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11.
J亚群禽白血病病毒gp37基因的克隆和序列分析   总被引:1,自引:0,他引:1  
近两年我们从国内不同省份先后分离和鉴定了8株J亚群禽白血病病毒(ALV-J),并对其中的5株进行了gp37基因的克隆和序列分析,结果表明,我们分离的5株ALV-J之间的同源性为94.6%-99.0%;与国内最早分离的SD9901,SD9902和YZ9901等毒株之间的同源性分别为95.3%-98.5%,95.6%-99.0%和94.9%-98.6%;与国际最先报道的原型株HPRS-103之间的同源性为93.4%-95.1%;与其它国外毒株的同源性为92.7%-96.8%。这表明我国ALV-J的gp37基因正在不断发生变异,但相对于gp85基因的变异性要小。  相似文献   
12.
Larval antigen of Hyalomma anatolicum anatolicum, the vector of Theileria annulata, was purified by two-step affinity chromatography using anti-tick gut-specific rabbit IgG and IgG from immunized cattle. The purified antigen showed the presence of a single polypeptide of 37 kDa (GHLAgP) on SDS-PAGE. Two groups (I and II) of naive crossbred calves (Bos taurus × B. indicus) were immunized with 1 mg of GHLAgP in three divided doses. Immunized calves of group I were also infected with a sublethal dose of T. annulata along with a group of non-immunized calves (group III). Animals in groups I, II, III as well a control group (group IV) were challenged with live nymphs of H. a. anatolicum on the 10th day of immunization. There was a significant reduction in the number of emerging adults of 56.9% ± 1.67% in calves of group I (p < 0.01) and 63.09% ± 1.26% in calves of group II (p < 0.001) compared to the controls. The calves of groups I and II showed antibody responses to tick antigen up to day 70 post immunization. Infection with T. annulata was determined in the salivary glands of adult ticks that developed from the nymphs used for challenge infection. In ticks taken from group I calves, there was a 75.0% ± 0.00% infection compared with only 85.0% ± 2.88% infection in ticks taken from calves of group III. Using PCR, a lower infection (83.33% ± 3.33%) was detected in ticks that developed from calves of group I compared with calves from group III (90.00% ± 2.88%). The ground-up tick supernatants (GUTS) of the ticks taken from calves of group III yielded higher infection rate and exhibited higher infectivity titre in in vitro infection assay of bovine mononuclear cells than the GUTS of the ticks taken from calves of group I. The results suggest a partial reduction in growth rate of T. annulata in ticks feeding on calves immunized with GHLAgP.  相似文献   
13.
中晚熟辣椒湘椒37号是以湖南一地方牛角椒自交系9506—6为母本,以由以色列引进的牛角椒经多代定向分离筛选的优良株系9202为父本配制成的一代杂种。果实长牛角形,纵径16~18cm,横径3.2cm,肉厚0.4cm,平均单果质量45g,果面光滑顺直,青熟果绿色,辣味适中,耐贮运,667m^2产量2400~4000kg。适宜长江流域或河南、安徽等地麦茬夏秋中晚熟丰产栽培。  相似文献   
14.
【目的】获取ASFV p37蛋白,并制备抗ASFV p37蛋白的多克隆抗体,为ASFV p37蛋白结构和功能研究提供材料。【方法】应用生物信息学工具对ASFV HLJ/2018(GenBank登录号:MK333180.1)p37蛋白进行分析,设计合成p37基因,并构建pET32a-p37重组质粒。将重组质粒转化大肠杆菌BL21(DE3)感受态细胞,经IPTG诱导表达后,通过SDS-PAGE对重组蛋白的可溶性进行分析。收集菌体进行超声破碎,分离沉淀并使用8 mol/L尿素变性后离心,用0.45μm滤膜过滤离心后的上清,使用镍亲和层析柱纯化蛋白,通过SDS-PAGE、Western blotting对其纯化效果及特异性进行验证。将纯化后的p37蛋白按照50μg/只免疫小鼠,制备抗ASFV p37蛋白多克隆抗体。利用间接ELISA方法测定制备的多克隆抗体效价;通过Western blotting、间接免疫荧光试验检测该多克隆抗体的特异性。【结果】生物信息学分析表明,p37蛋白为稳定亲水性蛋白,无跨膜区和信号肽。二级结构主要含有α-螺旋(45.28%)、延伸链(15.09%)、无规则卷曲(31...  相似文献   
15.
根据编码rAs37的已知基因序列设计并合成1对引物,应用PCR技术从猪蛔虫感染性虫卵的cDNA中扩增编码rAs37的部分基因,克隆入pGEX-KG表达载体,转化入E.coli DH5α感受态细胞,经含氨苄青霉素琼脂平板筛选,小量抽提质粒进行酶切、PCR及DNA测序鉴定.然后阳性重组质粒转化入E.coli BL21-CodonPlus, IPTG诱导,表达产物经SDS-PAGE和Western-blot分析鉴定.结果显示,扩增的rAs37基因与GenBank中相应基因序列(AB078971)的同源性达100%,表达的rAs37融合蛋白表观相对分子质量约为60 000,且可被兔抗猪蛔虫免疫血清识别.说明所获得的表达蛋白质具有一定的反应原性,为下一步利用重组蛋白建立猪蛔虫早期诊断方法和研制猪蛔虫的亚单位疫苗奠定了基础.  相似文献   
16.
超级稻楚粳37号肥料减量增效试验研究   总被引:1,自引:0,他引:1  
以超级稻楚粳37号为试验材料,研究了不同肥料减量处理对水稻产量的影响。结果表明,在楚粳37号高产栽培过程中,适当降低化肥使用量(减量30%),不仅能确保高产,而且节本增效。  相似文献   
17.
水稻新品种吉农大37是以吉农大2号为母本,以通211为父本进行有性杂交后经系谱法选育而成.两年区域试验和1年生产试验平均产量分别为9 057.2 kg/hm2和8 946.6 kg/hm2,分别比对照品种长白9号增产9.2%和5.8%.该品种2009年1月通过吉林省农作物品种审定委员会审定,其主要特点是高产、抗病.该品种适宜吉林省中早熟稻作区种植,特别适宜在吉林省长春、四平、通化、松原地区种植.  相似文献   
18.
Leaf rust, caused by Puccinia triticina, is considered one of the most important diseases of wheat. In South Africa the genes Lr29, Lr34, Lr35 and Lr37 confer effective resistance to leaf rust, qualifying them for use in cultivar improvement. To study possible secondary effects of these genes, a collection of BC6 lines containing each of the genes singly, was evaluated for breadmaking quality. The recurrent parent Karee, and Thatcher NILs used as resistance donors in the primary crosses, as well as Thatcher, were included as checks. The presence of Lr29, Lr34, Lr35 and Lr37 caused a significant increase in flour protein and water absorption. For most of the other characteristics the NILs performed statistically similar to the recurrent parent. Some sib lines performed significantly better than others, emphasising the value of selecting for improved quality among backcross lines. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
19.
[目的]观察3种猫爪草的醇提物及猫爪草各不同极性部位对标准结核菌株和耐药菌株的体外抑菌效果。[方法]采用绝对浓度法,进行3种猫爪草70%乙醇提取物和猫爪草醇提物经萃取分离得到的4个极性不同部位对结核分支杆菌(H37RV)和耐药菌株的药物敏感试验。[结果]3种猫爪草(4 mg/ml)对标准菌株和耐药菌株均有抑菌作用,且石油醚萃取部位抑菌浓度最低为2 mg/ml。[结论]猫爪草具有明显的体外抗耐药结核作用,以石油醚萃取部位抑菌效果最佳。  相似文献   
20.
AIM: To explore the effects of Mcl-1 signal pathway blockers on Mcl-1 expression, macrophage apoptosis and Mycobacterium tuberculosis in the model of mice infected with Mycobacterium tuberculosis H37Rv. METHODS: A mouse infection model was established by intraperitoneal injection of H37Rv suspension. The signaling pathway blockers AG490, PD98059 and LY294002 for JAK/STAT, MAPK and PI3K, respectively, were intraperitoneally injected into the mice infected with H37Rv. Cell acid-fast staining was used to observe whether the mouse peritoneal macrophages infected with H37Rv were successfully established. Immunocytochemical method was employed to detect Mcl-1 expression in the mouse peritoneal macrophages infected with H37Rv. The apoptotic rate in each group was measured by flow cytomerty. The scavenging capacity of apoptotic macrophages against H37Rv was determined by Mycobacterium tuberculosis colony counting. RESULTS: The result of cell acid-fast staining revealed the existence of dispersive arrangement of red short antiacid Mycobacterium tuberculosis within infected macrophages. The result of cell immunocytochemistry showed strongly positive expression of Mcl-1 protein in H37Rv infection group, AG490 treatment group and LY294002 treatment group, weakly positive expression of Mcl-1 protein in PD98059 treatment group, and negative expression of Mcl-1 protein in control group. The result of flow cytometry found that the macrophage apoptotic rate in H37Rv infection group was higher than that in control group, while that in PD98059 treatment group was high than that in other groups with statistically significant differences (P<0.05). The result of Mycobacterium tuberculosis colony counting showed that PD98059 treatment had the most significant inhibitory effect on H37Rv strain. CONCLUSION: Mcl-1 signaling pathway blockers increase the apoptotic rate of macrophages infected with Mycobacterium tuberculosis H37Rv and inhibit the growth of Mycobacterium tuberculosis by inhibiting the signaling pathways of JAK/STAT, MAPK and PI3K, among which the MAPK has the most obvious interfering effect on Mcl-1, and leads to the highest apoptotic rate of infected macrophages and the strongest bacteriostasis.  相似文献   
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