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1.
实验以大菱鲆(Scophthalmus maximus)幼鱼[(14.00±0.02)g]为研究对象,采用2×4双因素设计,设2个VE水平(0和75 mg/kg)和4个L-肌肽水平(0、50、100和200 mg/kg),研究VE和L-肌肽对其生长、抗氧化、非特异性免疫及血清生化指标的影响。实验共分8组,每组3个重复,每个重复46尾鱼,实验周期为8周。结果显示:(1)在饲料中添加75 mg/kg VE显著提高了大菱鲆幼鱼增重率(WGR)和特定生长率(SGR)(P < 0.05),L-肌肽添加量≤100 mg/kg对实验鱼生长性能无显著影响(P>0.05),添加量为200 mg/kg时鱼体WGR、SGR和蛋白质效率(PER)显著降低,饲料系数(FCR)显著升高(P < 0.05);(2)VE和L-肌肽对血清谷胱甘肽过氧化物酶(GSH-PX)、过氧化氢酶(CAT)活性和丙二醛(MDA)含量及肝脏总抗氧化能力(T-AOC)、超氧化物歧化酶(SOD)活性和MDA含量均具有显著的交互作用(P < 0.05),在VE 75 mg/kg水平下,L-肌肽添加量为50和100 mg/kg时血清GSH-PX活性最高,L-肌肽添加量为100和200 mg/kg时血清CAT活性最高且与添加量为50 mg/kg差异不显著(P>0.05),添加100 mg/kg肝脏T-AOC和SOD活性达到最高且50 mg/kg组的SOD与100 mg/kg组差异不显著(P>0.05),主效应结果显示,VE显著提高了血清T-AOC、SOD及肝脏CAT活性(P < 0.05),L-肌肽显著提高了血清T-AOC(P < 0.05);(3)VE和L-肌肽对血清补体C3和LZM活性交互作用显著,在75 mg/kg VE水平下,L-肌肽添加量为50 mg/kg时,补体C3水平最高(P < 0.05),主效应显示,VE和L-肌肽对血清总蛋白(TP)影响均不显著(P>0.05);(4)添加VE显著降低了血清总胆固醇(TCHO)和甘油三酯(TG)含量(P < 0.05),添加L-肌肽显著降低了血清TG含量,且在L-肌肽50 mg/kg时达到最低。综合考虑大菱鲆幼鱼[(14.00-39.43)g]的生长性能、抗氧化性能、非特异性免疫及血清生化指标得出,在实验配方条件下(鱼油70 g/kg,大豆卵磷脂10 g/kg),添加VE 75 mg/kg时,L-肌肽的适宜添加量为50 mg/kg。  相似文献   
2.
华北地区针叶林下凋落物层化学性质的研究   总被引:10,自引:0,他引:10  
森林凋落物中贮积了大量的有机、无机养分物质,它是森林土壤自然肥力的重要来源之一。在森林生态系统中,养分物质的内部循环主要是通过凋落物来实现的。在分解、转化过  相似文献   
3.
While compulsory licensing (CL) is described in the TRIPS agreement as flexibility to protect public health by improving access to medicines in developing countries, a recent literature contends adversely that CL may harm public health. Therefore, this article intends to evaluate the usefulness of CL in the South through the prism of obligations and goals entrusted to patent holders (the effective and non‐abusive exploitation of patents in order to achieve industrial and health developments) and in light of experiences in Thailand and Brazil regarding access to antiretroviral drugs. In this way, it shows that the obligations assigned to patent holders were better served by the recipients of CL and brought significant health and industrial benefits in the two high middle‐income countries. In particular, CL allowed the scaling‐up of free and universal access to antiretroviral drugs by assuring the financial sustainability of these public health programs endangered by monopolistic practices from patent holders.  相似文献   
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This study aimed to determine the phytochemical components, microbial inhibitory effectiveness and antioxidant properties of Aerva lanata plant extracts. The whole plant showed various medicinal applications in folklore and traditional medicine in various parts of the world. The organic extracts such as ethanol, ethyl acetate, chloroform, acetone, water and methanol were subjected for various phytochemical analysis and confirmed for the existence of flavonoids, glycosides, terpenoids and alkaloid containing components. Alternatively, the extracts were performed for the antibacterial activities against the microbial pathogens and antioxidant properties. Results indicated that, the solvent extracts showed prominent activity against the tested strains. The MIC concentrations of plant were detected from 5 mg/ml to 40 mg/ml. The plant extract was highly effective against E. coli and E. aerogenes and the MIC was 5 mg/ml. In addition, the extracts noted promising antioxidant activities. The antioxidant activities were dose dependent manner. In conclusion, A. lanata extracts showed that significant major phytochemicals and effective antioxidant and anti-microbial properties.  相似文献   
6.
A new series of N-acylhydrazone derivatives of 2-mercaptobenzimidazole (2-MBI) has been synthesized through S-alkylation with 1-bromotetradecane and N-alkylation with ethyl-2-chloroacetate. The resulting ester was synthetically modified through hydrazine hydrate to acyl hydrazide which was condensed with aromatic aldehydes to afford the title N-acylhydrazones (4-17). Chemical structures of the newly synthesized compounds have been confirmed through mass, FT-IR and 1HNMR techniques. In vitro free radical scavenging and α-glucosidase inhibition activities of the compounds were investigated with reference to the standard ascorbic acid and acarbose, respectively. Amongst the target compounds, 13 showed the highest inhibition in DPPH scavenging assay (IC50 = 131.50 µM) and α-glucosidase inhibition potential (IC50 = 352 µg/ml). We extended our investigations to explore the mechanism of enzyme inhibition and conducted docking analysis by using Molecular Operating Environment (MOE 2016.08). A homology model for α-glucosidase was constructed and validated using Ramachandran plot. Docking studies were also carried out on human intestinal α-glucosidases. In view of the importance of the nucleus involved, the synthesized compounds might find extensive medicinal applications as reported in the literature.  相似文献   
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In evaluating the relative expression of copper-zinc and manganese superoxide dismutase (CuZnSOD and MnSOD) in vivo in states like Down syndrome in which one dismutase is present at increased levels, we measured activities of both enzymes, in tissues of control and transgenic mice constitutively expressing increased levels of CuZnSOD, during exposure to normal and elevated oxygen tensions. Using SOD gel electrophoresis assay, CuZnSOD and MnSOD activities of brain, lung, heart, kidney, and liver from mice exposed to either normal (21%) or elevated (>99% oxygen, 630 torr) oxygen tensions for 120 h were compared. Whereas CuZnSOD activity was elevated in tissues of transgenic relative to control mice under both normoxic or hyperoxic conditions, MnSOD activities in organs of transgenic mice were remarkably similar to those of controls under both conditions. To confirm the accuracy of this method in quantitating MnSOD relative to CuZnSOD expression, two other methods were utilized. In lung, which is the organ exposed to the highest oxygen tension during ambient hyperoxia, a sensitive, specific ELISA for MnSOD was used. Again, MnSOD protein was not different in transgenic relative to control mice during exposure to air or hyperoxia. In addition, lung MnSOD protein was not changed significantly by exposure to hyperoxia in either group. In kidney, a mitochondrion-rich organ, SOD assay, before and after inactivation of CuZnSOD with diethyldithiocarbamate, was used. MnSOD activity was not different in organs from air-exposed transgenic relative to control mice. The data indicated that expression of MnSOD in vivo was not affected by overexpression of the CuZnSOD and, therefore, the two enzymes are probably regulated independently.  相似文献   
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