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排序方式: 共有2047条查询结果,搜索用时 31 毫秒
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Hideyuki Matsuura Kumiko Ohashi Hiroshi Sasako Noriko Tagawa Yuuko Takano Yumiko Ioka Kensuke Nabeta Teruhiko Yoshihara 《Plant Growth Regulation》2008,54(1):31-36
Root exudate of Vigna unguiculata was extracted from a soil system consisting of charcoal and vermiculite. Germination stimulating activity for Striga gesnerioides was found in extracts of the soil system, and an active compound was isolated. The chemical structure of the active ingredient
was determined to be (+)-4-O-acetylorobanchol, based on analysis of the spectral data of 1-D and 2-D NMR together with nuclear Overhauser effect (NOE)
experiments. Application of the active compound to the seeds of S. gesnerioides at a concentration of 0.35 × 10−9 mol/disk led to 69% germination. The germination observed with application of GR-24, a positive control, at 0.57 × 10−10 mol/disk was 80%. 相似文献
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We sequenced the 16S rRNA gene in mitochondrial DNA to characterize mithun located in Bhutan and to increase our understanding of its origin. We compared mithun with yak, European cattle, Bhutanese zebu and Indian zebu. Sequencing revealed low nucleotide diversity within the mithun population and their phylogenetic proximity to gaur. A close relationship between Bhutanese mithun and gaur was confirmed by an additional comparison with wild gaur specimens from three locations in Bhutan. Direct domestication of mithun from gaur was supported, while maternal contribution from the cattle lineage during domestication was not supported. 相似文献
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Despite increasing interest in the behavior of zoo animals, studies of nocturnal behavior of zoo animals are limited. In this study, we investigated the relationship between parturition, season, and the sleep‐related behaviors in captive reticulated giraffes to better understand the nocturnal life in giraffes. The subjects were two adult reticulated giraffes living in Kyoto City Zoo, Japan. Observations were made via an infrared camera that was mounted in the indoor enclosure between June 2007 and August 2009. We analyzed video clips that were recorded between 16:30 and 09:00 the next morning, over a total of 199 days. Sleep‐related behaviors were classified into two categories based on the posture of the giraffes; recumbent posture and paradoxical sleep. We also recorded the laterality of recumbent posture, which was coded based on the direction of the legs against the torso (right or left). Seasonal differences in sleep behaviors between summer and winter were observed in both individuals. They tended to start to lie down earlier in the winter than in the summer. Parturition also affected the behaviors as both individuals decreased the behaviors before and after the parturition of the female. Additionally, the female lay on her left side less frequently than her right when resuming a recumbent posture in the pre‐parturition period, while such laterality was not observed in the baseline and post‐parturition period. These results suggested that season and parturition are important factors for determining the sleep‐related behaviors in giraffes. Further studies are needed to understand how these changes in sleep affect other welfare parameters. 相似文献
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Hideyuki Doi Elena I. Zuykova Eisuke Kikuchi Shuichi Shikano Keiichi Kanou Natalia Yurlova Elena Yadrenkina 《Hydrobiologia》2006,571(1):395-400
We investigated spatial changes in the isotope ratios of the plankton food web in Lake Chany, Siberia, Russia, especially
at an estuarine transition zone of the lake. The δ13C values of particulate organic matter (POM) varied among the sampling sites, and increased with increasing pH of the lake
water. This may reflect a shift by phytoplankton from using CO2 to using bicarbonate for photosynthesis with increasing pH. The δ13C values of zooplankton community also changed at each site along with those of the POM. This was indicative of carbon isotope
changes of plankton food webs between the stations along an environmental gradient. 相似文献
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Binh-Nguyen Truong Koei Okazaki Hideyuki Suzuki Hitoshi Neda Toshimitsu Fukiharu Xuan-Tham Le Akira Suzuki 《Mycoscience》2006,47(2):84-90
This study was carried out to elucidate the poorly understood processes of arthroconidiation through coremium formation using
Pleurotus cystidiosus subsp. abalonus. The coremia exclusively produced dikaryotic arthroconidia with the remnant of a clamp connection. Cells in the subapical
zone of the hyphal bundle reduced their length by division before arthroconidiation. Approximately 400 000 arthroconidia were
produced by a coremium in 1 day, with constant productivity over a 2-week period. Continuous cell extension and division in
the coremium stipe supplied cells for arthroconidiation at the coremium apex, which is surrounded by a liquid droplet (coremioliquid).
Maintenance of moisture with coremioliquid was necessary for arthroconidiation. The coremioliquid formation was performed
by active liquid transportation in the hyphae, a process that was blocked by the microtubule depolymerization agent thiabendazole. 相似文献
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Hideaki Tagashira Chen Zhang Ying-mei Lu Hideyuki Hasegawa Hiroshi Kanai Feng Han Kohji Fukunaga 《Biochimica et Biophysica Acta (BBA)/General Subjects》2013