浅谈互通立交连接部出入口设计     

赵竹莹 《林业科技情报》2012,(4):98-99

互通式立交端部设计是整个立交设计的重要部分,通过对端部出入口设计要点的分析研究,结合单、多车道出入口不同的设计要求,提出合理建议,以期更好的完善立交端部设计。  相似文献   

浅议工业厂房照明设计中的节能措施     

孙婷 《林业科技情报》2012,(2):94-95

伴随着中国经济的迅速发展,民用及工业建筑类的照明水平逐年提高。在照明设计中,应遵循在满足现代化工业厂房使用要求的同时,采用合理的技术措施达到节能、节约的设计理念,使热电厂的照明设计总体达到"安全可靠、经济适用、符合国情"的要求。  相似文献   

W/O微乳液体系中SA和MS清除·O_2~-的研究     

黄娟  马建华 《厦门水产学院学报》2010,(4):284-288

以水溶液体系作为对照,利用分光光度法研究了W/O型微乳液体系中水杨酸（SA）和水杨酸甲酯（MS）清除超氧阴离子自由基（·O2-）的性能.结果发现,在水浴时间为20min、pH值为8.20和邻苯三酚加入量适宜的情况下,W/O微乳液体系中SA、MS对·O2-的清除率分别可达72.92%、81.47%.微小的pH值变化会引起邻苯三酚自氧化速率的显著变化,电解质溶液对其也有明显的影响,但对SA、MS清除·O2-的能力影响不大.  相似文献   

大豆疫霉菌对大豆下胚轴侵染过程的细胞学研究   总被引：3，自引：0，他引：3  

左豫虎  康振生  黄丽丽  韩青梅 《植物病理学报》2005,35(3):235-241

 接种后1.5~24h,用光镜和电镜研究了2个大豆品种与大豆疫霉菌Ps411的亲和性和非亲和性互作。观察结果表明,大豆疫霉菌对大豆下胚轴的侵染过程可分为侵入前、侵入、皮层组织中的扩展和进入维管束组织4个连续阶段。大豆下胚轴接种后在25℃保湿培养,1.5h后游动孢子即形成休止孢并萌发产生附着孢,3h后侵入表皮细胞,6h后进入皮层组织,24h后进入维管束组织。病原菌主要以侵染菌丝直接侵入表皮,表皮细胞间隙是主要侵入部位。皮层细胞是病原菌定殖和发展的主要场所,胞间菌丝侵入皮层细胞并形成吸器。在菌丝与寄主细胞接触部位的寄主细胞壁与质膜之间常有胞壁沉积物的形成。在抗病品种上病菌的侵染事件与感病品种基本一致,但不能形成正常的吸器,胞壁沉积物明显多于感病品种,菌丝在寄主组织内的扩展明显受到抑制。利用β-1,3-葡聚糖免疫金标记单克隆抗体进行的免疫细胞化学的研究表明,胞壁沉积物内含有大量的β-1,3-葡聚糖,在大豆疫霉菌菌丝壁中也存在β-1,3-葡聚糖。以上结果表明,病原菌的侵染可诱导抗病寄主细胞内β-1,3-葡聚糖迅速的合成与积累、并形成胞壁沉积物,以抵御病菌的侵染与扩展。  相似文献   

螺旋毛壳ND35 β-1,3-葡聚糖酶的诱导、性质及其抑菌作用   总被引：8，自引：0，他引：8  

郭晓  高克祥  印敬明  白复芹  马迎新  于丹  刘晓光 《植物病理学报》2005,35(6):493-503

 以病原菌Rhizoctonia solani的细胞壁为诱导物,模拟毛壳菌自然的重寄生过程,研究了内生真菌螺旋毛壳(Chaetomium spirale) ND35 β-1,3-葡聚糖酶的产酶条件、性质,尤其是不同碳源的调控作用。结果表明,不同种类的真菌细胞壁及几丁质和昆布多糖,均可诱导产生β-1,3-葡聚糖酶,而作为分解代谢产物的葡萄糖则抑制产酶。经硫酸铵沉淀、DEAE-Sepharose阴离子交换层析及Phenyl-Sepharose疏水层析,并通过SDS-PAGE鉴定,纯化了一种分子量约为73 kDa的内切β-1,3-葡聚糖酶GLUC73。其最适反应温度为55℃,在40℃以下较稳定;最适pH值为5.5,在pH 5-9范围内均很稳定;酶活性受Hg²⁺、Fe³⁺、Zn²⁺、Mg²⁺等金属离子不同程度的抑制,Mn²⁺和Co²⁺对酶有激活作用;以昆布多糖为底物时,该酶的米氏常数K_m为0.412 mg·mL^-1,最大反直速度V_max为3.876 U·mL^-1。粗酶液同时具有β-1,3-葡聚糖酶和几丁质酶活性,离体抑菌试验表明,对苹果炭疽病菌(Glomerella cingulata)、杨树腐烂病菌(Valsa sordida)、苹果树腐烂病菌(Valsa mali)的菌丝生长和孢子萌发有明显的抑制作用。通过对β-1,3-葡聚糖进行免疫细胞化学标记和超微结构观察,间接证明了β-1,3-葡聚糖酶在螺旋毛壳重寄生过程中的作用。  相似文献   

Pain management in horses and farm animals     

Alexander Valverde  DVM  DVSc  DACVA    Cornelia I. Gunkel  Dr. med. vet.  MRCVS 《Journal of Veterinary Emergency and Critical Care》2005,15(4):295-307

Objective: This review discusses the different analgesic drugs and routes of administration used in large animals for acute pain management. General guidelines and doses are given to assist in choosing techniques that provide effective analgesia. Etiology: Noxious stimuli are perceived, recognized, and localized by specialized sensory systems located at spinal and supraspinal levels. Diagnosis: Localizing the source of the noxious stimulus as well as understanding the behavioral aspects and physiological changes that result from such insult is important to adequately diagnose and treat pain. Pain assessment is far from being definite and objective; not only are there species differences, but also individual variation. In addition, the behavioral and physiological manifestations vary with the acute or chronic nature of pain. Therapy: Pain management should include (1) selecting drugs that better control the type of pain elicited by the insult; (2) selecting techniques of analgesic drug administration that act on pathways or anatomical locations where the nociceptive information is being processed or originating from; (3) combining analgesic drugs that act on different pain pathways; and (4) provide the best possible comfort for the animal. Prognosis: Providing pain relief improves the animal's well being and outcome; however, interpreting and diagnosing pain remains difficult. Continuing research in pain management will contribute to the evaluation of the pathophysiology of pain, pain assessment, and newer analgesic drugs and techniques.  相似文献   

The induction of 1,3-β-glucanases and other enzymes in groundnut leaves infected with Cercospora arachidicola     

S. Roulin  A. J. Buchala 《Physiological and Molecular Plant Pathology》1995,46(6)

Infection of groundnut leaves with the early leaf spot pathogen Cercospora arachidicola leads to a marked increase in extracellular 1,3-β-glucanase activity, limited to the infected tissue. Three isoforms of low molecular weight and extreme pI values, typical of pathogenesis-related proteins, were induced. These β-glucanases, when acting together, were capable of degrading the pathogen cell wall in vitro. Glucanases from homogenates of infected leaf tissue were partially purified by ion-exchange chromatography to give enzymes with molecular weights of 35, 32 and 20 kDa and pI values of 3·8, 3·6 and > 9, respectively. They were electrophoretically identical to the β-glucanases found in the intercellular washing fluid. Treatment of groundnut plants with 200 μM mercuric chloride induced the accumulation of identical extracellular β-glucanases. During the course of the infection an increase in peroxidase activity was also observed, but chitinase activity remained more or less constant.  相似文献   

Effects of N-methyl-D, L-aspartate on secretion of growth hormone-releasing hormone from the boar hypothalamic-preoptic area and median eminence in vitro     

Estienne MJ  McElwain KV  Barrett JB  Barb CR 《Domestic animal endocrinology》1999,17(4):1156-407

N-methyl-D, L-aspartate (NMA) elicited secretion of growth hormone (GH)-releasing hormone from both the hypothalamic-preoptic area and the median eminence that were collected from boars. We suggest that the previously described increase in GH secretion that follows peripheral treatment of swine with NMA is attributable, at least in part, to NMA-stimulated secretion of GH-releasing hormone from the central nervous system.  相似文献   

南方发展草畜业的几点思考     

洪振海  何仕林 《安徽农业大学学报》2002,(2):41-43

世界农业由子实体向营养体的转型、北方休牧还草政策的出台以及南方理想的自然条件和市场空间,为草畜业发展提供了千载难逢的机遇;南方发展草畜业不失为一条帮助农民快速致富的有效途径;只要破解观念更新、资金筹措、技术传授三大难题,草畜业定能成为南方农业的主要板块。  相似文献   

大学生就业意向的研究     

蒋传和  王琼  孙伟 《安徽农业大学学报》2002,(5):111-113

本文针对大学生就业中的个人职业选择性就业问题,根据彼德罗夫斯基“动机系统理论”的相关观点,在就业心理上,提出了”就业意向”的概念。尝试性地构筑了就业意向的初步结构,并就此作了实际的调查研究,阐明了大学生就业观念的变化及其与现实要求之间存在的差距,强调了应进一步加强狱业意向”的研究和就业指导工作。  相似文献