterial artificial chromosome (BAC) and P1-derived artificial chromosome (PAC) systems were previously developed for cloning of very large eukaryotic DNA fragments in bacteria. We report the feasibility of cloning very large fragments of eukaryotic DNA in bacteria using conventional plasmid-based vectors. One conventional plasmid vector (pGEM11), one conve
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17. Abnormal activation of H+ conductance in NADPH oxidase-defective neutrophils.
To combat bacterial infection, phagocytes generate superoxide (O2-) and other microbicidal oxygen radicals. NADPH oxidase, the enzyme responsible for O2- synthesis, is deficient in chronic granulomatous disease (CGD) patients. Although O2- generation is accompanied by a large burst of metabolic acid production, intracellular pH (pHi) remains near neutrality
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18. Molecular characterization of the tdc operon of Escherichia coli K-12.
The nucleotide sequence of a 2-kilobase DNA fragment of the tdc region of Escherichia coli K-12, previously cloned in this laboratory, revealed two open reading frames, tdcC and ORFX, downstream from the tdcB gene (formerly designated tdc) encoding biodegradative threonine dehydratase. A 24-base-pair sequence separated tdcC from the dehydratase coding region
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19. Transient projection from the superior temporal sulcus to area 17 in the newborn macaque monkey.
Area 17 in the neonate of numerous species receives projections from cortical areas that do not project to area 17 in the adult. To investigate if this were the case in the developing primate, we have made injections of retrograde tracers in area 17 of newborn monkeys (Macaca irus) and examined the areal distribution of labeled neurons. Neurons projecting to
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20. HveA (Herpesvirus Entry Mediator A), a Coreceptor for Herpes Simplex Virus Entry, also Participates in Virus-Induced Cell Fusion
The purpose of this study was to determine whether a cell surface protein that can serve as coreceptor for herpes simplex virus type 1 (HSV-1) entry, herpesvirus entry mediator (previously designated HVEM but renamed HveA), also mediates HSV-1-induced cell-cell fusion. We found that transfection of DNA from KOS-804, a previously described HSV-1 syncytial (Sy
American Society for Microbiology.
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21. Localization of Boron in Cell Walls of Squash and Tobacco and Its Association with Pectin (Evidence for a Structural Role of Boron in the Cell Wall).
B deficiency results in a rapid inhibition of plant growth, and yet the form and function of B in plants remains unclear. In this paper we provide evidence that B is chemically localized and structurally important in the cell wall of plants. The localization and chemical fractionation of B was followed in squash plants (Curcurbita pepo L.) and cultured tobac