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901.
902.
采用3×3随机交叉试验设计,研究中能中蛋白水平下日粮VA、VD3对肉仔鸡生产性能的影响。1日龄AA肉仔鸡540只随机分为9组,每组3个重复,每重复20只鸡。3个VA添加水平为3000、6000、12000IU/kg;3个VD3添加水平为200、400、800IU/kg;0~3和4~6周龄基础日粮代谢能、粗蛋白水平分别为12.34MJ/kg,21%;12.76MJ/kg,19%。结果表明:①日粮VA水平对体增重、耗料量、料重比、存活率均无显著影响(P>0.05);②随VD3添加水平的增加,体增重、耗料量、存活率显著增加(P<0.05);③综合考虑生产性能和经济效益,认为0~3和4~6周龄肉仔鸡日粮VA添加量均以3000IU/kg较为适宜,VD3添加量均以800IU/kg较为适宜。 相似文献
903.
904.
Suárez-Bonnet A Herráez P Martín de las Mulas J Rodríguez F Déniz JM Espinosa de los Monteros A 《Veterinary journal (London, England : 1997)》2011,(3):345-351
14-3-3 σ protein is a negative cell cycle regulator, with both reduced and elevated levels associated with cancer in humans. This study assessed the expression of this protein in canine mammary tissues using immunohistochemistry and Western blotting. 14-3-3 σ was detected in 97% of the mammary tissue samples examined and was found in both myoepithelial (MECs) and epithelial (ECs) cells. Expression levels were elevated and reduced in neoplastic ECs and MECs, respectively (P < 0.001). Intense expression of 14-3-3 σ was detected in neoplastic ECs infiltrating blood vessels and lymph nodes and suggests a possible role for this protein in the malignant transformation of mammary neoplasms. Moreover, double immunostaining for 14-3-3 σ and the MEC – specific marker p63, confirmed that 14-3-3 σ is a highly sensitive marker of MECs since all p63 – positive cells were also positive for 14-3-3 σ. However, this protein is not exclusive to MECs as ECs also labelled positively. 相似文献
905.
通过10年(2001~2010)的驯化栽培,将具有高抗旱、耐风沙的野生灌木阿拉善沙拐枣从民勤沙区引种至兰州获得成功.试验结果表明:经过驯化栽培,该种植物在兰州地区人工栽培条件下,能够正常生长、结籽和成熟,从播种(移栽)出苗(萌发)至结籽成熟生长160d以上.植株高度80~113cm,5月出苗(萌发),8月开花,10月种子成熟.干鲜比1:4.4,茎叶比1:2.0.种子产量538.4kg/hm2(千粒重64.46g),青草产最12809.8kg/hm2.根系发达,生长速度快,种植第5年的植株地上和地下生物量各接近50%,其根系具有很强的同土护坡能力.营养含量中等,可消化吸收率高.阿拉善沙拐枣在我国黄土高原干旱、半干旱地区可作为水土保持和生态建设灌木树种使用,亦可饲用.种植方式以育苗移栽效果最佳,耐粗放管理,种苗成活后不再需浇水、施肥. 相似文献
906.
907.
芳氧苯氧基丙酸酯类除草剂的应用进展 总被引:2,自引:0,他引:2
芳氧苯氧基丙酸酯(简称APP)类除草剂是近二十年发展起来的活性很好的新型除草剂,用于防除一年或多年生禾本科杂草。本文主要综述了APP的发展历史、作用机理、主要品种以及应用研究进展。 相似文献
908.
Stefan Tresch Jennifer SchmotzKlaus Grossmann 《Pesticide biochemistry and physiology》2011,99(1):86-95
The mode of action of endothall, an herbicide which was reported to inhibit plant protein phosphatases 1 (PP1) and 2A (PP2A), was investigated. For initial characterization, a series of bioassays was used for comprehensive physiological profiling of endothall effects which suggested a phytotoxic mode of action similar to mitotic disrupter herbicides. Unlike known microtubule disrupters, endothall did not inhibit soybean tubulin polymerization in vitro. As shown in meristematic corn root tips, endothall distorted the orientation of cell division plane and microtubule spindle structures which led to cell cycle arrest in prometaphase. In tobacco BY-2 cells, malformed spindles together with prometaphase arrest of nuclei and abnormal perinuclear microtubule patterns were detected as early as 4 h of endothall treatment. These effects were also observed after treatment with other protein phosphatase inhibitors, cantharidin and okadaic acid, which phenocopied the mitotic changes described in tonneau1 (ton1) and tonneau2 (ton2) Arabidopsis mutants. These mutants are defective in TONNEAU2 (TON2) protein, a regulatory subunit of PP2A, which governs cell division plane and microtubule orientation. Therefore, PP2A/TON2 phosphatase complex is suggested to be an in planta molecular target of endothall. However, in BY-2 cells, additional effects of endothall, including inhibition of S-phase initiation and DNA synthesis, detected by 5-ethynyl-2′-deoxyuridine (EdU) incorporation, and condensed nuclei arrested in late mitosis were observed which were not reported in Arabidopsiston1 and ton2 mutants. This result indicates that two additional checkpoints in cell cycle were blocked by endothall which are probably not associated with TON2-pathway inhibition. Possibly, inhibition of PP1 and/or other PP2A protein phosphatases are involved in the regulation of these cell cycle phenomena. 相似文献
909.
Jalal Pourahmad Mir-Jamal HosseiniSoudeh Bakan Mahmoud Ghazi-Khansari 《Pesticide biochemistry and physiology》2011,99(1):105-110
Paraquat is a highly toxic herbicide that is used in most countries without restriction. The cytotoxic action of paraquat is mediated by reactive radicals that are products of its metabolic reduction in cells. It has already been hypothesized that some angiotensin-converting enzyme inhibitors (e.g., captopril and enalapril) could show antioxidant and radical scavenging activity through their structural thiol groups, increasing antioxidant enzymes production or nitric oxide synthesis. In this study the hepatoprotective effect of captopril and enalapril against paraquat induced oxidative stress cytotoxicity was evaluated in isolated rat hepatocyte. Subtoxic concentrations of captopril (0.2 mM) and enalapril (0.2 mM) significantly (p < 0.05) protected the hepatocytes against paraquat (2 mM) induced oxidative stress cytotoxicity markers including: cell lysis, reactive oxygen species (ROS) generation, lipid peroxidation, glutathione depletion, mitochondrial membrane potential decrease, lysosomal membrane oxidative damage and cellular proteolysis. Moreover, we showed that non-thiol enalapril acts as well as thiol containing captopril at inhibiting oxidative stress cytotoxicity markers. Finally, our results support the hypothesis that it is the increase in nitric oxide synthesis and not the presence of the thiol group that accounts for the antioxidant activity of ACE inhibitors. 相似文献
910.
类钙粘蛋白对Cry3A毒素杀虫活性的影响 总被引:1,自引:1,他引:0
将克隆的黄粉虫类钙粘蛋白基因片段在大肠杆菌中表达纯化,并分析其对Cry3A毒素杀虫活性的影响,从而探讨黄粉虫类钙粘蛋白对Cry3A毒素杀虫活性的增效作用。黄粉虫类钙粘蛋白基因片段在大肠杆菌中表达产物为包涵体,经尿素变性后,用亲和纯化法可得到较纯的重组蛋白;随着类钙粘蛋白片段与Cry3A质量比值的升高,Cry3A毒素对黄粉虫的杀虫活性也逐步提高,当其比值为1时,活性达到最大,提高了2.5倍,而黄粉虫类钙粘蛋白片段对Cry3Am的杀虫活性却没有显著性影响。研究表明,黄粉虫类钙粘蛋白对Cry3A毒素的杀虫活性具有增效作用。 相似文献