鸡传染性法氏囊病毒VP2蛋白B细胞抗原表位预测

以鸡传染性法氏囊病毒VP2蛋白的基因组序列为基础,采用Garnier-Robson方法、Chou-Fasman方法和Karplus-Schultz方法预测VP2蛋白质的二级结构;用Kyte-Doolittle方案预测蛋白质的亲水性;用Emini方案预测蛋白质的表面可能性;用Jameson-Wolf方案预测氨基酸的抗原性指数。综合分析,预测VP2蛋白的抗原表位。通过以上几种方法预测IBDV病毒VP2蛋白的B细胞表位位于VP2蛋白N端3-10、30-45、77-84、150-157、197-206、211-222、278-288、298-303、315-325、376-381、386-394、403-411、415-425区段。     

蛋白质周转代谢及其测定

蛋白质是生物体的重要组成部分。动物蛋白质周转是动物体内蛋白质积累形成动物产品的唯一生物学途径和基本生物学机制 ,是生物体细胞结构和功能的根本动力学过程。本文对蛋白质周转代谢的概念、术语、动物蛋白质周转代谢的意义做了阐述 ,介绍了蛋白质周转代谢的测定方法 ,并重点介绍了蛋白质周转代谢的随机分析与房室分析方法。     

牛子宫复旧过程中胶原蛋白和肌浆球蛋白降解规律的研究

本实验监测8头围产期奶牛外周血浆中胶原蛋白和肌浆球蛋白的代谢产物——羟基脯氨酸(HP)和3甲基组氨酸(3MH)的含量,借以找出这两种蛋白质的代谢规律和子宫复旧的关系。结果表明:荷兰黑白花牛和娟珊牛血浆中HP的含量和子宫角直径分别呈显著及极显著正相关(r=0.41,P<0.05和r=0.57 P<0.01),而3MH分别呈极显著和显著正相关(r=0.52 P<0.01和r=0.39(P<0.05)。此外,黑白花牛血浆中3MH的含量极显著高于娟珊牛(P<0.001)。两个品种牛子宫复旧的平均时间,黑白花牛为37.4±3.1天,娟珊牛32.3±2.1天。结果说明牛产后子宫体积的缩小与子宫肌肉的胶原蛋白和肌浆球蛋白降解成氨基酸排出体外有关,子宫复旧的速度可能决定于这两种蛋白质的降解速度。     

复方中药多糖对体外脾淋巴细胞增殖、NO生成和蛋白激酶G的影响

将5种不同浓度复方中药多糖(CPPS)加入到小鼠脾淋巴细胞中培养48 h,观察CPPS对小鼠脾淋巴细胞增殖、对体外培养的脾淋巴细胞中NO的生成和蛋白激酶G(PKG)活性的影响。结果显示,CPPS能显著提高淋巴细胞增殖,显著升高细胞培养液中NO的生成,细胞内PKG活性明显提高,且CPPS、NO和PKG与淋巴细胞增殖有一定相关性。CPPS可能通过NO介导信号通路,引起第二信使环化鸟苷酸(cGMP)生成,从而提高PKG活性促进淋巴细胞的增殖,发挥其免疫调节作用。     

Production of irrigated Trifolium repens L. under a cutting regime in the subtropical region of Gauteng,South Africa

Abstract

The productivity of Trifolium repens L. cv. Ladino, under irrigation in the subtropical region of Gauteng, South Africa, is unknown. The performance of T. repens was determined over five years (1981/1982 to 1985/1986), at two defoliation frequencies, four levels of nitrogen (0, 400, 800 and 1 600 kg N ha^?1 ‐ total applied over five years), and either the removal or recycling of harvested material. Frequent, compared to infrequent defoliation, resulted in higher dry matter (DM) yields from the second year onwards. Dry matter yields were positively affected by the recycling of material, compared to no recycling. A mean DM yield of 191 ha^?1 in the first year and 12 t ha^?1 in the final year, was obtained. The highest DM yields occurred during October for all years and lowest DM yields from January to March. The first and final year showed similar peaks (late October) and troughs (March till April). Crude protein (CP) content of the herbage was influenced more by frequency of defoliation than recycling of material, where the highest CP content in any year was obtained from frequent defoliation. Nitrogen fertiliser applied up to a total of 1 600 kg N ha^?1 over five years had no effect on either DM yield or crude protein content. This study has shown that T. repens could be a productive pasture for at least five years in the subtropical region of Gauteng, South Africa. Productivity and quality of T. repens were enhanced by a defoliation interval of less than five weeks and when soil high fertility was maintained by recycled plant material.     

低蛋白质对猪胴体品质的影响

本文综述了补充平衡氨基酸的低蛋白质日粮时于断奶仔猪及肥育猪的生产性能、胴体品质、脏器重量影响的研究,并分析了低蛋白质日粮对其生产性能和肉质影响的可能原因.     

烘干鸡粪作为蛋白质饲料的应用研究

把采集的新鲜鸡粪运用先进合理的加工工艺烘干后，作为一种蛋白质饲料加入畜禽的日粮中，具有无毒、适口性好、转化率高、价格低廉等优点，通过试验表明可部分取代植物性蛋白质饲料，从而降低养殖成本。鸡粪作为一种环境污染源，在环境保护呼声越来越高的今天，鸡粪通过先进合理的加工处理可制成优质饲料，又可加快社会环境的综合治理步伐，具有巨大的经济效益、社会效益、生态效益。     

The effect of intravenous fresh frozen plasma administration on fibrinogen and albumin concentrations in sick neonatal foals

This study investigated the immediate (6 h or less) effects of fibrinogen and albumin contained in transfused equine origin fresh frozen plasma on those proteins when measured in sick neonatal foals. Fibrinogen and albumin concentrations were measured in the administered plasma and in 31 sick foals at admission to a referral neonatal intensive care unit. Additional samples were obtained from the foals at 2 and 6 h following transfusion. No changes in albumin concentration were recognised. The main determinant of fibrinogen concentration following transfusion was the concentration of fibrinogen in the foal at admission. Importantly, intravenous transfusion of equine fresh frozen plasma did not result in immediate (6 h or less) increases or decreases in the fibrinogen concentration in the recipient foals. Fibrinogen from the donor contained within transfused plasma will not directly affect fibrinogen concentrations measured at later times.     

Src基因研究进展

Src是非受体蛋白酪氨酸激酶家族成员之一,属原癌基因,Src表达及活性异常往往引起乳腺癌、结肠癌、胰腺癌、前列腺癌、肺癌等某些肿瘤发生、发展。最近研究表明Src基因与乳腺的提前退化及泌乳失败相关。文从Src基因的定位、蛋白质结构、分布及功能等几方面进行简要的介绍。     

甲型流感病毒多功能蛋白质NS1的研究进展

近年来大量的研究结果表明,甲型流感病毒的非结构蛋白质1(NS1)是在感染病毒期间具有多个辅助功能的毒力因子,为揭示该人畜共患病毒的致病性机理提供重要参考价值。这篇文章综述了该病毒蛋白质一些最新研究进展,包括NS1的合成、结构、亚细胞定位及在病毒复制机制、宿主天然免疫应答或/和适应性免疫应答、细胞信号传导中发挥各种作用。作者重点阐述了NS1-RNA之间和NS1-蛋白质之间的相互作用,因为它们都是上述功能和过程的基础。同时突出不同毒株NS1蛋白可能特有的特性,鉴于此,也讨论了NS1对人和动物甲型流感病毒致病性的某些作用。最后概述NS1可能应用于流感疫苗的研制、新抗病毒药物的研发等。同时比较了乙、丙型流感病毒NS1研究新进展。