玉米转基因在分子农业领域的研究进展

植物转基因技术开辟了作物遗传改良的新途径。近年来,随着植物反应器技术的多元化发展以及日趋成熟,以玉米为分子工厂合成一些高价值产品成为研究热点。笔者就以玉米为植物反应器,用其生产糖类、必需氨基酸、不饱和脂肪酸、维生素、微量元素、生物酶、疫苗、抗体等各种高价值分子代谢物进行了综述,以期为中国分子农业领域的研究与应用提供参考。     

p38MAPK信号通路选择性调节FSH对甾体生成 的诱导作用研究

利用乙烯雌酚（DES）处理23日龄SD大鼠，分离卵巢颗粒细胞(GC)进行无血清培养。结果表明，FSH (50ng/m1) 处理GC，可迅速激活有丝分裂原蛋白激酶（p38 MAPK），FSH处理5min便可观察到磷酸化的p38 MAPK；FSH处理30min，磷酸化的p38 MAPK水平达到最高;向培养液中加入H89(蛋白激酶A抑制剂，10μM)，则显著抑制了FSH对p38 MAPK的激活作用，提示这种激活作用依赖于蛋白激酶A(PKA)。用 SB203580(p38MAPK抑制剂，20μM)抑制p38 MAPK激活，则进一步提高了FSH对孕酮和甾体生成快速调节蛋白（StAR）的诱导作用，同时降低了FSH对雌激素生成的促进作用(p<0.01)。RT-PCR结果显示：抑制p38 MAPK活性后，FSH对StAR mRNA刺激作用明显增强，但对细胞色素P450芳香化酶（P450arom）mRNA的诱导作用却减弱了(p<0.05)。激光共聚焦和蛋白印迹结果显示：在GC中，StAR蛋白主要分布在线粒体中；与对照组相比，FSH显著提高了StAR的荧光强度和蛋白水平；抑制p38MAPK活性则增强了FSH对StAR蛋白表达的诱导作用。     

Operational Deflection Shape Analysis of Large Scale Electromechanical System

Operational Deflection Shapes of large scale electromechanical system can be ex-tracted directly from multipoints response of the operating system by using of the modal shape analy-sis method. Thev can be used for engineers evaluating the practical dynamic beavior of the largescale elecltromechanical system,checking the existence of local reso,iance of the Stibsystem. and in-dentifying the wcakened positions of the rigidity of structure, In this paper the method of measuringand extracting the operational deflection shal1e of the electromecha nical system is given and theavailability of operational deflection shape is proved by analyzing the actual vibration of a large ex-haust fan system as an example.     

东方百合生殖器官诱导鳞茎的繁殖技术研究

以东方百合的花托、花丝、花柱和子房为材料，直接诱导鳞茎和低温锻炼繁殖技术研究。结果表明，4种生殖器官均可直接诱导出鳞茎，分化能力依次为花托〉花丝〉花柱〉子房；鳞茎的中层鳞片分化能力最强；鳞茎分化和生根的最佳培养基是MS＋KT0．05mg／L＋NAA0．2mg／L＋白糖5％＋琼脂0．5％；试管鳞茎移栽的适宜方法是生根的试管鳞茎在2-5℃下，保持60d后栽培到泥炭土：珍珠岩=8：2的基质中，锻炼培养20d。     

NONLINEAR COUPLING IN THERMOELAST1C THEORY AND A SOLUTION TO THE PROBLEM IN THE HALF SPACE

It's recommended that the term coupled in temperature and strain is nonlinear and is significant in thermoelastic theory. Using the solution of linear coupled and uncoupled theory and selecting appropriate general coordinates, authers approach the nonlinear coupled problems with a variational method. A solution to the problem in half space, is given. It is shown that the difference between the nonlinear coupled theory and the linear coupled or uncoupled theory would be notable when the amplitute of temperature is much larger than that of the reference slate.     

TEM INVESTIGATION ON AGED ION-NITRIDING LAYER OF PURE IRON

The phase transformation in the diffusion layer after slow cooling and aging of pure iron ion -nitrided was investigated with TEM. Refering to principle of Moire method measuring macroscopical strain, the values of coherent strain at interfaces between a" and aN phases were determined by means of TEM analyses.     

玉米品种结实性差的原因及预防措施

2005年沧州市夏播玉米果穗出现了不同程度的缺粒、缺行现象,有的果穗结实仅有一半,一般减产30%～70%,个别地块颗粒无收.针对上述问题,我们组织技术人员深入田间进行了认真的调查分析,基本明确了造成玉米结实性差的主要原因及预防措施.     

VARIABLE DAMP STRUCTURAL RELIABILITY DUE TO MULTIPLE RANDOM EXCITATIONS AND SENSETIVITY ANALYSIS

The reliability of random vibration is discussed,and then by using the first order perturbation method and with the aid of relation of the systemic response function to the first order sensetivity of variable damp parameter, the rate of change of structural reliability indication is derived, therefore the constraint equation to guarantee reliability for the structural optimization design is proved and the satisfactory result is obtained,test and the practicability of this method is tested.     

RECREATING SMALL SEAMLESS TUBE MILLS BY PIERCING INSFEAD OF ROLLING

This paper discuss the effects of automatic plug mills in small seamless tube mills. Far from traditional ideas,the auther comes rp with mew ideas, which adot the mew process of replacing rolling by piercing,a huge sum of economical interests and great social benefits will be gained.