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排序方式: 共有278条查询结果,搜索用时 15 毫秒
1.
Y Shinkai M Yoshimura M Morishima-Kawashima Y Ito H Shimada K Yanagisawa Y Ihara 《Canadian Metallurgical Quarterly》1997,42(6):899-908
To further investigate the process of amyloid beta-protein (Abeta) deposition, we determined, using sensitive enzyme immunoassays, the levels of Abeta40 and Abeta42 (Abetas) in the soluble and insoluble fractions of the leptomeninges (containing arachnoid mater and leptomeningeal vessels) and cerebral cortices from elderly control subjects showing various stages of Abeta deposition and from patients affected by Alzheimer's disease (AD). In both locations, insoluble Abeta levels were higher by orders of magnitude than soluble Abeta levels. Soluble Abeta levels in cortices were much lower than those in leptomeninges. In insoluble Abeta in the cortex, Abeta42 was by far the predominant species, and Abeta42 in AD cortices was characterized by the highest degree of modifications in the amino terminus. In contrast, this Abeta42 predominance was not observed in insoluble Abeta in the leptomeninges, which were found to be able to accumulate Abetas to an extent similar to that in the cortex, on a weight basis. The levels of insoluble Abeta in the leptomeninges or cortex generally correlated with the degree of cerebral amyloid angiopathy or the abundance of senile plaque, respectively. However, the presence of plaque-free cortical samples showing significant levels of insoluble Abeta42 suggests that biochemically detectable Abeta accumulation precedes immunocytochemically detectable Abeta deposition in the cortex. 相似文献
2.
Sachi Oshima Shunichi Asai Naohiko Seki Chikashi Minemura Takashi Kinoshita Yusuke Goto Naoko Kikkawa Shogo Moriya Atsushi Kasamatsu Toyoyuki Hanazawa Katsuhiro Uzawa 《International journal of molecular sciences》2021,22(12)
We identified the microRNA (miRNA) expression signature of head and neck squamous cell carcinoma (HNSCC) tissues by RNA sequencing, in which 168 miRNAs were significantly upregulated, including both strands of the miR-31 duplex (miR-31-5p and miR-31-3p). The aims of this study were to identify networks of tumor suppressor genes regulated by miR-31-5p and miR-31-3p in HNSCC cells. Our functional assays showed that inhibition of miR-31-5p and miR-31-3p attenuated cancer cell malignant phenotypes (cell proliferation, migration, and invasion), suggesting that they had oncogenic potential in HNSCC cells. Our in silico analysis revealed 146 genes regulated by miR-31 in HNSCC cells. Among these targets, the low expression of seven genes (miR-31-5p targets: CACNB2 and IL34; miR-31-3p targets: CGNL1, CNTN3, GAS7, HOPX, and PBX1) was closely associated with poor prognosis in HNSCC. According to multivariate Cox regression analyses, the expression levels of five of those genes (CACNB2: p = 0.0189; IL34: p = 0.0425; CGNL1: p = 0.0014; CNTN3: p = 0.0304; and GAS7: p = 0.0412) were independent prognostic factors in patients with HNSCC. Our miRNA signature and miRNA-based approach will provide new insights into the molecular pathogenesis of HNSCC. 相似文献
3.
Yasuji Ihara 《应用聚合物科学杂志》1988,36(4):891-897
The adsorption isotherms of sodium salts of alkyl sulfonic acid and fatty acid with various carbon numbers onto ion exchange resins were measured in the absence and in the presence of sodium chloride in aqueous solutions. In the absence of the inorganic salt, the amount of adsorption remarkably increased with an increase in the length of alkyl groups in the adsorbates. Furthermore, the amount of adsorption apparently decreased with addition of sodium chloride into the solutions and almost reached a constant value at high concentrations of NaCl. This behavior strongly suggested that the electrostatic interaction on the adsorption decreased with increasing salt concentration and that the effect of hydrophobic interaction seems to play an important role on adsorption. 相似文献
4.
Emad Shihab Akinori Ihara Yasutaka Kamei Walid M. Ibrahim Masao Ohira Bram Adams Ahmed E. Hassan Ken-ichi Matsumoto 《Empirical Software Engineering》2013,18(5):1005-1042
Bug fixing accounts for a large amount of the software maintenance resources. Generally, bugs are reported, fixed, verified and closed. However, in some cases bugs have to be re-opened. Re-opened bugs increase maintenance costs, degrade the overall user-perceived quality of the software and lead to unnecessary rework by busy practitioners. In this paper, we study and predict re-opened bugs through a case study on three large open source projects—namely Eclipse, Apache and OpenOffice. We structure our study along four dimensions: (1) the work habits dimension (e.g., the weekday on which the bug was initially closed), (2) the bug report dimension (e.g., the component in which the bug was found) (3) the bug fix dimension (e.g., the amount of time it took to perform the initial fix) and (4) the team dimension (e.g., the experience of the bug fixer). We build decision trees using the aforementioned factors that aim to predict re-opened bugs. We perform top node analysis to determine which factors are the most important indicators of whether or not a bug will be re-opened. Our study shows that the comment text and last status of the bug when it is initially closed are the most important factors related to whether or not a bug will be re-opened. Using a combination of these dimensions, we can build explainable prediction models that can achieve a precision between 52.1–78.6 % and a recall in the range of 70.5–94.1 % when predicting whether a bug will be re-opened. We find that the factors that best indicate which bugs might be re-opened vary based on the project. The comment text is the most important factor for the Eclipse and OpenOffice projects, while the last status is the most important one for Apache. These factors should be closely examined in order to reduce maintenance cost due to re-opened bugs. 相似文献
5.
Ari Hamdani Tomonori Ihara Nobuyoshi Tsuzuki Hiroshige Kikura 《Journal of Mechanical Science and Technology》2016,30(9):3897-3905
Two-phase air-water bubbly swirling flow through a pipe is a complex turbulent flow and its prediction is still challenging. The present paper describes the experimental investigation of the air-water bubbly swirling flow in vertical co-current flow. Swirling flow is induced by a twisted tape in a 20 mm inner diameter pipe. The flow is investigated using Ultrasonic velocity profiler (UVP), which allows the measurement of liquid and gas velocities simultaneously. Furthermore, simultaneous measurement of void fraction is performed using Wire mesh sensor (WMS). The experimental results reveal that swirling flow has significant impact on bubbles’ distribution. In low liquid flow rate, the average bubble velocity is fairly uniform along the radial position and void fraction increases in the near wall region. However, increasing liquid flow rate at constant gas flow rate leads to increase in void fraction in the core region, this is mainly due to drift velocity which is affected by centrifugal force. Experimental findings and parametric trends based on the effects of swirling flow are summarized and discussed. 相似文献
6.
Sho Kano Huilong Yang John McGrady Tomonori Ihara Hazuku Tatsuya Hiroaki Abe 《Journal of Nuclear Science and Technology》2019,56(3):300-309
The radiation-induced surface activation (RISA) effect will be applied to the core design in supercritical light water reactor (SCWR) in order to achieve a high performance with excellent economy and safety. The purpose of the present study is to investigate the RISA effect in the candidate fuel cladding materials in SCWR such as PNC1520. The change of weldability due to RISA effect and the related microstructure analysis were performed in oxidized PNC1520 and 304 stainless steel with various oxidization periods. The phases contained in the surface oxide layer of the present specimen were identified as Fe2CrO4, γ-Fe2O3, and Fe2O3. The lifetime of 13.8 days for wettability improving factor was confirmed in the ultraviolet (UV) irradiation. Meanwhile, the long life of 13.8 days and short life of 0.8 days for wettability improving factors were identified in the γ-ray irradiation. Based on the fact that the band gap energies of Fe2CrO4, γ-Fe2O3, and Fe2O3 were, respectively, 2.1, 2.0, and 2.2 eV, and the photo energies of UV and γ-ray irradiation were 4.48 eV and 13.3 MeV, it is therefore clarified that the hydrophilization on the oxide layer is ascribed to the RISA effect. 相似文献
7.
Soymilk coagulation process is the most important step in tofu making. An experimental setup was developed to control the coagulation temperature and heating rate by ohmic heating and to perform impedance measurement in time-sharing mode. Soymilk coagulation process was characterized by electrical impedance spectroscopy. Frequency 10 kHz was chosen to analyze the coagulation process. Normalized conductivity was useful in determination of the endpoint of soymilk coagulation process. The coagulation process was considered as two successive first-order reactions. The rate constant in the first stage was 10 times higher than that in the second stage, both rate constants increased with coagulation temperature. The activation energy in the second stage was three times greater than that in the first stage. The successive reaction process was elucidated by using soymilk coagulation mechanism. The use of impedance measurement to analyze the coagulation process provides a basis for the control of soymilk coagulation process. 相似文献
8.
T. Komatsu R. Ihara T. Honma Y. Benino R. Sato H.G. Kim T. Fujiwara 《Journal of the American Ceramic Society》2007,90(3):699-705
This paper reports recent progress in the patterning of non-linear optical crystals on the glass surface by laser irradiation. Two techniques for the writing of crystal lines have been developed, i.e., rare-earth (samarium) atom heat processing and transition metal atom heat processing, in which a continuous wave Nd:YAG laser (wavelength: λ=1064 nm) is irradiated to the glasses containing rare-earth (RE: Sm3+ , Dy3+ ) ions or transition metal (TM: Ni2+ , Fe2+ , V4+ ) ions. The writing of crystal lines such as β-BaB2 O4 , Sm x Bi1− x BO3 , and Ba2 TiGe2 O8 showing second harmonic generations has been successful. It is clarified from the azimuthal dependence of second harmonic intensity and polarized micro-Raman scattering spectra that crystal lines consist of highly oriented crystals along the crystal line growth direction. It is also possible to write two-dimensional crystal bending or curved lines by just changing the laser scanning direction. The mechanism of the laser-induced crystallization has been proposed. 相似文献
9.
Visible-light-active titanium oxide photocatalyst realized by an oxygen-deficient structure and by nitrogen doping 总被引:41,自引:0,他引:41
T. Ihara M. Miyoshi Y. Iriyama O. Matsumoto S. Sugihara 《Applied catalysis. B, Environmental》2003,42(4):403-409
A visible-light (vis)-active titanium oxide photocatalyst was prepared by a simple wet process: the calcination of the hydrolysis product of Ti(SO4)2 with ammonia using an ordinary electric furnace in dry air at 400 °C. The color of this photocatalyst was vivid yellow and absorbed light in the blue (400 nm) to bluish-green (550 nm) region exclusively. Its structure was characterized to anatase with oxygen-deficient stoichiometry by XRD and X-ray photoelectron spectroscopy. Nitrogen was also detected, but only in trace amounts. Using blue-light-emitting diodes as a light source, 540 ppm of acetone was decomposed within 36 h and a stoichiometric yield of CO2 was obtained. From the results of the crystalline size D, it was found that vis-activity could be realized on polycrystalline particles and the grain-boundaries (GBs) are thought to be important, since oxygen vacancies are easily created in GBs, which could form a GB state. Finally, we concluded that oxygen-deficient sites formed in GBs are important to emerge vis-activity, and nitrogen doped in the part of oxygen-deficient sites are important as a blocker for reoxidation. 相似文献
10.