利用PCR对鸭瘟和鸭"传染性肿头症"的鉴别诊断

本文利用聚合链反应(PCR)技术对鸭瘟和鸭“传染性肿头症”进行鉴别诊断。结果证明该方法具有特异、快速的特点。可对这两种临床症状较为相似的鸭传染性疾病进行快速鉴别诊断。     

家禽核酸疫苗的研究进展

核酸疫苗是当今疫苗研究的最前沿领域，本文就核酸疫苗在家禽传染病中的应用做一综述。     

Inhibitory effects of LDL-ACM complex on subcutaneous implanted tumors in nude mice()

AIM: In order to evaluate the applicable value of LDL as a targeted vehicle for chemotherapeutic agents, we investigated and compared the inhibitory effects of LDL-ACM complex and free ACM on nude mice's subcutaneous implanted tumors derived from gastric cancer cell lines, SGC-7901 and NKM-45. METHODS: LDL-ACM complex was prepared and the tumor model of nude mice was established by subcutaneous implantation of SGC-7901 and NKM-45. Then, the groups of nude mice developed subcutaneous implanted tumors were received either LDL-ACM complex or free ACM. Subsequently, the tumor size, weight and leukemia cell counts were measured and the rates of tumor-inhibition and the survival were compared among the groups. RESULTS: The inhibitory effects of LDL-ACM complex on the tumors, especially on SGC-7901 implanted tumors were much more obvious than that of free ACM. It was also indicated that the action of LDL-ACM complex was mediated by LDL receptor. CONCLUSION: These results showed that LDL-ACM complex had significant inhibitory effects on the implanted tumors and the effect might be mediated by LDL receptor.     

中国苜蓿繁育概述

回顾了建国以来国内苜蓿的育种发展状况,进行了苜蓿的种质评价与筛选,地方品种的系统化,育成了抗寒新品种草原1号、草原2号,抗病品种中兰一号,耐盐品种中苜一号,耐牧根蘖品种公农3号、中图3号、中图4号,高产的公农1号等。提出了在我国苜蓿育种方法上,杂交育种与基本育种方法在当代育种中将继续存在,生物技术在育种中的应用将加快育种进程;指出了我国苜蓿育种存在的问题是育种体系不健全,育种手段方法落后,抗性育种缓慢,对引入品种缺少理论与实践的鉴定、评价,国内育成品种少,高层知识力量薄弱等。     

稻-鸭生态系统中二化螟消长动态研究

2003年4～10月,在稻鸭共栖田中,对二化螟发生规律的系统研究结果表明,稻田养鸭能显著减轻二化螟的为害。与对照相比,中稻田养鸭区二化螟为害株率减少13.4%～47.1%;晚稻田减少62.2%。稻鸭共栖能减少化学农药的使用量,具有较好的经济、社会和生态效益。     

Cortical gene expression pattern in rat focal cerebral ischemia

AIM: To investigate the genes differential expression in cortex during rat focal cerebral ischemia.METHODS: cDNA microarray chips containing numerous cDNAs were used to investigate the gene expression pattern between samples of focal cerebral ischemia and sham-control operation rats. RESULTS: Two hundred and eleven genes differentially expressed were screened out, among these genes, up-and down-regulated genes were 199 and 12, respectively. CONCLUSIONS: The analysis of gene expression pattern of focal cerebral ischemia based on cDNA microarray can realize high-throughput screening of the genes associated with the focal cerebral ischemia. The differential expression of genes may be related to the pathogenesis of focal cerebral ischemic diseases.     

冷季放牧补饲对甘肃高山细毛后备母羊瘤胃代谢参数及瘤胃微生物数量的影响

旨在筛选出甘肃高山细毛羊后备母羊科学合理的补饲料,改变牧区由于营养供给不足导致甘肃高山细毛羊2.5岁才能配种的饲养方式。试验选择甘肃高山细毛羊(12月龄)48只,随机分为试验a(1号料)、b(2号料)、c(3号料)组和对照组(不补饲),进行90 d放牧补饲试验。结果表明,1)瘤胃pH试验a组和b组差异极显著(P<0.01)、c组显著(P<0.05)低于对照组,瘤胃氨态氮、蛋白氮、总氮浓度试验组均极显著高于对照组(P<0.01),总挥发性脂肪酸(VFA)试验a组和b组均极显著高于对照组(P<0.01),b组显著高于c组(P<0.05);乙酸和丙酸摩尔比a组极显著高于对照组(P<0.01),b和c组显著高于对照组(P<0.05);丁酸摩尔比a组极显著高于c组(P<0.01);乙/丙b组显著低于对照组(P<0.05)。2)瘤胃纤维降解菌和原虫数目试验组均极显著(P<0.01)或显著(P<0.05)高于对照组。综上所述,补饲均能正向影响甘肃高山细毛羊后备母羊瘤胃代谢参数及瘤胃微生物数量,以1号料补饲效果最优,2号料也能起到理想效果。     

补饲水平对甘肃高山细毛羊生产性能的影响

为了探讨补饲水平对高寒牧区甘肃高山细毛羊生产性能的影响,本研究选择12月龄甘肃高山细毛后备母羊48只,随机分为补饲Ⅰ组(颗粒饲料)、Ⅱ组[玉米(Zea mays)和苜蓿(Medicago sativa)干草]、Ⅲ组[玉米、苜蓿干草和燕麦(Avena sativa)干草]和对照组(不补饲),进行冬春季"放牧"+"补饲"试验,比较了后备母羊体重,剪毛量,毛纤维长度、细度、白度、强度和伸度等物理指标。结果表明,试验Ⅰ组、Ⅱ组和Ⅲ组试验羊平均日增重分别比对照组高148.29%、133.09%、96.76%;剪毛量各组之间差异不显著(P0.05);自然长度和伸直长度对照组均极显著低于Ⅰ、Ⅱ、Ⅲ组(P0.01),且自然长度Ⅰ组极显著高于Ⅱ组和Ⅲ组(P0.01),伸直长度Ⅲ组极显著低于Ⅰ组和Ⅱ组(P0.01),Ⅱ组显著高于Ⅰ组(P0.05);细度(直径)Ⅰ组最大,Ⅰ组极显著高于对照组(P0.01),且显著高于Ⅱ组(P0.05);白度Ⅰ组最高,Ⅰ组显著高于对照组(P0.05),其他各组之间均差异不显著(P0.05);强度和伸度补饲组均极显著高于对照组(P0.01),且强度Ⅰ组极显著高于Ⅱ组(P0.01),伸度Ⅰ组显著高于Ⅱ组(P0.05)。由此可见,补饲对体重、羊毛品质都有显著正向影响,高寒牧区冬春季节牧草营养缺乏,为了满足羊只营养需要,使甘肃高山细毛羊后备母羊能在1.5岁进行配种繁殖,在冷季放牧的基础上补饲1号料为最佳选择。     

杏鲍菇多孢分离菌株ISSR、RAPD分子标记及体细胞不亲和性分析

通过杏鲍菇多孢分离菌株的ISSR、RAPD分子标记和体细胞不亲和性分析,体细胞不亲和性分析得出子代杏1、杏3、杏4与出发菌株湘杏98有拮抗线,杏1、杏2、杏3、杏4四株子代均有明显的拮抗线。16条ISSR引物和19条RAPD引物分别扩增出99、154个条带,多态性条带分别占48.48%、61.00%;相似系数变异范围分别为0.63~0.86、0.57~0.83。湘杏98、杏2、杏3在2种标记的聚类结果上存在差异。体细胞不亲和性分析从表型上(拮抗线有无)反应了菌株的遗传变异。RAPD标记遗传相似系数小于ISSR标记,表明ISSR标记更适合亲缘关系较近的种群间遗传多样性分析。