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51.
Ryuta Shigefuku Hideaki Takahashi Hiroyasu Nakano Tsunamasa Watanabe Kotaro Matsunaga Nobuyuki Matsumoto Masaki Kato Ryo Morita Yousuke Michikawa Tomohiro Tamura Tetsuya Hiraishi Nobuhiro Hattori Yohei Noguchi Kazunari Nakahara Hiroki Ikeda Toshiya Ishii Chiaki Okuse Shigeru Sase Fumio Itoh Michihiro Suzuki 《International journal of molecular sciences》2016,17(9)
The progression of chronic liver disease differs by etiology. The aim of this study was to elucidate the difference in disease progression between chronic hepatitis C (CHC) and nonalcoholic fatty liver disease (NAFLD) by means of fibrosis markers, liver function, and hepatic tissue blood flow (TBF). Xenon computed tomography (Xe-CT) was performed in 139 patients with NAFLD and 152 patients with CHC (including liver cirrhosis (LC)). The cutoff values for fibrosis markers were compared between NAFLD and CHC, and correlations between hepatic TBF and liver function tests were examined at each fibrosis stage. The cutoff values for detection of the advanced fibrosis stage were lower in NAFLD than in CHC. Although portal venous TBF (PVTBF) correlated with liver function tests, PVTBF in initial LC caused by nonalcoholic steatohepatitis (NASH-LC) was significantly lower than that in hepatitis C virus (C-LC) (p = 0.014). Conversely, the liver function tests in NASH-LC were higher than those in C-LC (p < 0.05). It is important to recognize the difference between NAFLD and CHC. We concluded that changes in hepatic blood flow occurred during the earliest stage of hepatic fibrosis in patients with NAFLD; therefore, patients with NAFLD need to be followed carefully. 相似文献
52.
Makoto Tanaka Mikio Taguchi Tsuysohi Takahama Toru Sawada Shigeru Kuroda Takao Matsuyama Shinya Tsuda Akio Takeoka Shoichi Nakano Hiroshi Hanafusa Yukinori Kuwano 《Progress in Photovoltaics: Research and Applications》1993,1(2):85-92
A new solar cell structure named HIT (Heterojunction with Intrinsic Thin layer) has been developed based on new artificially constructed junction (ACJ) technology. In this structure a non-doped a-Si thin layer was inserted between the p(a-Si)/n(c-Si) heterojunction, improving the output characteristics and achieving a conversion efficiency of 18.1%. This structure was applied to cast polycrystalline silicon solar cells of a practical size. A high conversion efficeincy of 13.6% was obtained with a cell size of 10 cm × 10 cm using various technologies, including hydrogen plasma passivation. 相似文献
53.
A. Takeoka Y. Fukuda M. Suzuki M. Hasunuma E. Sakoguchi H. Tokizaki S. Kouzuma M. Waki M. Ohnishi S. Nakano Y. Kuwano 《Progress in Photovoltaics: Research and Applications》1993,1(1):47-54
We have successfully developed and industrialized a solar-powered air conditioner that operates through a combination of photovoltaic (PV) arrays and commercial power supplies. In order to achieve the most efficient operation possible from a one-horsepower inverter-type household air conditioner, we selected a PV array output of 540 W under standard test conditions, based on single-day power use patterns for air conditioners as well as on solar cell output patterns. When using a 540-W PV array, we have shown that the system can supply at least 90% of the power consumed by an air conditioner during peak power periods in summer. We have confirmed that on average the power generated by the PV array can satisfy at least 50% of the power consumed by an air conditioner in summer. We also confirmed that the system functions according to system design specifications. There is little doubt that the introduction and widespread use of this system will play an important role in reducing peak power energy requirements in summer. 相似文献
54.
Masato Nishikuni Tsuyoshi Takahama Shingo Okamoto Kunimoto Ninomiya Hidenori Nishiwaki Shinya Tsuda Akio Takeoka Michotoshi Ohnishi Shoichi Nakano Yukinori Kuwano 《Progress in Photovoltaics: Research and Applications》1994,2(3):211-219
A new approach to high-performance a-Si solar cells was studied. a-Si films prepared at a high substrate temperature (> 250°C) have a higher absorption coefficient and a low Si H2 bond density. the effect of deposition temperature on the open-circuit voltage (Voc) has been investigated systematically for glass/SnO2 Ipin/metal and glass/metal/nip/indium tin oxide (ITO) structure a-Si solar cells. The Voc is found to depend strongly on the thermal history of the p/i interface. A short-circuit current of 19.5 mA/cm−−2 was achieved for an a-Si solar cell using an a-Si i-layer with a thickness of 4000 Å, which was prepared at a substrate temperature of 270°C. 相似文献
55.
Shoji Seki Mami Iwasaki Hiroto Makino Yasuhito Yahara Yoshitaka Miyazaki Katsuhiko Kamei Hayato Futakawa Makiko Nogami Nguyen Tran Canh Tung Tatsuro Hirokawa Mamiko Tsuji Yoshiharu Kawaguchi 《International journal of molecular sciences》2022,23(7)
Intervertebral disc (IVD) diseases are common spinal disorders that cause neck or back pain in the presence or absence of an underlying neurological disorder. IVD diseases develop on the basis of degeneration, and there are no established treatments for degeneration. IVD diseases may therefore represent a candidate for the application of regenerative medicine, potentially employing normal human dermal fibroblasts (NHDFs) induced to differentiate into nucleus pulposus (NP) cells. Here, we used a three-dimensional culture system to demonstrate that ectopic expression of MYC, KLF4, NOTO, SOX5, SOX6, and SOX9 in NHDFs generated NP-like cells, detected using Safranin-O staining. Quantitative PCR, microarray analysis, and fluorescence-activated cell sorting revealed that the induced NP cells exhibited a fully differentiated phenotype. These findings may significantly contribute to the development of effective strategies for treating IVD diseases. 相似文献
56.
57.
Noriaki Ikenaga Yoichi Kishi Zenjiro Yajima Noriyuki Sakudo Shizuka Nakano Hisato Ogiso 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2009,267(8-9):1509-1513
TiNi alloy samples implanted with various fluences of 3 MeV Cu2+ ions were characterized by transmission electron microscope (TEM) and X-ray diffractometer. Cross-sectional TEM images of the samples showed that amorphous region was seen at the fluence of 1014 ions cm?2 in case of ion implantation at 300 K of the substrate temperature, but in case of ion implantation at 100 K it did not appear even at 1015 ions cm?2. These results were also confirmed by X-ray diffraction profiles of the same samples. Consequently, the extent of microstructure change of TiNi alloy by ion implantation was different depending on the substrate temperature. 相似文献
58.
J. Yamamatsu N. Kawano T. Arashi A. Sato Y. Nakano T. Nomura 《Journal of power sources》1996,60(2):199-203
The reliability of multilayer ceramic capacitors (MLCCs) with Ni internal electrodes has been studied trom the viewpoint of partial oxygen pressure (PO2) during firing. It is shown that the load-life time of the insulation resistance (1R) was prolonged by firing under low Po2 annealing after firing, and the addition of dopants. It is also shown that the generation of oxygen vacancies led to the degradation of IR. Annealing treatment for the oxidation of the dielectric body accelerates the dielectric aging of MLCCs. It is found that the appropriate control of the PO2 during firing can improve the reliability of MLCCs with Ni electrodes to a level as high as that of MLCCs with precious metal electrodes. Thus, we have developed an MLCC with Ni electrodes that features high reliability and a large capacitance of 10 μF for the Y5V characteristic and 4.7 μF for the X7R characteristic, both in the case of the C3216 (3.2 mm × 1.6 mm × 1.4 mm) form. 相似文献
59.
Extracellular α-amylases I and II, produced by a facultative thermophile Bacillus thermoamyloliquefaciens KP 1071 capable of growing at 30–66°C, were purified to homogeneity. α-Amylase I consisted of a single polypeptide with methionine residue at the NH2-terminus. α-Amylase II consisted of two equivalent polypeptides each comprising a methionine at the NH2-terminus. α-Amylase I hydrolyzed endotypically α-1,4-bonds in glycogen, amylopectin and β-limit dextrin, but not their α-1,6-bonds. α-Amylase II degraded amylopectin and β-limit dextrin in exo-fashion by cleaving preferentially α-maltose units from the non-reducing ends and hydrolyzing their α-1,6-branch points. α-Amylase II hydrolyzed maltotriose, phenyl-α-maltoside, α- and β-cyclodextrins and pullulan, whereas α-amylase I had no activity for all these sugars. α-Amylases I and II hydrolyzed maltotetraose, maltopentaose, α-limit dextrin and amylose, but they were inactive for maltose, isomaltose and panose. It was suggested that α-amylase I is the most thermostable type of hitherto known maltotriogenic endo-acting α-amylases, and α-amylase II is the first maltogenic exo-acting α-amylase able to split α-1,6-bonds in amylopectin. 相似文献
60.
Jun Nakamura Yuusuke Maruyama Genichi Tajima Makiko Suwa Chikara Sato 《International journal of molecular sciences》2022,23(6)
The Ca2+-ATPase is an integral transmembrane Ca2+ pump of the sarcoplasmic reticulum (SR). Crystallization of the cytoplasmic surface ATPase molecules of isolated scallop SR vesicles was studied at various calcium concentrations by negative stain electron microscopy. In the absence of ATP, round SR vesicles displaying an assembly of small crystalline patches of ATPase molecules were observed at 18 µM [Ca2+]. These partly transformed into tightly elongated vesicles containing ATPase crystalline arrays at low [Ca2+] (≤1.3 µM). The arrays were classified as ‘’tetramer’’, “two-rail” (like a railroad) and ‘’monomer’’. Their crystallinity was low, and they were unstable. In the presence of ATP (5 mM) at a low [Ca2+] of ~0.002 µM, “two-rail” arrays of high crystallinity appeared more frequently in the tightly elongated vesicles and the distinct tetramer arrays disappeared. During prolonged (~2.5 h) incubation, ATP was consumed and tetramer arrays reappeared. A specific ATPase inhibitor, thapsigargin, prevented both crystal formation and vesicle elongation in the presence of ATP. Together with the second part of this study, these data suggest that the ATPase forms tetramer units and longer tetramer crystalline arrays to elongate SR vesicles, and that the arrays transform into more stable “two-rail” forms in the presence of ATP at low [Ca2+]. 相似文献