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Ginkgo biloba extract (EGB) functions as a natural substantial antioxidant and hypolipidemic. Chronic alcohol abuse leads to sustained dyslipidemia characterized by hyperlipidemia and lipid peroxidation. Thus, the present study investigates the effect of EGB on lipid disorders induced by ethanol in rats. Male Sprague-Dawley rats were fed with ethanol (2.4 g/kg), and pretreated with a daily dose of low or high EGB (48 or 96 mg/kg, respectively). During the experiment, serum was collected on day 30, 60, and 90. Serum lipid profile, including lipid peroxidation, was determined by colorimetric methods. Our data showed that ethanol intake resulted in a time-dependent increase in serum levels of triglyceride (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C) and malondialdehyde (MDA), and a decrease of the ratio of high-density lipoprotein cholesterol (HDL-C) against TC. EGB prophylactic medication (48 and 96 mg/kg), especially at the high dose, significantly increased HDL-C content, and normalized the abnormal lipid profile and peroxidation in comparison to ethanol-fed only rats. These results suggest that ethanol results in time-dependent hypercholesterolemia, hypertriglyceridemia and promotes serum lipid peroxidation. EGB pretreatment prevents hyperlipidemia and ameliorates lipid peroxidation induced by ethanol.

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The mass-flow-rate characteristics of high-pressure pneumatic servo valves (HPSVs) have an important effect on the dynamic performance of high-pressure servo systems. However, these characteristics are difficult to obtain by theoretical calculations and flowmeter measurements owing to the compressibility of high-pressure gas. In this paper, a new measurement method of the mass-flow-rate characterization parameters of HPSVs is proposed based on the principle of the series connection sonic discharge of valve orifices. The effective cross-sectional area and critical pressure ratio of the servo valve orifices can be accurately and efficiently determined by connecting two valve orifices in series and exchanging the flow sequence of the two valve orifices. The two assumptions including the sonic and adiabatic discharge of the proposed measurement method were verified. A comparison between the test and simulation data showed that the accuracy of the measured effective cross-sectional area and critical pressure ratio of the HPSV was high. The measured critical pressure ratio ranged from 0.46 to 0.50, and the flow coefficient represented by the effective cross-sectional area variation decreased with increasing valve opening. These findings have general implications for the accurate design, analysis, and control of high-pressure pneumatic servo systems.