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41.
E. A. Carlini M. Santos M. R. P. Sampaio 《Cellular and molecular life sciences : CMLS》1965,21(2):72-73
Zusammenfassung Anhand zweier Versuchsanordnungen wird gezeigt, dass Meskalin Histaminwirkungen verstärken kann. Ausserdem vermag es die Histamin zerstörende Wirkung der Diaminooxydase zu hemmen (in 10–5-molarer Konzentration).Es wird die Möglichkeit diskutiert, dass diese Eigenschaften mit der 4-Methoxyphenyl-äthylamin-Struktur des Meskalins in Zusammenhang stehen könnten. 相似文献
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- 《南京林业大学学报(自然科学版)》2011,35(3)
葡萄牙海岸松被松材线虫感染后的迅速死亡表明有其他生物的介入。内生细菌是一类普遍存在的生物,它在大部分植物中能形成种群。松材线虫携带的细菌也有可能导致海岸松的迅速死亡。笔者通过培养分离得到的细菌分离物,利用扩增性核糖体DNA限制性酶切片段分析(ARDRA)和变性梯度凝胶电泳分析(DGGE),了解被感染的和未被感染的海岸松内生细菌的种群结构,以分析鉴定与松材线虫相关的细菌。从样树和松材线虫中分离的细菌Alphaproteobacteria、 Bacteroidetes 属仅存在于内生菌中,而Actinobacteria、Firmicutes被发现仅与松材线虫相关。 ARDRA和 DGGE 分析证明内生菌种群结构多样性的差异可能与松材线虫的入侵有关。这种细菌种群的多样性差异似乎与Burkholderia、 Pseudomonas 和Luteibacter属中的某些菌株有关。而从树中分离出来的Janthinobacterium agaricidamnosum、 P. lutea 和 Dyella yeojuensis 与松材线虫相关 相似文献
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InSb epilayers and InSb/Al0.20In0.80Sb quantum wells were grown on Ge(001)substrates and Ge-on-insulator(GeOI)-on-Si(001)substrates by molecular beam epitaxy.Growth on both on-axis and 4°-off-axis substrate orientations was studied.Anti-phase domains were formed when InSb films were grown on on-axis substrates,but suppressed significantly by the use of 4°-off-axis substrates.Such off-axis substrates also reduced the densities of micro-twin defects and threading dislocations.The defect reduction resulted in an increase in the room-temperature electron mobility from 37,000 to 59,000 cm2/Vs in 4.0-lm-thick InSb epilayers and from 10,000 to20,000 cm2/Vs in 25-nm-thick InSb quantum wells on Ge(001)and GeOI-on-Si(001)substrates. 相似文献
46.
Tatiane Archanjo de Sales Erik Daemon Juliane Floriano Santos Lopes 《Journal of Natural History》2016,50(15-16):971-974
This study aimed to identify the feeding habit of Pheidole radoszkowskii Mayr on Rattus norvegicus (Berkenhout) carcasses, as well as whether its presence limits the occurrence of flies. Pheidole radoszkowskii exhibited more necrophagous than predatory behaviour. Its abundance was inversely proportional to that of flies, confirming that this ant species may cause lesions in carcasses and its presence limits the occurrence of flies. This work clarifies the behaviour of an ant species often encountered on carcasses. 相似文献
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J W Moura R C Stocco dos Santos M L Dagli J L D'Angelino E H Birgel W Be?ak 《Experientia》1988,44(9):785-788
Thirteen cows maintained on natural bracken fern (Pteridium aquilinum) were analyzed cytogenetically. The frequency of structural chromosome aberrations detected in peripheral blood cells was significantly higher when compared to that detected in animals raised on pasture containing no bracken fern. We discuss the clastogenic action of fern and its synergistic action with infection by type 2 and 4 papilloma virus in the same animals. 相似文献
48.
Arielson dos Santos Protázio Ralph Lacerda Albuquerque Laura Martini Falkenberg 《Journal of Natural History》2015,49(15-16):957-976
Differences in advertisement calls and calling sites are important mechanisms that regulate interactions in anuran assemblages. Individuals might have preferences for ranges of acoustic parameters and calling sites that reduce overlap and ensure coexistence. Herein, acoustic and ecological data were used to investigate the relationships among 12 anurans that co-occur in temporary ponds in the Caatinga, Cabaceiras municipality, Paraíba state, Brazil. Anurans exhibited calling activity correlated with rainfall, but were also spatially dispersed. High overlap levels in calling microhabitats and acoustic parameters were observed, especially among pairs of closely related species. Analysis of null models showed a lack of structure in the spatial and acoustic niche, indicating the lack of detected competition. Results suggest that the calling activity of the species is strongly influenced by rainfall, moreover, the temporal partition appears to ensure coexistence. Finally, strong historical effects were detected in Leiuperinae, Leptodactylidae and in the partition Hylidae–Leptodactyliformes. 相似文献
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Initial sequencing and analysis of the human genome 总被引:11,自引:0,他引:11
Lander ES Linton LM Birren B Nusbaum C Zody MC Baldwin J Devon K Dewar K Doyle M FitzHugh W Funke R Gage D Harris K Heaford A Howland J Kann L Lehoczky J LeVine R McEwan P McKernan K Meldrim J Mesirov JP Miranda C Morris W Naylor J Raymond C Rosetti M Santos R Sheridan A Sougnez C Stange-Thomann N Stojanovic N Subramanian A Wyman D Rogers J Sulston J Ainscough R Beck S Bentley D Burton J Clee C Carter N Coulson A Deadman R Deloukas P Dunham A Dunham I Durbin R French L Grafham D Gregory S 《Nature》2001,409(6822):860-921
The human genome holds an extraordinary trove of information about human development, physiology, medicine and evolution. Here we report the results of an international collaboration to produce and make freely available a draft sequence of the human genome. We also present an initial analysis of the data, describing some of the insights that can be gleaned from the sequence. 相似文献