分子标记辅助改良培矮64S稻瘟病抗性

为提高我国大面积应用的两系光温敏不育系培矮64S的稻瘟抗性,本研究通过杂交转育与分子标记选择相结合的途径,利用RM3330与RM262为标记,将Pi25与Pi-d(t)基因成功聚合于培矮64S中,经抗性、不育性、综合农艺性状评价,获得了5个基因型纯合且农艺性状稳定的F8代抗性改良候选不育系。抗性鉴定结果显示,抗性改良候选不育系及其抗性组合的叶瘟病情指数平均降幅为18.78%和23.24%,穗颈瘟病情指数平均降幅为18.58%和58.45%,抗性提高幅度极显著。育性观测结果表明抗性改良候选不育系不育度都在99.5%以上,柱头外露降低5.64%,包颈粒率降低8.55%。经济性状调查结果显示不育系除穗粒数下降、有效穗增加外,其余经济性状变化不明显;试配的杂交组合平均理论产量和实际产量比对照提高16.22%和6.89%,增产极显著。这些结果表明,通过Pi25与Pi-d(t)基因的导入显著提高了培矮64S稻瘟病抗性,获得了实用的光温敏不育系新材料。     

Insecticide detoxification indicator strains as tools for enhancing chemical discovery screens

BACKGROUND: Insecticide discovery screens carried out on whole organisms screen for potency resulting from chemical activity at the target site. However, many potentially insecticidal compounds are naturally detoxified in vivo and do not make it to the target site. It is hypothesised that insect strains with their xenobiotic detoxification machinery compromised could be used to identify such compounds that normally fail to show up in screens; these compounds could then be more rationally designed to increase their bioavailability. This strategy was tested with transgenic Drosophila lines with altered expression of Cyp6g1 and Dhr96. RESULTS: It was observed that Cyp6g1 knockdown transgenic lines have increased susceptibility to the test compound imidacloprid, while Dhr96 knockdown transgenic lines are resistant. Evidence was found for a systemic response to xenobiotic exposure, uncovered by piperonyl butoxide treatment and by gene expression profiling. Sex-specific gene expression regulated by DHR96 was also observed. CONCLUSION: The results confirm that this approach to chemical discovery could identify compounds that escape traditional screens. The complexity of the system means that a panel of single and multiple gene knockdown transgenic lines may be required. Copyright © 2011 Society of Chemical Industry     

1α，25-二羟维生素D3对大鼠成骨细胞增殖分化及周期的影响

在SD大鼠成骨细胞（Osteoblast,OB）体外培养体系中添加不同浓度1α,25-二羟维生素D3（0、10^-9、10^-8、10^-7mol／L）,作用24、48、72h,测定OB增殖率、碱性磷酸酶（ALP）活性,作用48h流式细胞仪测定0B周期。结果显示,10^-9mol／L 1α,25-二羟维生素D3作用24、48、72h均促进oB增殖（P〈0.05或P〈0.01）,抑制ALP活性（P〈0.01）;10^-8、10^-7mol／L作用24、48h,OB增殖率与对照组差异不显著（P〉0.05）,但24h时ALP活性均明显升高（P〈0.05或P〈0.01）,48h则抑制了ALP活性并使OB滞留在G2／M期（P〈0.05或P〈0.01）;72h时10^-7mol／L组OB增殖率极显著低于其余各组（P〈0.01）,并使ALP活性升高（P〈0.01）。表明低浓度1α,25-二羟维生素D3能促进OB增殖,抑制其分化;高浓度1α,25-二羟维生素D3能抑制OB增殖,促进其分化,并使细胞滞留在G2／M期。     

Indirect Utilization of Hefeng 25 and Breeding of ‘Hefeng＇ Soybean Varieties

为了研究优秀种质资源的利用方式,以合丰25育成的品种（系）作母本,与不同结英习性的大豆杂交,成功育成7个合丰号大豆品种,合丰40、合丰42、合丰43、合丰55、合丰56、舍农60、舍农62,这些品种对合丰号大豆的推广应用起到了重要的作用。同时合丰25的间接利用效果显著。     

基于本体的玉米领域知识表示构建研究

传统的人工智能采用不同的建模方法、开发工具进行知识表示,使得各种知识表示之间缺乏互操作性,本体的引入解决了这一问题。对基于本体的知识表示方法进行了探索,对玉米领域知识本体进行了构建。结果表明,本体可有效地解决复杂知识间表达的异构问题,使计算机对信息的理解升至为语义层次,利于玉米智能系统的研制。     

饮水添加25-OH-D3对肉仔鸡生产性能的影响

随机设计，饮水添加不同剂量的25-OH—D3研究对肉仔鸡生产性能的影响。结果表明：①饮水添加18μg／kg25--OH—D3，可提高肉鸡采食量，提高肉鸡增重，明显降低料肉比，差异显著（P〈0．05）；②饮水添加18μg/kg25-OH-D3，各项屠宰指标均高于对照组且差异显著（P〈0．05）；③饮水添加18μg／kg 25-OH—D3，可获得最高经济效益。     

Abnormal synaptic protein expression in two Arabian horses with equine degenerative myeloencephalopathy

Numerous swollen neurons and multiple dystrophic axons were observed in the gracillis and cuneatus nuclei of two male Arabian horses, aged six and 12 months of age, with equine degenerative myeloencephalopathy. Swollen neurons and dystrophic axons showed synaptophysin, synaptosomal-associated protein of 25 kDa, syntaxin-1 and alpha-synuclein immunoreactivity. Moreover, dystrophic axons were strongly immunopositive against the ubiquitin protein and against the anti-phosphorylated 200 kDa neurofilament protein. Abnormal expression of integral synaptic vesicle, synaptic vesicle-associated presynaptic plasma membrane and cytosolic proteins, which participate in the trafficking, docking and fusion of the synaptic vesicle to the plasma membrane, suggest that severe disruption of axonal transport plays a crucial role in the pathogenesis of dystrophic axons in equine degenerative myeloencephalopathy (EDM).     

Association between development of CD4+CD25+ regulatory T cells and thymus CD4-CD25+ cells

AIM: To explore the correlation between development of CD4⁺CD25⁺ regulatory T cells (CD4⁺CD25⁺ Tr) and thymus CD4^-CD25⁺ cells. METHODS: The ratios of CD4⁺CD25⁺ regulatory T cells to CD4+ T cells in thymus, spleen, lymph node and peripheral blood of mice from birth to mature and also the ratios of CD4^-CD25⁺ cells to CD4^- T cells in thymus were measured by flow cytometry. Purified CD4⁺CD25⁺ T cells and CD4⁺CD25^- T cells were labeled with CFDA-SE, and then stimulated with various kinds of stimulators. RESULTS: The percentages of CD4⁺CD25⁺ Tr in mouse spleen, lymph nodes and peripheral blood increased gradually, but not in thymus, from day one to week 10 of the age with rapid rising from day one to week 1. The percentages of CD4^-CD25⁺ cells in mouse thymus were quite high on day one after birth, and decreased rapidly from day one to week 1. Both CD4⁺CD25⁺ Tr and CD4⁺CD25^- T cells showed no proliferation in response to ConA, while CD4⁺CD25⁺ Tr showed a transient enlargement of cell size. Both CD4⁺CD25⁺ Tr and CD4⁺CD25^- T cells underwent proliferation in response to PDB plus ionomycin. CD4⁺CD25^- T cells, but not CD4⁺CD25⁺ Tr, showed a proliferative response to the stimulation of coated anti-CD3 plus soluble anti-CD28 antibody, however, CD4⁺CD25⁺ Tr showed significant proliferation and CD4⁺CD25^- T cells showed a stronger response in addition of high dose of IL-2. CONCLUSION: The thymus CD4^-CD25⁺ cells are probably the precursor of CD4⁺CD25⁺ Tr during cell development.     

口蹄疫感染性克隆疫苗的发展前景

口蹄疫是一种严重威胁畜牧业发展的重要传染病,目前世界上许多国家和地区都有该病的流行与发生。开展新型口蹄疫疫苗的研究一直是口蹄疫防制技术的一项重要内容。鉴于传统疫苗所存在的诸多缺点,人们先后研制开发了口蹄疫的第二代基因工程苗和第三代基因疫苗,这些新型疫苗都具有一定的优越性,显示出进一步发展的潜力。文章着重讨论了在感染性cDNA的基础上所构建的一类新型基因疫苗-感染性克隆疫苗及其发展前景。感染性克隆疫苗不仅继承了以往基因疫苗的许多优点,而且克服了其表达量低,免疫效果不理想的缺点,为新型疫苗的研制提供了一种新的思路。     

转基因大豆中外源基因g10evo-epsps的qPCR检测方法的建立和验证

耐除草剂基因g10evo-epsps在我国转基因农作物研发中常常被用作目标性状基因或筛选标记基因,因此可作为转基因成分检测的重要筛查基因,但目前缺少相应的检测方法.本研究旨在建立g10evo-epsps基因特异性的实时荧光定量PCR(qPCR)检测方法,从而为转基因大豆的监测提供一种稳定可靠的方法体系.本研究基于转基因...