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排序方式: 共有2112条查询结果,搜索用时 359 毫秒
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Q. Shan J. Wang F. Yang H. Ding C. Liang Z. Lv Z. Li Z. Zeng 《Journal of veterinary pharmacology and therapeutics》2014,37(3):222-230
The fluoroquinolone antimicrobial drug marbofloxacin was administered to yellow cattle intravenously and intramuscularly at a dose of 2 mg/kg of body weight in a two‐period crossover study. The pharmacokinetic properties of marbofloxacin in serum, inflamed tissue‐cage fluid (exudate), and noninflamed tissue‐cage fluid (transudate) were studied by using a tissue‐cage model. The in vitro and ex vivo activities of marbofloxacin in serum, exudate, and transudate against a pathogenic strain of Pasteurella multocida (P. multocida) were determined. Integration of in vivo pharmacokinetic data with the in vitro MIC provided mean values for the area under the curve (AUC)/MIC for serum, exudate, and transudate of 155.75, 153.00, and 138.88, respectively, after intravenous dosing and 160.50, 151.00, and 137.63, respectively, after intramuscular dosing. After intramuscular dosing, the maximum concentration/MIC ratios for serum, exudate, and transudate were 21.13, 9.13, and 8.38, respectively. The ex vivo growth inhibition data after intramuscular dosing were fitted to the inhibitory sigmoid Emax equation to provide the values of AUC/MIC required to produce bacteriostasis, bactericidal activity, and elimination of bacteria. The respective values for serum were 17.25, 31.29, and 109.62, and slightly lower values were obtained for transudate and exudate. It is proposed that these findings might be used with MIC50 or MIC90 data to provide a rational approach to the design of dosage schedules which optimize efficacy in respect of bacteriological as well as clinical cures. 相似文献
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对张集矿采煤沉陷区的现状进行了调查,指出了沉陷区及其流域存在着水质污染、富营养化、农药残留、毁林开荒、水土流失、崩岸严重、水生生态环境恶化等诸多问题,提出了生态修复、生态重建等对策,以改善采煤沉陷区的环境质量。 相似文献
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Mingchun Lv Han Zhang Kalin Mei Zhiyan Wang 《Journal Of Aquatic Food Product Technology》2020,29(3):220-228
ABSTRACTThe effects of high pressure (100–500 MPa) treatment on myofibrillar protein (MP) contents and distribution of water in Solenocera melantho muscle were investigated. The results showed that the shrimp treated with 200 MPa had the highest shelling score, and the solubility of MP in meat of shrimp treated with 300 MPa was significantly reduced. Moreover, the surface hydrophobicity of MP increased with increasing pressure. Treatment of shrimp with 200–300 MPa high pressure partially converted the structure of MP from an α-helix structure to a β-sheet structure, allowing for greater exposure of the tryptophan residues present. Treatment of shrimp with 100–200 MPa led to a significant loss in the amount of immobilized water in shrimp muscle. However, the treatment did not significantly change the moisture distribution. Overall, pressures of 100 to 200 MPa are considered the most suitable for the processing of S. melantho. 相似文献
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QI Ling XU Jun-jie ZHAO Dong-hai HAN Lei JI Peng-yan WANG Wei-yao Lv Shi-jie 《园艺学报》2014,30(9):1584-1589
AIM:To explore the effect of component II of broccoli polypeptide on the apoptosis in glioma cells. METHODS:Human glioma SHG-44 cells were cultured and divided into control group and 3, 10, 30 and 100 mg/L component II of broccoli polypeptide groups. Cell viability was detected by MTT assay. The apoptotic rates were examined by Annexin V/PI staining. The morphological changes of the cells were observed under inverted microscope. The protein expression of Bax and Bcl-2 was detected by immunocytochemistry and Western blotting. The protein level of caspase-3 was also examined by Western blotting. RESULTS:Treatment with component II of broccoli polypeptide for 24 h, 48 h or 72 h induced significant inhibition of viability of SHG-44 cells in a time- and dose-dependent manner. The results of Annexin V/PI staining showed that the apoptotic rates were increased in treatment groups in a dose-dependent manner. The density of glioma cells was decreased after treated with increasing concentrations of the drug, and the apoptotic bodies were observed under inverted microscope at 72 h. The results of immunocytochemistry and Western blotting showed that the expression of Bax protein was increased but Bcl-2 protein expression was decreased, and the ratio of Bax/Bcl-2 was increased significantly compared with control group (P<0.05 or P<0.01). The level of caspase-3 protein was increased in 30 and 100 mg/L component II of broccoli polypeptide groups compared with control group (P<0.01). CONCLUSION:The component II of broccoli polypeptide increases the ratio of Bax/Bcl-2 and activates caspase-3 protein, thus inducing the apoptosis of glioma cells. 相似文献
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Xiangbing Mao Mei Lv Bing Yu Jun He Ping Zheng Jie Yu Quyuan Wang Daiwen Chen 《畜牧与生物技术杂志(英文版)》2014,5(1)
Oxidative stress can induce abnormal tryptophan metabolism. The present study was mainly conducted to determine the effect of dietary tryptophan levels on oxidative stress in the liver of weaned pigs challenged by diquat. A total of 36 PIC piglets weaned at 21 days of age were randomly allotted to 1 of 3 diets containing dietary tryptophan levels of 0.18, 0.30, and 0.45% for 14 d. On day 8, the piglets were injected intraperitoneally with sterile 0.9% NaCl solution or diquat (10 mg/kg body weight). During the first 7 d of trial, increasing dietary tryptophan levels enhanced average daily gain (P = 0.09) and average daily feed intake (P = 0.08), and decreased the feed efficiency (P < 0.05) of piglets. The growth performance was decreased by diquat injection (P < 0.05). Diquat injection also decreased the activities of the superoxide dismutase (SOD) and glutathione peroxidase (GPx) in the plasma and liver (P < 0.05), increased plasma malondialdehyde (MDA) (P < 0.05) and urea nitrogen (P < 0.05) concentrations, and enhanced MDA concentration (P = 0.09) and tryptophan 2,3-dioxygenase (TDO) activity (P = 0.07) in liver of piglets. Increasing dietary tryptophan levels could attenuate the effects of diquat injection on the MDA (P = 0.06) concentration and the activities of SOD (P = 0.09) and GPx (P = 0.05) of the liver, and plasma urea nitrogen (P = 0.06) concentration in the piglet. There was a synergistic role for increasing TDO activity in the liver between dietary tryptophan levels and diquat injection (P < 0.05). These results suggest that increasing dietary tryptophan levels could attenuate the oxidative stress of the liver in weaned piglets intraperitoneally injected with diquat via enhancing the antioxidant capacity. 相似文献
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