高温胁迫对葡萄叶片三项生理指标的影响

将葡萄幼苗置于高温胁迫条件下,通过测定叶片中脯氨酸、叶绿素和可溶性糖的含量来研究葡萄幼苗的抗热、抗水分胁迫的能力.结果表明：热激3h可溶性糖的含量达到最大值.葡萄叶片脯氨酸的含量在高温胁迫下明显高于对照,而叶绿素的含量和可溶性糖的含量则随胁迫时间的延长呈现“低-高-低”的波动.实验结果表明在短时间内葡萄幼苗具有快速抗热的机制.     

大麦黄花叶病抗性机理的初步研究

不同抗性的大麦品种（系）被黄花叶病毒侵染后,叶片中叶绿素,可溶性蛋白质,游离脯氨酸的含量有规律地变化,研究结果表明,感病后,大麦叶片内叶绿素,可溶性蛋白质含量下降,感病品种下降幅度大于抗性品种,而游离脯氨酸含量增加,抗性品种增加的幅度比幅度比感病品种大,同时发现,叶绿素,可溶性蛋白质,游离脯氨酸的含量与病情指数呈显著的负相关。     

基于深度神经网络-近似线性网络混合模型的电力系统状态估计方法

为提高电力系统实时状态估计的精度和计算效率,解决电网电压波动频发、潮流分布的不确定性剧增等问题,通过提出一种基于深度神经网络和近似线性网络模型的电力系统状态估计方法,研究了其在电网的应用。该方法将混合系统量测数据通过粒子滤波算法得到样本集,利用训练样本训练所提出的混合神经网络模型,最后将测试样本输入已建立的模型中获得系统状态的估计结果。通过IEEE118节点系统进行的负载数据仿真实验表明：基于混合神经网络模型的电力系统状态估计方法不仅能快速进行海量数据训练,还能有效避免过拟合;在实时状态估计的精度和计算效率方面,相较于高斯-牛顿法均有提高。可见所提方法在电力系统实时状态估计方面具有一定的应用价值。     

Cyclin A1 is a p53-induced gene that mediates apoptosis, G2/ M arrest, and mitotic catastrophe in renal, ovarian, and lung carcinoma cells

We were the first to identify cyclin A1 as a p53-induced gene by cDNA expression profiling of p53-sensitive and -resistant tumor cells [Maxwell S. A. and Davis G. E. (2000) Proc. Natl. Acad. Sci. USA 97, 13009–13014]. We show here that cyclin A1 can induce G2 cell cycle arrest, polyploidy, apoptosis, and mitotic catastrophe in H1299 non-small cell lung, TOV-21G ovarian, or 786-0 renal carcinoma cells. More cdk1 protein and kinase activities were observed in cyclin A1-induced cells than in GFP control-induced cells. Thus, cyclin A1 might mediate apoptosis and mitotic catastrophe through an unscheduled or inappropriate activation of cdk1. Two primary renal cell carcinomas expressing mutated p53 exhibited reduced or absent expression of cyclin A1 relative to the corresponding normal tissue. Moreover, renal carcinoma-derived mutant p53s were deficient in inducing cyclin A1 expression in p53-null cells. Cyclin A1 but not cyclin A2 was upregulated in etoposide-treated tumor cells undergoing p53-dependent apoptosis and mitotic catastrophe. Forced upregulation of cyclin A2 did not induce apoptosis. The data implicate cyclin A1 as a downstream player in p53-dependent apoptosis and G2 arrest. Received 1 November 2005; received after revision 17 February 2006; accepted 13 April 2006     

杨树嫩茎质外体中脯氨酸含量测定方法的建立

采用高效液相色谱法HPLC对微透析液进行痕量脯氨酸的检测,研究了痕量脯氨酸柱前衍生化的方法。采用苯异硫氰酸酯PITC-乙腈溶液和三乙胺-乙腈溶液对透析液中痕量脯氨酸进行衍生化后,通过环己烷萃取,得到透析液中痕量脯氨酸衍生化的最适方法,无需后续处理可直接进样,并确定了HPLC检测条件:岛津Inertsil ODS-SP色谱柱(250 mm×4.6 mm, 5 μm);柱温:31 ℃;流动相A:0.05 mol·L^-1醋酸钠溶液;流动相B:乙腈-流动相A(1:1);洗脱条件:A:B(50:50);流速:1.0 mL·min^-1;检测波长:254 nm;进样量:20 μL。脯氨酸加标回收率为95.1 ％~104.2 %。同时,对3种杨树质外体透析液中的脯氨酸进行了测量。     

Amino acid and allozyme frequency changes in overwinteringChymomyza amoena (Diptera: Drosophilidae) larvae

Summary Proline is accumulated by overwinteringC. amonea larvae. Mortality averages over 50% by spring. PGM^F in the population shifts from 70% in summer to less than 50% during winter, increasing again in summer. Product synthesis from stored glycogen may be mandated in dipteran larvae also using larval proteins for cold hardiness when completion of development is delayed until spring.Thanks are gratefully extended to Derek Lamport and Patrick Muldoon of the MSU/DOE Plant Biology Laboratory for the amino acid analyses. Thanks are also extended to Jerry Wolfe, Director of Mt. Lake Biological Station in summer, 1985 and Blaine Cole, Director beginning summer, 1986 for research space, to the University of Virginia, Charlottesville for a fellowship for the work at MLBS in summer, 1986 and to all the property owners in Michigan and Virginia who allowed collection at their orchards, farms, gardens or residences. Apples in January and March, 1986 were from a university research orchard. — This paper is dedicated to Hampton L. Carson on his retirement.     

Proline accumulation as a reliable indicator of monocarpic senescence in rice cultivars

Summary Proline content proportionally increased with leaf age as well as during aging in darkness of excised leaf segments collected from the flag, second and third leaves of the Jaya cultivar of rice. BA significantly suppressed, whereas ABA augmented, the rise of proline level in the leaf segments. Proline also increased in the attached flag, second and third leaves of all the 4 rice cultivars with the progress of reproductive development but the pattern of its accumulation was non-sequential in Jaya and Ratna and sequential in Masuri and Kalojira. Although proline accumulation was retarded and enhanced by treatment with BA and ABA, respectively, as foliar sprays, the mode of proline accumulation (non-sequential or sequential) remained unaltered.The financial assistance of the C.S.I.R., New Delhi, in the form of a research grant to MAC for carrying out the present investigation is acknowledged.     

遮荫条件下乌拉苔草叶片气孔阻力与脯氨酸、叶绿素含量的研究

通过对不同遮荫条件下乌拉苔草某些生理特性的研究表明,乌拉苔草叶片气孔阻力受遮荫的影响较大,遮荫直接影响气孔开闭．气孔阻力对环境的响应比较大。其中对气孔阻力影响最大的是叶温,随着遮荫度的增加而增加,风速和气孔阻力呈负相关;光量子通量密度对气孔阻力的影响较大,遮荫大其影响也大,体现出气孔阻力对环境的适应性强。遮荫条件下乌拉苔草叶片的脯氨酸含量比对照增加,说明遮光对脯氨酸积累有一定的影响;乌拉苔草叶片叶绿素含量受遮荫的影响很大,遮荫大叶绿素的积累也大,并随着季节的推移而增加。说明乌拉苔草在逆境下具有生态适应性。     

鄂尔多斯高原不同生境下中间锦鸡儿(Caragana.davazameii)叶片的游离脯氨酸、丙二醛含量以及POD活性的变化

通过对分布在鄂尔多斯高原不同生境的中间锦鸡儿叶片进行生理生化指标的测定,并选取具有明显生境差异的呼和浩特树木园移栽的中间锦鸡儿植株作为对比,探讨同一物种在不同生境下其体内游离脯氨酸、丙二醛含量(MDA)以及过氧化物酶(POD)活性的变化.结果表明:(1)生境差异明显的中间锦鸡儿生理调节方式也有明显差异,生境相近体内生理调节方式表现出趋同(2)野生中间锦鸡儿植株的POD活性均高于树木园移栽植株,进一步说明水分是影响中间锦鸡儿体内生理调节与代谢的主要生态因子.     

干旱及冻融胁迫对黑麦草抗氧化酶活性和脯氨酸质量比的影响

以冬牧70黑麦草为材料, 用聚乙二醇（PEG 6000）模拟干旱胁迫, 设置5%（D1),10%(D2),15%(D3)三种不同程度干旱（轻度、 中度、 重度）以及对照组（CK）, 温度为10,5,0,-5,0,5,10 ℃, 研究冻融及干旱胁迫对幼苗中抗氧化酶活性和脯氨酸质量比的影响. 结果表明： 单一干旱胁迫下黑麦草幼苗中超氧化物歧化酶（SOD）、 抗氧化物酶 （POD）活性和脯氨酸质量比均 增加; 冻融和复合胁迫下幼苗中SOD活性呈先升高后显著下降趋势, POD活性和脯氨酸质量比呈先升高后缓慢下降趋势, 在-5 ℃出现峰值, 与其他温度下的数值存在显著性差异（P<0.05）; 胁迫伤害下整体呈复合胁迫>单干旱胁迫>单冻融胁迫的趋势, 冻融胁迫下的伤害程度为重度干旱+冻融>轻度干旱+冻融>单一冻融>中度干旱+冻融, 复合胁迫对植物伤害出现叠加效应, 适当的干旱处理可缓解冻融对幼苗的生理损害. 因此植物通过提高抗氧化酶活性和渗透调节物质, 可缓解其遇到胁迫时的伤害.