养殖场的选址和布局

养殖场的选址和布局选址是养殖环节的重要前提和基础性工作,合理的选址与布局为家畜和管理人员创造良好生产和生活环境,合理的利用自然资源和社会资源,避免了不必要的损失.     

地膜玉米栽培及病虫害防治要点分析

首先从分做好播前准备、品种选择、精细整地、铺膜播种、田间管理和收获6个方面阐述了地膜玉米高产栽培技术,然后对地膜玉米病虫害防治进行了简单的探讨。     

Quantitative structure-activity relationships of monoterpenoid binding activities to the housefly GABA receptor

BACKGROUND: Monoterpenoids are a large group of plant secondary metabolites. Many of these naturally occurring compounds have shown good insecticidal potency on pest insects. Previous studies in this laboratory have indicated that some monoterpenoids have positive modulatory effects on insect GABA receptors. In this study, the key properties of monoterpenoids involved in monoterpenoid binding activity at the housefly GABA receptor were determined by developing quantitative structure‐activity relationship (QSAR) models, and the relationship between the toxicities of these monoterpenoids and their GABA receptor binding activities was evaluated. RESULTS: Two QSAR models were determined for nine monoterpenoids showing significant effects on [³H]‐TBOB binding and for nine p‐menthane analogs with at least one oxygen atom attached to the ring. The Mulliken charges on certain carbon atoms, the log P value and the total energy showed significant relationships with binding activities to the housefly GABA receptor in these two QSAR models. CONCLUSIONS: From the QSAR models, some chemical and structural parameters, including the electronic properties, hydrophobicity and stability of monoterpenoid molecules, were suggested to be strongly involved in binding activities to the housefly GABA receptor. These findings will help to understand the mode of action of these natural insecticides, and provide guidance to predict more monoterpenoid insecticides. Copyright © 2012 Society of Chemical Industry     

湖北房县烟区土壤重金属含量状况及其与土壤肥力的关系

以湖北房县烟区186份植烟土壤样品为供试材料,研究了植烟土壤重金属含量与土壤肥力的关系。试验结果表明,(1)湖北房县烟区植烟土壤重金属含量状况符合无公害农产品产地环境条件的要求。(2)湖北房县烟区大部分植烟土壤养分变异系数较小,肥力较为均匀。(3)在一定范围内,pH值处于中性偏酸(6.0～7.0)时,土壤的重金属含量相对较低,当pH<6.0时,重金属含量较高;重金属含量与阳离子代换量(CEC)的关系明显,随着CEC值的增加,重金属含量增加;除As元素外,碱解氮的含量越高,重金属的含量越高;随着速效磷和速效钾含量的增加,重金属含量均增加;除重金属As变化不明显外,其他重金属含量均与有机质含量的关系明显,随着有机质含量的增加,重金属含量增加。     

新疆永久基本农田建设思考

为提高新疆永久基本农田建设水平,基于新疆基本农田保护现状,从保护中暴露出的生态环境脆弱与化肥过度使用、基本农田保护区划定要求不明确、基本农田保护区规模经营水平不高、基本农田保护措施不到位以及激励机制不健全等问题入手,对在新疆划定和建设永久基本农田进行探究,提出严格控制化肥施用量、完善永久基本农田保护区规划、加大对永久基本农田的资金投入、建立基本农田保护长效机制等对策措施。     

影响转基因绵羊胚胎移植受胎率的因素

为了提高并稳定转基因胚胎移植受胎率,对可能影响受胎率的供受体同期化程度、移植胚胎数量、受体处理方式、胚胎发育速度、受体注射黄体酮、供体作受体等6个方面进行研究。结果表明,(1)供受体发情时间差在±12h以内,不影响受胎率(P>0.05);(2)每只受体移植2～3枚转基因胚胎的受胎率极显著高于移植1枚的受胎率(P<0.01);(3)在繁殖季节里,受体采用自然发情、肌肉注射PGF2α、肌肉注射PMSG+PGF2α等方式,三者受胎率间差异不显著(P>0.05);(4)发育迟缓的胚胎移植后,受胎率显著低于正常发育胚胎的受胎率(P<0.01);(5)移植后的受体注射2mg黄体酮,不能提高受胎率(P>0.05);(6)供体当作受体使用,不影响受胎率(P>0.05)。     

北美红栎扦插繁殖技术的研究

为了研究北美红栎的扦插繁殖技术,选取一年生与当年生半木质化北美红栎枝条对其进行硬、嫩枝扦插试验。选取不同部位以及不同直径的枝条作为插穗,通过不同生根剂、不同浓度处理、不同基质和不同时间扦插的试验,研究插穗生根的效果。结果表明,北美红栎嫩枝扦插生根效果优于硬枝扦插,以ABT1 600 mg·L-1处理嫩枝插穗,生根效果最好,生根率、最长根长及平均根数分别为38.3%、3.24 cm和1.7条;选择母株当年生枝条中上部做最佳插穗;插穗最佳直径为4～6 mm;珍珠岩与泥炭土体积比1:1的混合基质为最佳基质,在8月份室外扦插效果为佳,生根率、最长根长及平均根数分别为53.3%、3.35 cm和1.5条。     

Peri-sciatic administration of recombinant rat TNF-α induces pathological pain

AIM: To test the possibility that TNF-α can induce the display of nociceptive behaviors in rats without any injury. METHODS: The induction of changes in 50% paw withdrawal threshold and paw withdrawal latency by peri-sciatic administration of recombinant rat TNF-α (rrTNF) was determined with the methods of behavioral tests. PDTC (a NF-κB inhibitor) was also intrathecally delivered before or after the administration of rrTNF. RESULTS: We found that peri-sciatic administration of rrTNF at the concentrations of 10, 100, and 1 000 ng/L (daily for 2 d) induced mechanical allodynia and thermal hyperalgesia in bilateral hindpaws, lasting for around 20 d. Intrathecal administration of PDTC 30 min before each peri-scitic administration of rrTNF completely prevented the decrease in bilateral thresholds, and delayed the decrease of paw withdrawal latencies. In contrast, the same dose of PDTC had no effect on mechanical allodynia when applied intrathecally 6 d after the first administration of rrTNF, while inhibited thermal hyperalgesia for about 7 d. CONCLUSION: Without any nerve injury, peri-sciatic administration of recombinant rat TNF-α at low doses produces mechanical allodynia and thermal hyperalgesia in bilateral hindpaws. NF-κB pathway may play different roles in mechanical allodynia and thermal hyperalgesia.     

中原地区肉羊生产系统的特征分析

 依据产区的生态地理特征，将河南省的地方绵山羊品种划分为不同的生态型，比较了平原型与丘陵型绵羊、平原型与山地型山羊的种质特征；论述了中原地区肉羊生产系统的结构功能特征，阐明了其进化发展过程；指出了中原地区肉羊生产系统的地位和需要探讨的问题。     

泵站多功能压力集测仪

介绍了一种适用于泵站和电站的测量多种压力量和在压力管道的收缩段或弯头处利用差压法测量流量的智能仪器的原理和构成，可对双路测试通道进行巡测，能适应不同量程及与不同输出量的传感器配套使用，并且具有通讯及打印输出功能。