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101.
Yoko Watanabe Masaharu Nakajima Tsutomu Hoshino Koda Jayasimhulu Elwood E. Brooks Edna S. Kaneshiro 《Lipids》2001,36(5):513-519
Members of the bacterial genus Bdellovibrio include strains that are free-living whereas others are known to invade and parasitize larger Gram-negative bacteria. The
bacterium can synthesize several sphingophospholipid compounds including those with phosphoryl bonds as well as phosphonyl
bonds. In the present study, the dominant sphingophosphonolipid component was isolated by column chromatography, and the long-chain
bases, fatty acids, and polar head groups were identified by thin-layer and gas-liquid chromatographic procedures. The definitive
structural identity of the sphingolipid was established by nuclear magnetic resonance and mass spectrometry of hydrolysis
products and the intact compound. The compound was identified as N-2′-hydroxypentadecanoyl-2-amino-3,4-dihydroxyheptadecan-1-phosphono-(1-hydroxy-2-aminoethane). 相似文献
102.
Xuetao Shi Serge Ostrovidov Yihua Zhao Xiaobin Liang Motohiro Kasuya Kazue Kurihara Ken Nakajima Hojae Bae Hongkai Wu Ali Khademhosseini 《Advanced functional materials》2015,25(15):2250-2259
Engineering living tissues that simulate their natural counterparts is a dynamic area of research. Among the various models of biological tissues being developed, fiber‐shaped cellular architectures, which can be used as artificial blood vessels or muscle fibers, have drawn particular attention. However, the fabrication of continuous microfiber substrates for culturing cells is still limited to a restricted number of polymers (e.g., alginate) having easy processability but poor cell–material interaction properties. Moreover, the typical smooth surface of a synthetic fiber does not replicate the micro‐ and nanofeatures observed in vivo, which guide and regulate cell behavior. In this study, a method to fabricate photocrosslinkable cell‐responsive methacrylamide‐modified gelatin (GelMA) fibers with exquisite microstructured surfaces by using a microfluidic device is developed. These hydrogel fibers with microgrooved surfaces efficiently promote cell encapsulation and adhesion. GelMA fibers significantly promote the viability of cells encapsulated in/or grown on the fibers compared with similar grooved alginate fibers used as controls. Importantly, the grooves engraved on the GelMA fibers induce cell alignment. Furthermore, the GelMA fibers exhibit excellent processability and could be wound into various shapes. These microstructured GelMA fibers have great potential as templates for the creation of fiber‐shaped tissues or tissue microstructures. 相似文献
103.
在梳理东京都城市中心的形成以及城市规划史的基础上,通过选取两大重要的中心街区(丸之内办公街区、银座商业街区)作为案例,进一步剖析近代东京中心城区的形成,以及此后逐步迈向地域主导的规划方式的过程。其中特别着重考察在中心城区形成、发展、更新的过程中将承载了各个历史阶段记忆的街区特征(基因)传承下来并延续到未来的探索和努力。 相似文献
104.
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
105.
106.
This research demonstrated that polymerization of aniline on cellulose produces chiroptically active composites. Polymerization of aniline in the presence of cotton fibers consisting of chiral cellulose are performed to prepare a polyaniline (PANI)/cotton composite. The polymerization is conducted at the cotton interface. The resultant PANI/cotton composite shows chiroptical activity elucidated with diffuse reflectance circular dichroism. In this reaction, textile‐surface interfacial asymmetric polymerization is performed with imprinting of chiral structure from the cotton as a natural chiroptically active polymer to the PANI. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 41118. 相似文献
107.
Under the downsizing boom and cost decrease in computer-related industries, both business and individual computer users have been greatly influenced. For instance, the users will come up against the chance to handle imprecise data in real life with their computers more than ever. Therefore, solutions for easily developing fuzzy systems are strongly needed. In response to this need, many studies have been done in the fuzzy database area because fuzzy retrieval is one of the suitable ways to deal with those kind of data. In this article, the development of a fuzzy retrieval system which can be used on a personal computer is described, especially from an industrial point of view. Additionally, the effects of fuzzy retrieval are proposed and its thinkable applications are introduced. © 1996 John Wiley & Sons, Inc. 相似文献
108.
The anisotropy of continuous fiber thermoplastic composites limits the number of geometries that can be employed effectively in dynamic mechanical analysis (DMA). Therefore, a Mechanical Energy Resolver, developed for use with elastomers, was modified with a bending fixture using a cantilever beam sample geometry and a high temperature oven. The bending fixture allows determination of composite transition temperatures. Based upon the simple geometry, one can also determine elastic moduli. This test scheme can be coupled with simple shear DMA on melts to determine neat resin properties, including solidification temperature. Results are presented for several semicrystalline and armorphous thermoplastic/graphite fiber laminates and neat resins. 相似文献
109.
Atsushi Sakon Kunihiro Nakajima Sin-ya Hohara 《Journal of Nuclear Science and Technology》2019,56(2):254-259
Even a zero-power reactor core containing highly enriched uranium has a weak neutron source inherent in uranium 235, and consequently, a neutron counter placed closely to the core without external neutron source registers a certain counting rate. The study of the counting is very important for zero-power reactor physics experiments with a high precision. In this experimental study, first, at a shutdown state of the UTR-Kinki reactor without start-up neutron source, a pulse height distribution of output signals from a neutron proportional counter was measured to confirm that these signals resulted from neutron detections. At several subcritical states of the UTR, then, the Feynman-α analysis was carried out to confirm that the neutrons detected by the counter must be fission neutrons multiplied by fission chain reactions. The correlation amplitude measured in the Feynman-α analysis was much higher than that measured in a previous drive by start-up source. Further, it was also confirmed that the subcriticality dependence of neutron counting rate followed the source multiplication formula. This feature indicated that the one-point model was very successful in the subcritical range including the shutdown state. 相似文献
110.