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991.
992.
We reported a case of a 22-year old female with a microscopic form of polyarteritis nodosa (PN) who initially manifested Beh?et's disease-like symptoms, such as fever, arthralgia, oral aphtha and erythema nodosum, and rapidly progressive glomerulonephritis (RPGN). On admission, her urinalysis showed active nephritic syndrome and her renal function rapidly deteriorated; serum creatinine levels elevated from 1.2 to 3.9 mg/dl within 2 weeks. Skin biopsy specimens from erythema showed panniculitis. Accordingly, she was treated with daily 30 mg of oral prednisolone and three-day intravenous pulse therapy of 1000 mg of methylprednisolone twice. After treatment, skin eruption and oral aphtha disappeared, and the serum creatinine level improved to 1.2 mg/dl. Percutaneous renal biopsy performed on the 28th day showed focal necrotizing glomerulonephritis and hyalinosis of small arteries. Immunofluorescence studies showed only trace stainings for IgG, IgA and beta lc. Electron microscopic findings revealed fusion of the foot process and swelling of endothelial cells, but no dense deposits. Anti-neutrophil cytoplasmic antibody (ANCA) was positive for IgG class with a 40-fold titer by indirect immunofluorescence test and showed a cytoplasmic pattern combined with high urinary IL-8 level (280.1 pg/ml). We diagnosed this case as a microscopic form of PN. ANCA titer and urinary IL-8 correlated positively with the disease activity, and were finally below 8-fold and 58.6 pg/ml, respectively after resolution of RPGN for 42 months. In this case, ANCA was useful not only for differential diagnosis of the patients with systemic vasculitis and crescentic glomerulonephritis, but also for evaluation of the disease activity.  相似文献   
993.
Partial oxidation of methane was carried out over fine particles of amorphous lanthanum oxides including 3B element and amorphous yttrium aluminum oxide. At low temperatures and low methane/oxygen ratios products were CO, CO2, C2 hydrocarbon, hydrogen and water, and no formaldehyde was detected. The discussion on the contribution of catalyst components to the reaction suggested that 3B elements substantially influenced methyl radical formation and consumption while rare earth elements sufficiently affected formaldehyde decomposition.  相似文献   
994.
995.
We are developing an ion trap system for nuclear physics research at INS using lasers and a Penning trap. It has several important features, i.e., no specificity to ion species, fast response due to dynamic trapping and hopefully a high trapping efficiency.  相似文献   
996.
A dynamic FEM (finite element method) and a strain gage method are applied to analyze the dynamic fracture toughness and SIF (stress intensity factor) for PMMA (polymethyl methacrylate). The analyses are carried out for plates with an edge crack subjected to one-point bending in a plane of the plate. A simple procedure that the present author has proposed is applied to the problem of using a triangular element of assumed constant strain on finite element analysis. The numerical simulation by FEM provides values for the applied forces as measured with the strain gages. Also, a crack initiation time is measured with the strain gage mounted around the crack tip. The dynamic fracture toughness is determined by adapting the crack initiation time to the simulation curve of the dynamic SIF calculated by the FEM. In this study, the usefulness of the method to determine the dynamic fracture toughness is investigated by comparing predictions with the experimental results for dynamic stresses and SIFs.  相似文献   
997.
998.
This paper deals with dispersed installation of voltage‐detection based shunt active filters for harmonic damping throughput a power distribution system. A main objective of the active filters is to achieve damping of harmonic propagation coming from series/parallel resonance between capacitors for power factor correction and line inductors in the distribution system. Either a harmonic current source or a harmonic voltage source is connected to a distribution system simulator consisting of two distribution feeders, each of which is rated at 200 V and 20 kW. A couple of active filters are installed to the simulator. As a result, it is clarified by experiment that dispersed installation on the end bus of each feeder is effective in attenuating the harmonic propagation. © 2001 Scripta Technica, Electr Eng Jpn, 138(1): 14–23, 2002  相似文献   
999.
Absolute measurements of the electron energy spectrum in a helium-neon mixture and in pure neon and xenon have been obtained by an energy analysis of a sample of electrons extracted through a small hole in the anode. The spectrum appears to be nearly Maxwellian for the lower pressures but deviates markedly from a Maxwellian at higher pressures. At higher pressures, the energetic part of the spectrum drops off faster, and one can describe this part by a Maxwellian of lower temperature than that for the bulk of the distribution. The average energies agree with those obtained from microwave measurements of the radiation temperature of the electrons if corrections are made for nonthermal distribution. Several production rates are computed with the help of the measured spectra, and they are related to the wall current, the power dissipation, and the possible electron depopulation of helium metastables. The production and destruction rates for the different parts of the energy spectrum have been formulated mathematically. A theoretical formula, which describes the actual spectra, has been derived for the faster part of the spectrum. For the helium-neon laser discharge we can say definitely that the de-excitation of helium metastables by electrons is negligible.  相似文献   
1000.
An electrically reprogrammable read-only-memory (REPROM) device, providing the fully decoded and on-board-writable functions, is described. The device consists of novel N-channel memory transistors with floating gate, non-volatile memory transistors, which enable electrically reprogramming operation. The memory transistor has been through more than 107 rewrite cycles with no gain facto (β) decrease. The memory device has been processed by the flat-MOS and the Si-gate technologies. It has a 2048 bit memory capacity, organized as 256 words of 8 bits. The polycrystalline silicon floating gate is covered with vapor-deposited silicon nitride. This allows selective write and erase operation, giving the memory device a new bit-level reprogrammable function.  相似文献   
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