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1.
Immunoglobulin G4-related disease (IgG4-RD) is a systemic disorder characterized by tissue fibrosis and intense lymphoplasmacytic infiltration, causing progressive organ dysfunction. Activation-induced cytidine deaminase (AID), a deaminase normally expressed in activated B-cells in germinal centers, edits ribonucleotides to induce somatic hypermutation and class switching of immunoglobulin. While AID expression is strictly controlled under physiological conditions, chronic inflammation has been noted to induce its upregulation to propel oncogenesis. We examined AID expression in IgG4-related ophthalmic disease (IgG4-ROD; n = 16), marginal zone lymphoma with IgG4-positive cells (IgG4+ MZL; n = 11), and marginal zone lymphoma without IgG4-positive cells (IgG4- MZL; n = 12) of ocular adnexa using immunohistochemical staining. Immunohistochemistry revealed significantly higher AID-intensity index in IgG4-ROD and IgG4+ MZL than IgG4- MZL (p < 0.001 and = 0.001, respectively). The present results suggest that IgG4-RD has several specific causes of AID up-regulation in addition to inflammation, and AID may be a driver of oncogenesis in IgG4-ROD to IgG4+ MZL.  相似文献   
2.
Pactamycin is an antibiotic produced by Streptomyces pactum with antitumor and antimalarial properties. Pactamycin has a unique aminocyclitol core that is decorated with 3-aminoacetophenone, 6-methylsaliciate, and an N,N-dimethylcarbamoyl group. Herein, we show that the adenylation enzyme PctU activates 3-aminobenzoic acid (3ABA) with adenosine triphosphate and ligates it to the holo form of the discrete acyl carrier protein PctK to yield 3ABA-PctK. Then, 3ABA-PctK is N-glycosylated with uridine diphosphate-N-acetyl-d -glucosamine (UDP-GlcNAc) by the glycosyltransferase PctL to yield GlcNAc-3ABA-PctK. Because 3ABA is known to be a precursor of the 3-aminoacetophenone moiety, PctU appears to be a gatekeeper that selects the appropriate 3-aminobenzoate starter unit. Overall, we propose that acyl carrier protein-bound glycosylated 3ABA derivatives are biosynthetic intermediates of pactamycin biosynthesis.  相似文献   
3.
This work demonstrated the first-ever cold-start operation of an ammonia (NH3)-fueled four-cylinder spark ignition engine with an on-board fuel reformer, applying autothermal reforming. In this system, an electrically heated NH3-air mixture was provided to a reforming catalyst and approximately 3 s was found to elapse between the start of engine rotation and the onset of combustion. Stable fast idle operation in conjunction with a cold start was realized with a H2-to-NH3 molar ratio of 2:1. Nearly zero NH3 emissions were achieved during cold start and fast idle until the engine warmed up, by adsorbing unburned NH3 passing through a three-way catalyst before the catalyst was sufficiently warmed up. The NH3 adsorption capacity of this system could be regenerated during the engine warm-up when the engine was running under lean conditions.  相似文献   
4.
In this study we investigate a method for accurately calculating the characteristics of salient‐pole synchronous machines assisted by permanent magnets. First, the operating principle of the machines is investigated by using both finite element analysis and a simple magnetic circuit. Then, a theoretical representation of the assist effect on the permanent magnets is derived based on the magnetic circuit. Finally, the measured and calculated results are compared in order to confirm the validity of the proposed calculation method. We show that the load characteristics of the proposed machine can be accurately estimated from the no‐load and short‐circuit characteristics of the conventional machine without permanent magnets, and the size and magnetization of the inserted permanent magnets.  相似文献   
5.
The flux‐modulating synchronous machine (FMSM) is a new type of multipole SM with nonoverlapping concentrated armature and field windings on the stator. This paper compares the output characteristics of two FMSMs through finite element analysis (FEA) and experiments. In both of the FMSMs, the attachment positions of the armature and field windings are swapped. To determine the reason for the discrepancies in their output characteristics, unsaturated inductances were calculated using a d‐q equivalent circuit. In addition, the calculated results of the inductances were confirmed through a visualization of the leakage fluxes using FEA. The results of the study show that the synchronous inductance can be reduced by attaching the armature winding to the air‐gap side of the stator teeth and that the reduction leads to an increase in output power.  相似文献   
6.
7.
In a previous paper, we proposed a novel linear synchronous motor with half‐wave‐rectified self‐excitation. A long‐stator‐type linear synchronous motor was built and its performance was verified by experiments. This paper presents a new current control method for the linear synchronous motor in order to achieve a wide range of speeds and high‐power operations. First, we propose a current control method for high‐thrust operation in the constant‐thrust region. This operation is realized by using the reluctance thrust resulting from the saliency of the linear synchronous motor. We also propose a control method that maximizes the ratio of the thrust to the voltage; this method can be used to expand the operating range. Wide‐range‐speed operation can be achieved by applying this new control method along with field‐weakening control. The thrust and operating characteristics of the proposed control methods are estimated by performing experiments and coupled electric and magnetic analysis.  相似文献   
8.
Accumulation of nitrous oxide in aerobic groundwaters   总被引:1,自引:0,他引:1  
N2O concentrations in the groundwaters collected in the Kanto District and Nagano Prefecture in Japan and five counties in New York State were determined. These N2O data were obtained from the water samples from wells, springs and seepages from soils in forests and cropping fields. The N2O concentrations in all samples greatly exceeded those of atmospheric equilibration. The average concentration of 690 nM N2O is one order of magnitude larger than that in deep ocean. All groundwaters of the present study were aerobic with a high level of NO3, but with the absence of NO2 and NH4+, and with a very low level of dissolved organic carbon. These characteristics suggest that the nitrate respiration in the aquifers is of little significance for the production of N2O.

ΔN2O/NO3 molar ratios in the groundwaters were between 10−4 and 10−2 (Δ indicates the excess gas over that which would be in equilibrium). This supports the above view since the observed N2O yield agrees with that reported for the production during an ammonia oxidation. If nitrification was indeed a major mechanism for the production of groundwater N2O, subsequent release of N2O from the aquifers that are polluted with nitrogen may deserve more close attention as a potential source of atmospheric N2O via diffusion and discharge.  相似文献   

9.
The photodegradation of polypropylene (PP) film was performed by a TiO2/polyethylene oxide (PEO)/plant oil paint photocatalyst system. The photodegradation underwent two stages of development as follows: Initially PP reacted with linoleic acid radical originated from the photoreaction of plant oil component. Second, the linoleic acid graft‐polymer was decomposed, and then PP chain scission was caused. The process was studied using methyl linoleate (ML) in detail. The melting point of the 24 h‐photodegraded PP slightly decreased, and those of the 48 h‐ and 96 h‐ones drastically did as compared with the pristine PP. The crystallinity (χc) decreased at the 48 h photodegradation time and drastically increased at the 96 h one. The 24 h‐photodegraded PP showed the 77% Young's modulus, 88% tensile strength, and 103% strain at break values to those of the pristine PP. The ML graft‐polymerization and decomposition brought about the PP plasticizing and chemi‐crystallization, causing the PP degradation. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 39909.  相似文献   
10.
The iron(III) chloride‐catalyzed Friedel–Crafts arylation of 4‐aryl‐4‐methoxy‐2,5‐cyclohexadienones, which were easily prepared by the phenyliodine(III) diacetate (PIDA)‐mediated oxidation of 4‐arylphenols in methanol, proceeded site‐selectively to form meta‐terphenyl (2,4‐diarylphenol) derivatives in good yields. The subsequent PIDA‐mediated oxidation and iron(III) chloride‐catalyzed Friedel–Crafts arylation of the resulting products gave the corresponding 2,4,6‐triarylphenol derivatives. The present method provides useful highly substituted polyarylated compounds.

  相似文献   

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