Effect of dietary vitamin C and ammonia concentration on the cellular defense response of Macrobrachium nipponense

This study examined the effects of dietary vitamin C and ammonia concentration on the cellular defense response of Macrobrachium nipponese . The response of the cellular defense was determined by monitoring changes in reactive oxygen intermediates in hemocytes, superoxide dismutase activity, catalase activity, glutathione peroxidase activity, glutathione reductase and glutathione transferase activity in muscle. The results showed that prawns fed the basal diet had a significant increase in reactive oxygen intermediates in response to exposure to ammonia-N. When dietary vitamin C was added to the feed, there was a significant decrease in reactive oxygen intermediates in response to exposure to ammonia-N. Total superoxide dismutase and glutathione peroxidase activity of prawns fed the basal diet decreased as ammonia-N increased. This decrease in activity was significantly less pronounced in prawns that were fed the dietary vitamin C supplement. In prawns that were fed the dietary vitamin C supplement there was no significant variation in catalase reductase or gluxathione reductase activity in response to variations in ammonia-N concentration. The glutathione transference activity increased at a low concentration of ammonia-N in prawns that were fed the dietary vitamin C supplement, but there was no significant variation in the prawns fed the basal diet. Overall the results indicate that dietary vitamin C supplements enhance the capacity of M. nipponese to respond to elevations in ammonia-N. This response involved several biochemical reactions known to be involved in cellular defense.     

污水污物潜水旋流泵性能及设计方法试验研究

对影响潜水旋流泵性能的6个主要过流件几何参数进行了试验研究，初步掌握了旋流泵叶轮及泵体主要几何尺寸对性能影响的规律。在分析16种优秀水力模型的基础上，计算出叶轮D2及b2函数回归方程式，并用设计实例进行检验，样机效率比国内外同类产品提高3％左右。     

寿光蔬菜叫响"文化品牌"

王高银刹、仓颉双井、圣城古槐等寿光古代及现代的知名景观,全部“搬进”了第六届菜博会的土展厅,不过组成景点的不是土木砖瓦,而是清一色的蔬菜瓜果。这些普通蔬菜瓜果的独到组合,不仅组成了令人留连的“蔬菜大观园”,而且展现出“菜乡”寿光传统的民俗文化和蔬菜产业深厚的文化底蕴。寿光蔬菜种植历史悠久,北魏农学家贾思勰就诞生在这里,明清年间,“独根红”韭菜被确定为宫廷贡品。为叫响蔬菜的“文化品牌”,     

鸡传染性法氏囊病继发大肠杆菌感染的诊断研究

笔者饲养的200多只蛋鸡用种公鸡于50日龄左右突然发病，主要症状为食欲剧减甚至废绝，羽毛逆立，缩颈嗜眠。倒提时口内流出大量黏液状液体，排恶臭白色或微黄带泡沫稀粪，呈水样。发病率达80％，死亡率达32％。剖检可见部分鸡胸肌和腿肌出血，法氏囊水肿出血，个别鸡法氏囊内有黄色较硬的球状分泌物，有的鸡有心包炎和肝周炎，肠道、脾脏和肾脏有出血点。综合以上症状和实验室病毒学和细菌学检测，确诊为传染性法氏囊病继发大肠杆菌感染。     

三种环境因子对大白菜软腐欧氏杆菌根毛吸附的影响

 温度、pH和离子条件是影响病原细菌对寄主吸附的基本因子,文章测定了它们对大白菜软腐欧氏杆菌(Erwinia carotovora pv.carotoyora)在寄主根毛上吸附的影响。病菌在5个给定温度下对寄主根毛吸附量的变化,呈现为由吸附起始温度(18℃)、温度稳恒渐近范围(18-22℃)和温度饱和点(22℃)组成的吸附动力曲线。病菌在12个pH梯度下的运动状态、生活力及对寄主根毛吸附量的变化表明,病菌吸附以pH5.8-7.2为适宜范围,pH4.6和8.2为低限和高限;偏酸(pH5.0以下)和偏碱(pH7.2以上)可通过影响病菌的生活力和运动性而影响吸附。5×10^-6M的Ca++可使病菌吸附量提高2.5-4.2倍,同浓度的Mg++可使吸附量提高2.7倍。文章讨论了温度和pH条件影响吸附的动力学,以及吸附调节的可能机制。     

黄艾美球虫侵犯宿主组织的超微研究

利用透射电镜和扫描电镜相结合的技术对黄艾美球虫（E.flavescens）人工感染后的子孢子移动过程及被虫体寄生的宿主细胞形态学变化和粘膜形态学变化进行了观察。子孢子在进入小肠腺上皮过程中需白细胞介导，在白细胞内可发育成球形的滋养体，观察到有两个子孢子侵入同一白细胞的现象，但分别存在于各自的带虫空泡中，黄艾美球虫引起的肠粘膜损伤主要发生于感染177小时之后，其损伤主要表现在绒毛大片脱落，结缔组织裸露，表面可见到大量破损的孔洞及大量肠杆菌，被虫体寄生的腺上皮细胞基部膨胀，微绒毛脱落，细胞核膨大并部分包被虫体，有些细胞核裂解为二。     

朝阳东大桥承台砼施工技术

叙述了朝阳东大桥主桥两个承台大体积砼的施工经过。总结了施工方案优选过程和大体积低水化热砼的配合比试验情况,并在实际施工中,证明,该技术措施可行,方案经济合理,取得了比较成功的经验。     

Hematological parameters and visceral lesions relationships in rabbit viral hemorrhagic disease.

Twenty rabbits were inoculated with a suspension of Viral Hemorrhagic Disease virus. Hemostatic functions were assessed every sixth hour from 6 to 60 hours post-inoculation. Tissue samples obtained at the same intervals allowed the study of the development of lesions throughout the experiment. Biological signs of Disseminated Intravascular Coagulation (DIC) were detected on and after 30 h post-inoculation and consisted of prolonged One Stage Prothrombin Time and Activated Partial Thrombin Time, the decrease of factors V, VII, and X and high levels of soluble fibrin monomer complexes and D-dimers. A reduction of thrombocyte numbers, heterophils and lymphocytes was associated. The close association of DIC and necrotizing hepatitis lesions suggested the hepatic lesions to be the most important DIC triggering factor. Other mechanisms are discussed.     

电子自旋共振在竹材研究中的应用：竹材自由基研究 二

本文分析和讨论了碱处理对苦竹试样自由基的影响,探讨了经水洗使碱性减弱后试样自由基浓度的变化,并对紫外光照射、温度变化导致的自由基浓度的改变作了测定。结果表明,碱处理对试样自由基浓度有明显降低作用;水洗对减弱碱性对于自由基浓度的影响有一定作用,但不显著;紫外光照射对竹材自由基有微弱作用,但对毛竹、杨木自由基有明显影响;温度对自由基浓度有较大影响,但若试样形态不同,温度与自由基浓度变化关系图也有差异。     

刺槐单株生物量动态研究

本文依据420株刺槐生物量及23株树干解析资料,应用灰色Verhulst模型,对太行山坡地刺槐林单株干、枝、叶、根生物量动态进行了研究,分别建立了预测模型,预测了各器官生长的速生期和停止生长林龄,为实现刺槐林的多目标经营提供决策依据。