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31.
A 64-kbyte snoopy cache memory was developed. The modified double word-line architecture with word-line buffers resulted in a large-size memory and a time-multiplex snoop operation by the pseudo-two-port method with a single-port cell. The flexible expandability was achieved by cascading multiple cache memories. The device was successfully implemented with 1.0-μm double-polysilicon and double-metal CMOS technology. Low-power sense amplifiers and comparators limited power dissipation to 0.5 W at 40 MHz  相似文献   
32.
Space-based radar can provide wide-area surveillance and theatre defence against targets in the air, on land, and at sea. This paper describes the airborne and ground-moving target indication problems, and examines environmental and system issues that impact space-based radar design. Radar design and signal processing techniques are presented that help target detection in the presence of clutter, jamming, and noise. Cost-performance trade-offs are used to derive radar signal processing baselines (configurations) that are proposed as candidate solutions  相似文献   
33.
This study is the first report in which the relationship between the progression of renal involvement in Henoch-Sch?nlein purpura (HSP) and various factors was evaluated using a multivariate analysis. Sixty-five (33.5%) of 194 patients with HSP developed renal involvement from three days to 17 months after the onset of the disease. The plasma coagulation factor XIII (F XIII) activity of 97 patients was examined, and 51 (54.3%) of them showed a decreased activity. A univariate analysis showed that an age at the onset of more than seven years, persistent purpura and a decreased F XIII activity all increased the risk of developing renal involvement. A Cox regression model analysis indicated severe abdominal symptoms, persistent purpura and decreased F XIII activity to be significant risk factors and their hazard ratios were 3.26, 11.53 and 2.27, respectively. Corticosteroid treatment had a hazard ratio of 0.36 and was considered to decrease the risk of developing renal involvement. Based on these findings, patients who have the risk factors for renal involvement should be treated with corticosteroids at the onset of the disease to prevent developing renal involvement.  相似文献   
34.
Three new saponins, named palustrosides I, II and III, together with azukisaponins II, V and soyasapogenol B monoglucuronide, were isolated from the aerial parts of Lathylus palustris L. var. pilosus Ledeb. The structures of palustrosides I, II and III were identified as 3-O-beta-D-glucopyranosyl-(1-->2)-beta-D-glucuronopyranosides of soyasapogenol E, abrisapogenol E, and bredemolic acid 28-O-beta-D-glucopyranoside, respectively, by spectroscopic and chemical methods. As part of our studies on hepatoprotective drugs, we also examined the hepatoprotective effects of these saponins towards immunologically induced liver injury in primary cultured rat hepatocytes. The activity of the disaccharide group was greater than that of the trisaccharide group. This information regarding the structure-activity relationships substantiated previously obtained data. Structure-hepatoprotective relationships for the sapogenol moiety suggested that the hydroxyl group at C-30 reduces the hepatoprotective effect. On the other hand, the carbonyl group at C-22 may be equivalent to a hydroxyl group at C-22 in terms of hepatoprotective action. Oleanolic acid-type saponins also exhibited hepatoprotective action.  相似文献   
35.
We investigated the influence of alcohol and the low protein diet upon rat pancreas. Rats were separated in four groups, 1) Control diet group (Cont), 2) Alcohol diet group (Al), 3) Low protein diet group (Lp), 4) Low protein and alcohol diet group (Lp+Al). They were fed on isocaloric liquid diet compulsorily through the gastric tube. They were sacrificed 3, 6, 12 weeks after. By the light microscopic observation on the rat pancreas which were fed for 12 weeks, lipid droplets in the acinar cells were observed in all groups other than Cont. Apoptosis was founded in Lp and Lp+Al groups. Protein plugs were observed in all groups, and no relation was found between the plugs and the location of the injured acinar cells. By the electromicroscopic observation, in Lp+Al group, acinar cells were typically injured (ER dilation, atrophic nuclei, mitochondria degeneration, etc.) and mesenchymal cells appeared among acinar cells. These results suggest that alcohol causes pancreatic acinar cell injury directly, and relative low protein diet helps to turn it worse.  相似文献   
36.
The combining of the outputs of two inverters using interphase reactors is a widely used method for supplying large AC drives rated at more than several thousand kilowatts. Certain drawbacks are associated with this method, such as high acoustic noise and high losses due to the interphase reactors. To overcome this problem, in this paper a new low‐acoustic‐noise and high‐efficiency drive system using an open‐winding AC motor and two space vector modulated inverters is proposed. This configuration consists of a three‐level inverter with switching once per cycle and a two‐level inverter of about 1 kHz switching frequency, connected to the opposite terminals of the open‐winding motor. With the proposed configuration, good current waveforms and high efficiency can be obtained. © 2003 Wiley Periodicals, Inc. Electr Eng Jpn, 144(3): 46–57, 2003; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10157  相似文献   
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38.
Peripheral mononuclear cells from 47 patients suffering from Japanese cedar pollinosis were stimulated with crude pollen extract of Cryptomeria Japonica (CJ) to evaluate the effect of CJ-specific immunotherapy. The stimulation index (SI) with crude pollen extract of CJ in the patients with excellent and good clinical outcome was significantly lower than those with poor outcome. The SI increased with the increasing symptoms in a dose dependent manner. In the patients under immunotherapy for long period, the good clinical outcome and low SI were gained. These results suggest that peripheral lymphocyte proliferation test should be a good objective indicator for allergen-specific immunotherapy.  相似文献   
39.
The choice of the mould powder for slab casting is a difficult task because mould powders have many important functions during the continuous casting of steel. CaF2 is a key ingredient in conventional mould slags since it reduces the viscosity, the liquidus temperature and the break temperature. Fluorine in mould powders is undesirable from the environmental and health points of view due to the following reasons: (i) evolves easily from slags, producing health-injurious gaseous substances, such as hydrofluoric acid; (ii) creates problems for storage and utilisation of solid waste and (iii) causes machinery corrosion. Aim of the present work is to describe the development of a new F-free mould powder for low carbon steel slab casting replacing CaF2 with B2O3. Laboratory tests and industrial trials were performed considering the technological parameters viscosity, break temperature and crystallisation tendency. From laboratory tests it was concluded that important technological parameters are similar when comparing the F-bearing mould powder (reference) and the new F-free B-bearing mould powder for low carbon steel slab casting: viscosity at 1300°C, break temperature, and crystallisation tendency. It was observed during industrial trials that a significant decrease of the submerged entry nozzle erosion was observed. The results were similar when comparing the F-bearing and the F-free performance: slag pool thickness measurements, melting behaviour, Al2O3 absorption, mould powder consumption and slabs superficial quality.  相似文献   
40.
Extreme ultraviolet (EUV) spectroscopy has been developed for impurity diagnostics in HL-2A tokamak. The EUV spectrometer consists of an entrance slit, a holographic varied-line- space (VLS) grating, a back-illuminated charge-coupled device (CCD) and a laser light source for optical alignment. Spectral lines in wavelength region of 20-500 A observed from HL-2A plasmas were analyzed to study the impurity behavior. Spectral and temporal resolutions used for the analysis were 0.19A at CV (2×33.73 ,h,) and 6 ms, respectively. It was found that carbon, oxygen and iron impurities were usually dominant in the HL-2A plasma. They almost disappeared when the siliconization was carried out. Although the EUV spectra were entirely replaced by the silicon emissions just after the siliconization, the emissions were considerably decreased with accumulation of discharges. Aluminum and neon were externally introduced into the HL-2A plasma based on laser blow-off (LBO) and supersonic molecular beam injection (SMBI) techniques for a trial of the impurity transport study, respectively. The preliminary result is presented for time behavior of EUV spectral lines.  相似文献   
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