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排序方式: 共有1758条查询结果,搜索用时 15 毫秒
61.
Goro Aoyama Kiyoshi Fujimoto Kenichi Katono Takuji Nagayoshi Atsushi Baba Kenichi Yasuda 《Journal of Nuclear Science and Technology》2016,53(4):537-545
A prototype ultrasonic liquid film sensor was applied to a high-temperature steam–water two-phase flow experiment. The liquid film sensor was vertically installed in a loop which was connected to HUSTLE, a multi-purpose steam source test facility. The hydraulic diameter of the measurement section was 9.4 mm. The output waveforms of the sensor were acquired with a digital oscilloscope. The fluid temperature and system pressure were kept at 288 °C and 7.2 MPa, respectively, during the experiment. The pulse-echo method was used to calculate the liquid film thickness. The cross-correlation calculation was utilized to determine the time difference between the pulse reflected at the sensor surface and the pulse reflected at the liquid film surface. The time-averaged liquid film thicknesses were less than 0.055 mm in the annular flow condition. The increase of the time-averaged thickness was small with the change of the gas momentum flux. The film thicknesses measured with the sensor were compared with the past experimental results; the former were smaller than one-fourth of the thickness estimated as the mean film thickness. The comparison results suggested that the continuous liquid sublayer thickness was measured with the liquid film sensor. 相似文献
62.
63.
Yu Takanashi Yuki OrikasaMasato Mogi Masatsugu OishiHaruno Murayama Kenji SatoHisao Yamashige Daiko TakamatsuTakahiro Fujimoto Hajime TanidaHajime Arai Toshiaki OhtaEiichiro Matsubara Yoshiharu UchimotoZempachi Ogumi 《Journal of power sources》2011,196(24):10679-10685
Solid electrolyte interface (SEI) films formed on Li1−xCoO2 electrodes were observed with hard X-ray photoelectron spectroscopy (HX-PES). This paper particularly focuses on film thickness estimation using HX-PES with theoretical calculation. The validity of the calculation was proven by experiments using model SEI films. The native film formed on a LiCoO2 composite electrode was estimated to be LiF with its thickness of 5 nm. Formation of Co (II) species on top of LiCoO2 was also indicated. Storage of the electrode at 60 °C brought about considerable film growth (30-40 nm) with carbonate compounds formation. SEI film changes during charging of the LiCoO2 electrode were also examined. The main component in the film was deduced to be LiF or a kind of fluorite, with its thickness decreased during charging. The SEI formation mechanisms are also elucidated. 相似文献
64.
Single‐Crystal‐Like Organic Thin‐Film Transistors Fabricated from Dinaphtho[2,3‐b:2′,3′‐f]thieno[3,2‐b]thiophene (DNTT) Precursor–Polystyrene Blends 下载免费PDF全文
65.
Discovery of a Novel Scaffold as an Indoleamine 2,3‐Dioxygenase 1 (IDO1) Inhibitor Based on the Pyrrolopiperazinone Alkaloid,Longamide B 下载免费PDF全文
Zenyu Shiokawa Emi Kashiwabara Daisuke Yoshidome Prof. Dr. Koichi Fukase Dr. Shinsuke Inuki Prof. Dr. Yukari Fujimoto 《ChemMedChem》2016,11(24):2682-2689
Indoleamine 2,3‐dioxygenase 1 (IDO1) has emerged as a key target for cancer therapy, as IDO1 plays a critical role in the capacity of tumor cells to evade the immune system. The pyrrolopiperazinone alkaloid longamide B and its derivatives were identified as novel IDO1 inhibitors based on docking studies and small library synthesis. The thioamide derivative showed higher IDO1 inhibitory activity than longamide B, and displayed an activity similar to that of a representative IDO1 inhibitor, 1‐methyl‐tryptophan. These results suggest that the pyrrolopiperazinone scaffold of longamide B could be used in the development of IDO1 inhibitors. 相似文献
66.
Kentaro Fujimoto Yoshiyasu Matsumoto Kohki Oikawa Jun-ichi Nomura Yasuyoshi Shimada Shunrou Fujiwara Kazunori Terasaki Masakazu Kobayashi Kenji Yoshida Kuniaki Ogasawara 《International journal of molecular sciences》2016,17(8)
The purpose of the present study was to determine whether cerebral hyperperfusion after revascularization inhibits development of cerebral ischemic lesions due to artery-to-artery emboli during exposure of the carotid arteries in carotid endarterectomy (CEA). In patients undergoing CEA for internal carotid artery stenosis (≥70%), cerebral blood flow (CBF) was measured using single-photon emission computed tomography (SPECT) before and immediately after CEA. Microembolic signals (MES) were identified using transcranial Doppler during carotid exposure. Diffusion-weighted magnetic resonance imaging (DWI) was performed within 24 h after surgery. Of 32 patients with a combination of reduced cerebrovascular reactivity to acetazolamide on preoperative brain perfusion SPECT and MES during carotid exposure, 14 (44%) showed cerebral hyperperfusion (defined as postoperative CBF increase ≥100% compared with preoperative values), and 16 (50%) developed DWI-characterized postoperative cerebral ischemic lesions. Postoperative cerebral hyperperfusion was significantly associated with the absence of DWI-characterized postoperative cerebral ischemic lesions (95% confidence interval, 0.001–0.179; p = 0.0009). These data suggest that cerebral hyperperfusion after revascularization inhibits development of cerebral ischemic lesions due to artery-to-artery emboli during carotid exposure in CEA, supporting the “impaired clearance of emboli” concept. Blood pressure elevation following carotid declamping would be effective when embolism not accompanied by cerebral hyperperfusion occurs during CEA. 相似文献
67.
Yasuha Watanabe Prof. Kenzo Fujimoto 《Chembiochem : a European journal of chemical biology》2020,21(22):3244-3248
The regulation of DNAzyme activity is an important problem for its in vivo applications. We achieved photochemical regulation of DNAzyme activity by using reversible DNA photo-crosslinking of 3-cyanovinylcarbazole (CNVK). The ODN containing CNVK photo-crosslinked to a pyrimidine base in the complementary strand after a few seconds of photoirradiation, and its photoadduct was split by photoirradiation of another wavelength. The activity of photo-crosslinked DNAzyme with CNVK was completely inhibited (OFF state). In contrast, after 312 nm irradiation, DNAzyme activity was recovered upon addition of a substrate strand (ON state). In addition, the photo-crosslinked DNAzyme is prone to enzymatic digestion by exonuclease. This photochemical OFF to ON switching with reversible DNA photo-crosslinking was regulated at the desired time and position; therefore, it might be possible to use it for in vivo application. 相似文献
68.
Kaname Uno Shohei Iyoshi Masato Yoshihara Kazuhisa Kitami Kazumasa Mogi Hiroki Fujimoto Mai Sugiyama Yoshihiro Koya Yoshihiko Yamakita Akihiro Nawa Tomohiro Kanayama Hiroyuki Tomita Atsushi Enomoto Hiroaki Kajiyama 《International journal of molecular sciences》2022,23(8)
Epithelial ovarian cancer (EOC) is the most lethal gynecologic malignancy and has a unique metastatic route using ascites, known as the transcoelomic root. However, studies on ascites and contained cellular components have not yet been sufficiently clarified. In this review, we focus on the significance of accumulating ascites, contained EOC cells in the form of spheroids, and interaction with non-malignant host cells. To become resistant against anoikis, EOC cells form spheroids in ascites, where epithelial-to-mesenchymal transition stimulated by transforming growth factor-β can be a key pathway. As spheroids form, EOC cells are also gaining the ability to attach and invade the peritoneum to induce intraperitoneal metastasis, as well as resistance to conventional chemotherapy. Recently, accumulating evidence suggests that EOC spheroids in ascites are composed of not only cancer cells, but also non-malignant cells existing with higher abundance than EOC cells in ascites, including macrophages, mesothelial cells, and lymphocytes. Moreover, hetero-cellular spheroids are demonstrated to form more aggregated spheroids and have higher adhesion ability for the mesothelial layer. To improve the poor prognosis, we need to elucidate the mechanisms of spheroid formation and interactions with non-malignant cells in ascites that are a unique tumor microenvironment for EOC. 相似文献
69.
Metabolic Activation of Heterocyclic Amines and Expression of Xenobiotic‐Metabolizing Enzymes in the Gastrointestinal Tract of Rats 下载免费PDF全文
Wageh S. Darwish Shouta M. M. Nakayama Yuumi Itotani Marumi Ohno Yoshinori Ikenaka Mayumi Ishizuka 《Journal of food science》2015,80(7):T1627-T1632
Heterocyclic amines get entry into human body mainly through ingestion of pan‐fried meats cooked at high temperatures. Exposure of the gastrointestinal tract (GIT) to ingested xenobiotics prior to delivery to the liver may lead to metabolic activation, which may explain the high incidence of GIT carcinogenesis. Therefore, this study investigated the mutagenic activation of 2 heterocyclic amines, 2‐aminoanthracene (2‐AA) and 3‐amino‐1‐methyl‐5H‐prydo[4,3‐b]indole (Trp‐P‐2), in the GIT of rats. In addition, the constitutive mRNA expression profiles of xenobiotic‐metabolizing enzymes (XMEs) in the GIT of rats were examined. Metabolic activation of 2‐AA was detected in all GIT tissues except the duodenum and rectum, and it was detected at high levels in the ileum and cecum. Furthermore, we revealed high metabolic activation of 2‐AA and Trp‐P‐2 in the jejunum. The mRNA expression of phase I and II enzymes in rat GIT corresponded with their mutagenic activation ability. In conclusion, our results suggest that different expression levels of XME among GIT tissues may contribute to the tissue‐specific differences in metabolic activation of xenobiotics such as heterocyclic amines in rats. 相似文献
70.
The methanolic extract of the marine sponge Ircinia felix has yielded nine novel fatty acid esters, (7E, 12E, 18R, 20Z)-variabilin (5Z, 9Z)-22-methyltricosadienoate, (7E, 12E, 18R, 20Z)-variabilin (5Z, 9Z)-tetracosadienoate, (7E, 12E, 18R, 20Z)-variabilin hexadecanoate, (7E, 12E, 18R, 20Z)-variabilin 10-methylhexadecanoate, (7E, 12E, 18R, 20Z)-variabilin 15-methylhexadecanoate, (7E, 12E, 18R, 20Z)-variabilin 14-methylhexadecanoate, (7E, 12E, 18R, 20Z)-variabilin 9-octadecenoate, (7E, 12E, 18R, 20Z)-variabilin octadecanoate, and (7E, 12E, 18R, 20Z)-variabilin 2,11-dimethyloctadecanoate, along with the recently described (7E, 12E, 18R, 20Z)-variabilin 11-methyloctadecanoate. The characterization of the new fatty acids (5Z, 9Z)-22-methyltricosadienoic and 2,11-dimethyloctadecanoic acids is also described. The chemical structures were determined by
extensive spectroscopic, chromatographic, and chemical analyses. 相似文献