Size matters: a view of selenocysteine incorporation from the ribosome

This review focuses on the known factors required for selenocysteine (Sec) incorporation in eukaryotes and highlights recent findings that have compelled us to propose a new model for the mechanism of Sec incorporation. In light of this data we also review the controversial aspects of the previous modelspecifically regarding the proposed interaction between SBP2 and eEFSec. In addition, the relevance of two recently discovered factors in the recoding of Sec are reviewed. The role of the ribosome in this process is emphasized along with a detailed analysis of kinkturn structures present in the ribosome and the L7Ae RNA-binding motif present in SBP2 and other proteins. Received 2 September 2005; received after revision 28 September 2005; accepted 12 October 2005     

基于逻辑上的群的同态

利用剩余格值逻辑的语义方法讨论了群的L－fuzzy同态和强L－fuzzy同态的概念与性质，给出了L－fuzzy同构的定义和fuzzy化的同态基本定理。     

银杏外种皮中活性成分的分离与鉴定

报道了一种通过溶剂提取，乙醚和碱液萃取，以及酸还原，由银杏外种皮为原料得到氢化白果酸、白果酚、银杏黄酮类物质的新工艺方法，利用薄层层析、高效液相色谱、红外光谱对产品进行的定性定量测量和结构分析。初提物生物测定结果表明：对几种常见菌的抑制率为60％～80％，对几种常见害虫的杀虫率70％～80%。纯化物活性测定结果表明：黄酮类物质对几种菌的抑制率均超过70％，氢化白果酸对小麦白粉茵治疗和保护作用可分别大于80%。     

贺兰山老鹳草属(Geranium L.)植物新资料

报道了从贺兰山采集到的内蒙古新记录种曲嘴老鹳草(Geranium forrestii Kunth)、圆柱根老鹳草(G.farreri Stapf)以及贺兰山新记录种老鹳草(G.wilfordii Maxim.)     

Identification and biological significance of 4-methyl-3Z,5-hexadienoic acid produced by males of the gall-forming tephritidsUrophora cardui (L.) andUrophora stylata (Fab.) (Diptera: Tephritidae)

Summary A new natural substance has been identified in the rectal ampullae of gall-forming fruit flies. The substance was found to be the only volatile compound in the rectal ampulla of maleUrophora cardui andUrophora stylata. GC-MS methods were used to characterize its structure as 4-methyl-3Z,5-hexadienoic acid. Physiological parameters such as the amount of the acid at different ages and under different conditions were investigated. The biological significance of the new volatile as an arresting pheromone was tested in several bioassays. The arrestant function could not be established, but the results gave hints of a territorial function between conspecific males. The results are discussed with respect to gland morphology and predictions of communication models among fruit flies.     

ASYMPTOTICS OF THE “MINIMUM L_1-NORM”ESTIMATES IN A PARTLY LINEAR MODEL

ＡＳＹＭＰＴＯＴＩＣＳＯＦＴＨＥ“ＭＩＮＩＭＵＭＬ＿１－ＮＯＲＭ”ＥＳＴＩＭＡＴＥＳＩＮＡＰＡＲＴＬＹＬＩＮＥＡＲＭＯＤＥＬ￥ＳＨＩＰｅｉｄｅ；ＬＩＧｕｏｙｉｎｇ（ＩｎｓｔｉｔｕｔｅｏｆＳｙｓｔｅｍｓＳｃｉｅｎｃｅ，ＡｃａｄｅｍｉａＳｉｎｉｃａ，Ｂｅ...     

同余方程ab≡1（modn）在模N原根集中的分布性质

设整数ｎ≥３存在原根，对任意给定的整数０＜ｘ＜ｎ且（ｎ，ｘ）＝１，显然存在唯一的０＜ｘ＜ｎ使各ｘｘ≡１（ｍｏｄｎ）．如果ｘ和ｘ具有相反的奇偶性，定义数ａ为ｌｅｈｍｅｒＤＨ数。本文主要研究同余方程式ｘｘ≡１（ｍｏｄｎ）在模ｎ的原根集Ａ＝｛ａ｜１≤ａ＜ｎ且ａ是模ｎ的原根｝中解的分布性质与原根集Ａ中ｌｅｎｈｍｅｒ数的分布性质，给出了几个有趣的渐近公式。     

绿豆愈伤组织的诱导及其保持的研究

本文以绿豆无菌苗的下胚轴、子叶为外植体,研究植物激素的使用与绿豆愈伤组织诱导及其保持的试验结果,供从事有关研究者参考。     

变形L非线性逼近

给出 L 变可解族的概念及若干性质,证明了最佳逼近元具有交错性,得到了广义有理逼近与具约束有理逼近的强唯一性定理.     

陕北紫茉莉种子的化学成分研究

对陕北紫茉莉(Mirabilis jalapa L)种子的结构、组成比例及主要化学成分进行了研究，经解剖及分析测试表明：陕北紫茱莉种子由黑色外壳、种衣、黄色内壳及胚乳组成，其组成比例分别为42．70％、O．35％、26．10％、30．85％；其中黑色外壳含木质素36．30％，黄色内壳含脂肪25．O％，胚乳舍淀粉92％并舍有多肽、黄酮、萜类、内酯、香豆素等多种活性物质。同时论述了紫茉莉种子开发应用前景。