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1.
Background: Within the claudin (CLDN) family, CLDN12 mRNA expression is altered in various types of cancer, but its clinicopathological relevance has yet to be established due to the absence of specific antibodies (Abs) with broad applications. Methods: We generated a monoclonal Ab (mAb) against human/mouse CLDN12 and verified its specificity. By performing immunohistochemical staining and semiquantification, we evaluated the relationship between CLDN12 expression and clinicopathological parameters in tissues from 138 cases of cervical cancer. Results: Western blot and immunohistochemical analyses revealed that the established mAb selectively recognized the CLDN12 protein. Twenty six of the 138 cases (18.8%) showed low CLDN12 expression, and the disease-specific survival (DSS) and recurrence-free survival rates were significantly decreased compared with those in the high CLDN12 expression group. We also demonstrated, via univariable and multivariable analyses, that the low CLDN12 expression represents a significant prognostic factor for the DSS of cervical cancer patients (HR 3.412, p = 0.002 and HR 2.615, p = 0.029, respectively). Conclusions: It can be concluded that a reduced CLDN12 expression predicts a poor outcome for cervical cancer. The novel anti-CLDN12 mAb could be a valuable tool to evaluate the biological relevance of the CLDN12 expression in diverse cancer types and other diseases.  相似文献   
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3.
Summary The potato phosphorylase-catalyzed polymerization of α-D-glucose-1-phosphate (G-1-P) onto poly[styrene-block-(4-vinylbenzyl maltohexaoside)] (1) was performed at the molar ratios of [G-l-P]0 and [maltohexaose]0 of 35, 80, and 250. The product was found to be soluble in dimethyl sulfoxide, which was a good solvent for amylose, and showed the complex-formation with iodine, indicating that the product was assignable to poly[styrene-block-(styrene-graft-amylose)] (2). The quantitative analysis of the liberated phosphoric acid gave the average degree of polymerization o f the glucose unit (n) as 27, 5 1, and 180 for 2-I, 2-II, and 2-III, respectively. Received: 29 November 2002/Accepted: 22 December 2002 Correspondence to Toyoji Kakuchi  相似文献   
4.
The present paper includes experimental and analytical data on the fracture properties of a nickel-iron superalloy, a ferromagnetic austenite, at 4 K in magnetic fields of 0 and 6 T. The tensile, notch tensile and small punch tests are employed. A finite element analysis is also performed to convert the experimentally measured load-displacement data into useful engineering information. To interpret the results we review the available theory of the influence of magnetic field on the stress intensity factor for a crack in ferromagnetic materials.  相似文献   
5.
The porcine antral follicles, 3-6 mm in diameter, were dissected from the ovaries of mature pigs, and then granulosa and cumulus cells were isolated from each follicle. In atretic follicles, high activity of neutral Ca2+/Mg2+-dependent endonuclease and DNA ladder formation, estimated by electrophoresis, were noted in granulosa cells but not in cumulus cells. Extremely low activity of the endonuclease and no DNA ladder formation were observed in both types of cells obtained from healthy follicles. Moreover, apoptotic cells were observed histochemically among granulosa cells only. A good correlation (r = 0.987) between the endonuclease activity of granulosa cells and the progesterone/estradiol ratio of follicular fluid in each follicle was found. These results suggest that apoptosis occurs in granulosa cells but not cumulus cells in the atretic antral follicles in pigs.  相似文献   
6.
The Co/MFI(SiO2/Al2O3 = 30) were prepared by a precipitation method with NaOCl in alkali solutions exhibited high activities to N2 at 250 °C for the selective catalytic reduction (SCR) of NOx. These catalysts showed two UV–vis bands at 700 and 400 nm, indicating the presence of octahedral Co(III) as well as tetrahedral Co(II). The high SCR activity over such Co(III, II)/MFI(30) seems to come from Co(III)---O moieties. The Co(II)MFI(30) catalysts prepared from Co(II)Cl2 exhibited low SCR activities due to the presence of tetrahedral Co(II) ions in MFI. Less CO formation occurred over Co/MFI catalysts. The Fe/MFI(30) catalyst exhibited high activity due to the presence of some Fe---O species in MFI but more amount of CO were produced during SCR. H/MFI(30) catalyst exhibited a good SCR activity. However, more amount of carbonaceous deposits were produced on it. The correlation between acid concentration and SCR activity was discussed over H/MFIs.  相似文献   
7.
Anion exchange membranes with excellent durability were prepared by chemical modification of Nafion. The modification was achieved by transformation of the sulfonic acid group into quaternary ammonium group. Namely, Nafion membrane was first converted into an amide-type membrane. Reduction of the carbonxyl group to methylene followed by quaternarization with alkyl iodide resulted in the formation of an anion exchange membrane. The electric resistance of the resulting membranes depends on the equivalent weight of the starting membranes (4.4–6.0 Ω cm2 in 0.5N NaCl). The characteristics of the membranes are the excellent stability toward chemical substances such as organic solvents, oxidizing agents, acids, etc. For example, the membranes are stable in aqueous saturated chlorine solution at 60°C for 1000 hr.  相似文献   
8.
The temperature dependence of luminescence from a long-lasting phosphor (LLP), SrAl2O4 : Eu2+,Dy3+, exposed to ionizing radiation has been measured to understand the LLP luminescence mechanism. Evaluation of the decay constants of the LLP exposed to -, β- or γ-rays at temperatures from 200 to 390 K showed that the decay constant is divided into four components ranging from 10−4 to 10−1 s−1 with activation energies of 0.02–0.35 eV.

Total luminous intensity from the LLP with changing irradiation temperature has its maximum value around the room temperature. Irradiation at elevated temperature (390 K) has the total luminescence pattern with monotonous decrease as temperature rises. As a result of evaluating the temperature dependence of luminescence, the luminescence mechanism is considered as follows:

 

Author Keywords: Radiation detection; Long-lasting phosphor; Luminescence; Temperature dependence; Fade-out effect  相似文献   

9.
The light scattering from the spherulites of polyethylene terephthalate grown near the glass transition temperature has been investigated. The Hv scattering profiles can be reproduced by the sum of the ideal spherulite scattering with the distribution of spherulite radius and the isotropic scattering from randomly oriented crystallites. The ratio of optical anisotropies in the isotropic scattering to the ideal spherulite scattering is obtained by the method established to eliminate the effects of the number density of spherulites and the coefficient depending on the experimental conditions. It is found that the anisotropy ratio is almost independent of the crystallization time and of temperature above 106 °C, while it is larger at a crystallization temperature of 103 °C. The spherulitic structure is discussed in terms of the anisotropy ratio.  相似文献   
10.
Most stable secondary structures and their stabilization energies of the TAR RNA with +1 to +104 nucleotide-sequence region were calculated at different temperatures by using thermodynamic parameters for RNA structure prediction. The most stable secondary structure has one bulge and one loop within the region of +20 to +40 nucleotide sequence, and its stabilization energy at 37 degrees C was -46.3 kcal mol-1. The interaction of a TAR bulge oligomer (TARBO) with arginine (Arg) which was in the binding site of a Tat protein was also investigated by CD measurements. The addition of Arg did not affect the CD spectrum of TARBO. The result was different from that of the RNA oligomer with both bulge and loop.  相似文献   
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