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51.
Wustrow DJ Maynard GD Yuan J Zhao H Mao J Guo Q Kershaw M Hammer J Brodbeck RM Near KE Zhou D Beers DS Chenard BL Krause JE Hutchison AJ 《Bioorganic & medicinal chemistry letters》2008,18(11):3376-3381
A series of 5,6-diaryl-2-amino-pyrazines were prepared and found to have antagonist-like properties at the CB1 receptor. Subsequent SAR studies optimized both receptor potency and drug-like properties including solubility and Cytochrome-P450 inhibition potential. Optimized compounds were demonstrated to be inverse agonists and compared in vivo with rimonabant for their ability to inhibit food intake, to occupy central CB1 receptors and to influence hormonal markers associated with obesity. 相似文献
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Prof Victor H. Hutchison Margaret A. Kohl 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1971,75(4):367-382
Summary Oxygen consumption was measured with an automatic continuously recording electrolysis system in toads acclimated at 15° C and under photoperiods of LD 816, 1212, 168, 66, 231 and LL and DD. All groups exposed to LD had pronounced significant daily rhythms with a trough near the onset of the photophase and a peak at the beginning of the scotophase (Figs. 1–3, 9, 10), while no rhythms were detected in animals exposed under free-running conditions of constant light (Figs. 6–7) or constant darkness (Fig. 8), even on the first day under LL or DD. These rhythms are thus shown to be non-circadian, since they do not persist in freerunning conditions of up to 45 days. Some preliminary evidence from studies on locomotor activity (Figs. 12, 13) indicates that the daily rhythm in metabolic rate may be independent of the locomotor activity cycle. The difference in the rate of oxygen consumption during peak and low hours of each daily cycle is defined as the daily routine metabolic scope, which may be more useful in ecological studies of animal energetics than the difference between the minimum and a forced maximum metabolic rate. No correlations were found between daily changes in atmospheric pressure and cycles of oxygen consumption.This work was supported by a grant from the National Science Foundation (GB-3574) and a University of Rhode Island Research Committee Grant-in-aid. We are grateful to Robert Cubert for aid in designing and constructing the electrolysis system and for assistance with computer programs. 相似文献
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J A Lautenberger M H Edgell C A Hutchison G N Godson 《Journal of molecular biology》1979,131(4):871-875
Bacteriophage G4 possesses a single EcoB site located in the overlap between restriction fragments HinfI-12 and HaeIII-6. The sequence 5′-T-G-A … 8N … T-G-C-T occurs once in this segment and nowhere else in the DNA sequence of G4. Four independent G4 mutants that were not restricted by Escherichia coli B possessed the sequence 5′-T-G-A … 8N … T-G-C-C. The common sequence shared by the previously mapped EcoB sites on φXsB1, simian virus 40, f1, and fd DNAs is 5′-T-G-A … 8N … T-G-C-T … 9N … T. However, the sequence in the region of the G4 EcoB site contains an A instead of the final T conserved in these other examples. When the G4 EcoB site is aligned with the other EcoB sites, there are no conserved residues within 50 bases of the common sequence, 5′-T-G-A … 8N … T-G-C-T, except for those seven residues. The analysis of the EcoB site on G4 provides further evidence that only those seven bases are recognized by the E. coli B restriction enzyme. 相似文献
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Enumerative and binomial sequential sampling plans for the multicolored Asian lady beetle (Coleoptera: Coccinellidae) in wine grapes 总被引:2,自引:0,他引:2
To develop a practical integrated pest management (IPM) system for the multicolored Asian lady beetle, Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae), in wine grapes, we assessed the spatial distribution of H. axyridis and developed eight sampling plans to estimate adult density or infestation level in grape clusters. We used 49 data sets collected from commercial vineyards in 2004 and 2005, in Minnesota and Wisconsin. Enumerative plans were developed using two precision levels (0.10 and 0.25); the six binomial plans reflected six unique action thresholds (3, 7, 12, 18, 22, and 31% of cluster samples infested with at least one H. axyridis). The spatial distribution of H. axyridis in wine grapes was aggregated, independent of cultivar and year, but it was more randomly distributed as mean density declined. The average sample number (ASN) for each sampling plan was determined using resampling software. For research purposes, an enumerative plan with a precision level of 0.10 (SE/X) resulted in a mean ASN of 546 clusters. For IPM applications, the enumerative plan with a precision level of 0.25 resulted in a mean ASN of 180 clusters. In contrast, the binomial plans resulted in much lower ASNs and provided high probabilities of arriving at correct "treat or no-treat" decisions, making these plans more efficient for IPM applications. For a tally threshold of one adult per cluster, the operating characteristic curves for the six action thresholds provided binomial sequential sampling plans with mean ASNs of only 19-26 clusters, and probabilities of making correct decisions between 83 and 96%. The benefits of the binomial sampling plans are discussed within the context of improving IPM programs for wine grapes. 相似文献
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Jagesh K. Tiwari Poonam D. Sarkar SK. Pandey Jai Gopal S. Raj Kumar 《Plant Cell, Tissue and Organ Culture》2010,103(2):175-187
Interspecific potato somatic hybrids between Solanum tuberosum L. (di)haploid C-13 and 1 endosperm balance number non-tuberous wild species S. etuberosum Lindl. were produced by protoplasts electrofusion. The objective was to transfer virus resistance from this wild species
into the cultivated potatoes. Post-fusion products were cultured in VKM medium followed by regeneration of calli in MS13 K medium at 20°C under a 16-h photoperiod, and regenerants were multiplied on MS medium. Twenty-one somatic hybrids were
confirmed by RAPD, SSR and cytoplasm (chloroplast/mitochondria) type analysis possessing species-specific diagnostic bands
of corresponding parents. Tetraploid nature of these somatic hybrids was determined through flow cytometry analysis. Somatic
hybrids showed intermediate phenotypes (plant, leaves and floral morphology) to their parents in glass-house grown plants.
All the somatic hybrids were male-fertile. ELISA assay of somatic hybrids after artificial inoculation of Potato virus Y (PVY)
infection reveals high PVY resistance. 相似文献