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玉米螟微孢子虫作为玉米螟田间种群自然控制因子之一,能否交叉感染家蚕,其与家蚕微孢子虫的血缘关系值得探究。通过对实验室搜集的家蚕微孢子虫和玉米微孢子虫进行了电镜水平的超微结构观察和分析,进而对它们的16S r DNA基因进行了PCR扩增、测序和系统发育分析,结果显示玉米微孢子虫与家蚕微孢子虫均属Nosema属,分别落在不同进化枝上的种,这可能暗示了玉米螟微孢子虫不能直接感染家蚕的部分缘由。 相似文献
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为了探讨家蚕微孢子虫(Nosema bombycis)功能基因组研究方法和手段,利用免疫胶体金标记电镜技术,对被感染的家蚕丝腺组织中家蚕微孢子虫的蛋白质分泌状况进行了观察。结果显示,有大量的胶体金颗粒存在于家蚕微孢子虫寄生位点的宿主组织内,说明了家蚕微孢子虫寄生位点的宿主组织内存在大量的孢子蛋白质,证实了家蚕微孢子虫在寄生过程中将许多孢子蛋白质分泌到宿主体内。初步探讨了家蚕微孢子虫与宿主家蚕之间的互作关系。 相似文献
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家蚕微孢子虫感染家蚕对其中肠和血液蛋白酶活性影响 总被引：1，自引：0，他引：1
本试验测定了不同浓度剂量微孢子虫感染家蚕后,家蚕中肠和血液中蛋白酶的变化.并对不同浓度剂量家蚕微孢子虫感染家蚕后对家蚕发育的影响和不同组织中所含微孢子虫孢子的浓度等作了初步的研究.从本实验中可以看出,感染不同浓度微孢子虫的家蚕,体内相同组织的微孢子虫数量存在显著差异.而感染相同浓度微孢子虫的蚕,不同组织中微孢子虫的数量也有差异,中肠的微孢子虫数量远高于其他部位.感染微孢子虫后,家蚕血液中的蛋白酶活性显著升高,中肠的蛋白酶的活性变化不显著,而感染微孢子虫的数量对血液和中肠中的蛋白酶的活性无显著影响. 相似文献
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广西野外昆虫微孢子虫对家蚕交叉感染情况调查 总被引：3，自引：0，他引：3
为了了解广西野外昆虫微孢子虫对家蚕交叉感染情况,开展了对野外昆虫感染微孢子虫情况调查,并研究其对家蚕的感染性。调查了桑螟、桑尺蠖、菜粉蝶、斜纹夜蛾和桑毛虫等昆虫的微粒子病自然感染率,测试菜粉蝶、桑尺蠖、斜纹夜蛾微孢子虫对家蚕的病原性及可能存在的自然感染方式,观察野外昆虫微孢子虫孢子的形态差异。结果表明:菜粉蝶、桑尺蠖微孢子虫对家蚕蚁蚕的半数感染浓度(IC50)分别为2.69×105个/mL和7.42×105个/mL,斜纹夜蛾微孢子虫对家蚕也具有食下感染能力,菜粉蝶微孢子虫对家蚕也有轻微的胚种传染能力。带病野外昆虫可以通过粪便或鳞毛传播孢子虫。虽然上述野外昆虫微孢子虫的形态与家蚕微粒子孢子虫具有明显差异,但对家蚕都有较强的交叉感染性。 相似文献
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细菌人工染色体(BAC)文库是进行生物基因组学研究的一个重要手段。以家蚕微孢子虫(Nosema bomby-cis)重庆分离株为材料,在前期构建的家蚕微孢子虫基因组框架图数据基础上,对构建家蚕微孢子虫BAC文库过程中的关键技术,如脉冲胶块(plug)的制备与处理、限制性酶的筛选、DNA的部分消化、酶切片段的选择、插入DNA片段与载体的摩尔比值等进行了研究,建立了构建家蚕微孢子虫BAC文库适宜的技术体系。构建的家蚕微孢子虫BAC文库由6 478个克隆构成,克隆片段平均大小约为50 kb,相当于家蚕微孢子虫基因组(15.33 Mb)的20倍,文库空载率较低,有利于深入开展家蚕微孢子虫基因组相关方面的研究。 相似文献
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广东省昆虫微孢子虫资源调查及交叉感染的研究 总被引：11，自引：4，他引：7
为了探明广东省蚕区的家蚕新型微孢子虫来源 ,开展了昆虫微孢子虫资源的调查及昆虫间微孢子虫交叉感染的研究。先后从广东省蚕区家蚕体内分离到 8种新型微孢子虫 ,与家蚕传统微粒子病病原Nosemabombycis相比 ,不论是生物学特性以及对家蚕的病原性等方面均存在明显差异。对广东省不同地区捕捉的 389种昆虫进行显微镜调查 ,从 5 1种昆虫体中检到微孢子虫 ,其中 ,2 8种昆虫分离的微孢子虫可食下感染家蚕 ,18种对家蚕具胚种传染能力。调查了 9种昆虫分离的微孢子虫对 5种昆虫的病原性 ,也见明显的交叉感染现象 相似文献
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通过对家蚕添食新鲜的和存放不同时间的家蚕微孢子虫,判断其微孢子虫的活力变化情况。利用不同株系新鲜的和分别存放在室内干燥自然环境中1年、2年的家蚕母蛾体内微孢子虫对4龄家蚕进行添食试验。添食新鲜的云南株和镇江株家蚕微孢子虫对家蚕都具有很强的感染性,云南株食下感染率达99.0%,镇江株食下感染率达96.5%;添食在干燥的自然环境中存放1年后的母蛾体内家蚕微孢子虫,家蚕的食下感染率云南株为5.5%,镇江株为0;添食在干燥的自然环境中存放2年后母蛾体内家蚕微孢子虫,云南株和镇江株食下感染率均为0。结果表明,在干燥的自然环境中的家蚕微孢子虫随着时间的推移会逐渐失去活性。 相似文献
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家蚕微孢子虫(Nosema bombycis)与其它微孢子虫及真菌的进化关系 总被引：1，自引：0，他引：1
综述了应用分子生物学和生物信息学对家蚕微孢子虫系统发育的研究进展,以及多菌灵等苯并咪唑类杀真菌剂对微孢子虫和真菌的抑制作用,认为研究家蚕微孢子虫和真菌的进化关系对家蚕微粒子病的控制技术研究具有重要参考价值。 相似文献
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新城疫病毒分子生物学研究进展 总被引：1，自引：0，他引：1
新城疫(Newcastle Disease,ND)是由新城疫病毒(NDV)引起的一种急性、高度接触性禽类传染病,被世界动物卫生组织(OIE)定为法定必报传染病,我国也将其列为一类动物疫病,本文从新城疫病毒的形态及分子结构、致病力的分子基础、分子流行病学特征和基因工程疫苗等分子生物学相关研究进展进行了综述。 相似文献
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Peiqiang Yu 《畜牧与生物技术杂志(英文版)》2012,3(1):40
In complex feed structures, there exist main chemical functional groups which are associated with nutrient utilization and availability and functionality. Each functional group has unique molecular structure therefore produce unique molecular vibration spectral profile. Feed processing has been used to improve nutrient utilization for many years. However, to date, there was little study on processing-induced changes of feed intrinsic structure and functional groups on a molecular basis within intact tissue. This is because limited research technique is available to study inherent structure on a molecular basis. Recently bioanalytical techniques: such as Synchrotron Infrared Microspectroscopy as well as Diffuse Reflectance Infrared Fourier Transform molecular spectroscopy have been developed. These techniques enable to detect molecular structure change within intact tissues. These techniques can prevent destruction or alteration of the intrinsic protein structures during processing for analysis. However, these techniques have not been used in animal feed and nutrition research. The objective of this review was show that with the advanced technique, sensitivity and responses of functional groups to feed processing on a molecular basis could be detected in my research team. These functional groups are highly associated with nutrient utilization in animals. 相似文献
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Sandra A. Loftus BA Jill M. Montplaisir BS Jing-wen Kuo MS Dale P. DeVore PhD 《Journal of Equine Veterinary Science》1988,8(2)
A standardized investigation was conducted to compare the biophysical properties of hyaluronate products used in the treatment of joint dysfunction in horses. Results showed that two of the five products, Hyvisc® and Hylartin®V, contained higher-weight molecular hyaluronate (greater than 1.5×106). Other investigations have shown that higher molecular weight hyaluronate is effective in providing physical resistance to shear, in stimulating endogenous hyaluronate synthesis, and in inhibiting excess cell proliferation which may be associated with synovial pannus formation. It is suggested that the therapeutic benefits of hyaluronate products may be dependent on the molecular size of the hyaluronate molecules. Higher molecular weight hyaluronate products would be expected to be more effective than lower molecular hyaluronate products in providing therapeutic benefits. 相似文献
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经济社会的发展使人们对牛肉的经济性和肉品质要求提高,培育生长性能和生产性能更加良好的肉牛品种的重要性日益凸显。随着分子生物学技术的进步,动物育种逐渐从表型性状研究向基因调控发展,通过分子标记辅助育种能够更加快速准确的选择目标性状,分子育种技术提高了品种培育效率并降低了成本,且繁育的后代优良性状更加稳定,其应用范围也越来越广泛。目前新疆肉牛分子育种的应用较少,多停留在理论研究阶段,且存在着经费不足和育种场规模小、难以获得足够的样本等问题。本文综合阐述了分子育种的概述、肉牛分子育种研究进展和新疆肉牛分子育种现状,旨在为新疆肉牛分子育种工作提供一定的思路和理论依据。 相似文献
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Lignosulphonic acids in dialysed sulphite spent liquor and purified lignosulphonic acids were subjected to gel chromatography on Sephadex G-75, G-100 and G-200 and the fractions tested for peptide-precipitating ability. About 56 % of the total lignosulphonic acids in the dialysed sulphite spent liquor had estimated molecular weights above 90000 and about 72 % above 44000. About 94 % of the purified lignosulphonic acids had molecular weights above 90000 and the remaining 6 % had above 36000. The major peptide-precipitating activity of the lignosulphonic acids was due to fractions with molecular weights in excess of 90000. The percentage of peptides in the peptide-lignosulphonic acid precipitates was found to be 80–90. The molecular weights of the peptides used were found to have an upper limit of about 20000. The lower limit for molecular weights of lignosulphonic acid-precipitating peptides is estimated to be below 6000.Keyword: gel filtration, lignosulphonic acids, molecular weight, peptide-precipitating ability 相似文献
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Klopfleisch R von Euler H Sarli G Pinho SS Gärtner F Gruber AD 《Veterinary pathology》2011,48(1):98-116
Studies focusing on the molecular basis of canine mammary tumors (CMT) have long been hampered by limited numbers of molecular tools specific to the canine species. The lack of molecular information for CMT has impeded the identification of clinically relevant tumor markers beyond histopathology and the introduction of new therapeutic concepts. Additionally, the potential use for the dog as a model for human breast cancer is debatable until questions are answered regarding cellular origin, mechanisms, and cellular pathways. During the past years, increasing numbers of canine molecular tools have been developed on the genomic, RNA, and protein levels, and an increasing number of studies have shed light on specific aspects of canine carcinogenesis, particularly of the mammary gland. This review summarizes current knowledge on the molecular carcinogenesis of CMT, including the role of specific oncogenes, tumor suppressors, regulators of apoptosis and DNA repair, proliferation indices, adhesion molecules, circulating tumor cells, and mediators of angiogenesis in CMT progression and clinical behavior. Whereas the data available are far from complete, knowledge of molecular pathways has a significant potential to complement and refine the current diagnostic and therapeutic approach to this tumor type. Furthermore, current data show that significant similarities and differences exist between canine and human mammary tumors at the molecular level. Clearly, this is only the beginning of an understanding of the molecular mechanisms of CMT and their application in clinical patient management. 相似文献
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分子标记是以个体间核苷酸序列变异为基础的遗传标记,是DNA水平上的遗传多样性的直接反应。分子标记技术是在DNA水平上进行多态性分析的一种技术手段,具有效率高、准确度高的特点,在绵羊育种中有着广泛的应用。分子标记技术不仅可以对绵羊的基因进行定位,而且可以对绵羊群的遗传结构进行分析,重要的是可以进行绵羊的标记辅助育种,对绵羊的育种起重要作用。作者介绍了以Southern杂交、PCR扩增、重复序列和单核苷酸多态性（SNP）为基础的分子标记技术的基本原理及优缺点,重点介绍了这些分子标记技术在绵羊的体尺、屠宰、繁殖等性状中进行标记辅助选择时的应用,揭示了在实际生产中分子标记技术对于绵羊选种与选配、提高其经济价值的重要意义,并基于目前分子标记技术在绵羊育种中的运用,以及未来分子标记技术的应用作出展望。 相似文献
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Enterobacterial repetitive intergenic consensus (ERIC) sequences are the repetitive elements present in the family enterobacteriacae. In the present study, ERIC-PCR (target ERIC sequence) was used for the molecular typing of 24 isolates of Salmonella serovars, namely abortusequi, choleraesuis, bareilly and dublin. In ERIC-PCR, seven molecular types were observed with ERIC-Cl primer, and nine molecular types with ERIC-C2 primer. When the results of both the ERIC-PCR were combined for molecular typing, 21 molecular types were observed, which indicated a high degree of discrimination. Both the ERIC primers are designed from the ERIC consensus sequence, yet they gave different profiles, indicating that they supplement each other. ERIC sequences were found to be useful targets for molecular typing. The different profiles observed appear to be due to differences in ERIC sequences and differences in inter-ERIC distance. The study indicates that ERIC-PCR is a very efficient tool for molecular typing of Salmonella species. 相似文献
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不同SDS电泳法对家蚕低分子Kunitz型抑制剂分子量鉴定的影响 总被引：1，自引：0，他引：1
采用15％SDS聚丙烯酰胺凝胶电泳和tricine—SDS聚丙烯酰胺凝胶电泳分剐对家蚕血液中低分子Kunitz型胰凝乳蛋白酶抑制剂CI-13的分子量进行了检测，SDS—PAGE结果为12．5kDa，而tricine SDS-PAGE结果为7．3kDa。另根据CI-13的氨基酸组成，算出分子量为7，113Da，这表明tricine SDS—PAGE的结果与氨基酸组成测定值接近，是适用于家蚕低分子Kunitz型抑制剂分子量鉴定的电泳方法。 相似文献