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41.
随着网络教育的发展,接受网络教育和考试认证的人越来越多,在线考试正在得以迅速发展.本文简要介绍在线系统工作原理和系统配置.  相似文献   
42.
以郑单958和豫单606为试验材料,采用盆栽试验方法,探索不同硼肥用量对玉米产量及生长发育的影响。结果表明,施用适量硼肥可促进玉米生长发育,显著提高叶面积指数,使植株干物质积累量增加,同时硼肥能够促进干物质向果穗运输。施用硼肥能够促进玉米穗分化,使雌雄间隔期缩短,显著提高花丝数和花丝生长速率,进而增加穗粒数。施用硼肥显著提高玉米产量,且不同用量对其影响不同,3.33 mg/kg土壤硼肥处理的效果最为显著,郑单958和豫单606分别较不施硼肥处理增产14.3%和17.4%;施用量为13.3 mg/kg时郑单958增产3.5%;豫单606产生中毒症状,产量较对照降低4.4%。  相似文献   
43.
农业气象自动化观测系统国家级平台是依托中国气象局组织的农业气象自动化观测试点工作而设计开发,平台的搭建采用B/S架构实现多级用户、跨平台登录,采用XML及JSON等数据传输格式实现国家级、省级、台站级用户信息交互,实现农业气象观测XML数据传输状态的监控、台站端设备状态的评估以及数据内容的实时查询。  相似文献   
44.
By the infection of Brucella virulent strain and attenuated strain in mice macrophage RAW264.7,the assay was aimed to explore the relationship between NF-κB signaling pathways and Brucella virulent strain and attenuated strain in intracellular survival.Use different MOI Brucella (2308,RB51,16M and M5) to infect mice macrophage RAW264.7,after 0,4,8 and 24 h infected,cracking cell and collecting supernatant,we detected the effect of Brucella on activation of NF-κB signaling pathway by Western blotting.Different concentrations of NF-κB signaling pathway inhibitor were incubated with mice macrophage RAW264.7,with different multiplicities of infection (MOI) of Brucella infecting cells,ELISA kits to detect the expressions of TNF-α,IL-1β and IL-6 cytokine;At the same time,count the number of intracellular bacteria of CFU.The results showed that rough cattle Brucella strains RB51 could strongly activate NF-κB signaling pathway,smooth cattle Brucella strains 2308 was weak in the activation;At the same time,the activation of NF-κB signaling pathway was concentration dependent.When the MOI was 80,infection time was 8 h,NF-κB activation degrees of rough cattle Brucella strains RB51 and smooth cattle Brucella strains 2308 were the strongest,and this pathway was involved in producing TNF-α and IL-6;NF-κB signaling pathway inhibitor BAY11-7082 affected Brucella intracellular survival.So rough cattle Brucella strains RB51 intracellular survival and NF-κB signaling pathway activity were closely related.The results laid the foundation for the further study of Brucella intracellular pathogenesis,also provided scientific basis for the research of new drugs to Brucella,and prevention and treatment of brucellosis.  相似文献   
45.
【目的】研究反刍动物蛙皮素样肽家族多肽及其受体的保守性。为不同动物,特别是反刍动物这2种蛙皮素样多肽及其受体蛋白抗原设计和活性多肽筛选等研究提供参考。【方法】采用生物信息分析学的方法,通过UniProt数据库比较牛的蛙皮素样肽家族胃泌素释放肽(Gastrin-releasing peptide, GRP)和神经介素B(Neuromedin B, NMB)2种多肽及其特异性受体GRP-R和NMB-R与其他动物氨基酸序列的差异性。【结果】13种动物成熟GRP多肽C-端的8个氨基酸序列完全相同,牛GRP氨基酸序列与绵羊、猪和豚鼠最高,分别为88.7%、77.8%和77.8%,与其他动物相似性低于74.1%。10种动物成熟NMB多肽C-端10个氨基酸序列完全相同。牛GRP-R与狗、马和猪等相似性最高,分别为96.1%、94.3%和94.0%,牛NMB-R与猪、人和马相似性最高,分别为92.3%、91.5%和91.0%;牛GRP-R与NMB-R相似性仅为62.2%。【结论】GRP和NMB的C-端氨基酸序列在不同动物之间均具有高度的保守性,而N-端为变化区域,且GRP-R和NMB-R氨基酸序列在动物之间保守性较高。  相似文献   
46.
47.
膜联蛋白是一类有效的内源性调节蛋白,在Ca2+存在的条件下与膜磷脂结合,参与细胞活动的多种功能,其与肿瘤发生、自身免疫性疾病、病毒和寄生虫感染等密切相关。作为膜联蛋白家族成员Annexin B1具有独特的氨基酸残基结构,与不同种属的寄生虫入侵特异性宿主密切相关。本文主要阐述了膜联蛋白的种类及膜联蛋白B1在猪囊尾蚴感染宿主机体过程中免疫逃避的作用,旨在探索其猪囊尾蚴感染的免疫逃避机制。深入对膜联蛋白B1和囊尾蚴之间相互关系的进一步了解,以及膜联蛋白B1在寄生虫免疫中更深入的研究,对寄生虫免疫逃避的生物学意义和寄生虫病诊断治疗提供了相关的策略。  相似文献   
48.
Farmers' participatory field trials were conducted at Madhuban, and Taraori, the two participatory experimental sites/locations of the Cereal Systems Initiative for South Asia (CSISA), a collaborative project of IRRI and CIMMYT in Karnal district of Haryana, India, during Kharif (wet season) 2010 and 2011. This research aimed to evaluate preemergence (PRE) and postemergence (POST) herbicides for providing feasible and economically viable weed management options to farmers for predominant scented rice varieties. Treatments with pendimethalin PRE fb bispyribac-sodium + azimsulfuron POST had lower weed biomass at 45 days after sowing (DAS). At Madhuban, highest grain yield of scented basmati rice (3.43 t ha−1) was recorded with the sequential application of pendimethalin PRE fb bispyribac-sodium + azimsulfuron POST. However, at Taraori, yields were similar with pendimethalin or oxadiargyl PRE fb bispyribac-sodium and/or azimsulfuron POST. Applying oxadiargyl by mixing with sand onto flooded field was less effective than spray applications in non-flooded field. The benefit-cost ratio of rice crop was higher with herbicide treatments at both sites as compared with the non-treated weed-free check except single PRE and POST applications and sequential application of oxadiargyl PRE fb oxadiargyl PRE. In a separate experiment conducted at Nagla and Taraori sites, scented rice cultivars' ('CSR 30′ and 'Pusa 1121′) tolerance to three rates of azimsulfuron (15, 25, and 35 g ai ha−1) was evaluated over two years (2010 and 2011). CSR 30 (superfine, scented) was more sensitive to higher rates (35 g ai ha−1) of azimsulfuron as compared to Pusa 1121 (fine, scented). Crop injuries were 8 and 28% in case of CSR 30; 5 and 15% in Pusa 1121 when applied with azimsulfuron 25 and 35 g ai ha−1, respectively. Azimsulfuron applied at 35 g ai ha−1 reduced yield in both cultivars but in CSR 30 yield reduction was twofold (11.5%) as that of Pusa 1121 (5.2%).  相似文献   
49.
Activators of sesquiterpene synthase (STS) gene expression and sesquiterpene production in Piper betle L. were examined using quantitative real time PCR and gas chromatography mass spectrometry methods, and the allelopathic activity of untreated and Fusarium solani-treated betel extracts was tested on seed germination and on the shoot and root growth of Thai rice variety PSL2 (Oryza sativa cv. Phitsanulok 2) and three dominant paddy weeds (Eclipta prostrata, Echinochloa crus-galli and Chloris barbata). The results demonstrated that F. solani dramatically upregulated STS expression and productions of β-cubebene, β-caryophyllene and germacrene D sesquiterpene when compared with the untreated control, and that betel extracts had a greater inhibitory effect on weeds than on rice. The effects were more clearly detected on seed germination and root growth than on shoot growth, and they were found to be dose-dependent. It is also noted that F. solani-treated extract had stronger effects than the untreated extract. The species most sensitive to the allelopathic effects was C. barbata, germination of which was completely inhibited even at a dose of 0.1 mg/mL untreated extract. With regards to rice, although betel extract at 1.0 mg/mL showed no inhibition on germination, it affected the elongation of rice roots, in addition to those of the tested weeds. The obtained data suggested that F. solani has potential as an activator of sesquiterpene allelochemical production via STS expression, the latter leading to the treated betel extract having a stronger phytotoxic effect. These results were beneficial in the promotion of natural herbicide production using biotechnology.  相似文献   
50.
基于XML的科研管理信息系统研究   总被引:1,自引:0,他引:1  
该文在分析农业科研单位科研管理现状的基础上,提出了一种基于XML技术的科研管理信息系统,并进一步介绍了系统采用的B/C/S结构模型,阐述了系统的功能模块和系统实现的部分关键技术。得出该系统能降低对客户端的要求,减少系统的通讯量,使得数据的呈现、交互更加容易,从而提高了科研管理工作的效率。  相似文献   
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