漂浮育苗剪叶传播烟草丛顶病风险研究

为了评估漂浮育苗剪叶传播烟草从顶病的风险,以剪刀剪病叶后再剪苗和剪刀蘸取病烟汁液后再剪苗2种剪叶方法研究了漂浮育苗剪叶对烟草丛顶病和烟草普通花叶病的传播效果.调查数据显示,2种剪叶方法均不能传播烟草丛顶病,但能传播烟草普通花叶病,其平均发病率分别为36.67%和63.33%.实验结果表明,漂浮育苗剪叶不易传播烟草丛顶病,但易于传播烟草普通花叶病.     

广东烟草花叶病毒株系研究

烟草花叶病毒（TMV）引起的烟草花叶病在广东不同的烟草主产区存在着症状的差异。从广东梅州和南雄烟区采集的138个TMV标样中,选取6个不同症状的分离物作为研究对象,发现它们在不同种属寄主和不同烟草品种上表现明显的TMV普通株特征症状,虽然在某些寄主上其症状也有一些差异,但未能反映株系间的差异。这6个分离物具有几乎相同的病毒粒体形态、电泳迁移率、钝化温度以及紫外吸收特征。经琼脂双扩散法和间接ELISA法的血清学反应,表明它们具较强的血清学关系。因而它们有很强的同源性。经病毒粒体外壳蛋白的氨基酸分析,在氨基酸总数上,分离物GD1和GD3各有156个氨基酸．GD2和GD4各有159个,GD5和GD6分别有158和157个氨基酸。上述分析试验结果初步表明,在广东不同烟草主产区引起的症状有所差异的6个分离物均属IMV普通株。     

Floating period of Sargassacean thalli estimated by the change in density

The density (fresh weight/volume) of the detached thalli of four sargassacean species (Myagropsis myagroides, Sargassum horneri, S. patens, S. siliquastrum) was measured weekly to determine their floating period. Thalli of the four species were collected with respect to the difference in their reproductive stage, and their floating abilities at different stages were determined. Floating thallus was ballasted with pre-weighed leads until the final addition of a weight caused sinking. The density and floating period of sargassacean thalli were dependent on the species and the specimens’ reproductive stage. The floating period of thalli detached before maturation was estimated to be between 4 and 14 weeks. However, thalli detached during maturation had a floating period of between 1 and 8 weeks, and those detached after maturation sank within 2 weeks. Sargassum horneri had the lowest density and the longest floating period among the four species investigated and this may explain the high abundance of S. horneri in floating seaweeds observed in the Sea of Japan.     

嘧肽霉素影响烟草花叶病毒RNA蓄积量的研究

嘧肽霉素是新报道的由土壤中分离筛选出来的不吸水链霉菌辽宁变种(Streptomyces achygroscopicus var.liaoningensis)产生的,其有效成分是胞嘧啶核苷肽类化合物,已获得农药临时登记,该药剂对烟草花叶病毒(Tobacco mosaic virus,TMV)等多种病毒病害具有很好的防治效果。定量竞争PCR(Quantitative competitive PCR,QCPCR)是一种定量检测细胞因子较为精确的方法,其实质是待测核酸(DNA或RNA)与内参模板一起竞争参与PCR反应,并通过电泳将扩增产物在凝胶上明显的分开,从而进一步进行定性或定量分析。     

Studies on the Resistance Mediated by Three Mutants of TMV 54K Protein Gene

Three deletion mutants of tobacco mosaic virus (TMV) 54-kD putative replicase gene (54K) were obtained by PCR, and cloned into plant expression vector p208, then transformed into Nicotiana tabacum L. cv. SR1 by Agrobacterium tumefaciens (Smith et Townsend) Conn Ti plasmid-mediated transformation. All the transgenic plants with the N-terminal deletion mutant, the C-terminal deletion mutant and the only 261 nucleotides region from the central part of the 54K ORF showed significant resistance against TMV.      

Floating seaweed and the influences of temperature, grazing and clump size on raft longevity — A microcosm study

Laboratory experiments were conducted to evaluate the longevity, and consequently also the rafting capacity of the brown seaweeds Fucus vesiculosus and Ascophyllum nodosum. The seaweed degradation process and the activity of the grazer Idotea baltica were strongly influenced by temperature: only at 5 °C, the seaweed growth exceeded the weight loss. At higher temperatures, seaweed fragments sank quickly (within 100 days at temperatures higher than 15 °C). This process was significantly accelerated in the presence of I. baltica, resulting in a decrease of raft longevity of 60-70%. At a constant temperature of 15 °C and in the absence of grazers, fragments of A. nodosum floated longer (mean 45 weeks) than fragments of F. vesiculosus (mean 15 weeks). The results indicate that floating seaweeds have the potential to stay afloat for a long time, but that their longevity is temperature-dependent and can be strongly reduced by grazing activity of associated herbivores.     

情绪调节自我效能感对慢性阻塞性肺疾病患者治疗的影响

目的:本研究探讨心理干预对患者情绪调节自我效能感的影响,分析情绪调节自我效能感对慢性阻塞性肺疾病患者治疗和康复的影响.方法:1)实验分为干预组(实验组)和非干预组(对照).2)情绪调节自我效能感量表评定患者干预前后的情绪调节自我效能感.3)对心理干预组进行随访,使用理性情绪化疗法、支持疗法、情绪宣泄法、康复指导及疾病意外应对指导进行干预.结果:1)为其1年心理干预有效降低疾病复发率、住院时间和住院频率.但对急性发作治疗期的治疗影响不显著.2)心理干预有效提高患者的情绪调节自我效能感.结论:心理干预有效提高患者的情绪调节自我效能感,促进缓解期的慢性阻塞性肺疾病患者的康复,并有效降低复发率.     

一些抗植物病毒剂对烟草花叶病毒衣壳蛋白体外聚合过程的影响

一些抗植物病毒剂对烟草花叶病毒衣壳蛋白体外聚合过程的影响江山,郭雪柳,韩熹莱（北京农业大学基础科技学院,北京１０００９４）关键词抗植物病毒剂,烟草花叶病毒,病毒衣壳蛋白,体外聚合研究表明,有些植物病毒的核酸对寄主植物的侵染活性只有装配完整的病毒颗粒的...     

俯卧位在新生儿蓝光治疗中的应用

目的：解决新生儿在接受蓝光治疗时,出现哭闹不安、大量溢奶情况,提高蓝光治疗效果,减轻护理工作量。方法：将2010年至2011年收治我科的80例高胆红素血症患儿,随机分为观察组40例和对照纽40例,患儿在性别、日龄、体重、黄疸严重程度上均无显著性差异,在接受首次蓝光照射治疗的24小时过程中,对比哭闹及溢奶症状发生率、治疗后经皮测黄疸指数。结果：两组的哭闹及溢奶症状发生率、治疗后经皮测黄疸指数有显著性差异,P〈0．05。结论：新生儿俯卧位较仰卧位能提高蓝光治疗效果,提倡俯卧位应用于新生儿蓝光治疗。     

烟草抗黑胫病突变体的细胞筛选

经实验我们成功地建立了在细胞水平上筛选烟草抗黑胫病突变体的筛选体系。该体系的主要内容为:γ-射线500—2000拉德诱变高度感病品种的花药后用50—80％的黑胫病菌粗毒素为选择压力,筛选出抗毒素花粉植株,用离体叶片法测定选出抗病植株,再从后代鉴定中选出抗病性能够稳定遗传的突变系。γ-射线及高浓度毒素处理均能得到抗病植株。选自感病品种的花粉植株中约有9—50％是真正抗病的。这些抗病植株中有一部分的抗病性能够稳定遗传。用该法已从感病优质品种小黄金1025及乔庄黑苗中选出6个突变系。并自N.C.628(抗)×小黄金1025(感)及N.C.628(抗)×庆胜2号(感)的F_1花粉植株中选出4个抗病系。所有的抗病系经3—4代后均表现出稳定抗性。其中一个突变体(R400)的抗性似由不完全显性多基因控制。