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排序方式: 共有68条查询结果,搜索用时 31 毫秒
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LoSecco JM Bionta RM Biewitt G Bratton CB Casper D Chrysicopoulou P Claus R Cortez BG Errede S Foster GW Gajewski W Ganezer KS Goldhaber M Haines TJ Jones TW Kielczewska D Kropp WR Learned JG Lehmann E Park HS Reines F Schultz J Seidel S Shumard E Sinclair D Sobel HW Stone JL Sulak L Svoboda R van der Velde JC Wuest C 《Physical review letters》1985,54(21):2299-2301
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J.C. Braekman D. Daloze R. Schubert M. Albericci B. Tursch R. Karlsson 《Tetrahedron》1978,34(10):1551-1556
The presence of terpenoids in the order Stolonifera has been established by the isolation of three novel diterpenes, 1α,4β-dihydroxyclavular-17-ene (1), 4β-hydroxyclavulara-1(15),17-diene (2) and 3α.4β-dihydroxyclavulara-1(15), 17-diene (3) from Clavularia infiata. The structure of 1 has been determined by X-ray diffraction analysis and those of 2 and 3 by chemical intercorrelation with 1. 相似文献
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John?F?StinsEmail author G?Caroline?M?van Baal Tinca?JC?Polderman Frank?C?Verhulst Dorret?I?Boomsma 《BMC neuroscience》2004,5(1):49
Background
There is great interest in appropriate phenotypes that serve as indicator of genetically transmitted frontal (dys)function, such as ADHD. Here we investigate the ability to deal with response conflict, and we ask to what extent performance variation on response interference tasks is caused by genetic variation. We tested a large sample of 12-year old monozygotic and dizygotic twins on two well-known and closely related response interference tasks; the color Stroop task and the Eriksen flanker task. Using structural equation modelling we assessed the heritability of several performance indices derived from those tasks. 相似文献8.
Sakari Leino Patrick JC May Paavo Alku Lassi A Liikkanen Hannu Tiitinen 《BMC neuroscience》2007,8(1):78
Background
In the field of auditory neuroscience, much research has focused on the neural processes underlying human sound localization. A recent magnetoencephalography (MEG) study investigated localization-related brain activity by measuring the N1m event-related response originating in the auditory cortex. It was found that the dynamic range of the right-hemispheric N1m response, defined as the mean difference in response magnitude between contralateral and ipsilateral stimulation, reflects cortical activity related to the discrimination of horizontal sound direction. Interestingly, the results also suggested that the presence of realistic spectral information within horizontally located spatial sounds resulted in a larger right-hemispheric N1m dynamic range. Spectral cues being predominant at high frequencies, the present study further investigated the issue by removing frequencies from the spatial stimuli with low-pass filtering. This resulted in a stepwise elimination of direction-specific spectral information. Interaural time and level differences were kept constant. The original, unfiltered stimuli were broadband noise signals presented from five frontal horizontal directions and binaurally recorded for eight human subjects with miniature microphones placed in each subject's ear canals. Stimuli were presented to the subjects during MEG registration and in a behavioral listening experiment. 相似文献9.
B. Tursch D. Daloze J.C. Braekman C. Hootele A. Cravador D. Losman R. Karlsson 《Tetrahedron letters》1974,15(5):409-412
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Salmoun M Braekman JC Ranarivelo Y Rasamoelisendra R Ralambomanana D Dewelle J Darro F Kiss R 《Natural product research》2007,21(2):111-120
Four calamenene sequiterpenes, (+)-(7R,10S)-15-hydroxycalamenene (3), (+)-(7R,10S)-2,15-dihydroxycalamenene (4), (+)-(7R,10S)-2-hydroxy-15-calamenal (5), (+)-(7R,10S)-15-calamenal (6), along with the amorphane sesquiterpene (+)-(1S,6R,7R,10S)-1-hydroxy-3-oxo-amorph-4-ene (16), have been isolated from the Madagascan shrub Tarenna madagascariensis (Rubiaceae) and their structures determined by spectroscopic methods and chemical correlations. Furthermore, five known related sesquiterpenes [(+)-(7R,10S)-2-hydroxycalamenene (1), (+)-(7R,10S)-3-hydroxycalamenene (2), (-)-alpha-cadinol (13), cadinenal (14), 6-epicadinenal (15)], and three known lignans [(-)-hinokinin, (-)-dihydrocubebin, (-)-cubebin] were also isolated from the same plant. This is the first report of compounds 3, 4, 5, 6, and 16 from a natural source. 相似文献