大鼠BDNF基因真核表达载体的构建

从23日龄大鼠脑组织中抽提总RNA,应用RT-PCR技术扩增脑源性神经营养因子(BDNF)基因片段,将此片段克隆入T载体,酶切反应鉴定。然后双酶切BDNF-T载体和空质粒pEGFP(N1),将所获目的片段和线性空载体用T4 DNA连接酶连接,构建真核表达载体pEGFP(N1)-BDNF,并进行酶切反应鉴定及DNA测序。序列测定的结果与GenBank比较,所克隆的BDNF基因从起始密码子ATG到终止密码子TAG全长共750 bp序列完全相同。结果表明成功构建真核表达载体pEGFP(N1)-BDNF,为进一步研究BDNF基因表达,神经系统疾病治疗和生物制药奠定基础。     

犬瘟热实验室诊断方法研究进展

犬瘟热病毒(CDV)为副粘病毒科,麻疹病毒属成员,由carré于1905年首次分离发现。随着近年来研究的不断深入,发现犬瘟热病毒的感染范围在不断的扩大。犬瘟热病毒不仅可以感染犬科(如犬、狐、狼等)、鼬科、浣熊科、猫科(如狮、虎、豹)等多种肉食动物[1-6],在实验室条件下还可以感染灵长类,引起脑脊髓炎,以及感染人的神经细胞[7,8]。目前已有日本猕猴和野猪自然感染CDV引起的致死性脑炎的临床病例报道[9-10]。Hoyland J A等[11]通过原位RT-PCR技术证实了患Pa-grts骨病的病人组织中含有犬瘟热病毒核酸,但犬瘟热是否会成为继狂犬病之后通过…     

河北省奶牛牛病毒性腹泻/粘膜病病毒的分离鉴定

从河北省某规模化奶牛场牛病毒性腹泻/粘膜病(BVD/MD)疑似病例中采集病料,将处理好的病料接种MDBK细胞,盲传9代,得到了不产生细胞病变的病毒。琼脂扩散试验表明本病毒能与牛病毒性腹泻病毒(BVDV)OregonC24标准阳性血清反应,出现沉淀线;细胞培养物用BVD/MD荧光抗体染色检测,可见到荧光着染的特异性细胞,荧光颗粒出现于胞浆中。双抗体夹心ELISA检测病毒抗原结果BVDVOregonC24VP/N为3.141,分离毒P/N为3.012,P/N>2,与BVDVOregonC24V结果一致;电镜观察到圆形、直径为40～60nm,有囊膜,囊膜表面有突起的病毒粒子,与BVDV颗粒基本一致。经RT-CR检测,扩增出了唯一的315bp的目的条带,进一步证实为牛病毒性腹泻/粘膜病病毒。     

猪圆环病毒2型PCR检测方法的建立及应用

根据Genbank中PCV2全基因组序列设计了扩增片段大小为262bp的引物P1/P2,建立了检测猪圆环病毒2型PCR方法。引物对P1/P2从PCV2阳性病毒感染基因组中扩增出特异性条带的最低DNA含量为10-9ng/mL(约100个PCV2病毒)。用该方法对陕西和甘肃的103份临床发病猪的肺脏和淋巴结样品进行检测,结果有68份样品检测出阳性,阳性率为66%。     

生防菌34-9对柑桔防腐保鲜效果的研究

柑桔安全(无毒)防腐保鲜关系到人体健康、国际贸易、柑桔生产和农业经济的发展。柑桔果实容易受到青霉、绿霉和蒂腐菌的侵染而造成腐烂损失[1-4]。目前,控制柑桔采后病害的主要手段是使用化学杀菌剂,但它在柑桔中的残留毒性对人类健康存在潜在危险,已成为全社会关心的问题。原先用于柑桔采后处理的化学杀菌剂现在陆续已被禁止使用,如双胍盐等[5]。此外,杀菌剂长期在某一地区使用会导致抗药菌株的产生,从而降低其防治效果,其结果是,化学杀菌剂的使用剂量及其化学残留量大大加重,对人类健康的威胁也加大。因此,迫切需要研制一些新的、无毒高效…     

无籽西瓜枯萎病抗性的遗传分析

西瓜枯萎病（Fusarium oxysporum f．sp．niveum）是西瓜生产中的毁灭性病害，培育和应用抗病品种是防治此病害最经济有效的措施。我国自20世纪80年代开展西瓜抗枯萎病育种以来，已培育出一批抗病品种并在生产上推广应用，但主要集中于二倍体西瓜，在三倍体无籽西瓜育种方面几乎没有涉及，因此无籽西瓜生产中缺少抗枯萎病品种。生产上对无籽西瓜枯萎病的防治主要是采用嫁接，防病的效果也较为理想，但嫁接增加了生产成本而且还存在不亲和、果实品质降低等问题。目前无籽西瓜生产面积正在逐年扩大，适时开展无籽西瓜抗枯萎病育种是满足生产需要、有效防治病害的根本途径。本试验采用NCⅡ杂交设计配制了部分无籽西瓜组合，鉴定双亲及F1的枯萎病抗性并进行配合力分析，以初步了解无籽西瓜抗枯萎病组合双亲选配的一般规律。     

Canine renal failure syndrome in three dogs

Three dead dogs were brought to the College of Veterinary Medicine, Kyungpook National University for study. Clinically, all the dogs showed emaciation, anorexia, depression, hemorrhagic vomiting and diarrhea for 7~10 days before death. All the clinical signs were first noted for about one month after feeding the dogs with commercial diets. At necropsy, all 3 dogs had severe renal damage with the same green-yellowish colored nephroliths in the renal pelvis. They also showed systemic hemorrhage and calcification of several organs, which might have been induced by uremia. Microscopically, necrosis, calcification and calculi were detected in the renal tubules, and especially in the proximal convoluted tubules and collecting ducts of the kidney. These findings were supportive of a mycotoxic effect, and especially on their kidneys. However, the precise cause of the toxic effect in these cases of canine renal failure could not be determined.     

Multiple intestinal lymphomatous polyposis in a Jindo dog

A male, 5-year-old Jindo dog underwent enterectomy and enteroanastomosis due to ileus of the intestine at a local veterinary hospital. Grossly, the excised intestine showed markedly thickened multinodular masses in the serosal layer of the upper part, and soft-to-firm, cream-colored neoplastic masses that displayed extensive nodular mucosal protuberances into the lumen. The neoplastic masses were filled with large round cells that were ovoid in shape and they had pale and/or hyperchromatic nuclei. The neoplastic cells had mainly infiltrated into the mucosal and submucosal layers, and they had diffusely invaded the muscular and serosal layers. Therefore, the diagnosis of canine multiple intestinal malignant lymphomatous polyposis was made based on the gross and histopathological findings. The origin of these tumor cells was determined to be B-cells since they were positive for anti-CD20.     

转基因番茄F2代的贮藏特性研究

以F1′、F2、F3、NR四个转基因番茄基因型为实验材料,研究了转反义乙烯基因F2代番茄果实的贮藏特性,据此对转基因番茄各基因型的贮藏特性作综合分析评价。结果表明,F3基因型果实的失重率、腐烂率最低,果柄拉力最大,外观形态最好,贮藏特性最好;其次是F1′和NR基因型;而F2基因型最差。     

基于颠茄发根的外源基因表达系统的建立

 用携带植物高效表达载体pCAMBIA1304 ⁺ “解除武装”的重组C58C1工程菌转化颠茄无菌苗真叶, 发根诱导率达100%。PCR检测证实发根型质粒pRiA4和表达型质粒pCAMBIA1304 ⁺均能整合到颠茄发根基因组内, 共转化率达30%。建立了基于颠茄发根的高效外源基因表达系统, 为将托品烷类生物碱东莨菪碱的生物合成关键酶基因导入颠茄, 实现其次生代谢工程及开展分子育种奠定了基础。