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71.
Erich Schünemann 《Planta》1930,9(4):645-672
Ohne ZusammenfassungMit 3 Textabbildungen und Tafel I. 相似文献
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Erich Ries 《Zoomorphology》1931,20(2-3):233-367
Ohne Zusammenfassung 相似文献
75.
Erich Daumann 《Planta》1931,14(3-4):777-781
Ohne ZusammenfassungMit 6 Textabbildungen. 相似文献
76.
Erich Möller 《Planta》1929,7(1):72-99
Ohne Zusammenfassung 相似文献
77.
Hara E Kubikova L Hessler NA Jarvis ED 《Proceedings. Biological sciences / The Royal Society》2009,276(1655):279-289
Social context has been shown to have a profound influence on brain activation in a wide range of vertebrate species. Best studied in songbirds, when males sing undirected song, the level of neural activity and expression of immediate early genes (IEGs) in several song nuclei is dramatically higher or lower than when they sing directed song to other birds, particularly females. This differential social context-dependent activation is independent of auditory input and is not simply dependent on the motor act of singing. These findings suggested that the critical sensory modality driving social context-dependent differences in the brain could be visual cues. Here, we tested this hypothesis by examining IEG activation in song nuclei in hemispheres to which visual input was normal or blocked. We found that covering one eye blocked visually induced IEG expression throughout both contralateral visual pathways of the brain, and reduced activation of the contralateral ventral tegmental area, a non-visual midbrain motivation-related area affected by social context. However, blocking visual input had no effect on the social context-dependent activation of the contralateral song nuclei during female-directed singing. Our findings suggest that individual sensory modalities are not direct driving forces for the social context differences in song nuclei during singing. Rather, these social context differences in brain activation appear to depend more on the general sense that another individual is present. 相似文献
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Abstract. The influence of glucose, fructose and sucrose on oviposition site selection by Lobesia botrana is studied by combining behavioural and electrophysiological experiments. Oviposition choice assays, using surrogate grapes treated with grape berry surface extracts of Vitis vinifera cv. Merlot at different development stages, show that L. botrana females are most stimulated by extracts of mature berries containing the highest concentrations of glucose and fructose. Choice assays reveal that the oviposition response to these sugars is dose-dependant (with a threshold of the applied solution = 10 m m and a maximum stimulation at 1 m ) and that females are more sensitive to fructose than to glucose. Tarsal contact-chemoreceptor sensilla are unresponsive to stimulation with sugars but the ovipositor sensilla contain at least one neurone most sensitive to fructose and sucrose with a threshold of approximately 0.5 m m . Corresponding to the behavioural data, glucose is significantly less stimulatory to sensilla than fructose or sucrose. It is argued that fructose may be of special importance for herbivorous insects exploiting fruit as an oviposition site. 相似文献
80.
Plant metabolic diversity: a regulatory perspective 总被引:3,自引:0,他引:3
Grotewold E 《Trends in plant science》2005,10(2):57-62