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131.
Sakamoto C Yamaguchi N Yamada M Nagase H Seki M Nasu M 《Journal of microbiological methods》2007,68(3):643-647
A simplified microfluidic device for quantification of bacteria in potable water was fabricated and examined. Comparisons of counts of Escherichia coli by the microfluidic system and by epifluorescence microscopy closely correlated (r2=0.99). Bacteria in natural mineral water and in purified household tap water were accurately enumerated by using this system within 15 min after fluorescent staining. 相似文献
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Ozaki H Nakajima K Tatsui K Izumi C Kuwahara M Sawai H 《Bioorganic & medicinal chemistry letters》2003,13(15):2441-2443
The oligodeoxyribonucleotides bearing 2,2'-anhydro-beta-D-arabinofuranosyluracil derivatives were synthesized and the modified residue was converted to beta-D-arabinofuranosyluracil derivatives or beta-D-arabinofuranosylisocytosine derivatives by post-synthetic modification method. The melting profiles of their ODNs with complementary DNA were studied. 相似文献
135.
T Yamada H Ohta H Watanabe C Kanai M Tani T Ohno Y Takayama A Iwanami N Kato R Hashimoto 《PloS one》2012,7(8):e43220
Individuals with autism spectrum condition (ASC) are known to excel in some perceptual cognitive tasks, but such developed functions have been often regarded as "islets of abilities" that do not significantly contribute to broader intellectual capacities. However, recent behavioral studies have reported that individuals with ASC have advantages for performing Raven's (Standard) Progressive Matrices (RPM/RSPM), a standard neuropsychological test for general fluid intelligence, raising the possibility that ASC's cognitive strength can be utilized for more general purposes like novel problem solving. Here, the brain activity of 25 adults with high-functioning ASC and 26 matched normal controls (NC) was measured using functional magnetic resonance imaging (fMRI) to examine neural substrates of geometric reasoning during the engagement of a modified version of the RSPM test. Among the frontal and parietal brain regions involved in fluid intelligence, ASC showed larger activation in the left lateral occipitotemporal cortex (LOTC) during an analytic condition with moderate difficulty than NC. Activation in the left LOTC and ventrolateral prefrontal cortex (VLPFC) increased with task difficulty in NC, whereas such modulation of activity was absent in ASC. Furthermore, functional connectivity analysis revealed a significant reduction of activation coupling between the left inferior parietal cortex and the right anterior prefrontal cortex during both figural and analytic conditions in ASC. These results indicate altered pattern of functional specialization and integration in the neural system for geometric reasoning in ASC, which may explain its atypical cognitive pattern, including performance on the Raven's Matrices test. 相似文献
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Kunihiko Uemura Sumiyo Kanafusa Chieko Takahashi Isao Kobayashi 《Bioscience, biotechnology, and biochemistry》2017,81(4):762-767
We developed equipment that quickly and uniformly heats packed whole fish in circulating tap water using radio frequency (RF) heating. Four vacuumed plastic-packed Pacific sauries in tap water were set in a radial arrangement between coaxial cylindrical electrodes in a closed vessel. For sterilization testing, Bacillus subtilis spores added in the center of the sauries were counted after treatment. For quality assurance, meat color and backbone hardness were measured after treatment. The temperature at the center of the sauries was increased up to 130 °C for 19 min using 9 kW RF heating, and up to 119 °C for 45 min using conventional heating (CH) at 120 °C. B. subtilis spores were decreased by five logarithmic orders using RF heating and by four logarithmic orders using CH. The RF-treated meat was brighter than the CH-treated meat, and the RF-treated backbone was softer than CH-treated one. 相似文献
139.
Masanori A. Murayama Nagisa Arimitsu Jun Shimizu Naruyoshi Fujiwara Kenji Takai Yoshiki Ikeda Yoko Okada Chieko Hirotsu Erika Takada Tomoko Suzuki Noboru Suzuki 《Experimental Animals》2021,70(3):398
Alzheimer’s disease (AD) is a prevalent neurological disorder affecting memory function in elderly persons. Indeed, AD exhibits abnormality in cognitive behaviors and higher susceptibility to neuropsychiatric symptoms (NPS). Various factors including aging, sex difference and NPS severity, are implicated during in development of AD. In this study, we evaluated behavioral abnormalities of AD model, PDAPP transgenic mice at young age using the Morris Water Maze test, which was established to assess hippocampal-dependent learning and memory. We found that female AD model mice exhibited spatial learning dysfunction and highly susceptible to NPS such as anxiety and depression, whereas spatial reference memory function was comparable in female PDAPP Tg mice to female wild type (WT) mice. Spatial learning function was comparable in male AD model mice to male WT mice. Multiple regression analysis showed that spatial learning dysfunction was associated with NPS severity such as anxiety and depression. Furthermore, the analysis showed that spatial reference memory function was associated with status of depression, but not anxiety. Thus, these results suggest female dominance of spatial learning dysfunction in the AD model mice accompanying increased NPS severity. The understandings of AD model may be useful for the development of therapeutic agents and methods in human AD. 相似文献
140.
Production of Pyrroloquinoline Quinone by Using Methanol-Utilizing Bacteria 总被引:1,自引:0,他引:1 下载免费PDF全文
Teizi Urakami Kazuya Yashima Hisao Kobayashi Akio Yoshida Chieko Ito-Yoshida 《Applied microbiology》1992,58(12):3970-3976
A large number of methanol-utilizing bacteria were screened for extracellular production of pyrroloquinoline quinone (PQQ) by using methanol as the carbon and energy sources. Of the bacteria selected, Hyphomicrobium sp. strain TK 0441 was examined for PQQ production by using a jar fermentor. The amount of PQQ in the broth and the level of methanol dehydrogenase activity in the cells were increased by simply decreasing the amount of Fe added to the medium. On the other hand, extracellularly produced protein which interfered with the purification of PQQ was decreased by simply increasing the amount of Mg added to the medium. A suitable medium that contained 1 μg of Fe per ml, 150 μg of Mg per ml, and trace elements was developed. In this medium, the production of PQQ reached approximately 1 mg/ml and protein formation was low. 相似文献