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51.
AN Salt MM Henson SL Gewalt AW Keating JE DeMott OW Henson 《Canadian Metallurgical Quarterly》1995,88(1-2):79-86
The experiments carried out on the model of immobilization stress permit establishing the antiulcer effect of preventive introduction of sodium succinate solution, milk serum solution and solution of milk serum with sodium succinate. A decrease in the degree and number of ulcers and in the integrative indices characterizing the ulcer process after introduction of the studied drugs was accompanied by a fall of the intensity of lipid peroxidation processes. 相似文献
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随着电力和电子技术的飞速发展,相应的元器件向高频化,小型化,高效率和节能的方向发展,从而对元器件用材料也提出了更高要求。为此,本文概述了冶金部钢铁研究总院近年来所研究的用于开关电源,脉冲变压器,传感器,电流互感器和电感器等方面的非晶软磁合金的性能及其应用概况。 相似文献
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Pacific whiting surimi wash water (SWW) proteinase was recovered by ohmic heating, ultrafiltration, and freeze-drying. By these processes, 5.9-fold purification was achieved. The most efficient step was ohmic heating, which concentrated the proteinase by 4.8 fold. Specific activity of the recovered SWW proteinase on casein and Z-Phe-Arg-NMec was 28.2 and 0.17 U/mg protein, respectively. The SWW proteinase showed good hydrolytic activity towards casein, acid-denatured hemoglobin and myofibrils. Acidification increased specific activity on all substrates tested but reduced thermal stability. β-Mercaptoethanol, dithiothreitol and urea enhanced activity against Z-Phe-Arg-NMec. Proteinase activity on Z-Phe-Arg-NMec showed an optimum pH of 4.0. The recovered proteinase showed 18.5% residual activity after 7 week storage at 4C. 相似文献
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A 50 year old man presented with sudden abdominal pain, abdominal distension and shock. At emergency laparotomy a large amount of blood was found in the peritoneal cavity. There was micronodular cirrhosis of the liver and the spleen was enlarged. The bleeding was traced to distended veins in the right paracolic gutter which were oversewn and the abdomen closed. A coagulopathy was diagnosed and treatment including high dose aprotinin commenced. However, he continued to bleed and at a second laparotomy the area of previous haemorrhage was packed. Further deterioration continued until death 12 hours later. Intraperitoneal haemorrhage from ectopic varices is a rare occurrence. There is a high mortality rate usually due to an advanced coagulopathy. This is the first report of aprotinin being used in an attempt to treat this. On the basis of this report aprotinin would not seem to be of benefit for this condition. 相似文献
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2座烟囱定向爆破拆除 总被引:2,自引:2,他引:0
介绍了2座分别高37m、45m砖砌烟囱定向爆破拆除的情况,给出了爆破方案,爆破参数和安全防护措施,爆破效果良好. 相似文献
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The authors previously reported that American shad (Alosa sapidissima) can detect sounds from 100 Hz to 180 kHz, with two regions of best sensitivity, one from 200 to 800 Hz and the other from 25 to 150 kHz [Mann et al., Nature 389, 341 (1997)]. These results demonstrated ultrasonic hearing by shad, but thresholds at lower frequencies were potentially masked by background noise in the experimental room. In this study, the thresholds of the American shad in a quieter and smaller tank, as well as thresholds for detecting stimulated echolocation sounds of bottlenosed dolphins was determined. Shad had lower thresholds for detection (from 0.2 to 0.8 kHz) in the quieter and smaller tank compared with the previous experiment, with low-frequency background noise but similar thresholds at ultrasonic frequencies. Shad were also able to detect echolocation clicks with a threshold of 171 dB re: 1 microPa peak to peak. If spherical spreading and an absorption coefficient of 0.02 dB/m of dolphin echolocation clicks are assumed, shad should be able to detect echolocating Tursiops truncatus at ranges up to 187 m. The authors propose that ultrasonic hearing evolved in shad in response to selection pressures from echolocating odontocete cetaceans. 相似文献