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21.
The purpose of this present study was to investigate the distribution and expression of chymase in the lacrimal glands (LGs) of patients afflicted with IgG4-related ophthalmic disease (IgG4-ROD). LGs from patients with severe canalicular obstruction were considered the control group. Toluidine blue staining confirmed a significant increase in the number of mast cells in the LGs obtained from the IgG4-ROD patients. In addition, immunostaining of serial sections from the LGs showed a significant increase in the number of chymase-positive cells and tryptase-positive cells in the IgG4-ROD LGs compared to the normal control LGs. The mRNA expression of chymase, tryptase, TGF-β1, and collagen-I tended to increase in the IgG4-ROD LGs. Immunostaining of vimentin and α-smooth muscle actin (α-SMA) showed that myofibroblasts were the main cellular components in severely fibrotic regions of LGs in patients with IgG4-ROD. Linear regression analyses on the number of mast cells, chymase-positive cells, and tryptase-positive cells revealed significant positive correlations between those respective cells. Our findings suggest that chymase may play a role in the fibrotic disorder of IgG4-ROD LGs through the regulation of TGF-β1 activation and collagen-I deposition, and that it may be a therapeutic target for patients afflicted with IgG4-ROD.  相似文献   
22.
A 1/8-scale model was constructed of a reinforced concrete containment vessel (RCCV) used in the latest advanced boiling water reactors (ABWR). Shaking table tests were conducted on it with input motions corresponding to or exceeding a design earthquake assumed for a real Nuclear Power Plant.The objectives of the tests were to verify the structural integrity and the leak-proof functional soundness of the RCCV subjected to design earthquakes, and to determine the ultimate strength and seismic margin by an excitation that led to the model's collapse. The model, the test sequence and the pressure and leak test results were addressed in Part 1. The shaking table test method, the input motions and the test results, including the transition of the model's stiffness, natural frequencies and damping factors and the effects of vertical input motions and internal pressure on the model's characteristics and behavior, the load–deformation, the ultimate strength, the failure mode of the reinforced concrete portion and the liner plate are described here. The seismic safety margin that was evaluated by the energy input during the failure test to a design basis earthquake will be described in Part 3. The analytical results of simulation using the multi-lumped mass model will be described in Part 4.  相似文献   
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Some functional lanthanide metal complexes, such as acetylacetonato complexes, ethylenediaminetetraacetato complexes, were successfully applied for diagnostic technique. The authors are interested in investigating the structure and bonding in lanthanide and actinide metal complexes using 166Er, t55Gd, and 237Np Mtissbauer spectroscopies in connection with single-crystal and/or powder X-ray diffraction, making clear the differences on their structures as well as the differences in the participation of 4f and 5f orbitals in the chemical bonds. In this article, the crystal structures of two novel Gd(Ⅲ) acetylacetonato complexes, Gd(pta)3 · 2H2O (pta = 1,1,1 -trifluoro-5,5-dimethy 1-2,4-hexanedione) and Gd(bfa)3 · 2H2O (bfa = 1, 1, 1 -trifluoro-4-phenyl-2-4-butanedione) were reported. Though both of them were dihydrate and had distorted square antiprismatical structure, Gd(pta)3 · 2H2O crystallizes in the P 2 1/n (#14) monoclinic space group and its lattice parameters are a = 1.4141(6) nm, b = 1.0708(3) nm, c =2.2344(4) nm, β =952.4(2)°, and Gd(bfa)3· 2H2O crystallizes in P 212121 orthorhombic space group and its lattice parameters were a = 1.322 (1) nm, b = 2.295 (1) nm, c = 1. 0786(8) nm. In the meantime, the authors had finished a systematic investigation on the ^155Gd Mossbauer isomer shift (δ) of various Gd(Ⅲ) metal complexes having a different coordination number (C.N.) and different ratios coordinating oxygen to nitrogen. A tendency for the 6 value to decrease with an increase in the C.N, and the number of the nitrogen atom coordinating to Gd was confirmed. This indicated that the Gd-O and/or Gd-N bond in the investigated Gd(Ⅲ) metal complexes had a small covalent contribution, which was possible to be deduced from the O and/or N atoms of the lisands donating electrons to 6s, 5d, and 4f orbitals of Gd.  相似文献   
25.
Keratan sulfate (KS) oligomers with well-defined structures were synthesized by keratanase II (KSase II)-catalyzed transglycosylation. N-Acetyllactosamine [Galbeta(1-->4)GlcNAc; LacNAc] oxazoline derivatives with sulfate groups at the C-6 (1 a) and both the C-6 and the C-6' (1 b) were prepared as transition-state analogue substrate monomers for KSase II. Monomer 1 a was effectively oligomerized by the enzyme under weak alkaline conditions, to give alternating 6-sulfated KS oligomers (2 a) in good yields, and with total control of regioselectivity and stereochemistry. KSase II also recognized 1 b, which provided fully 6-sulfated KS oligomers (2 b) in good yields under similar conditions. Nonsulfated LacNAc oxazoline was difficult to oligomerize enzymatically. These results imply that the catalysis mechanism of KSase II involves a sugar oxazolinium ion that requires the 6-sulfate group in the GlcNAc residue not only in hydrolysis of KS chains, but also in oligomerization of oxazoline monomers. This is the first report of KSase II-catalyzed transglycosylation to form beta(1-->3)-glycosidic bond through a substrate-assisted mechanism.  相似文献   
26.
Pd-Ag thin films were prepared by the RF sputtering method on a Pyrex glass substrate to give monophasic alloys. Oxidation of allylic alcohols using the films gave selectively , -unsaturated carbonyl compounds in the presence of O2; highly dispersed Pd species on Ag, Pd7Ag93 showed 95% selectivity for acrolein from allyl alcohol at 473 K.  相似文献   
27.
DNA recognition by a ß-sheet is discussed in the lightof crystal structures of the MetJ and Arc repressors. The DNAbinding geometry of a ß-sheet can be understood interms of (i) close fitting of the two surfaces and (ii) matchingof residue and base positions. A ß-sheet is not entirelyflat but has a curvature. A ß-sheet of the Met-Arcfamily faces the DNA major groove with its convex surface; thelocal DNA major groove is deepest at the centre. The ß-sheetfollows 6 bp; every two residues face the DNA and the firstand fifth residues, which are separated by 13.2 Å, bind,respectively, to the third and sixth bases, which are separatedby 13.5 Å, on the same DNA strand.  相似文献   
28.
Partitioning of organic substrates by thermoresponsive polymer having N‐acryloylaminoalcohol moieties in aqueous phase has been studied. Thermoresponsive polymers, such as poly(N‐isopropylacrylamide) (PNIPAAm) and poly(NIPAAm‐coN‐acryloyl‐(±)‐alaninol) (poly(NIPAAm‐co‐HIPAAm)), were found to concentrate several organic substrates into the hydrophobic field generated during their phase transition. The amount of the substrates recoverd from the polymer phase mainly depended on the hydrophobicity of the substrates. Aqueous solutions of PNIPAAm (lower critical solution temperature, LCST = 33°C) and poly(NIPAAm‐co‐HIPAAm) (LSCT = 41°C) containing 1‐phenylethanol showed LCSTs at 22°C and 33°C, respectively. The changes of LCSTs indicate that specific interactions such as hydrogen bonding between the side chain functionalities of the polymers and the substrates influence the phase transition behavior. Moreover, new optically active polymers having chiral aminoalcohol moieties have been synthesized by copolymerizations of NIPAAm with N‐acryloylaminoalcohols such as N‐acryloyl‐(S)‐alaninol and N‐acryloyl‐(S)‐prolinol. The (R)/(S) ratio of 1‐phenylethanol recovered from poly(NIPAAm‐coN‐acryloyl‐(S)‐alaninol) and poly(NIPAAm‐coN‐acryloyl‐(S)‐prolinol) were determined to be 75/25 and 68/32, respectively. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 3458–3464, 2013  相似文献   
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30.
We developed tetranucleotide-repeat microsatellite markers for the masu salmon (Oncorhynchus masou) complex. 454 pyrosequencing was used to discover repeat motifs, and seven polymorphic microsatellite-primer sets were identified. The number of alleles detected at each locus ranged from four to 24 and the expected heterozygosity varied from 0.57 to 0.92. Cross-subspecies amplification for O. m. masou, O. m. ishikawae and O. m. subsp. was successful. These microsatellites can be utilized in studies of genetic structure, genetic diversity, and intra- and inter-subspecific hybridization, making a contribution to conservation and management of the Oncorhynchus masou complex.  相似文献   
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