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21.
22.
We developed equipment and methods for measuring quantitatively the local Young's modulus of solids. It consists of an electrodeless langasite oscillator and line antennas, and oscillator vibrations are generated and detected contactlessly. A constant biasing force results from oscillator mass and is independent of surface roughness. The effect of material anisotropy on the measured stiffness is theoretically discussed for studying the limitation of the quantitative measurement. The microscopy has been applied to polycrystalline copper, and the measured modulus is compared to calculations based on electron-backscatter-diffraction measurements. Also, we applied it to a duplex stainless steel and an embedded silicon-carbide fiber. The results reveal textured regions, defects with high sensitivity, and even stiffness distribution in a single grain. 相似文献
23.
M. Nakao Y. Hatamura T. Sato K. Koyano K. Ichiki H. Sangu M. Hatakeyama T. Kobata K. Nagai 《Microsystem Technologies》1995,1(3):124-128
In order to make micro 3-D structures, we are designing a table-sized factory, namely Nano Manufacturing World (NMW). In NMW, we challenged to use a new process fused by semiconductor process for preciseness and machine process for 3-dimensionality. In order to realize the new process, we designed three new mechanisms in this paper: multi-face shape making beam, co-focus rotational robot and micro mechanical tools. Through an evaluation to actually make a micro Gojunoto with the mechanisms, we confirmed their validities for functions of integration of 3-D shape construction and assembly. 相似文献
24.
The effect of small dose of topiroxostat on serum uric acid in patients receiving hemodialysis 下载免费PDF全文
Yume Nagaoka Yoshiko Tanaka Hiroshi Yoshimoto Rie Suzuki Kakei Ryu Mio Ueda Minako Akiyama Miho Nagai Yoshitaka Miyaoka Eiichiro Kanda Shinnichi Iwai Michio Nagaoka Yoshihiko Kanno 《Hemodialysis international. International Symposium on Home Hemodialysis》2018,22(3):388-393
Introduction : Topiroxostat, a recently developed xanthine oxidase inhibitor, is expected to have fewer adverse effects than allopurinol because it has different mechanism of action from alloprinol. However, its dosage, usage and safety have not been established in patients with impaired renal function or those undergoing dialysis at the development since no studies was conducted in these patients. Methods : Cross over clinical trial using 3 months of allopurinol and topiroxostat on 27 maintain Japanese HD patients were carried out. The effects on oxidative stress status of both drugs were also evaluated by measuring oxidation reduction potential. Findings : Twenty‐five of twenty‐seven patients completed study. The mean serum uric acid levels in the topiroxostat‐treated arm was significantly lower than it in the allopurinol‐treated arm time‐dependently (P < 0.0001). Corrected oxidative stress ratio defined as biological antioxidant potential/diacron reactive oxygen metabolites was significantly increased in topiroxostat‐arm (*P = 0.0035), but not in allopurinol‐arm (P = 0.1429). No significant difference was seen in diacron reactive oxygen metabolites, biological antioxidant potential, static oxidation‐reduction potential, and capacity oxidation‐reduction potential between pre and post treatment of both drugs. Discussion : It is suggested that a low dose of topiroxostat decreased serum uric acid sufficiently to maintain it below 7.0 mg/dL in patients receiving hemodialysis. 相似文献
25.
When BALB/c mice were treated with a Kampo (Japanese herbal) medicine "Sho-seiryu-to (SST)" (1 g/kg, 10 times) orally from 7 days before to 5 days after the infection and infected with mouse-adapted influenza virus A/PR/8/34 by nasal-site restricted infection, SST caused increment of the influenza virus hemagglutinin-specific IgA antibody secreting cells in nasal lymphocyte but not in Peyer's patch lymphocyte at 6 days after infection in comparison with water-treated mice. Oral administration of SST also augmented IL-2 receptor beta chain+ (activated) T-cell in Peyer's patch lymphocyte, but not in the nasal lymphocyte. We previously reported that SST showed potent anti-influenza virus activity through augmentation of the antiviral IgA antibody titer in the nasal and broncho-alveolar cavities of the mice (T. Nagai and H. Yamada, 1994, Int. J. Immunopharmacol. 16, 605-613). These results suggest that oral administration of SST shows anti-influenza virus activity in the nasal cavity by activation of T-cell in Peyer's patch lymphocyte and stimulation of production of anti-influenza virus IgA antibody in nasal lymphocyte. When ovalbumin-sensitized allergic pulmonary inflammation model mice were administered orally with SST (1 g/kg) from 8 days before (11 times) or from 2 h after (4 times) to 4 days after the infection and infected with mouse-adapted influenza virus A/PR/8/34, replications of the virus in the both nasal and broncho-alveolar cavities or only nasal cavity were significantly inhibited at 5 days after infection in comparison with water-treated control by augmenting antiviral IgA antibody, respectively. These results suggest that SST is useful for both prophylaxis and treatment of influenza virus infection on patients with allergic pulmonary inflammation, such as bronchial asthma. 相似文献
26.
AIMS AND BACKGROUND: Gliomas of the conus medullaris often show characteristic clinical, radiological, and intraoperative features which differ from gliomas involving other parts of the spinal cord. METHODS: Eight patients with histologically verified gliomas of the conus medullaris were diagnosed and studied. RESULTS: There were five men and three women ranging in age from 21 to 59 years. Predominant initial symptoms were back pain (4 cases) and leg weakness (4 cases). The most common findings on admission were flaccid paraparesis with impaired sensation and bladder dysfunction. Postoperative magnetic resonance (MR) images with more than 95% removal of a tumour were defined as "subtotal removal" (noted in 4 of 8 cases), and less than 95% as "partial removal" (4 of 8 cases). All patients had postoperative radiotherapy. During the follow-up period ranging from 3 to 10 years, there was no tumour recurrence or regrowth on MR images. CONCLUSIONS: The postoperative radiotherapy in gliomas of the conus medullaris where total resection is not possible seems provide a beneficial effect on preventing tumour regrowth. 相似文献
27.
The effect of lutein supplementation on visual fatigue: A psychophysiological analysis 总被引:1,自引:0,他引:1
Akihiro Yagi Kiyoshi Fujimoto Kazumi Michihiro Bevy Goh Daniel Tsi Hajime Nagai 《Applied ergonomics》2009,40(6):1047-1054
We used psychophysiological technology to examine the effect of an oral supplement, a combination of lutein, zeaxanthin and blackcurrant extract (LUT), on visual fatigue, within the context of a randomized, double-blind, placebo-controlled cross-over trial. The LUT supplement and placebo samples were randomly assigned to thirteen participants, who took the samples for two LUT (and vice versa) for another 2 week. Each participant completed visual proof reading tasks for 2 h during each of four testing sessions. Saccade tests were administered before and after the proof reading task, during which the participants moved their eyes back and forth between two targets positioned in the center of two checkerboards. We recorded EEG, EOG, heart rate, and facial muscle potential/performance during the saccade tests. Blood pressure was measured and subjective fatigue and stress scores were collected before and after the proof reading task. We averaged EEG starting at saccade offset in order to analyze eye fixation related potentials (EFRP). Our results suggested that the proof reading task induced visual fatigue. An analysis of EFRP and other psychophysiological data revealed significant differences between the LUT and placebo conditions. These results suggest that supplementation with LUT could help to reduce symptoms of visual fatigue. 相似文献
28.
Watanabe M Takemasa I Kawaguchi N Miyake M Nishimura N Matsubara T Matsuo E Sekimoto M Nagai K Matsuura N Monden M Nishimura O 《Proteomics. Clinical applications》2008,2(6):925-935
In the development of novel biomarkers, the proteomic approach is advantageous because using it the cancer-associated proteins can be directly identified. We previously developed a 2-nitrobenzenesulfenyl (NBS) method to improve quantitative proteome analysis. Here, we applied this method to proteomic profiling of colorectal carcinoma (CRC) to identify novel proteins with altered expression in CRC. Each pair of tumor and normal tissue specimens from 12 CRC patients was analyzed, and approximately 5000 NBS-labeled paired peaks were quantified. Peaks with altered signal intensities (>1.5-fold) and occurring frequently in the samples (>70%) were selected, and 128 proteins were identified by MS/MS analyses as differentially expressed proteins in CRC tissues. Many proteins were newly revealed to be CRC related; 30 were reported in earlier studies of CRC. Six proteins that were up-regulated in CRC (ZYX, RAN, RCN1, AHCY, LGALS1, and VIM) were further characterized and validated by Western blot and immunohistochemistry. All six were found to be CRC-localized, either in cancer cells or in stroma cells near the cancer cells. These results indicate that the proteins identified in this study are novel candidates for CRC markers, and that the NBS method is useful in proteome mining to discover novel biomarkers. 相似文献
29.
Kusaka T Ueno M Miki T Kanenishi K Nagai Y Huang CL Okamoto Y Ogawa T Onodera M Itoh S Akiguchi I Sakamoto H 《Microscopy research and technique》2007,70(7):648-655
We investigated whether beta-amyloid (Abeta)-like immunoreactivity was seen in the brains of newborn piglets. The immunoreactivity for Abeta(1-42) and Abeta(1-40) proteins, but not Abeta precursor protein, was present in CD68-positive perivascular cells of the hippocampus and in parts of the meninges. It was colocalized with immunoreactivity for receptor for advanced glycation end product and tumor necrosis factor-alpha. The protein with a molecular mass of 27 kDa, which was recognized by the Abeta antibodies, was identified as triosephosphate isomerase (TPI) with sequence homology to Abeta peptides by N-terminal amino acid sequencing, mass fingerprint analysis using matrix-associated laser desorption/ionization mass spectrometry, and Western blotting. Western blotting assay also revealed that detectable expression of Abeta proteins were not seen in the piglet brains. These findings indicate that TPI with sequence homology to Abeta peptides accumulates in perivascular cells of the microglia/macrophage lineage located around arterial vessels of the newborn piglet hippocampus. 相似文献
30.
K. Nagai 《Journal of Low Temperature Physics》1980,38(5-6):677-705
Orbital hydrodynamic equations in 3He-A are derived microscopically in the hydrodynamic regime near the transition temperature. Transport coefficients as well as reactive coefficients are evaluated as rigorously as possible. The expression for the time derivative of the phase of the order parameter is shown to contain l · rot
n
with the Yosida function as a coefficient. It is shown that when the supercurrent is given by the usual definition which includes only the first-order space derivative of the order parameter, the stress tensor becomes antisymmetric and there is an additional contribution to the local angular momentum density of dynamical origin. The stress tensor can be made symmetric by changing the definition of the supercurrent. 相似文献