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CreatorTitleDescriptionSubjectDate
301 Adler, Frederick R.Alternating host cell tropism shapes the persistence, evolution and coexistence of Epstein-Barr virus infections in humanEpstein-Barr virus (EBV) infects and can persist in a majority of people worldwide. Within an infected host, EBV targets two major cell types, B cells and epithelial cells, and viruses emerging from one cell type preferentially infect the other. We use mathematical models to understand why EBV infec...2010
302 Jorgensen, ErikGenetic screens for synaptic function mutants in the nematode C. elegansThe synapse is the site of a remarkable conversion of electrical signals into chemical signals. This conversion takes place when a depolarizing impulse enters the axon terminal and opens voltage-sensitive calcium channels; calcium then flows into the cell and initiates the fusion of synaptic vesicle...Vesicle; Neurotransmission; Cell1996
303 Capecchi, Mario R.Targeted disruption of the even-skipped gene, evx1, causes early postimplantation lethality of the mouse conceptus.Implantation within the mammalian uterus elicits dramatic changes in the growth, differentiation, and morphogenesis of the conceptus. This process is interrupted in mice carrying a targeted disruption of the murine evx1 gene, a homolog of the Drosophila even-skipped (eve) gene. Upon implantation, pr...Extraembryonic; Homozygotes; Drosophila1994-08-15
304 Adler, Frederick R.Effects of intraspecific density-dependence on species richness and species abundance distributionsAbstract Species richness and patterns of abundance result from the interplay between niche differences, realized as intraspecific density-dependence (IDD), and so-called neutral processes that arise when species fitnesses are similar. This paper presents an extension of neutral models that incorpo...2010
305 Thomas, Kirk R.; Capecchi, Mario R.Introduction of homologous DNA sequences into mammalian cells induces mutations in the cognate gene.Injection of homologous DNA sequences into nuclei of cultured mammalian cells induces mutations in the cognate chromosomal gene. It appears that these mutations result from incorrect repair of a heteroduplex formed between the introduced and the chromosomal sequence. This phenomenon is termed 'heter...Animals; Cell Line; Drug Resistance, Microbial; Fibroblasts; Mice; Models, Genetic; Neomycin; Plasmids1986-11-06
306 Sperry, John S.Analysis of circular bordered pit function II. Gymnosperm tracheids with torus-margo pit membranesA model of xylem conduit function was applied to gymnosperm tracheids with torus-margo pit membranes for comparison with angiosperm vessels. Tracheids from 17 gymnosperm tree species with circular bordered pits and air-seed pressures from 0.8 to 11.8 MPa were analyzed. Tracheids were more reinforced...Functional wood anatomy; hydraulic architecture; plant biomechanics2004
307 Olivera, Baldomero M.Biochemical studies of ω-conotoxin GVIA; a peptide toxin inhibiting voltage-sensitive Ca++ channelsThe fish-hunting cone snails use their venom to quickly paralyze their more agile prey. In the last few years, our laboratories have carried out a program of analyzing biologically active components present in the fish-hunting cone snail venoms (Cruz et al. 1985; Olivera et al. 1985). We have concen...Conotoxins; Calcium channels; Conus geographus; Venom1987
308 Davidson, Diane W.Experimental study of diffuse competition in harvester antsExperiments carried out over a 5-yr period in the Chihuahuan Desert support the a priori prediction of diffuse competition between two species of harvester ants. Despite dietary overlap between a large species {Pogonomyrmex rugosus) and a small species (Pheidole xerophila), the large species facilit...Chihuahuan Desert; Ants; Facilitation; Resource allocation; Granivory1985
309 Bastiani, MichaelGuidance of neuronal growth cones in the grasshopper embryo. I. Recognition of a specific axonal pathway by the pCC neuronThe selective affinities that growth cones display for specific axonal surfaces give rise to stereotyped patterns of selective fasciculation. Previous studies on cell recognition by neuronal growth cones in the grasshopper embryo led to the proposal and initial experimental testing of the labeled-p...Fascicle; Axon; Affinity1986
310 Capecchi, Mario R.Gene targeting. How efficient can you get?With targeting in Leishmania and Trypanosoma, there are now greater incentives to develop the technology in organisms of intermediate complexity such as Caenorhabditis elegans and Drosophila. The ratio of homologous to nonhomologus recombination in these organisms might prove to be greater than in m...Animals; DNA Mutational Analysis; Recombination, Genetic1990-11-08
311 Olivera, Baldomero M.Poly(ADP-ribosylation) of DNA topoisomerase I from calf thymusWe demonstrate that the activity of the major DNA topoisomerase I from calf thymus is severely inhibited after modification by purified poly(ADP-ribose) synthetase. Polymeric chains of poly(ADP-ribose) are covalently attached to DNA topoisomerase I. These observations with highly purified enzymes ...ADP-ribosylation; Poly(ADP-ribose) synthetase1984
312 Davidson, Diane W.Experimental manipulation of food bodies in CecropiaNeotropical Cecropia trees range from Mexico to Argentina and are typical of disturbed habitats. Cecropia plants provide food and housing for the ants in return for known or presumed protection from herbivores and vine cover. Glycogen-rich Mullerian bodies (MB's) are the predominant food source for ...Mullerian bodies; Trichilia; Cecropia tessmannii; Cecropia pungara1992
313 Davidson, Diane W.Nonnative brome grasses in the new national monumentIncluded within the boundaries of the Grand-Staircase Escalante National Monument are a number of noxious weeds for which the BLM mandates control. In addition to listed weeds are nonnative brome grasses [Bromus tectorum and Bromus rubens), which can potentially convert native ecosystems to biologic...Noxious weeds, Cheatgrass,1998
314 Davidson, Diane W.Herbivory on planted dipterocarp seedlings in secondary logged forests and primary forests of Sabah, MalaysiaLeaf defences, leaf nutritional quality and leaf expansion rates may vary with resource availabilities to plants. Such variation could affect rates of leaf loss to herbivores, particularly along the steep resource gradients in disturbed forests. Intraspecific and interspecific variation in leaf dama...Danum Valley; Dipterocarp; Dryobalanops lanceolata; Herbivory rates; Leaf damage; Leaf expansion rates; Logged tropical forests; Secondary forests; Shorea leprosula2001-03
315 Davidson, Diane W.Experimental studies of species-specificity in cecropia-ant relationshipsStrict coevolution requires that interactions among organisms be speciesspecific. We assessed the relative roles of host- and habitat-specificity in determining the match between a genus of myrmecophytic trees and a guild of obligate plant-ants in the moist tropical forests of Madre de Dios, Peru. F...Ant-plant; Ants; Cecropia; Coevolution; Colonization; Coordinated dispersal; Ecological fitting; Habitat-specificity; Host-specificity; Mutualism; Parasitoid wasps; Preadaptation1997
316 Olivera, Baldomero M.Conus peptides: phylogenetic range of biological activityThe major function of the venoms of the predatory marine snails belonging to the genus Conus is to paralyze prey. Thus, the venom of each Conus species acts on receptors and ion channels of the prey; previous studies suggested much less activity on homologous receptor targets in more distant taxa....Conus peptides; Conopeptides; Conotoxins1992
317 Coley, Phyllis D.Uprooting and snapping of trees: structural determinants and ecological consequencesThe influence of mechanical and architectural properties of trees on growth rates, mortality rates, and relative probabilities of snapping and uprooting were examined on Barro Colorado Island, Republic of Panama. Of 310 fallen trees, 70% snapped, 25% uprooted, and 5% broke off at ground level. Stepw...Snapping; Uprooting1983
318 Sperry, John S.Embolized conduits of rice (Oryza sativa, poaceae) refill despite negative xylem pressureEmbolism reversal in rice plants was studied by testing the plant's ability to refill embolized conduits while xylem pressures were substantially negative. Intact, potted plants were water-stressed to a xylem pressure of -1.88 + 0.1 MPa and a 66.3 + 3.8% loss of xylem conductivity (PLC) by cavitatio...Embolism; novel revilling; Oryza2005
319 Adler, Frederick R.Plant signalling: The opportunities and dangers of chemical communicationThe notion of chemical communication between plants and other organisms has gone from being viewed as a fringe idea to an accepted ecological phenomenon only recently. An Organized Oral Session at the August 2010 Ecological Society of America meeting in Pittsburgh examined the role of plant signall...2011
320 Bastiani, MichaelDevelopmental expression of REGA-1, a regionally expressed glial antigen in the central nervous system of grasshopper embryosGlial cells are a large component of the developing nervous system, appearing before the onset of axon outgrowth in a variety of developing systems. Their time of appearance and their location in conjunction with developing axon pathways may allow them to define the position of axon pathways.Antibody; Axons; Pathways1991
321 Capecchi, Mario R.Targeted mutations in hoxa-9 and hoxb-9 reveal synergistic interactions.Mice were generated with a targeted disruption of the homeobox-containing gene hoxb-9. Mice homozygous for this mutation show defects in the development of the first and second ribs. In most cases the first and second ribs are fused near the point at which the first and second pairs of ribs normally...Embryonic and Fetal Development; In Situ Hybridization; Mice, Knockout1997-01-15
322 Olivera, Baldomero M.On a potential global role for vitamin K-dependent γ-carboxylation in animal systemsThe vitamin K-dependent γ-carboxylation of glutamate to γ-carboxyglutamate was originally well characterized in the mammalian blood clotting cascade. γ-Carboxyglutamate has also been found in a number of other mammalian proteins and in neuropeptides from the venoms of marine snails belonging to...Carboxylation; Glutamate; Carboxyglutamate; Carboxylase mRNA; Conantokin G2001
323 Jorgensen, ErikCaenorhabditis elegans rab-3 mutant synapses exhibit impaired function and are partially depleted of vesiclesRab molecules regulate vesicular trafficking in many different exocytic and endocytic transport pathways in eukaryotic cells. In neurons, rab3 has been proposed to play a crucial role in regulating synaptic vesicle release. To elucidate the role of rab3 in synaptic transmission, we isolated and cha...1997
324 Olivera, Baldomero M.; Hillyard, David R.Heterodimeric structure of the spider toxin ω-Agatoxin IA revealed by precursor analysis and mass spectrometryWe report the first molecular characterization of a precursor sequence for a small, Ca2+ channel blocking, peptide spider toxin, ω-agatoxin IA. By integrating information generated from a molecular genetic approach using agatoxin cDNAs with data provided from mass spectrometry of the mature tox...Spider toxin w-Aga-IA; Heterodimeric structure1992
325 Goller, FranzExperimental support for a model of birdsong productionIn this work we present an experimental validation of a recently proposed model for the production of birdsongs. We have previously observed that driving the model with simple functions of time, which represent tensions in vocal muscles, produces a wide variety of sounds resembling birdsongs. In th...Vocal; Muscles; Syrinx2003
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