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41.
Polar liquid crystalline materials can be used in optical and electronic applications, and recent interest has turned to formation strategies that exploit the shape of polar molecules and their interactions to direct molecular alignment. For example, banana-shaped molecules align their molecular bent within smectic layers, whereas conical molecules should form polar columnar assemblies. However, the flatness of the conical molecules used until now and their ability to flip have limited the success of this approach to making polar liquid crystalline materials. Here we show that the attachment of five aromatic groups to one pentagon of a C(60) fullerene molecule yields deeply conical molecules that stack into polar columnar assemblies. The stacking is driven by attractive interactions between the spherical fullerene moiety and the hollow cone formed by the five aromatic side groups of a neighbouring molecule in the same column. This packing pattern is maintained when we extend the aromatic groups by attaching flexible aliphatic chains, which yields compounds with thermotropic and lyotropic liquid crystalline properties. In contrast, the previously reported fullerene-containing liquid crystals all exhibit thermotropic properties only, and none of them contains the fullerene moiety as a functional part of its mesogen units. Our design strategy should be applicable to other molecules and yield a range of new polar liquid crystalline materials. 相似文献
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M.Umezu J.Kawai J.Suehiro M.Arita Y.Shiraishi K.Iwasaki T.Tanaka H.Niinami 《上海大学学报(自然科学版)》2004,10(Z1):25-28
There are two different methods for coronary artery bypass grafting: end-to-side and side-to-side anastomosis. In vitro mock test, flow visualization and animal experiments were performed in parallel to compare the hemodynamic effect between two methods. Thus, bioengineers can provide practical useful information to the clinical team. 相似文献
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Résumé Un pigment naphtoquinonique extrait deMicrosporum cookei présenta une forte action découplante dans la phosphorylation oxydative des mitochondries du foie de rat. 相似文献
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Ota T Suzuki Y Nishikawa T Otsuki T Sugiyama T Irie R Wakamatsu A Hayashi K Sato H Nagai K Kimura K Makita H Sekine M Obayashi M Nishi T Shibahara T Tanaka T Ishii S Yamamoto J Saito K Kawai Y Isono Y Nakamura Y Nagahari K Murakami K Yasuda T Iwayanagi T Wagatsuma M Shiratori A Sudo H Hosoiri T Kaku Y Kodaira H Kondo H Sugawara M Takahashi M Kanda K Yokoi T Furuya T Kikkawa E Omura Y Abe K Kamihara K Katsuta N Sato K Tanikawa M Yamazaki M Ninomiya K Ishibashi T Yamashita H Murakawa K Fujimori K 《Nature genetics》2004,36(1):40-45
46.
Summary Effects of atrial natriuretic factor (ANF) on monkey, rabbit and dog internal carotid arteries were investigated. ANF caused a concentration-dependent relaxation in arterial strips submaximally precontracted with noradrenaline, 5-hydroxytryptamine, or high-potassium solution (10–30 mM). The response was greatest in the monkey arteries and least in the dog arteries. These results suggest that there is a marked species difference in the ANF-induced relaxation of the internal carotid arteries. 相似文献
47.
D. G. Müller H. Kawai B. Stache E. Fölster W. Boland 《Cellular and molecular life sciences : CMLS》1990,46(5):534-536
Summary Female gametes of the marine brown algaAnalipus japonicus secrete a complex bouquet of olefinic C11-hydrocarbons. The major compound is ectocarpene, while hormosirene and dictyotene are present at levels of 2%. Although a minor constituent of the pheromone bouquet, hormosirene is 100 times more active as a male-attractant than ectocarpene. Thus, sex attraction inAnalipus is mediated by two compounds, which diverge largely in concentration and biological activity. 相似文献
48.
K. Kawai J. Hasegawa H. Shiojiri Y. Nozawa K. Tsurumi H. Fujimura 《Cellular and molecular life sciences : CMLS》1985,41(4):490-492
Summary The interaction between BW755C (3-amino-1-[m-(trifluoromethyl)phenyl]-2-pyrazoline), a potent inhibitor of both lipoxygenase and cyclo-oxygenase, and respiratory chain in mitochondria and electron transport particles (ETP) from rat livers was examined. BW755C accelerated the oxygen uptake by mitochondria without the addition of substrate for the respiratory chain. Spectrophotometric study revealed that BW755C was quickly oxidized by cytochrome oxidase in mitochondria to a compound possessing an absorption maximum at 524 nm. p-Phenylenediamine (p-diaminobenzene, PPDA), which, like BW755C, serves as an electron donor to cytoschrome oxidase, was shown to inhibit the generation of active oxygen in macrophages; the inhibition was stronger than that of BW755C. These results strongly suggest that the oxidative conversion of BW755C by mitochondrial cytochrome oxidase is associated with its potentially inhibitory action on the active oxygen-generating system in phagocytes.The authors are indebted to Dr M. Hori, Gifu College of Pharmacy and to Dr Y. Orii, Kyoto University for their kind supplies of BW755C and pure cytochrome oxidase, respectively. 相似文献
49.
Ishii KJ Kawagoe T Koyama S Matsui K Kumar H Kawai T Uematsu S Takeuchi O Takeshita F Coban C Akira S 《Nature》2008,451(7179):725-729
Successful vaccines contain not only protective antigen(s) but also an adjuvant component that triggers innate immune activation and is necessary for their optimal immunogenicity. In the case of DNA vaccines, this consists of plasmid DNA; however, the adjuvant element(s) as well as its intra- and inter-cellular innate immune signalling pathway(s) leading to the encoded antigen-specific T- and B-cell responses remain unclear. Here we demonstrate in vivo that TANK-binding kinase 1 (TBK1), a non-canonical IkappaB kinase, mediates the adjuvant effect of DNA vaccines and is essential for its immunogenicity in mice. Plasmid-DNA-activated, TBK1-dependent signalling and the resultant type-I interferon receptor-mediated signalling was required for induction of antigen-specific B and T cells, which occurred even in the absence of innate immune signalling through a well known CpG DNA sensor-Toll-like receptor 9 (TLR9) or Z-DNA binding protein 1 (ZBP1, also known as DAI, which was recently reported as a potential B-form DNA sensor). Moreover, bone-marrow-transfer experiments revealed that TBK1-mediated signalling in haematopoietic cells was critical for the induction of antigen-specific B and CD4(+) T cells, whereas in non-haematopoietic cells TBK1 was required for CD8(+) T-cell induction. These data suggest that TBK1 is a key signalling molecule for DNA-vaccine-induced immunogenicity, by differentially controlling DNA-activated innate immune signalling through haematopoietic and non-haematopoietic cells. 相似文献