应用反转录聚合酶链式反应检测鸡Th1样淋巴因子mRNA表？…

应用反转录聚合酶链式反应（ＲＴ－ＰＣＲ）和限制性酶切分析技术对鸡脾细胞体外受到有丝分裂原ＣonＡ刺激的情况下,其Ｔh1样淋巴因子mＲＮＡ的表达水平进行了研究。实验结 果表明,ＣonＡ诱导培养３个小时的鸡脾细胞表达α－干扰素（ＣhＩＦＮ－α）、γ－干扰素（ＣhＩＦＮ－γ）和白细胞介素－２（ＣhＩＬ－２）等鸡的Ｔh1样淋巴因子mＲＮＡ 。未诱导但培养了３小时的鸡脾细胞可表达ＣhＩＦＮ－α和ＣhＩＦＮ－γmＲＮＡ,而未     

藏山羊乳主要营养成分及乳酶、乳清蛋白的研究

本文研究了分布于西藏和四川地区的藏山羊乳蛋白、乳糖和乳脂含量,并对乳中4种酶活力及乳清蛋白的组成进行了研究。结果表明:藏山羊乳中3种营养成分存在一定的地区差异,脱脂乳中乳酸脱氢酶,碱性磷酸酶,γ-谷氨酰转肽酶、乳过氧化物酶活力分别为81.9±37.8、7.7±3.5、437.4±93.0、532.7±202.6单位。乳过氧化物酶在体外可被10~(-5)M的硫氰酸根或乳酸根活化。用琼脂糖凝胶电泳可将乳LDH分出LDH_1、LDH_2和LDH_3三带,各带所占百分比例分别为50.6±4.5、31.6±4.2和17.8±3.3,提示乳LDH不是来源于血液。用SDS—PAGE可将乳清蛋白分出5条区带。     

赛里木拉丝酸奶中优势菌株发酵乳对血管紧张素转化酶的抑制作用

利用改进的紫外分光光度法,测定从新疆赛里木拉丝酸奶中分离出的瑞士乳杆菌mb2-1、嗜热链球菌mb5-1以及马克斯克鲁维酵母Y6单菌和混菌发酵脱脂乳对血管紧张素转化酶抑制率。结果表明:瑞士乳杆菌mb2-1、嗜热链球菌mb5-1单菌发酵对血管紧张素转化酶抑制率48h达到最高,分别为70.75%、47.17%;与马克斯克鲁维酵母Y6混合发酵48h,对血管紧张素转化酶抑制率分别为75.68%和44.85%。     

Changes in growth performance, digestive enzyme activities and nutrient digestibility of cherry valley ducks in response to aflatoxin B1 levels

The objective of this study was to investigate toxic effects of aflatoxin B1(AFB₁) on growth performance, organs, hepatic enzyme activities, apparent digestibility of nutrients and digestive enzyme activities in ducks. Ninety 1-day-old Cherry Valley commercial ducks were designed to three treatment groups with three replicates of ten birds each. Group I (control) was fed conventional feed free of AFB₁, group II or III was fed the diets containing 20 μg/kg or 40 μg/kg AFB₁-contaminated rice respectively. The feeding trial lasted 6 weeks. The results were that decreased body weight gain and feed intake, increased feed to gain ratio and selected organ weights (liver, kidney and pancreas) were observed in AFB₁-treated groups. The activities of serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were significantly increased in AFB₁-contamined groups. The apparent digestibility of crude protein (CP) was significantly lower while activities of digestive enzyme from duodenum contents including protease, chymotrypsin, trypsin and amylase were increased in AFB₁-treated group. These results indicated that AFB₁ of feed could decrease growth performance and apparent digestibility of nutrients, change digestive enzyme activities of duodenum contents in duck.     

超高压均质对牛乳中微生物和酶的影响研究进展

超高压均质作为一种新兴的加工方式,与传统热处理和静态超高压相比,动态超高压处理具有可连续化、经济及热负荷低等诸多优点.随着压力的提高,高压均质带来的剪切、湍流和空化现象急剧增加,产品在处理过程中的温度瞬间增加,这为牛乳的杀菌和灭酶提供了新的途径.本文总结超高压均质在牛乳微生物和酶中的应用研究,现有的研究表明超高压均质对...     

遮荫胁迫下外源一氧化氮对高羊茅的生理调控作用

用外源一氧化氮(NO)供体硝普钠(SNP)处理遮荫胁迫下的2个高羊茅(Festuca arundinacea)品种,探讨外源NO对遮荫胁迫下其叶绿素含量、膜透性、丙二醛(MDA)含量、抗氧化酶活性及脯氨酸(Pro)含量的影响.结果表明:外源NO可以显著提高遮荫胁迫下高羊茅叶片的叶绿素含量(P＜0.05),减弱质膜相对透性的增加,减缓膜质过氧化产物MDA含量的升高,促进Pro的积累,提高超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)的活性(P＜0.05).遮荫胁迫下高羊茅品种踏火二号的电解质渗透率、MDA含量、CAT活性和Pro含量的变化显著(P＜0.05),NO的作用效果     

番鸭血浆酶活性及其与产肉性能关系的研究

用法国＊本地二元杂交鸭为研究对象,分析其宰前血浆ＧＯＴ、ＧＰＴ、Ａｋｐ、ｒ－ＧＴ、Ａｍｙ活性与７个产肉性状的表型相关,结果表明ＧＯＴ活性与屠宰率,胸肌率,腿肌率,观众 率,ＧＰＴ活性与胸肌率,瘦肉率、ｒ－ＧＴ活性与胸肌率,腹脂率均呈显著正相关;