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CreatorTitleDescriptionSubjectDate
26 Olivera, Baldomero M.Preliminary study of Conus venom proteinALTHOUGH THE TOXICITY of venoms of the genus Conus has been known since a report by RUMPHIUS in 1705 (VAN BENTHEM-JUTTINO, 1959), these venoms have been studied only intermittently since. Biochemical studies have not been carried out to any great extent; the last major study on the biochemistry of...Conotoxins; Conus venom1976
27 Davidson, Diane W.Species diversity and community organization in desert seed-eating antsPatterns of species diversity and community organization in desert seed-eating ants were studied in 10 habitats on a longitudinal gradient of increasing rainfall extending from southeastern California, through southern Arizona, and into southwestern New Mexico. Local communities of harvester ants...Ants; Arizona; California; Communities; Competition; Desert Granivores; Diversity; Insects; New Mexico; Novomessor; Pheidole; Pogonomyrmex; Resource allocation; Veromessor.1977
28 Capecchi, Mario R.Isolation of a suppressible nonsense mutant in mammalian cellsAn HGPRT- cell line derived from mouse L cells has been shown to have the following properties: it is CRM'; the defective HGPRT molecules are altered in the carboxyterminal peptide; the mutant cells regain HGPRT activity when ochre-suppressor tRNA is microinjected into them, but not when amber...HGPRT cell line; HGPRT activity; Ochre nonsense mutation; Mouse L cells; Mammalian cells1977
29 Gesteland, Raymond F.Cell-free synthesis of herpes simplex virus proteinsPolyribosomes isolated from herpes simplex virus type I (HSV-1)-infected cells have been used to program a eucaryotic cell-free translation system. At least 10 HSV-specific polypeptides, with apparent molecular weights of 25,000 to 160,000, are synthesized by wild-type HSV-infected polyribosomes. Po...Viral Proteins; Herpes Simplex; Peptide Biosynthesis; Thymidine Kinase1977
30 Seger, JonNumerical method for estimating coefficients of relationship in a langur troopThe average coefficient of relationship ( r ij) among the members of a social group is expected to influence the evolution of any trait that affects the average fitness of group members other than the bearer of the trait. It is usually impossible to write a general expression for r ij , because it...Mating; Reproduction; Trait1977
31 Davidson, Diane W.Foraging ecology and community organization in desert seed-eating antsGranivorous ants in the southwestern deserts of the United States are characterized by species-specific colony foraging behaviors that determine their efficiencies at utilizing seeds from different density distributions. Workers search for food either in groups or as individuals, and these feedin...Ants; Arizona; California; Coexistence; Communities; Density specialization; Desert granivores; Foraging strategies; Insects; New Mexico; Resource partitioning1977
32 Davidson, Diane W.Size variability in the worker caste of a social insect (veromessor pergandei mayr) as a function of the competitive environmentWorker size polymorphism in colonies of Veromessor pergandei, a granivorous desert ant, is inversely related to the intensity of interspecific competition in the habitat for seven ant communities in the deserts of southern California and southern Arizona. Seed size preferences are positively corr...Ants; Arizona; California; Coexistence; Communities; Density specialization; Desert granivores; Foraging strategies; Resource partitioning; Size1978
33 Potts, Wayne K.Gong method for capturing shorebirds and other ground-roosting speciesIn many shorebird studies it is necessary to capture adult birds. While shorebirds can often be trapped on the nest, capturing them away from the nest is usually very difficult and may require expensive equipment. After weeks of failure in our attempts to capture migrant and resident shorebirds in n...Gong method; Shorebirds; Capture; Ground-roosting1979
34 Davidson, Diane W.Competition and the structure of granivore communitiesWe trace the development of our investigations of granivory in desert ecosystems, illustrating the synthesis of the comparative and experimental approaches and noting the essential contributions of both. In the process, we also call attention to several major difficulties inherent to experimentatio...Granivory; Competition; Desert Ecosystems; Competitive investigations; Experimental investigations1980
35 Davidson, Diane W.Some consequences of diffuse competition in a desert ant communityExploitative and interference competition are investigated in detail in a community of six coexisting species of granivorous desert ants . A linear model that includes both direct and indirect competitive interactions is used to predict positive or negative correlations in the abundances of com...Ants; Arizona; California; Coexistence; Communities; Density specialization; Desert granivores; Resource partitioning1980
36 Capecchi, Mario R.High efficiency transformation by direct microinjection of DNA into cultured mammalian cells.Direct microinjection of DNA by glass micropipettes was used to introduce the Herpes simplex virus thymidine kinase gene into cultured mammalian cells. When DNA was delivered directly into the nuclei of LMTK-, a mouse cell line deficient in thymidine kinase activity, 50--100% of the cells expressed ...Cell Nucleus; Cytoplasm; DNA, Viral; Microinjections; Recombination, Genetic1980-11-22
37 Olivera, Baldomero M.; Hillyard, David R.Pyridine nucleotide cycle: studies in Escherichia coli and the human cell line D98/AH2Different metabolic steps comprise the pyridine nucleotide cycles in Escherichia coli and in the human cell line HeLa D98/AH2. An analysis of the "P-labeling patterns in vivo reveals that in E. coli, pyrophosphate bond cleavage of intracellular NAD predominates, while in the human cell line, cleava...Nicotinic acid; Turnover cycle; DNA ligation; Nicotinamide1981
38 Potts, Wayne K.Emigration behavior of Clark's NutcrackerEruptive movements of the Clark's Nutcracker (Nucifraga columbiana) were observed during the late summer and fall of 1977, 1978 and 1979 in northern Utah and adjacent states. Over 2,000 emigrating nutcrackers were seen during these periods. Eruptions began in mid to late August, about the time nutcr...Breeding range; Flocks; Observations1981
39 Olivera, Baldomero M.; Gray, William RobertPeptide toxins from Conus geographus venomThe biochemical characterization of three highly toxic peptides from the venom of the marine snail Conus geographus is described in this report. These peptides cause their potent activity by inhibition of the postsynaptic terminus of the vertebrate neuromuscular junction. The relatively small size o...Conus geographus; Venom; Conotoxins; Neurotoxins1981
40 Parkinson, John StansfieldGenetics of bacterial chemotaxisMany types of motile bacteria are capable of detecting and responding to changes in their environment. Phototactic, chemotactic and thermotactic movements in bacteria are similar to more complex behaviours seen in higher organisms, and constitute useful model systems for investigating the molecular ...Bacterial chemotaxis1981
41 Coley, Phyllis D.Rates of herbivory on different tropical treesRates of herbivory on marked young and mature leaves from saplings of 21 canopy tree species were measured in the wet and dry seasons. Species were classified into two life history groups: persistent species which are found throughout the shaded understory, and pioneer species which only become e...Herbivory; Grazing damage; Tropical trees; Pioneer species; Trees -- Tropics1982
42 Sperry, John S.Anatomy of the palm Rhapis excelsa, VIII. Vessel network and vessel-length distribution in the stemTHE CONCEPT of the vessel, a conducting unit consisting of a series of vessel elements lined up end to end, has been known for well over a century (e.g., Hartig, 1878). The fact that vessels are of limited length is of considerable functional importance. If a vessel is damaged (for example, by an in...Palm stems; Palm stem anatomy; Vessel network; Vessel-length distribution; Primary vascular stem tissue; Hydraulic architechture; Water column1982
43 Olivera, Baldomero M.Poly (ADP-ribosylation) in Vitro: reaction parameters and enzyme mechanismThe reaction catalyzed by poly(ADP-ribose) synthetase from bovine thymus was investigated using the purified enzyme, calf thymus DNA, and histone H1. The rate and extent of poly(ADP-ribosylation), as well as the spectrum of acceptor proteins, changed as reaction conditions were varied. The ionic co...ADP-ribosylation; Poly(ADP-ribose) synthetase; Histone H11982
44 Sperry, John S.Observations of reaction fibers in leaves of dicotyledonsHALLE, OLDEMAN, AND TOMLINSON (1978) have discussed the transference of function between compound leaves and plagiotropic branches in the context of tree architecture. In trees conforming to Cook's model (see Halle, Oldeman, & Tomlinson, 1978), plagiotropic branches resemble compound leaves in their...Reaction fibers; Compound leaves1982
45 Bastiani, MichaelPathfinding by growth cones in the central nervous system of the grasshopper embryoIn the grasshopper embryo the morphological development of individually identified neurons can be traced prior to the onset of axonogenesis on through maturity (eg., Goodman and Spitzer, 1979). The behavior of individual growth cones can be characterized in their natural environment as they extend t...1982-06-03
46 Capecchi, Mario R.Patterns of integration of DNA microinjected into cultured mammalian cells: evidence for homologous recombination between injected plasmid DNA molecules.We examined the fate of DNA microinjected into nuclei of cultured mammalian cells. The sequence composition and the physical form of the vector carrying the selectable gene affected the efficiency of DNA-mediated transformation. Introduction of sequences near the simian virus 40 origin of DNA replic...Base Sequence; Cell Line; Genes, Viral; Genetic Vectors; Mice; Microinjections1982-11
47 Capecchi, Mario R.Establishment of mammalian cell lines containing multiple nonsense mutations and functional suppressor tRNA genes.We describe the generation of mammalian cell lines carrying amber suppressor genes. Nonsense mutants in the herpes simplex virus thymidine kinase (HSV tk) gene, the Escherichia coli xanthine-guanine phosphoribosyl transferase (Eco-gpt) gene and the aminoglycoside 3' phosphotransferase gene of the Tn...Cercopithecus aethiops; Escherichia coli; Xenopus1982-11-30
48 Coley, Phyllis D.Herbivory and defensive characteristics of tree species in a lowland tropical forestRate of herbivory and defensive characteristics of young and mature leaves were measured for saplings of 46 canopy tree species in a lowland tropical rain forest (Barro Colorado Island, Panama). Grazing rates were determined in the field for sample periods in the early wet, late wet, and dry seasons...Fiber; Herbivory; Life history; Panama; Phenolics; Plant growth; Spatial distribution; Tannins; Temporal distribution; Treefall gaps; Tropical forest1983
49 Olivera, Baldomero M.Poly(ADP-ribosylation) of a DNA topoisomeraseA DNA topoisomerase activity, copurifying with poly(ADP-ribose) synthetase from calf thymus, >95% inhibited if extensive poly(ADP-ribosylation) is allowed to occur. The inhibited DNA topoisomerase, which has drastically different elution properties on hydroxylapatite, can be reactivated by mild alka...Nicotinic acid; ADP-ribosylation; Turnover cycle; Synthetases1983
50 Seger, JonConditional relatedness, recombination, and the chromosome numbers of insectsIf two polymorphic loci are out of phase equilibrium, a homozygote at one of these loci is more highly related to its kin, at the other locus, than is an equivalent heterozygote. As a result, selection can favor (1) phenotypic responses to relative heterozygosity, and (2) increased recombination bet...Coefficients of relatedness; Conditional relatedness1983
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