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91.
Fullerene derivatives which have carboxylic acid moiety effectively inhibited glutathione reductase activity. Preincubation of the reductase and fullerene derivative at 37°C enhanced the inhibition activity.  相似文献   
92.
The two different molecular weight hyperbranched polymers (HBP(L)-PA-Ac and HBP(H)-PA-Ac) with both phosphonic acid group as a functional group and acryloyl group as a cross-linker at the chain ends were successfully synthesized as a new thermally stable proton-conducting electrolyte. The cross-linked electrolyte membranes (CL-HBP-PA) were prepared by their thermal polymerizations using benzoyl peroxide and their ionic conductivities under dry condition and thermal properties were investigated. The ionic conductivities of the low molecular weight CL-HBP(L)-PA membrane and the high molecular weight CL-HBP(H)-PA membrane were found to be 1.2 × 10−5 and 2.6 × 10−6 S cm−1, respectively, at 150 °C under dry condition, and showed the Vogel–Tamman–Fulcher (VTF) type temperature dependence. Both membranes were thermally stable up to 300 °C, and they had suitable thermal stability as electrolyte membranes for the high-temperature fuel cells under dry condition. Fuel cell measurements using a single membrane electrode assembly cell with both cross-linked membranes were successfully performed.  相似文献   
93.
We aimed to investigate the effect of methotrexate (MTX) on microRNA modulation in rheumatoid arthritis fibroblast-like synovial cells (RA-FLS). RA-FLS were treated with MTX for 48 h. We then performed miRNA array analysis to investigate differentially expressed miRNAs. Transfection with miR-877-3p precursor and inhibitor were used to investigate the functional role of miR-877-3p in RA-FLS. Gene ontology analysis was used to investigate the cellular processes involving miR-877-3p. The production of cytokines/chemokines was screened by multiplex cytokine/chemokine bead assay and confirmed by ELISA and quantitative real-time PCR. The migratory and proliferative activities of RA-FLS were analyzed by wound healing assay and MKI-67 expression. MTX treatment altered the expression of 13 miRNAs (seven were upregulated and six were downregulated). Among them, quantitative real-time PCR confirmed that miR-877-3p was upregulated in response to MTX (1.79 ± 0.46-fold, p < 0.05). The possible target genes of miR-877-3p in RA-FLS revealed by the microarray analysis were correlated with biological processes. The overexpression of miR-877-3p decreased the production of GM-CSF and CCL3, and the overexpression of miR-877-3p inhibited migratory and proliferative activity. MTX altered the miR-877-3p expression on RA-FLS, and this alteration of miR-877-3p attenuated the abundant production of cytokines/chemokines and proliferative property of RA-FLS.  相似文献   
94.
Vestibular schwannomas are the most common tumor at the common cerebellopontine angle, followed by meningiomas. Differentiation of these tumors is critical because of the different surgical approaches required for treatment. Recent studies have demonstrated the utility of amide proton transfer (APT)-chemical exchange saturation transfer (CEST) imaging in evaluating malignant brain tumors. However, APT imaging has not been applied in benign tumors. Here, we explored the potential of APT in differentiating between schwannomas and meningiomas at the cerebellopontine angle. We retrospectively evaluated nine patients with schwannoma and nine patients with meningioma who underwent APT-CEST MRI from November 2020 to April 2022 pre-operation. All 18 tumors were histologically diagnosed. There was a significant difference in magnetization transfer ratio asymmetry (MTRasym) values (0.033 ± 0.012 vs. 0.021 ± 0.004; p = 0.007) between the schwannoma and meningioma groups. Receiver operative curve analysis showed that MTRasym values clearly differentiated between the schwannoma and meningioma groups. At an MTRasym value threshold of 0.024, the diagnostic sensitivity, specificity, positive predictive value, and negative predictive values for MTRasym were 88.9%, 77.8%, 80.0%, and 87.5%, respectively. Our results demonstrated the ability of MTRasym values on APT-CEST imaging to discriminate patients with schwannomas from patients with meningiomas.  相似文献   
95.
Taiheiyo coal was hydrogenated in phenanthrene, 9,10-dihydrophenanthrene, 1,2,3,4,5,6,7,8-octahydrophenanthrene and perhydrophenanthrene under 10 MPa (initial pressure) of hydrogen or nitrogen with or without stabilized nickel as catalyst at 400 °C for 15 min. Preasphaltene, asphaltene and oil conversions and the conversion of solvents were measured, and the amounts of hydrogen absorbed by coal from molecular hydrogen and from donor solvent were calculated. The main route of reaction appears to be the direct hydrogenation of coal by molecular hydrogen and the contribution of hydrogenation via the solvent was greater than in the case of the two rings solvent system.  相似文献   
96.
In this paper we introduce two methods for building LALR parsers for regular right part grammars (RRPGs). Both methods build a parser directly from a grammar, require no extra state or data structure, and can deal with all LALR RRPGs. The first method is quite simple. For almost all LALR RRPGs, including the majority of grammars with stacking conflicts, parsing actions are similar to those of LALR parsers for usual context free grammars. No extra action is required to recognize a handle in this case. For other LALR RRPGs, the right hand side of a production is checked to recognize a handle. The second method does not require checking of the right hand side of a production to recognize a handle. Instead, it records the number of conflicts in LR items and in the stack. Unlike previous methods, our method needs no extra data structure. Received: 23 September 1998 / 16 March 2001  相似文献   
97.
Summary A method for building small fast LALR parsers for regular right part grammars is given. No grammar transformation is required. No extra state of the LALR parser for the recognition of strings generated by a right part is required. At some reduce states the parser may refer to lookback states (states in which the parser may be restarted after the reduction). An optimizing algorithm to reduce these references is also given.  相似文献   
98.
We fabricated new 2.78‐in 1058‐ppi organic light‐emitting diode (OLED) displays. The displays used OLED devices with a tandem structure and a single structure and a field effect transistor (FET) using c‐axis aligned crystalline In–Ga–Zn–O (CAAC‐IGZO) for an active layer and employing the 1.5‐µm rule over a glass substrate. Even in the displays with such high resolution exceeding 1000 ppi, crosstalk that was observed in the lower luminance region was suppressed. The displays achieved high color reproducibility and reduced viewing angle dependence.  相似文献   
99.
In order to attain the true integration of computer-aided design and computer-aided manufacturing not only is a smooth flow of information required, but also decision making for both product design and process design must be synthesized. In this paper an integrated design process is proposed in which decisions concerning both product design and process design are simultaneously made. According to the proposed design procedures, an integrated optimization problem is formulated. This optimization is expressed as a multiobjective optimization problem which produces many Pareto optimum solution sets corresponding to combinations of materials used for parts. The algorithm for solving the problem is also presented. The proposed method is applied to designing a cylindrical co-ordinate robot, thereby demonstrating the effectiveness of conducting a simultaneous process through product design and process design.  相似文献   
100.
Vibrio parahaemolyticus is a marine bacterium causing foodborne disease. Occurrence of the bacterium was investigated in six species of edible crustaceans available from markets in mainland China. The bacterium was detected in 22 of 45 whole-body, shell, and feces samples, including mitten crabs, which are supposed to be produced in freshwater ponds. The mean densities ranged from 2.8 log CFU/g in mitten crabs (Eriocheir sinensis) to 5.1 CFU/g in giant tiger prawns (Penaeus monodon). In hemolymph and muscle samples collected axenically, V. parahaemolyticus was detected in all of the prawns at a mean density of 2.6 log most probable number (MPN)/g, in two of five striped stone crabs (Charybdis feriatus) at a mean density of 1.1 log MPN/ml, and two of five mangrove mud crabs (Scylla serrata) at a mean density of 1.3 log MPN/ml. When six mitten crabs were collected from two freshwater ponds in China and were examined, V. parahaemolyticus was not detected. It seemed that cross-contamination occurred among live crustaceans at the markets. The results suggest that proper handling, storage, and cooking of these crustaceans will be necessary to lessen the risk of foodborne illness from V. parahaemolyticus.  相似文献   
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