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61.
植物转脂蛋白 (plant lipid transfer proteins, LTPs) 是高等植物中广泛存在的多基因编码的小分子碱性蛋白. 本研究室已经证明白菜和豌豆LTPs可分别被内源胞浆可溶性和膜结合钙依赖性蛋白激酶 (calcium-dependent protein kinase, CDPK) 磷酸化. 为深入研究CDPK对白菜钙调素结合蛋白10 (calmodulin-binding protein-10, CaMBP10) 的磷酸化性质及特征, 本文从拟南芥可溶性蛋白粗提物中检测到1个分子量约为54 kD的CDPK对CaMBP10有磷酸化作用. 研究表明, 组蛋白可增强 CDPK对CaMBP10的磷酸化活性, 促进磷酸化进程. 而且组蛋白和Ca2+对CDPK具有协同调节效应, 二者共同作用时比Ca2+单独作用时, 激酶的活力增强约12倍. 此外, 不同组蛋白对CDPK的激活能力不同, 组蛋白1对该激酶活性的激活能力要比组蛋白3高约8倍. 相似文献
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随着教育改革的不断深入和信息化建设的不断推进,现代教学媒体与课程有效整合,以成为课堂的必需。现代教学媒体走进生物课堂,为课堂教学提供了良好的互动平台,极大的提高了教学效率,为学生的知识能力创新开拓了空间。 相似文献
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随着素质教育改革的不断深入,建设有效课堂成为现代教育所追求的重要目标。作为初中阶段一门非常重要的学科,生物课堂的有效教学建设是必然的趋势。本文主要介绍了在新课改背景下建设初中生物课堂有效教学的策略。 相似文献
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白羽扇豆(Lupinus albus L.)对磷和生长素表现出高度的根系形态和生理可塑性反应, 然而磷和生长素如何调节根形态和生理特性以及它们对根形态和生理的交互效应尚不清楚. 本研究通过水培实验旨在评价磷(0或250 μmol/L)和生长素(10-8 mol/L NAA)对白羽扇豆根特性的影响及其交互效应. 结果表明, 缺少磷和生长素施用均明显改变了白羽扇豆的根形态(主根长度减少、一级侧根数目增加和排根大量形成)和生理特性(质子释放、柠檬酸分泌和酸性磷酸酶活性增加). 外源生长素的施用增加了缺磷白羽扇豆根系的响应度和敏感性. 磷和生长素对白羽扇豆根系形态和生理具有明显的交互作用. 主成分分析表明, 磷解释了根特性64.8%的信息, 而生长素解释了21.3%的信息, 表明磷供应对白羽扇豆根特性的影响比外源生长素施用更为重要. 白羽扇豆能够通过协调根系形态和生理对外部刺激(如缺磷和施用生长素)作出应答, 以及优化根形态和生理之间的关系从而最大化获取磷素资源. 相似文献
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目的:探讨2种不同血液净化方式对慢性肾脏病(CKD)患者低血钙、高血磷及高血清甲状旁腺激素的改善效果。方法:选择2011年9月到2014年9月在我院接收维持性血液透析(MHD)的患者64例,随机分为HDF组和HP-HD组各32例;HDF组采用血液透析滤过(HDF)治疗,HP-HD组采用血液灌流(HP)联合血液透析(HD)治疗;分别在治疗前及治疗后3周采血检测血钙、血磷和全段甲状旁腺激素(iPTH)。结果:治疗三周后,与治疗前相比较,两组患者血磷、iPTH显著下降,血钙显著上升,均有显著性差异(P0.05);HP-HD组患者血磷、iPTH下降较HDF组更为显著,均有显著性差异(P0.05)。结论:HDF和HP联合HD均能有效调节血钙、清除血磷和iPTH水平,但HP联合HD较HDF效果更佳。 相似文献
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为了研究露地栽培向设施大棚栽培转变对土壤重金属含量的影响,对武汉市郊区露地和设施塑料大棚两种栽培条件下菜田土壤重金属Cd、Cr和Pb各形态含量及分布特征进行了研究。结果显示,露地和大棚栽培条件下土壤重金属元素Cr和Pb各种形态含量之间没有明显差异,但Cd各种形态含量间有显著差异;从露地到大棚,土壤中Cd酸可提取态含量从露地的0.62 mg/kg上升到大棚的1.19 mg/kg,其次是Cd残渣态、有机结合态、氧化态和碳酸盐结合态;Cd总含量从露地的0.79 mg/kg升高到大棚的1.58 mg/kg,显著超过土壤环境质量标准中的Cd含量标准值(0.3 mg/kg),达到严重污染水平。Cd碳酸盐结合态和氧化态占总量的比例有所降低,而酸可提取态占总量的比例有所升高。说明从露地到设施大棚栽培,促使了土壤中部分Cd碳酸盐结合态和氧化结合态向酸可提取态转变,提高了土壤中Cd的生物有效性。因此,在设施大棚栽培快速发展的情况下,要加强重金属Cd对土壤污染的治理,减少重金属Cd对蔬菜的毒害。 相似文献
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Effects of simulated nitrogen deposition on fine root morphology,nitrogen and phosphorus efficiency of Pinus massoniana clone under phosphorus deficiency
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《植物生态学报》2016,40(11):1136
Aims In forest ecosystems with phosphorus (P) deficiency, the impact of atmospheric nitrogen (N) deposition on nutritional traits related to N and P uptake potentially affect plant growth and vegetation productivity. The objective of this study was to explore the effects of simulated N deposition on fine root morphological characteristics and effiency of N and P absorption in Pinus massoniana under under low P stress.
Methods Two clones of P. massoniana seedling with different P efficiency (high P efficiency 19-5 vs. low P efficiency 21-3) were used. A two-year pot experiment was applyed with treatments of two P conditions, (i.e. homogeneous low P availability vs. heterogeneous low P availability) and three N deposition levels (0, 30 and 120 kg N·hm-2·a-1; i.e., N0, N30, or N120, respectively) .
Important findings 1) The growth of P. massoniana seedling was interactively affected the three factors: simulated N deposition, P condition and genotypes. Simulated N deposition increased the seedling height and dry mass under heterogeneous P deficiency, but did not significantly affect those traits under homogeneous P deficiency. Under heterogeneous P deficiency and N120 treatment, the seedling height and dry mass of clone 19-5 were 1.1 times and 1.6 times higher than that of clone 21-3, respectively. 2) Fine root length and surface area decreased as root diameter increased. N deposition significantly stimulated proliferation of fine root with diameter ≤1.5 mm, while roots with diameters ranged from 1.5 to 2.0 mm and over 2.0 mm were not influenced. The length of fine root ≤1.5 mm in diameter accounted for 90.4%-92.8% of the total root length and was not affected by N deposition. 3) Under the heterogeneous low P condition, clone 19-5 was found to respond to the simulated N deposition with increased root length and surface area in fine-root diameter class of ≤1.5 mm. Additionally, in compared with control, its N and P absorption efficiency were significantly enhanced 93.3% and 148.4%, respectively under N120 treatment. However, the N and P absorption efficiency of clone 21-3 was less affected by the simulated N deposition. The N and P use efficiency had no notable variation. Finally, we found that the proliferation of fine-root ≤1.5 mm in diameter and high N (P) absorption efficiency maybe the adaptive mechanisms of P. massoniana responding to atmospheric N deposition under P deficiency. 相似文献
Methods Two clones of P. massoniana seedling with different P efficiency (high P efficiency 19-5 vs. low P efficiency 21-3) were used. A two-year pot experiment was applyed with treatments of two P conditions, (i.e. homogeneous low P availability vs. heterogeneous low P availability) and three N deposition levels (0, 30 and 120 kg N·hm-2·a-1; i.e., N0, N30, or N120, respectively) .
Important findings 1) The growth of P. massoniana seedling was interactively affected the three factors: simulated N deposition, P condition and genotypes. Simulated N deposition increased the seedling height and dry mass under heterogeneous P deficiency, but did not significantly affect those traits under homogeneous P deficiency. Under heterogeneous P deficiency and N120 treatment, the seedling height and dry mass of clone 19-5 were 1.1 times and 1.6 times higher than that of clone 21-3, respectively. 2) Fine root length and surface area decreased as root diameter increased. N deposition significantly stimulated proliferation of fine root with diameter ≤1.5 mm, while roots with diameters ranged from 1.5 to 2.0 mm and over 2.0 mm were not influenced. The length of fine root ≤1.5 mm in diameter accounted for 90.4%-92.8% of the total root length and was not affected by N deposition. 3) Under the heterogeneous low P condition, clone 19-5 was found to respond to the simulated N deposition with increased root length and surface area in fine-root diameter class of ≤1.5 mm. Additionally, in compared with control, its N and P absorption efficiency were significantly enhanced 93.3% and 148.4%, respectively under N120 treatment. However, the N and P absorption efficiency of clone 21-3 was less affected by the simulated N deposition. The N and P use efficiency had no notable variation. Finally, we found that the proliferation of fine-root ≤1.5 mm in diameter and high N (P) absorption efficiency maybe the adaptive mechanisms of P. massoniana responding to atmospheric N deposition under P deficiency. 相似文献