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1.
Removal of carbonyl iron-adherent/phagocytic cells from baboon peripheral blood mononuclear cells generally resulted in a depressed blastogenic response to both pokeweed mitogen and concanavalin A. In the majority of cases, no alteration in dose requirement nor shift in kinetics was apparent. Staining for peroxidase activity indicated a reduced proportion of monocytes in the population of cells treated with iron. Therefore, the results of this study strongly suggest a potentiating role for monocytes in lectin stimulation of baboon lymphocytes. 相似文献
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Oberforstmeister Wach 《Forstwissenschaftliches Centralblatt》1924,46(6):229-237
Ohne Zusammenfassung 相似文献
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Moreau C Bhérer C Vézina H Jomphe M Labuda D Excoffier L 《Science (New York, N.Y.)》2011,334(6059):1148-1150
Since their origin, human populations have colonized the whole planet, but the demographic processes governing range expansions are mostly unknown. We analyzed the genealogy of more than one million individuals resulting from a range expansion in Quebec between 1686 and 1960 and reconstructed the spatial dynamics of the expansion. We find that a majority of the present Saguenay Lac-Saint-Jean population can be traced back to ancestors having lived directly on or close to the wave front. Ancestors located on the front contributed significantly more to the current gene pool than those from the range core, likely due to a 20% larger effective fertility of women on the wave front. This fitness component is heritable on the wave front and not in the core, implying that this life-history trait evolves during range expansions. 相似文献
5.
Refojo D Schweizer M Kuehne C Ehrenberg S Thoeringer C Vogl AM Dedic N Schumacher M von Wolff G Avrabos C Touma C Engblom D Schütz G Nave KA Eder M Wotjak CT Sillaber I Holsboer F Wurst W Deussing JM 《Science (New York, N.Y.)》2011,333(6051):1903-1907
The corticotropin-releasing hormone receptor 1 (CRHR1) critically controls behavioral adaptation to stress and is causally linked to emotional disorders. Using neurochemical and genetic tools, we determined that CRHR1 is expressed in forebrain glutamatergic and γ-aminobutyric acid-containing (GABAergic) neurons as well as in midbrain dopaminergic neurons. Via specific CRHR1 deletions in glutamatergic, GABAergic, dopaminergic, and serotonergic cells, we found that the lack of CRHR1 in forebrain glutamatergic circuits reduces anxiety and impairs neurotransmission in the amygdala and hippocampus. Selective deletion of CRHR1 in midbrain dopaminergic neurons increases anxiety-like behavior and reduces dopamine release in the prefrontal cortex. These results define a bidirectional model for the role of CRHR1 in anxiety and suggest that an imbalance between CRHR1-controlled anxiogenic glutamatergic and anxiolytic dopaminergic systems might lead to emotional disorders. 相似文献
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Gustavo R. Rodríguez Javier H. Pereira da Costa Damian D. Tomat Guillermo R. Pratta Roxana Zorzoli Liliana A. Picardi 《Scientia Horticulturae》2011
The tomato fruit quality results of biochemical and physiological changes that occur during the ripening process. Although, the pericarp total protein profiles are less polymorphic than DNA-based markers the polymorphism in those could be directly associated with fruit quality traits. The aim of this work was to identify associations between polymorphic polypeptides from fruit pericarp at two ripening stages and fruit quality traits evaluated in two segregating populations of tomato. A cross between a normal ripening cultivar of Solanum lycopersicum (C, Caimanta) and a genotype carrying the nor (non ripening) gene (N) as well as a cross between Caimanta and a cherry type tomato of S. lycopersicum var. cerasiforme (Ce) showed genetic variance for several fruit quality traits such as fruit weight, shape, solids soluble content, acidity, color and fruit shelf life. The quantitative variations observed at phenotypic level had correspondence with the polymorphism detected in the protein profiles. Indeed, the polymophic polypeptides associated with quality fruit traits and fruit shelf life would be useful to assist tomato breeding programs as protein molecular markers. 相似文献
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A. Roda M. Kairo T. Damian F. Franken K. Heidweiller C. Johanns R. Mankin 《EPPO Bulletin》2011,41(2):116-121
Rhynchophorus ferrugineus, an important palm pest, was accidentally introduced into the Caribbean. A monitoring programme was established to determine the population level and distribution of infestations on Aruba and Curacao through the use of commercially available pheromone traps. Due to the small size of the islands and limited distribution of palms, eradication may be feasible using a combination of trapping, timely disposal of infested palms and curative and prophylactic chemical treatments. These studies on the pest in the Caribbean were used to help design a USDA plant health emergency response through the development of Animal Plant Health Inspection Service, Plant Protection and Quarantine New Pest Response Guidelines and provide an effective emergency response programme for other Caribbean Islands and the Americas. 相似文献
9.
Waché Y Bosser-DeRatuld A Lhuguenot JC Belin JM 《Journal of agricultural and food chemistry》2003,51(7):1984-1987
beta-Carotene is, when cleaved, an important source of flavor and aroma compounds in fruits and flowers. Among these aroma compounds, the main degradation products are beta-ionone, 5,6-epoxy-beta-ionone, and dihydroactinidiolide (DHA), which are associated by flavorists and perfumers with fruity, floral, and woody notes. These three species can be produced by degradation of beta-carotene through an attack by enzyme-generated free radicals and a cleavage at the C9-C10 bond. This study investigated the influence of cis/trans isomerism at the C9-C10 bond on the production of beta-carotene degradation compounds, first with a predictive approach and then experimentally with different isomer mixtures. beta-Carotene solutions containing high ratios of 9-cis-isomers produced more DHA, suggesting a different pathway than for the transformation of all-trans-beta-carotene to ionone and DHA. These results are important in the search for financially viable processes to produce natural carotene-derived aroma compounds. 相似文献
10.
Eshaghi S Niegowski D Kohl A Martinez Molina D Lesley SA Nordlund P 《Science (New York, N.Y.)》2006,313(5785):354-357
CorA family members are ubiquitously distributed transporters of divalent metal cations and are considered to be the primary Mg2+ transporter of Bacteria and Archaea. We have determined a 2.9 angstrom resolution structure of CorA from Thermotoga maritima that reveals a pentameric cone-shaped protein. Two potential regulatory metal binding sites are found in the N-terminal domain that bind both Mg2+ and Co2+. The structure of CorA supports an efflux system involving dehydration and rehydration of divalent metal ions potentially mediated by a ring of conserved aspartate residues at the cytoplasmic entrance and a carbonyl funnel at the periplasmic side of the pore. 相似文献