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11.
Galactose and N-acetyl-D-galactosamine-inhibitable lectin of Entamoeba histolytica have roles in the pathogenicity of intestinal amoebiasis. Igl1, the intermediate subunit lectin-1 of E. histolytica, has been shown to have both hemolytic and cytotoxic activities that reside in the C-terminus of the protein. To identify the amino acid regions responsible for these activities, recombinant proteins were prepared and used in hemolytic and cytotoxic assays. The results revealed that Igl1 has multiple domains with hemolytic and cytotoxic activities and that amino acids 787-846, 968-1028 and 1029-1088 are involved in these activities. The hemolytic activities of the fragments were partly inhibited by mannose, galactose and N-acetylgalactosamine, and glucose showed lower or negligible inhibitory effects for the activities. This is the first report of a protozoan protein with hemolytic and cytotoxic activities in multiple domains. 相似文献
12.
Yi Liu Toyoki Fujiwara Hiroshi Yukawa Masahiko Morinaga 《Solar Energy Materials & Solar Cells》2000,62(1-2)
Employing the DV-Xα molecular orbital method, lithium intercalation effect and alloying effect have been investigated on the electronic structures of spinel MxMn2−xO4 and LiMxMn2−xO4 (M=Ti, V, Cr, Mn, Fe, Co, Ni and Cu). It is found that the lithium intercalation induces the electron transfer from Li to the surrounding O ions, and enlarges the Mn-3d/O-2p band gap greatly. Such a modification of the oxygen electronic state is probably related to the electrochemical cell voltage. This lithium intercalation effect still holds even in the alloyed systems. However, the amount of transferred charges from M to O ions changes depending on the alloying element, M. So the alloying addition modifies the oxygen electronic state and influences the lithium intercalation process indirectly. 相似文献
13.
The similarity between two nuclear systems is expressed by the representativity factors and maximizing its value to unity reduces the uncertainty from its existing value. As the representativity factor is a function of covariance matrix of neutron cross-sections, the inherent systematic uncertainty in neutron cross-sections inhibits it from approaching unity and hence statistical procedures have to be resorted to minimize the systematic uncertainty. As the conventional statistical techniques fail when systematic uncertainty is dominant, we propose an entropy based information theoretic approach of maximizing the mutual information by the knowledge of bounds for the correlated elements. We show that maximizing the mutual information and the representativity factors express the similar phenomena of uncertainty reduction. We estimated the bounds for the correlated elements of the correlation matrix for minor actinides and show how the systematic uncertainty is reduced when lower bound values are considered. These lower bound values aid in experimental planning for future measurement of cross-sections with reduced systematic uncertainty. 相似文献
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Hiroshi Kajioka 《Polymer》2010,51(8):1837-6705
The orientation of lamellar crystals in non-banded spherulites of it-polystyrene and it-poly(butene-1) was investigated by microbeam X-ray diffraction. The two-dimensional intensity map of diffraction enables us to examine the local orientation of lamellar crystallites in the non-banded spherulites. The obtained results indicated the re-orientation of crystallites in non-banded spherulites and confirmed our previous observation on the anisotropic birefringence of a group of crystal stacks by polarizing optical microscopy. 相似文献
16.
Yuuki Matsumoto Hiroshi Miyauchi Takashi Makino Takeshi Sugahara Kazunari Ohgaki 《Chemical engineering science》2011,(12):2672
Methane+ethane+1,1-dimethylcyclohexane+water system was investigated by using Raman spectroscopy and isothermal phase equilibrium measurements under four-phase (gas+aqueous+large guest species+hydrate phases) equilibrium conditions at 288.15 K. The results suggest that three kinds of hydrate structures emerge at 288.15 K in the methane+ethane+1,1-dimethylcyclohexane+water system. The hydrate structure for this system changed from structure-H to structure-I via structure-II with increase in the mole ratio of ethane to methane. 相似文献
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Well size-controlled copper fine particles (diameter: 100-300?nm) were used as the inner electrode material of multilayered ceramic capacitors (MLCCs). The particles were dispersed in terpineol to form a printing paste with 50?wt% copper particles. The MLCC precursor modules prepared by the layer-by-layer printing of copper and BaTiO(3) particles were cosintered. Detailed observation of the particles, paste, and MLCCs before and after sintering was carried out by electron microscopy. The sintering temperature of Cu-MLCC was as low as 960?°C. The permittivity of these MLCCs was successfully measured with the copper inner layers. 相似文献
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