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排序方式: 共有819条查询结果,搜索用时 46 毫秒
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Seiko Miyata Sayumi Kawai Kumiko Honda Kunihiro Iwamoto Norio Ozaki 《Biological Rhythm Research》2019,50(2):171-179
Insufficient sleep and irregular sleep/wake rhythm are common problems among university students. We investigated the effect of sleep/wake rhythm and excessive daytime sleepiness (EDS) on the cortical oxygenation as measured by near-infrared spectroscopy (NIRS) and cognitive performance in university students. Peak- and integral values by a word fluency task were measured with NIRS. EDS was evaluated by the Epworth sleepiness scale (ESS), and performance function was evaluated using N-back task. Peak cerebral oxygenation was significantly correlated with ESS, bedtime, wake-up time, and median time of sleep. Accuracy on 2-back task was significantly correlated with integral value. Peak- and integral values were significantly lower, and bedtime and median time of sleep were significantly delayed in the EDS group than in the non-EDS group. EDS accompanied by delayed sleep/wake rhythm and short sleep duration may play an important role in decreasing daytime brain activity and cognitive performance. 相似文献
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Based on the base composition of nuclear DNA and DNA/DNA hybridization, Pichia galeiformis IFO 10718T was reclassified as a synonym of Pichia manshurica, and Pichia scaptomyzae IFO 1073 1T was confirmed to be a synonym of Pichia membranifaciens. Comparison of 18S rRNA gene sequences indicated that IFO 10731T (P. scaptomyzae) is identical to P. membranifaciens IFO 10215T and IFO 10725, and IFO 10718T (P. galeiformis) is identical to P. manshurica IFO 10726T. These data were consistent with the view that P scaptomyzae and P membranifaciens should be conspecific, as should P. galeiformis and P manshurica. Variation among 26S rRNA gene domain D1/D2 sequences from three P membranifaciens strains indicated that this species encompasses a genetically heterogeneous population. 相似文献
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Masai K Maruyama J Nakajima H Kitamoto K 《Bioscience, biotechnology, and biochemistry》2004,68(7):1569-1573
The distribution of the secreted protein ribonuclease T1 (RntA) fused with the enhanced green fluorescent protein (EGFP), RntA-EGFP, was visualized in hyphae of Aspergillus oryzae in the presence of a protein transport inhibitor, brefeldin A, cytochalasin A, or nocodazole. During treatment with the protein transport inhibitors, the distribution of RntA-EGFP changed and distinct patterns of fluorescence accumulation were observed. The addition of brefeldin A caused RntA-EGFP fluorescence to appear in reticular networks, and the disruption of the polymerization of actin filaments by cytochalasin A caused an increase in RntA-EGFP fluorescence intensity in the hyphae without accumulation in a specific cellular component. In contrast, RntA-EGFP fluorescence was distributed in different parts of a hypha during treatment with nocodazole, a compound that depolymerizes microtubules. In addition, quantitative analysis was performed using the RntA-EGFP visualization system to analyze the relative amount of RntA-EGFP secreted into the culture medium during treatment with the protein transport inhibitors. 相似文献
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Proliferation of donor mitochondrial DNA in nuclear transfer calves (Bos taurus) derived from cumulus cells 总被引:8,自引:0,他引:8
Takeda K Akagi S Kaneyama K Kojima T Takahashi S Imai H Yamanaka M Onishi A Hanada H 《Molecular reproduction and development》2003,64(4):429-437
In embryos derived by nuclear-transfer (NT), fusion of donor cell and recipient oocyte caused mitochondrial heteroplasmy. Previous studies from other laboratories have reported either elimination or maintenance of donor-derived mitochondrial DNA (mtDNA) from somatic cells in cloned animals. Here we examined the distribution of donor mtDNA in NT embryos and calves derived from somatic cells. Donor mitochondria were clearly observed by fluorescence labeling in the cytoplasm of NT embryos immediately after fusion; however, fluorescence diminished to undetectable levels at 24 hr after nuclear transfer. By PCR-mediated single-strand conformation polymorphism (PCR-SSCP) analysis, donor mtDNAs were not detected in the NT embryos immediately after fusion (less than 3-4%). In contrast, three of nine NT calves exhibited heteroplasmy with donor cell mtDNA populations ranging from 6 to 40%. These results provide the first evidence of a significant replicative advantage of donor mtDNAs to recipient mtDNAs during the course of embryogenesis in NT calves from somatic cells. 相似文献
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Hantavirus-specific CD8(+)-T-cell responses in newborn mice persistently infected with Hantaan virus 总被引:4,自引:0,他引:4
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Araki K Yoshimatsu K Lee BH Kariwa H Takashima I Arikawa J 《Journal of virology》2003,77(15):8408-8417
The relationship between virus-specific CD8(+)-T-cell responses and viral persistence was studied in mice by using Hantaan virus (HTNV). We first established a simple method for measuring levels of virus-specific CD8(+) T cells by flow cytometry. Next, to produce a mouse model of persistent HTNV infection, newborn mice were inoculated subcutaneously within 24 h of birth with 1 or 0.1 50% newborn mouse lethal dose of HTNV. All mice that escaped lethal infection were persistently infected with HTNV until at least 30 days after virus inoculation and had no virus-specific CD8(+) T cells producing gamma interferon (IFN-gamma). Subsequently, the virus was eliminated from some of the mice, depending on the appearance of functional virus-specific CD8(+) T cells, which have the ability to produce IFN-gamma and tumor necrosis factor alpha (TNF-alpha) and have cytotoxic activity. Neutralizing antibodies were detected in all mice, regardless of the presence or absence of virus. In the acute phase, which occurs within 30 days of infection, IFN-gamma-producing HTNV-specific CD8(+) T cells were detected on day 15 after virus inoculation. However, TNF-alpha production and the cytotoxic activity of these specific CD8(+) T cells were impaired and HTNV was not removed. Almost all of these specific CD8(+) T cells disappeared by day 18. These results suggest that functional HTNV-specific CD8(+) T cells are important for clearance of HTNV. 相似文献