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排序方式: 共有419条查询结果,搜索用时 15 毫秒
91.
Yasushi Kawakami Hisako Kojima Kazuo Nakamura Minoru Suzuki Akihiko Uchida Yoshihiko Murata Yoichi Tamai 《Lipids》1995,30(4):333-337
The occurrence of glycosphingolipids with unique carbohydrate structures in different species of cestode, Platyhelminth, which
had been shown, previously, prompted us to study the molecular species of the monohexosylceramides (cerebrosides) in the pseudophyllidean
cestode,Spirometra erinacei. The purpose of the study was to obtain a basis for future investigations of the physiological role of glycolipids in parasitism.
Cerebrosides were isolated froms. erinacei at two growth stages, i.e., from the larval form (plerocercoid) and from the adult tapeworms (intestinal form). The cerebrosides
were separated into four subfractions by silica gel column chromatography, and their constituents were analyzed by gasliquid
chromatography, gas chromatography/mass spectrometry, and high-performance liquid chromatography/mass spectrometry. The hexoses
of the cerebrosides consisted primarily of galactose in both growth stages, while only a small amount of glucose was detected.
The ceramides were composed of sphinganine (d18∶0) and phytosphingosine (t18∶0) as sphingoid bases, and of nonhydroxy fatty
acids ranging from C16 to C30 and hydroxy stearic acid (18h∶0). The cerebrosides of adult tapeworms contained more 18h∶0 than those of plerocercoids. The
combination of hexoses and ceramides in the cerebroside molecules was slightly different in the two growth stages: the glucocerebrosides
of plerocercoids contained only d18∶0-nonhydroxy fatty acids in their ceramide moieties, whereas those of adult tapeworms
contained varying ceramide moieties. Our data indicate that the molecular species of glycolipids present were essentially
homeostatic throughout growth in spite of the entirely different environmental conditions, although there were slight differences
in the hexose distribution in the two growth stages. 相似文献
92.
Shin-Yubari coal was impregnated with several catalysts of different chemical types during pulverization. The resultant system was more homogeneous and reactive than systems prepared by impregnation of coarse coal. The relative activities of the catalysts were determined as a function of gasification temperature, catalyst loading and gasifying agent. The activity sequence in steam was K ? Ba ? Ni ? Fe ? coal ash. Each catalyst had a unique reaction profile. For example, using steam the specific rate or the rate per remaining fixed-carbon weight decreased with time for the iron-catalysed reaction, whereas it increased for the potassium-catalysed reaction. A similar order of activity was observed in carbon dioxide, but a different sequence was noted for the hydrogenation reaction. Transition metal catalysts were the most active. The hydrogenation reaction profiles were different from the oxidation profiles. 相似文献
93.
Donald J. Progar Terry L. St. Clair Akihiro Yamaguchi Shoji Tamai 《The Journal of Adhesion》1995,54(1):103-114
The poly(keto-imide), LARCTM-TPI, was developed in the late 1970's and has proven to be remarkable stable as a high temperature adhesives. Thermal aging results that were generated at both NASA Langley Research Center and at Boeing Aerospace Company proved this material to be stable in adhesive bond form for at least 60,000 hours at 232°C. A commercial form of LARCTM-TPI was made available in the mid-to-late 1980's by Mitsui Toatsu Chemicals, Inc. (MTC). Since that time, MTC has optimized the process for manufacturing LARCTM-TPI with the major improvements being in molecular weight control. Most recently, MTC synthesized a derivatized version of LARCTM-TPI which contains pendant phenoxy moieties. This material is soluble in a number of organic solvents and it exhibits outstanding melt-flow properties which make it attractive as a hot-melt-processable polyimide adhesive. The synthesis and characterization of this novel material is the subject of this research paper. 相似文献
94.
Masayuki Fujimoto Hiroshi Koyama Yuji Nishi Toshimasa Suzuki Shinji Kobayashi Yukio Tamai Nobuyoshi Awaya 《Journal of the American Ceramic Society》2007,90(7):2205-2209
We characterized the structure of the crystallographic domain of a (Pr0.7 Ca0.3 )MnO3 (PCMO ( x =0.3)) thin film epitaxially grown on a (001)SrTiO3 (STO) single-crystal substrate. We found that the domain structure exhibited an atomically smooth coherent interface with the STO substrate with no misfit dislocations. The crystallographic relationships between the domains and the substrate in their planes were interpreted to be PCMO ( x =0.3)[110][001]//STO[100][010] and PCMO ( x =0.3)[001][1-10]//STO[100][010]. The domain structure of PCMO ( x =0.3)[110][1-10]//STO[100][010] has less possibility of having the larger anisotropic strain energy found in a monoclinically distorted pseudo-cubic perovskite unit cell of PCMO ( x =0.3). This epitaxial growth structure is totally different from the previously reported PCMO ( x =0.5) epitaxial thin-film structure on STO substrate. Our observations suggested that an x value change strongly influences the structure of epitaxial PCMO thin films. 相似文献
95.
Yoshinobu Nakamura Miho Yamaguchi Masayoshi Okubo 《Polymer Engineering and Science》1993,33(5):279-284
The effect of particle size on the impact properties of an epoxy resin has been studied. This resin was filled with irregular-shaped silica particles prepared by crushing fused natural raw quartz. These particles were sorted into six groups of different mean sizes ranging from 2 to 47 μm. The impact properties were measured by an instrumented Charpy type impact tested, which can record a load-displacement curve during impact fracture. The impact absorbed energy (U) was measured using specimens having a U-shaped blunt notch, and the impact fracture toughness (KCI) was measured using specimens having a sharp crack introduced by a fresh razor blade. As the particle size decreased. U increased and KCI decreased. The fractured surfaces and crack tip regions were observed using a scanning electron microscope to clarify the above phenomena. 相似文献
96.
Takuji Murata Hiroshi Tamai Takao Morinobu Mitsuhiro Manago Akira Takenaka Hiroyuki Takenaka Makoto Mino 《Lipids》1992,27(11):840-843
The β-carotene concentrations in plasma, blood cells and buccal mucosal cells were determined by high-performance liquid chromatography
with electrochemical detection. This method was 1,000 times more sensitive than the conventional spectrophotometric method.
Polymorphonuclear cells and red blood cells had lower β-carotene levels than the other cells. After oral administration of
580 mg/day of all-trans β-carotene to human male volunteers for a week, the β-carotene concentrations in all cell types increased at least several
times above the original levels. 相似文献
97.
Takahiro Yamazaki Sayuri Yamada Konomi Ohshio Miho Sugamata Yuji Morita 《International journal of molecular sciences》2022,23(3)
Lactobacillus paracasei KW3110 (KW3110) has anti-inflammatory effects, including the prevention of blue light exposure induced retinal inflammation and ageing-related chronic inflammation in mice. The mechanism involves the promotion of anti-inflammatory cytokine interleukin (IL)-10 production by KW3110, leading to reduced pro-inflammatory cytokine IL-1β production. Although various stress-induced mitochondrial damages are associated with excessive inflammatory responses, the effect of KW3110 on inflammatory-stress-induced mitochondrial damage remains unknown. In this study, we investigated the effect of KW3110 on inflammatory stress-induced mitochondrial damage using the murine macrophage-like cell line J774A.1. KW3110 treatment suppressed lipopolysaccharide (LPS)-induced mitochondrial dysfunction, including downregulation of membrane potential, induction of reactive oxygen species, and respiratory dysfunction. In addition, KW3110 prevented LPS-induced disruption of mitochondrial morphology including cristae structures. IL-10 treatment also ameliorated LPS-induced mitochondrial dysfunction and morphology disruption. These results suggest that KW3110 prevents LPS-induced mitochondrial dysfunction, potentially via promoting IL-10 production in mouse macrophages. We are the first to reveal a suppressive effect of lactic acid bacteria on mitochondrial morphology disruption in inflammatory-stressed macrophages. Our findings contribute to understanding inflammatory-stress-induced mitochondrial damage and developing food ingredients with preventive effects on mitochondrial-damage-derived inflammatory conditions. 相似文献
98.
We have fabricated graphene/graphene oxide/graphene (G/GO/G) junctions by local anodic oxidation lithography using atomic force microscopy (AFM). The conductance of the G/GO/G junction decreased with the bias voltage applied to the AFM cantilever V(tip). For G/GO/G junctions fabricated with large and small |V(tip)|. GO was semi-insulating and semiconducting, respectively. AFM-based LAO lithography can be used to locally oxidize graphene with various oxidation levels and achieve tunability from semiconducting to semi-insulating GO. 相似文献
99.
100.
Hisashi Yoshioka Akira Kamata Tatsuya Konishi Jun Takahashi Hiroshi Oda Tadakazu Tamai Haruhiko Toyohara Takuya Sugahara 《Journal of Functional Foods》2013,5(1):204-210
The anti-allergic effect of alcohol extracts from edible seaweeds was evaluated by the degranulation of a rat basophilic leukemia cell line (RBL-2H3). Extracts prepared from the brown algae Sargassum horneri, Ecklonia cava and Ecklonia kurome, inhibited the degranulation of RBL-2H3 cells, whereas those from green algae and red algae did not. The active substance in S. horneri was purified and identified as chlorophyll c2, a major pigment in brown algae. The purified chlorophyll c2 preparation also suppressed the degranulation of RBL-2H3 cells. In contrast, chlorophyll a and b did not affect cell degranulation. Therefore, chlorophyll c2 from brown algae might be useful for the prevention or mitigation of allergic symptoms. 相似文献