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排序方式: 共有3479条查询结果,搜索用时 31 毫秒
1.
Tsuneaki Matsudaira Masashi Wada Naoki Kawashima Miyuki Takeuchi Daisaku Yokoe Takeharu Kato Masasuke Takata Satoshi Kitaoka 《Journal of the European Ceramic Society》2021,41(5):3150-3160
Mass transfer in polycrystalline Yb2SiO5 wafers with precise composition control was evaluated and analyzed by oxygen permeation experiments at high temperatures using an oxygen tracer. Oxygen permeation proceeded due to mutual grain boundary diffusion of oxide ions and Yb ions without synergistic effects such as acceleration or suppression. The oxygen shielding properties of Yb2SiO5 were compared with those of the other line compounds such as Yb2Si2O7 and Al2O3 based on the determined mass transfer parameters. It was found that the more preferentially an oxide ion diffuses in the grain boundary compared to the interior of the grain, the greater the effect of suppressing the movement of the oxide ion by applying an oxygen potential gradient becomes. 相似文献
2.
Dr. Shingo Naraki Mai Kakihara Sayuri Kato Dr. Yusuke Saga Dr. Kazuto Mannen Dr. Shohei Takase Dr. Akihito Takano Sayaka Shinpo Dr. Tsutomu Hosouchi Dr. Takahisa Nakane Dr. Hideyuki Suzuki Dr. Tetsuo Kushiro 《Chembiochem : a European journal of chemical biology》2021,22(11):1992-2001
Imperata cylindrica is known to produce a pair of triterpenes, isoarborinol and fernenol, that exhibit identical planar structures but possess opposite stereochemistry at six of the nine chiral centers. These differences arise from a boat or a chair cyclization of the B-ring of the substrate. Herein, we report the characterization of three OSC genes from I. cylindrica. IcOSC1 and IcOSC5 were identified as isoarborinol and fernenol synthases, respectively, while IcOSC3 was characterized as a multifunctional enzyme that produces glutinol and friedelin as its major products. Mutational studies of isoarborinol and fernenol synthases revealed that the residues surrounding the DCTAE motif partially affected the conformation of the B-ring during cyclization. Additionally, the IcOSC1-W255H mutant produced the rare triterpene boehmerol. The introduced histidine residue presumably abstracted a proton from the intermediary carbocation at C18 during the 1,2-rearrangement. Expression analysis indicated that all OSC genes were highly expressed in stems. 相似文献
3.
Noritaka Yonezawa Hideki Murakami Satoru Demura Satoshi Kato Shinji Miwa Katsuhito Yoshioka Kazuya Shinmura Noriaki Yokogawa Takaki Shimizu Norihiro Oku Ryo Kitagawa Makoto Handa Ryohei Annen Yuki Kurokawa Kazumi Fushimi Eishiro Mizukoshi Hiroyuki Tsuchiya 《International journal of molecular sciences》2021,22(4)
We evaluated the abscopal effect of re-implantation of liquid nitrogen-treated tumor-bearing bone grafts and the synergistic effect of anti-PD-1 (programmed death-1) therapy using a bone metastasis model, created by injecting MMT-060562 cells into the bilateral tibiae of 6–8-week-old female C3H mice. After 2 weeks, the lateral tumors were treated by excision, cryotreatment using liquid nitrogen, excision with anti-PD-1 treatment, and cryotreatment with anti-PD-1 treatment. Anti-mouse PD-1 4H2 was injected on days 1, 6, 12, and 18 post-treatment. The mice were euthanized after 3 weeks; the abscopal effect was evaluated by focusing on growth inhibition of the abscopal tumor. The re-implantation of frozen autografts significantly inhibited the growth of the remaining abscopal tumors. However, a more potent abscopal effect was observed in the anti-PD-1 antibody group. The number of CD8+ T cells infiltrating the abscopal tumor and tumor-specific interferon-γ (IFN-γ)-producing spleen cells increased in the liquid nitrogen-treated group compared with those in the excision group, with no significant difference. The number was significantly higher in the anti-PD-1 antibody-treated group than in the non-treated group. Overall, re-implantation of tumor-bearing frozen autograft has an abscopal effect on abscopal tumor growth, although re-implantation of liquid nitrogen-treated bone grafts did not induce a strong T-cell response or tumor-suppressive effect. 相似文献
4.
Ilham M. Alshiraihi Dillon K. Jarrell Zeyad Arhouma Kelly N. Hassell Jaelyn Montgomery Alyssa Padilla Hend M. Ibrahim Debbie C. Crans Takamitsu A. Kato Mark A. Brown 《International journal of molecular sciences》2020,21(24)
SMYD3 is a lysine methyltransferase that regulates the expression of over 80 genes and is required for the uncontrolled proliferation of most breast, colorectal, and hepatocellular carcinomas. The elimination of SMYD3 restores normal expression patterns of these genes and halts aberrant cell proliferation, making it a promising target for small molecule inhibition. In this study, we sought to establish a proof of concept for our in silico/in vitro hit-to-lead enzyme inhibitor development platform and to identify a lead small molecule candidate for SMYD3 inhibition. We used Schrodinger® software to screen libraries of small molecules in silico and the five compounds with the greatest predicted binding affinity within the SMYD3 binding pocket were purchased and assessed in vitro in direct binding assays and in breast cancer cell lines. We have confirmed the ability of one of these inhibitors, Inhibitor-4, to restore normal rates of cell proliferation, arrest the cell cycle, and induce apoptosis in breast cancer cells without affecting wildtype cell behavior. Our results provide a proof of concept for this fast and affordable small molecule hit-to-lead methodology as well as a promising candidate small molecule SMYD3 inhibitor for the treatment of human cancer. 相似文献
5.
Circular data are those for which the natural support is the unit circle and its toroidal extensions. Numerous constructions have been proposed which can be used to generate models for such data. We propose a new, very general, one based on the normalization of the spectra of complex-valued stationary processes. As illustrations of the new construction's application, we study models for univariate circular data obtained from the spectra of autoregressive moving average models and relate them to existing models in the literature. We also propose and investigate multivariate circular models obtained from the high-order spectra of stationary stochastic processes generated using linear filtering with an autoregressive moving average response function. A new family of distributions for a Markov process on the circle is also introduced. Results for asymptotically optimal inference for dependent observations on the circle are presented which provide a new paradigm for inference with circular models. The application of one of the new families of spectra-generated models is illustrated in an analysis of wind direction data. 相似文献
6.
Applicability of vacuum‐microwave drying for tomato fruit based on evaluations of energy cost,color, functional components,and sensory qualities 下载免费PDF全文
7.
8.
Koji Kamagata Christina Andica Ayumi Kato Yuya Saito Wataru Uchida Taku Hatano Matthew Lukies Takashi Ogawa Haruka Takeshige-Amano Toshiaki Akashi Akifumi Hagiwara Shohei Fujita Shigeki Aoki 《International journal of molecular sciences》2021,22(10)
There has been an increasing prevalence of neurodegenerative diseases with the rapid increase in aging societies worldwide. Biomarkers that can be used to detect pathological changes before the development of severe neuronal loss and consequently facilitate early intervention with disease-modifying therapeutic modalities are therefore urgently needed. Diffusion magnetic resonance imaging (MRI) is a promising tool that can be used to infer microstructural characteristics of the brain, such as microstructural integrity and complexity, as well as axonal density, order, and myelination, through the utilization of water molecules that are diffused within the tissue, with displacement at the micron scale. Diffusion tensor imaging is the most commonly used diffusion MRI technique to assess the pathophysiology of neurodegenerative diseases. However, diffusion tensor imaging has several limitations, and new technologies, including neurite orientation dispersion and density imaging, diffusion kurtosis imaging, and free-water imaging, have been recently developed as approaches to overcome these constraints. This review provides an overview of these technologies and their potential as biomarkers for the early diagnosis and disease progression of major neurodegenerative diseases. 相似文献
9.
Yuta Nishiyama Kimiko Kato Keisuke Kawasaki Masaki Nagasawa Isao Hasegawa 《Artificial Life and Robotics》2014,19(2):181-185
In this paper, we propose that the human brain develops a system to cover OTHER. This capital “OTHER” represents the transcendental other in infancy and the latent other later in life. The system grows to cover the transcendental other through the developmental process of objective–subjective distinction, and thereafter the latent other is found as a duality of the system later in life. To argue the emergence of such system regarding social conceptualization, we introduce experiments in which we verify that preschoolers abstract, categorize, and evaluate social relationships. The results show that children around 6 years old exhibit early social conceptualization and rudimentary objective–subjective distinction. Moreover, we claim that early social conceptualization is acquired through developing the heterarchical system when the experiments are regarded as communication between the participant and experimenter. Human beings may regard this heterarchical system as the self. 相似文献
10.
The pyrolysis products of lignin in open and sealed vessels were studied by pyrolysis—gas chromatography—mass spectrometry (Py-GC-MS). Several kinds of phenolic derivatives were observed in the pyrolysates in both treatments, while phenolic compounds with alkenyl or acetyl groups had higher relative contents in the open vessel than those in the sealed vessel. Phenol and its alkyl or mono-methoxy substituted derivatives become the main pyrolysis products in the sealed vessel. Most of the lignin pyrolysis products in the open vessel could be detected by Py-GC-MS, but some active products would go through further reaction in the sealed vessel. 相似文献