T优6135

审定情况：2004年通过国家审定，审定编号：同审稻2004034；2005年参加长江中下游中籼迟熟组续试并同时进行生产试验。     

智利小植绥螨对土耳其斯坦叶螨、截形叶螨、朱砂叶螨的捕食作用

[目的]研究智利小植绥螨(Phytoseiulus persimilis)雌成螨对新疆三种主要害螨土耳其斯坦叶螨(Tetranychus turkestani Ugarov et Nikolski)、截形叶螨(Tetranychus truncatctus Ehara)、朱砂叶螨(Tetranychus cinnabarinus)的捕食功能反应,以及智利小植绥螨个体之间捕食的干扰反应.[方法]在27℃条件下,采用实验生态学方法,用HoUingⅡ型圆盘方程进行拟合.[结果]智利小植绥螨雌成螨和若螨对的反应均属于HollingⅡ型.智利小植绥螨雌成螨的捕食能力(a/Th值)远大于若螨;智利小植绥螨雌成螨对土耳其斯坦叶螨的攻击率最高为0.665,对朱砂叶螨的攻击率最低为0.214;对土耳其斯坦叶螨的捕食能力最强为10.726,对朱砂叶螨的捕食能力最弱为3.754;智利小植绥螨的寻找效应随着天敌密度的增加而降低.[结论]智利小植绥螨对土耳其斯坦叶螨、截形叶螨、朱砂叶螨捕食作用均属于HollingⅡ型,其捕食作用同时受到猎物密度和自身密度的影响.     

太空甜椒T100

太空甜椒T100是郑州市太空种苗开发部与中国空间技术研究院合作,由神舟三号宇宙飞船搭载,经过7天的轨道运行,受太空环境诱变而发生基因变异的甜椒新品种.这是目前为止我国利用宇宙飞船搭载技术培育成功的第一个甜椒品种.……     

Identification of a T helper cell-derived lymphokine that activates resting T lymphocytes

A novel lymphokine with apparent molecular size of 10 to 12 kilodaltons is secreted from helper T cell clones within hours after cross-linking their T cell antigen-MHC (major histocompatibility complex) receptors (T3-Ti). This lymphokine, termed interleukin-4A (IL-4A), stimulates resting lymphocytes by binding to a surface component (or components) of the alternative T11 pathway and subsequently by inducing interleukin-2 (IL-2) receptors. The activation process is neither dependent on antigen specificities of the recruited population or the presence of macrophages. It appears, therefore, that IL-4A is a mediator involved in amplifying the T cell immune response.     

The T cell receptor

The primary structure of T cell receptor proteins and genes is well understood. Immunologists are now trying to understand the properties of these interesting molecules. Evidence suggests that T cell alpha beta receptors recognize a complex of an antigen-derived peptide bound to one of the cell-surface products of the major histocompatibility complex (MHC) genes. It is likely that alpha beta receptors and MHC proteins have coevolved to have some affinity for each other. During T cell development in the thymus, cells bearing self-reactive receptors are deleted by the mechanisms of tolerance, and cells are preferentially allowed to mature if they bear receptors that will be able to recognize antigen plus self-MHC after they have become full-fledged T cells. Some explanations for these phenomena have been tested, but no satisfactory theory can yet be proposed to account for them.     

离子束介导大豆DNA导入小麦当代(T_1)和二代(T_2)的变异分析

T1代收获2241株,选出蛋白质含量>15%的单株占样本总数的2.76%,湿面筋含量>35%的单株占样本总数的0.54%。对T2代籽粒蛋白质、湿面筋含量分析发现,T2代的高蛋白植株明显增加。T2代湿面筋含量>35%的优良单株占样本总数的4.36%。表明离子束介导大豆DNA对小麦的蛋白质、湿面筋含量的提高有明显的效果。24h DNA温育有可能是离子束介导大豆DNA导入小麦的理想条件。     

Control of experimental autoimmune encephalomyelitis by T cells responding to activated T cells

T cell vaccination against experimental autoimmune disease is herein shown to be mediated in part by anti-ergotypic T cells, T cells that recognize and respond to the state of activation of other T cells. The anti-ergotypic response thus combines with the previously shown anti-idiotypic T cell response to regulate autoimmunity.     

Downregulation of L3T4+ cytotoxic T lymphocytes by interleukin-2

Proliferation of activated cytotoxic T lymphocytes (CTLs) that recognize foreign histocompatibility antigens is induced by interleukin-2, a potent immunoregulatory molecule originally described as T cell growth factor. Interleukin-2 (IL-2) is widely used to isolate and induce clonal expansion of CTLs for functional studies in vitro and in vivo. However, in studies with CTLs specific for class I and class II histocompatibility antigens, IL-2 rapidly downregulated the lytic activity of some class II-specific CTLs in a time- and dose-dependent manner. Lytic activity of L3T4+ CTLs specific for the murine class II antigen I-Ek was repeatedly up- and downregulated in vitro by alternate exposure to specific (alloantigen) and nonspecific (recombinant IL-2) signals, respectively. These results demonstrate that some CTLs modulate their functional property (cytolysis) while undergoing IL-2-driven cell proliferation without loss of antigen specificity or ability to revert to a lytic phenotype.     

Self-nonself discrimination by T cells

The alpha beta T cell receptor (TCR) recognizes antigens that are presented by major histocompatibility complex (MHC)-encoded cell surface molecules by binding to both the antigen and the MHC molecules. Discrimination of self from nonself antigens and MHC molecules is achieved by negative and positive selection of T cells in the thymus: potentially harmful T cells with receptors that bind to self antigens plus self MHC molecules are deleted before they can mount immune responses. In contrast, the maturation of useful T cells with receptors that bind foreign antigens plus self MHC molecules requires the binding of their receptor to MHC molecules on thymic epithelium in the absence of foreign antigen. The binding of the TCR to either class I or class II MHC molecules directs differentiation of the selected cells into either CD4-8+ (killer) or CD4+8- (helper) T cells, respectively.