马立克氏病肿瘤相关的表面抗原研究进展

马立克氏病肿瘤相关的表面抗原是MD肿瘤细胞和MD成淋巴细胞系细胞表面存在的特异性抗原,在此综述了马立克氏病肿瘤相关的表面抗原的细胞分布、分离纯化,理化特性等方面的研究进展,指出马立克氏病肿瘤相关的表面抗原在马立克氏病的肿瘤免疫和鉴别诊断中具有重要的意义。     

马立克氏病肿瘤表面抗原的免疫荧光测定及其应用

用马立克氏病(MD)肿瘤细胞系 MDCC-MSB-1免疫家兔制成的高免血清,经正常的来杭鸡淋巴细胞完全吸收后,获得针对 MD 肿瘤表面抗原(MASTA)的特异性抗血清,它与 MSB-1反应的间接免疫荧光效价为1∶32。以MD 京-1强毒株接种1日龄雏鸡诱发的实验性肿瘤和某鸡场疑似马立克氏病的内脏肿瘤制成细胞悬液,用 MASTA 特异性抗血清进行间接免疫荧光染色,测得内脏肿瘤细胞的 MASTA 阳性率分别为2%和15%,并从疑似 MD 的病鸡血液内分离出 MD Ⅰ型病毒。羽囊和血清琼扩 MD 阳性,但无肿瘤病变的鸡未能测出MASTA 阳性的肿瘤细胞。用荧光抗体染色检查 MASTA 抗原的 MD 诊断方法切实可行。     

鸡对马立克病病毒及可移植性肿瘤细胞株的遗传性抵抗力

用 MD 病毒和移植性马立克氏病肿瘤细胞株,对以正常血清中 IgG 量的高低两个指标选育的两个品系进行了接种试验。试验表明,L 品系鸡对 MD 病毒的抵抗力比 H 品系鸡强;而对可移植性马立克氏病肿瘤细胞的抵抗力,H 品系鸡却明显强于 L 品系鸡。     

鸡马立克氏病的治疗

鸡马立克氏病(MD)是鸡常见的一种淋巴组织增生性疾病,是由马立克氏疱疹病毒引起的具有高度传染性的肿瘤疾病,主要危害3-5月龄的鸡,死亡率可高达80%,尤其是未经马立克氏病疫苗免疫的鸡群更易爆此本病。     

如何科学防治鸡马立克氏病

1鸡马立克氏病的分类 马立克氏病（MD）是鸡的一种常见和重要的肿瘤性疾病,由血清1型疱疹病毒（MDV）引起,根据其临床表现和病变发生的部位,可分四种类型：神经型、内脏型、眼型和皮肤型。     

蛋鸡马立克氏病的诊断与防治

马立克氏病简称MD,由疱疹病毒科中的马立克氏病疱疹病毒引起的最常见的鸡恶性肿瘤病（癌）。以淋巴细胞组织增生,在各内脏器官以及外周神经、肌肉、皮肤中产生单核细胞浸润和肿瘤为特征。有传染性,能导致鸡大批死亡,是养鸡业的很大威胁。     

鸡马立克氏病毒疫苗的种类和应用

鸡马立克氏病毒（MDV）疫苗目前分为如下5类：血清Ⅰ型马立克氏病毒疫苗,血清Ⅱ型马立克氏病毒疫苗,血清Ⅲ型马立克氏病毒疫苗,马立克氏病毒多价苗,马立克氏病毒基因工程苗。马立克氏病毒疫苗的应用,应结合鸡马立克氏病（MD）的流行病学特点和马立克氏病毒疫苗的特性进行合理选择应用。     

鸡马立克免疫失败的原因及防治对策

鸡马立克氏病（MD）是一种由疱疹病毒引起的具有高度传染性的肿瘤性疾病。鸡群如发生急性MD则往往引起大批死亡，甚至全群覆没。本文对造成鸡马立克氏病免疫失败的各种原因进行了分析．从五个方面提出了切实可行的防治措施．对规模化养鸡场及农户养鸡具有较高的参考价值。     

鸡马立克氏病免疫研究的新进展（综述）

鸡马立克氏病(MD)是一种由疱疹病毒引起的传染性肿瘤病。病的特征是在各种脏器形成淋巴细胞性肿瘤,近年又发现由受此病侵害的动脉壁细胞所导致的动脉硬化(MiMk等,1979)。 此病首先于1907年由匈牙利的马立克氏所报道。以后不少学者根据本病的各种症状和病变曾给以各种命名。直到1961年,由英国Biggs氏倡议,才统一采用了马立克氏病     

鸡马立克氏病病理组织学的观察

马立克氏病(简称MD)是由马立克氏病疱疹病毒(MDHV)引起的鸡最常见的淋巴细胞增生肿瘤性疾病。本病有高度传染性,其特征是周围神经以及性腺、虹膜、内脏器官、肌肉和皮肤的淋巴细胞样细胞浸润。MD在世界养鸡业发达的国家中广泛发生和流行。近年来,我国北京、上海、广州、哈尔滨、大连、青岛、济南、新疆、河南等各大城市的养鸡场亦有发生MD的报导。由于MD可     

Study on Hsp90 Expression in Different Tissues and Its Antibody in Serum of Chickens Infected with Marek's Diseases

To investigate the dynamic change of heat shock protein 90 (Hsp90) in the genesis and development of tumor, we successfully established tumor animal model using Marek's disease and then determined the location of Hsp90 in the tumor tissue using immunohistochemistry method, the antibody titer level of Hsp90 in the serum and the expression level in the tissue using enzyme-linked immunosorbent assay (ELISA) method. Our result showed that Hsp90 location in the tumor tissue was significantly associated with the tumor cell and most in the cytoplasm of the tumor cell, and Hsp90 expression level in the tissue and the antibody titer level in the serum was most significantly increased with the development of tumor. This is the first report to show the presence of Hsp90 in tumor tissues induced by the Marek's disease, with its expression correlated to the tumoral grading. These data may also be valuable for developing new molecular anti-cancer therapies.     

Knockdown of the Meq gene in Marek's disease tumor cell line MSB1 might induce cell apoptosis and inhibit cell proliferation and invasion

Marek's disease (MD), a highly cell-associated and contagious disease of chickens caused by Marek's disease virus (MDV) can result in neural lesions, immunosuppression and neoplasia in chicken. The Meq gene is an important oncogene in the MDV genome, and it is expressed highly in MD tumor tissues and MD T-lymphoblastoid cell lines. An experiment was conducted to elucidate the role of Meq in MD tumor transformation. RNA interference technology was used to block its expression, and then analyzed the biological effects of Meq knockdown on the MD tumor cell line MSB1. A small interfering RNA with an interference efficiency of 70% (P<0.01) was transfected into MSB1 cells to knock down the expression of Meq gene. The cell proliferation, cycle and apoptosis were detected post-Meq knockdown. The results showed that MSB1 cell proliferation was downregulated remarkably at 48 h (P<0.01), 60 h (P<0.05) and 72 h (P<0.01) post-Meq knockdown. The cell cycle was unaffected (P>0.05). B-cell lymphoma 2 gene (BCL2) was anti-apoptotic and caspase-6 was the effector in the apoptosis pathway. The activity of caspase-6 was upregulated (P<0.05) significantly and BCL2 gene expression was downregulated (P<0.05) significantly post-Meq knockdown, suggesting cell apoptosis might be induced. MSB1 cell migration did not exhibit any obvious change (P>0.05) post-Meq knockdown, but the expression of two genes (matrix metalloproteinase 2 (MMP2) and MMP9) that are correlated closely to cell invasion was downregulated (P<0.05) remarkably post-Meq knockdown. The Meq knockdown might affect the main features of tumorous cells, including proliferation, apoptosis, and invasion, suggesting that the Meq gene might play a crucial role in interfering with lymphomatous cell transformation.     

Analysis of DNA methylation of CD79B in MDV-infected chicken spleen

Marek's disease (MD), an immunosuppressive disease induced by Marek's disease virus (MDV), provides an ideal model for studying diseases caused by a carcinogenic virus. CD79B is a B-cell antigen receptor complex-associated protein β-chain precursor which is involved in the activation, proliferation, differentiation of B-cell and the transmission of downstream signals. This study analyzed CD79B gene mRNA expression and methylation by two schemes #20 (5´ flanking to intron 1) and #27 (intron 2 to intron 3), between MDV-infected tumorous spleens (TS) and non-infected spleens (NS). Results showed that average methylation levels of CpGs in #20 and #27 were higher in TS than in NS (P<0.05), while, CD79B mRNA expression was lower in TS than in NS (P<0.01). Six of 40 CpG sites showed significantly (P<0.05) different methylation levels between TS and NS. Correlation analysis showed that the average methylation level rather than a single site methylation level in #20 affected (P<0.05) mRNA expression. Collectively, it was found that the change of CD79B gene expression after MDV infection might be partly explained by modification of DNA methylation.     

牛兔异种体细胞以兔卵母细胞为核受体的牛体细胞克隆研究

随着同种动物克隆后代的不断降生,人们又开始尝试异种动物体细胞核移植。用兔的卵母细胞作为核受体进行牛的体细胞核移植,研究表明,颗粒细胞作为供核体与兔去核卵母细胞的融合率(60.5%,57.9%)稍高于皮肤成纤维细胞的融合率(52.2%,48.4%),但两者间差异并不显著。颗粒细胞与皮肤成纤维细胞均采用饥饿培养和接触抑制培养两种不同的方式进行诱导处理,融合卵在电激活后能够卵裂并发育的情况差异显著(72.6%对51.4%;70.4%对52.2%)。有少数重构胚发育至囊胚,证明在哺乳动物异种重构胚早期发育中,异种细胞核与细胞质间是相容的。     

鸡3种主要DNA病毒多重感染复合PCR检测方法的建立

依据Gen Bank中注册的鸡马立克氏病病毒(MDV)、鸡传染性喉气管炎病毒(ILTV)、鸡痘病毒(FPV)基因组核苷酸序列中的保守序列设计引物,3种病毒各设计3对引物,共计9对引物,经生物学软件筛选后,得到3对相互匹配较佳的引物。3对匹配引物经单一PCR验证后,优化复合PCR反应条件,确定最佳的退火温度、引物浓度和Taq DNA聚合酶浓度;经特异性、敏感性试验及简化PCR试验,建立简易复合PCR检测方法。复合PCR扩增出的3条带大小与预期一致,即228 bp(MDV)、400 bp(ILTV)、499 bp(FPV);建立的复合PCR方法能同时检测出100 fg MDV、ILTV、FPV的DNA。同时依据PCR技术原理,将经典的三温热循环改进为二温热循环试验,即将退火和延伸合并为一步(62℃),缩短了反应时间。建立的3种病毒的复合PCR检测方法具有较高的特异性和敏感性,可以用于临床病料的快速诊断。     

奥运会男子400m跑的周期性研究

以历届奥运会400m跑前3名的成绩为研究对象,将奥运会男子400m跑整个发展历程分成4个不同的历史阶段,对影响奥运会男子400m跑的绝对速度能力、速度耐力能力两个重要因素进入深入分析,研究结果表明：在奥运会的整个发展历程中,男子400m跑成绩整体呈上升的发展趋势,经历了快、慢、快、慢4个发展周期,下一个将是快速上升发展周期;绝对速度能力整体呈上升的发展趋势,与男子400m跑成绩的发展周期基本相同,速度耐力能力整体呈缓慢上升的发展趋势,与男子400m跑成绩、绝对速度能力的发展周期不同步;绝对速度能力是奥运会男子400m跑的整个发展历程中的主导因素,并影响着前3个阶段的发展趋势,而在1988－2012阶段中,速度耐力能力转变成了主导因素;男子400m跑将进入以速度耐力能力为核心的发展周期,应强调发展运动员的速度耐力能力。     

城镇化对农民增收的作用

增加农民收入是解决“三农”问题的核心。从农民收入构成和变化趋势以及农民家庭经营收入的增长因素等方面进行研究,认为农民收入增长的主要源泉是农民工资性收入的增加。因此,城镇化建设对农民收入增加具有重要作用,应从推力和拉力两方面来加快城镇化建设,为增加农民收入创造条件。     

转基因抗虫棉对农户生产行为的影响分析

以河北主产棉区340个农户2002-2003年的问卷调查和关键人物访谈为依据,分析了转基 因抗虫棉对农户生产行为的影响。结果表明,转基因抗虫棉的应用影响或改变了农户的植棉意向、抗 虫棉种子选择,棉田害虫防治及植棉技术需求等生产行为。     

Vlazov地基上Reissner板相互作用的加权残值分析法

以Vlazov双参数弹性地基上Reissner中厚板为研究对象,建立地基与中厚板相互作用的控制微分方程,运用B样条函数为试函数的加权残值法进行了分析求解,并结合Matlab软件编制程序进行算例分析.算例表明,对于Vlazov地基上四边简支的Reissner板,板的弯剪刚度比的增大可有效地减小板的挠度,亦即减小地基的变形;考虑地基的横向连续性可合理地修正板的挠度和弯矩的值,使其与工程实际更相符.本方法只需划分稀疏的离散网格,便可得到与精确解吻合较好的数值结果,其计算效率与精度均优于全域离散的有限元法.