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排序方式: 共有59条查询结果,搜索用时 15 毫秒
1.
KEIKO TAKAHASHI HIDEKI YOKOMIZO KATSURO ISHIYAMA MASAHIKO KITSUTA MEGUMI OHASHI 《Journal of inclusion phenomena and macrocyclic chemistry》2006,56(1-2):95-99
Asymmetric reduction of indol-3-pyruvic acid (IPA) with NaBH4 in aqueous solution in the presence of various cyclodextrins (α-, β-, γ-, mono-6-amino-6-deoxy-β- and di-6ABamino-6AB-deoxy-β-cyclodextrin) was investigated. From the NMR and circular dichroism spectral studies, the conformation of the CyD–substrate complexes is suggested; the part of carboxylic group stay in the cavity of α-CyD, whole of IPA in β-CyD, two molecules in a γ-CyD cavity, and IPA(s) is/are on the rim of the cavity of mono-6-amino-6-deoxy-β- and di-6ABamino-6AB-deoxy-β-CyD (AβCyD, DAβCyD) with electrostatic interaction between amino group and carboxylic group. This conformational difference provides in the difference in the optical selectivity of reduction. 相似文献
2.
Characteristic chlorophyll (Chl) a aggregates formed in aqueous dimethyl sulfoxide (DMSO) were investigated spectroscopically. Four chlorophyll forms were found with increasing DMSO concentration; they are called A-672, A-683, A-695 and A-665 according to the wavelengths of their absorption maxima. Transformation occurred only in this order. Reverse transformation could not be realized. A-683 and A-695 were apparently formed by the interaction of Chl a with DMSO in the linear dimer and linear polymer arrangements, respectively. Coordination of the Mg atom with a DMSO O atom and interaction between the S atom of one DMSO molecule and the O atom of an other DMSO molecule should lead to formation of a sandwich-type complex of partially overlapping chlorophyll macrocycles (Chl a-DMSO)n. A-672 and A-665 were assigned to Chl a micelles and to dissolved monomeric Chl a in DMSO, respectively. Fluorescence spectra showed that the A-683 was highly fluorescent, while the A-695 was less fluorescent. Energy migration within the A-695 form to a trap with a low fluorescence yield might be responsible for this difference in the emission intensity. 相似文献
3.
Yoko M. NAKAO Takashi MIYAWAKI Shinji YASUNO Kazuhiro NAKAO Sachiko TANAKA Midori IDA Masakazu HIRATA Masato KASAHARA Kiminori HOSODA Kenji UESHIMA Kazuwa NAKAO 《Proceedings of the Japan Academy. Series B, Physical and biological sciences》2012,88(8):454-461
Objective: To investigate the significance of intra-abdominal fat area (IAFA) on new onset of individual components of the metabolic syndrome: high blood pressure, dyslipidemia, or hyperglycemia. Methods: We conducted a longitudinal study using checkup data of a hospital from 1994 to 2010. Of 25,255 subjects, we examined 1,380 Japanese, who underwent computed tomography to measure IAFA and had no metabolic syndrome components at baseline. Results: During 3.6 years of the mean follow-up period, one of metabolic syndrome components occurred in 752 subjects. Of three components, high blood pressure was more prevalent. The multiple Cox regression analysis disclosed that IAFA is significantly associated with onset of metabolic syndrome components (HR: 1.05 per 10 cm2, 95%CI: 1.03–1.07). This finding was independent of BMI, and significant even in non-obese individuals with body mass index <25 kg/m2. Conclusions: MERLOT study demonstrates that IAFA is an independent predictor for new onset of individual components of the metabolic syndrome, even in non-obese healthy Japanese. 相似文献
4.
The electronic second hyperpolarizability γ of the carbon tetrachloride molecule is calculated by the ab initio molecular orbital method considering electron correlation with large basis sets. The static electronic γ value with the CCSD(T) method is 1.65 times the Hartree-Fock value, indicating a considerable electron correlation effect. Taking account of the frequency dispersion and vibrational effects, we estimate the most probable theoretical γ value at 800 nm to be around 17900au (9.0 × 10?36 esu). On the other hand, the experimental value recently observed by optical Kerr effect method is 10.6 × 10?36 esu at 800nm. It is concluded that the major part of the experimental χ(3) value of carbon tetrachloride can account for the static electronic hyperpolarizability. 相似文献
5.
Hiromi NAKANISHI Atsushi MORI Kouki TAKEDA Houdo TANAKA Natsuko KOBAYASHI Keitaro TANOI Takashi YAMAKAWA Satoshi MORI 《Proceedings of the Japan Academy. Series B, Physical and biological sciences》2015,91(4):160-174
Six months after the explosion of TEPCO’s Fukushima Dai-ichi nuclear power plant, radioactive
silver (110mAg), was detected in concentrations of 3754 Bq/kg in Nephila
clavata (the orb-web spider; Joro-gumo in Japanese) collected at
Nimaibashi, Iitate village in Fukushima Prefecture, whereas 110mAg in the soil was
43.1 Bq/kg. A survey of 35 faunal species in the terrestrial environment during the 3.5 years
after the accident showed that most of Anthropoda had two orders higher 110mAg in
their tissues than soils, although silver is not an essential element for their life. However,
tracing of the activity of 110mAg detected in spider Atypus karschi
collected regularly at a fixed location showed that it declined much faster than the physical
half-life. These results suggest that 110mAg was at once biologically concentrated
by faunal species, especially Arthropoda, through food chain. The factors affecting the
subsequent rapid decline of 110mAg concentration in faunal species are
discussed. 相似文献
6.
7.
5-Acyl-2-furancarboxaldehydes2arelmpol-tantIntermedlateslforsynthesizingnaturallyoccuTTingfuranoldfattyacidswhichhaveantloxldanteffectsandantlneoplastlcactlvltlesInbiologicalsystems-.Nakayamaela尸reportedsuccessfulhalodesllylatlonofethyls-trlm... 相似文献
8.
KUNIMATSU NOBORU; SANO HIDEKI 《IMA Journal of Mathematical Control and Information》1998,15(4):317-330
This paper investigates the exponential stabilily of a modelof a heat exchanger of counterflow type, whose boundary conditionsare governed by boundary feedbacks. A theorem by F.L. Huangis applied to prove that the system satisfies the spectrum-determinedgrowth assumption. 相似文献
9.
Takaaki NISHIMURA Masayasu TANAKA Natsuko MORIKOSHI Tamaki YOSHIZAWA Ryo MIYACHI 《Physical Therapy Research》2021,24(3):240
Objective: To clarify the effect of intervention with dynamic motor control exercise (DMCE) for the lumbar region on low back pain in sedentary office workers (SOWs). Methods: The participants comprised 32 SOWs with low back pain who were randomly categorized into two groups: the DMCE group and the normal trunk exercise (NTE) group. Both groups performed each exercise for three days per week for 8 weeks. The primary endpoints were evaluated for the lumbar and hip flexion angles during trunk forward bending, effect of low back pain on activities of daily living (using the Oswestry Disability Index), and intensity of low back pain (using the Visual Analog Scale) pre- and post-intervention. The extent of changes was calculated by subtracting the pre-intervention value from the post-intervention value and was compared between the two groups using an unpaired t-test. Results: The extent of changes in the lumbar flexion and hip flexion angles at 10° of trunk forward bending were significantly greater in the DMCE group than in the NTE group, and no significant differences were noted between the two groups at other angles of trunk forward bending. The extent of changes in the Oswestry Disability Index and the Visual Analog Scale scores were significantly greater in the DMCE group than in the NTE group. Conclusion: DMCE is effective in improving motor control in the lumbar region and hip joints, thereby ameliorating low back pain in SOWs. 相似文献
10.
Naoki KANEKO Akinori NAKAMURA Yukihiko WASHIMI Takashi KATO Takashi SAKURAI Yutaka ARAHATA Masahiko BUNDO Akinori TAKEDA Shumpei NIIDA Kengo ITO Kenji TOBA Koichi TANAKA Katsuhiko YANAGISAWA 《Proceedings of the Japan Academy. Series B, Physical and biological sciences》2014,90(9):353-364
Alzheimer’s disease (AD) is the most common and devastating dementia. Simple and practical biomarkers for AD are urgently required for accurate diagnosis and to facilitate the development of disease-modifying interventions. The subjects for the study were selected on the basis of PiB amyloid imaging by PET. Forty PiB-positive (PiB+) individuals, including cognitively healthy controls (HC), and mild cognitive impairment and AD individuals, and 22 PiB-negative (PiB−) HC participated. Employing our novel highly sensitive immunoprecipitation-mass spectrometry, we measured plasma amyloid β-proteins (Aβs; Aβ1-40 and Aβ1-42) and Aβ-approximate peptides (AβAPs), which were cleaved from amyloid precursor protein (APP). Among the AβAPs, APP669-711 appeared to be a good reference for deciphering pathological change of Aβ1-42. We evaluated the performance of the ratio of APP669-711 to Aβ1-42 (APP669-711/Aβ1-42) as a biomarker. APP669-711/Aβ1-42 significantly increased in the PiB+ groups. The sensitivity and specificity to discriminate PiB+ individuals from PiB− individuals were 0.925 and 0.955, respectively. Our plasma biomarker precisely surrogates cerebral amyloid deposition. 相似文献