干旱胁迫下外源油菜素内酯对玉米幼苗光合作用和D1蛋白的调控效应

为了揭示干旱胁迫下外源油菜素内酯对玉米幼苗光合作用的保护机制,采用溶液培养的方法,以驻玉309为试验材料,研究外源油菜素内酯(BR)预处理及20% PEG-6000模拟干旱胁迫后玉米幼苗的生长参数、叶绿素含量、光合参数、叶绿素荧光参数及D1蛋白含量的变化。结果表明,与干旱胁迫处理(PEG)相比,BR+PEG处理的玉米苗株高增加45.87%,根长增加20.56%,总干物质积累增加8.01%,叶片相对含水量提高4.50%,叶绿素a含量增加26.32%,光合参数(Pn、Gs、Ci、Tr)分别提高9.57%,38.23%,30.19%,28.12%,光合系统Ⅱ(ΦPSⅡ)活性提高了20.48%,最大光化学效率提高了0.66%,光合系统Ⅱ绝对电子传递速率(ETR(Ⅱ)和相对电子传递速率r ETR(Ⅱ))分别提高20.40%和31.02%;D1蛋白含量增加37.34%(P0.05)。说明在干旱胁迫条件下叶片喷施BR可以改善玉米幼苗的生长发育,减缓光合系统的损伤,促进D1蛋白质的稳定,从而提高玉米幼苗对干旱胁迫的适应性。     

基于USB Key的水产品企业监管溯源系统设计与应用

根据目前水产品监管溯源系统中水产品企业身份认证存在的问题,设计了一种基于USB Key的水产品企业监管溯源系统。首先,分析了几种身份认证技术的方法,重点阐述了其优缺点;然后,设计了USB Key硬件电路关键部分、软件系统以及基于USB Key认证的水产品企业的认证流程,解决了水产品信息传输的安全性问题;最后,描述了基于USB Key的水产品企业监管模式在江苏省水产品企业认证与监管追溯平台中的应用。研究结果表明,该监管溯源系统便捷安全,稳定可靠,能实现产地准出、市场准入、企业资质认证、政府实时监控的水产品企业监管溯源体系。     

植物谷胱甘肽应答非生物胁迫的分子机制

谷胱甘肽(GSH)是一种普遍存在于植物中的抗氧化剂,在维持组织抗氧化防御和调节氧化还原敏感信号转导中起着关键作用。深入研究GSH在非生物胁迫中的作用,对从分子水平揭示植物GSH积累的调控机制具有重要意义。本研究从植物GSH代谢途径及其相关酶、GSH在植物应激反应中的调节、GSH参与植物激素代谢等方面进行综述,并对谷胱甘肽在植物生长发育、与其它信号通路间交互作用的研究前景进行展望,以期为植物谷胱甘肽代谢以及其在非生物胁迫方面的研究提供一定的理论参考。     

Analyses of monoclonal antibodies reacting with porcine wCD6: Results from the Second International Swine CD workshop

Among the 57 monoclonal antibodies analyzed within the T-cell group of the Second International Swine CD Workshop, one mAb fell within cluster T14a that included the CD6 standard a38b2 (No. 175). The new mAb MIL8 (No. 082) and a38b2 both precipitated from activated T-cells a 150 kDa monomeric protein. Staining patterns on the various cell types were similar. There was no inhibition of binding of either mAb to peripheral blood T-cells with the opposite mAb. The new mAb, MIL8, reacts with a separate epitope on porcine wCD6.     

小鼠基因内含子中CpG岛和几个转录调控元件分析

内含子在基因转录调控中的作用已多次被实验报道,然而对其参与调控的普遍性还缺乏足够的理论支持。本研究利用计算分析方法,对小鼠基因内含子中的CpG岛（CpGisland）、TATA框（TATAbox）、CAAT框（CAATbox）以及GC框（GCbox）等元件的出现频率进行分析。结果发现,分别有56.01%、57.16%、65.88%和41.86%的第一内含子具有CpG岛、TATA框、CAAT框以及GC框,而它们在其它内含子中的平均出现频率则分别为14.07%、45.24%、49.91%和13.19%。即使考虑到不同位置的内含子,这些元件在第一内含子中的出现频率也显著高于它们在其它任何位置内含子中的出现频率。由于CpG岛、TATA框、CAAT框以及GC框均与基因的转录调控有关,据此推测小鼠第一内含子在基因转录调控过程中具有潜在的重要性。本研究结果为内含子参与转录调控提供了更多的理论依据。     

水稻苗床增温剂及分蘖促进剂示范试验报告

通过对水稻施用苗床增温剂及分蘖促进剂试验示范研究,结果表明,增温剂及分蘖促进剂处理增加了水稻苗期的充实度,保证了壮苗,提高了后期的分蘖数与结实率。从产量结果上看,增温剂及分蘖促进剂处理较对照增产33.9 kg/667 m2,增产率为5.5%。     

Mesenchymal stem cell-induced CD8α+ Jagged2high CD11bhigh regulatory dendritic cells prevent and treat mouse aGVHD

AIM: To investigate the role of mesenchymal stem cell-induced regulatory dendritic cells (MSC-DCregs) in mouse acute graft-versus-host disease(aGVHD) model. METHODS: Bone marrow cells from BALB/c (H-2^d) mice were isolated and were induced to differentiate into DCs. The DCs were selected by flow cytometry, and after 10 d co-culture with MSCs, they were induced to be MSC-DCregs. Male 8-week-old C57BL/6 (H-2^b) mice were used as donor mice. The female 8-week-old BALB/c (H-2^d) mice, who had received 100 cm source-skin distance, 30 cm×30 cm radiation field, 700 cGy total body irradiation (TBI) pretreatment were used as recipient mice. The recipients were divided into 5 groups: control group, TBI group (injected with medium only), bone marrow transplantation group (injected with 1×10⁷ bone marrow cells), aGVHD group (injected with 1×10⁷ bone marrow cells and 1×10⁷ spleen cells), and MSC-DCregs group (injected with 1×10⁷ bone marrow cells, 1×10⁷ spleen cells and 1×10⁶ MSC-DCregs). The white blood cell count, recipients' chimerism, clinical evaluation of aGVHD, survival analysis and pathological changes were determined. RESULTS: Hematopoieic recovery was seen at 10 d after transplantation. The recipients' chimerism was parallel to the donors' at 30 d. The median survival time of the mice in aGVHD group and MSC-DCregs group was 27 d and 33 d, and the survival rates at 30 d were 20% and 100% (P<0.01), respectively. The clinical scores of the mice in MSC-DCregs group were lower than those in aGVHD group (P<0.01). Moreover, the pathological changes in the skin and liver of the mice in MSC-DCregs group were less serious than those in aGVHD group. CONCLUSION: The MSC-DCregs induce an aGVHD tolerance in vivo, and further research of its mechanism is still in great necessary.     

新奇的调控分子——microRNA

microRNA(miRNA)是一类内源性表达的在转录后基因调控中发挥重要作用的小分子非编码RNA。在动植物细胞中,miRNA通过翻译抑制和靶mRNA去稳定性来调控靶基因,从而调控生长、发育、分化、死亡等生物过程。综述了miRNA的发现、形成、特点及调控机制。     

几种调控措施对宽皮柑桔氮、磷、硼营养的影响

以15年生宽皮柑桔"华农本地早"为材料,研究了5种调控措施对其叶片氮、磷、硼含量的影响。结果表明,促花措施如施用PDJ-B和环割有提高非蛋白氮、降低蛋白氮含量的趋势,而抑花措施如施用GA3和6-BA则相反;促花措施降低了无机磷含量,提高了有机磷和全磷的含量,抑花措施一般与此相反;促花措施趋于提高了硼的含量,而抑花措施则相反。