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61.
蒲公英经济价值很高,我国野生蒲公英资源分布比较广泛,但数量有限,利用率较低,不能满足市场需求.该文介绍了适用于露地蒲公英人工栽培技术,综述了蒲公英的应用现状,以期为蒲公英的深度开发提供理论参考.  相似文献   
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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 (Pmultocida) 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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吕影 《绿色科技》2014,(7):222-223
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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ABSTRACT

The 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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大西洋金枪鱼延绳钓主要渔获种类及其分布   总被引:1,自引:1,他引:1  
樊伟  周甦芳  沈建华 《海洋渔业》2003,25(3):130-135
根据收集的有关文献和海上调查资料,分析了大西洋金枪鱼延绳钓生产的主要渔获品种的生物学特性、捕捞生产情况及管理措施等。此外,还根据FAO建立的金枪鱼生产数据库,采用GIS软件制作了大西洋金枪鱼延绳钓主要渔获种类捕捞产量的地理空间分布图。并分析了其资源的空间分布特征。  相似文献   
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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   
69.
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   
70.
为了筛选出成本低、肥效高的复合肥,本研究以辣椒为试验材料,进行了5种复合肥田间试验。试验结果表明:澳特尔复合肥(N、P、K配比为25∶10∶16)和洋洋复合肥(N、P、K配比为20∶10∶10)对辣椒生长效果最好,产量最高,比对照处理1分别增产14.6%和11.2%,达到极显著水平。此两种复合肥可以在同等肥力条件下大面积推广使用。  相似文献   
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