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131.
Horimoto  T.  Limcumpao  J. A.  Xuan  X.  Ono  M.  Maeda  K.  Kawaguchi  Y.  Kai  C.  Takahashi  E.  Mikami  T. 《Archives of virology》1992,126(1-4):283-292
Summary Heterogeneity of 9 feline herpesvirus type 1 (FHV-1) strains consisting of the prototype C27 strain, one French isolate, six Japanese isolates, and the attenuated vaccine F2 strain was examined by biological, immunological, and molecular biological methods. No significant difference was observed in virus growth and antigenic properties among the strains in Crandell feline kidney cell cultures. Hemagglutination activity was also detected in all extracts of cells infected with each strain. However, in immunoblot analysis, a virus-structural immunogenic protein with an Mr of 36 kDa was lacking in 2 strains, one of which was the vaccine F2 strain, whereas the other immunogenic proteins including three kinds of major glycoproteins were detected in all strains without differences in electrophoretic mobilities. Furthermore, when restriction endonuclease analysis was performed to examine the genomic heterogeneity of strains, the cleavage patterns with the enzymeMluI showed a genomic heterogeneity between wild and vaccine strains. In contrast, only a slight variation in the sizes of some fragments was shown with most of the 7 other enzymes used. These results indicated that the lack of the 36 kDa protein and theMluI cleavage pattern could be used as markers of the vaccine F2 strain. The specific markers are important not only to control the quality of the vaccine but also to evaluate the vaccine immunity in FHV-1 infection in cats.  相似文献   
132.
BACKGROUND: There are conflicting reports on the effect of BCG vaccination on the subsequent development of atopy and asthma. There are no data on the effects of neonatal BCG vaccination on cytokine responses of lymphocytes that are exposed in vitro to allergens. OBJECTIVES: We sought to test the hypothesis that neonatal BCG vaccination or, alternatively, evidence of an immunologic memory of this vaccination is associated with a reduced prevalence of allergic sensitization, asthma, eczema, and hay fever during childhood. METHODS: An historical cohort study was conducted among 7- to 14-year-old children who were born in 2 districts in Sydney, Australia, and whose mothers were born in southeast Asia. One district had routinely administered BCG vaccination to infants born to overseas-born mothers and the other had not. Eligible subjects were identified from birth registers. Consenting subjects completed questionnaires, performed spirometric and airway hyperresponsiveness testing, and had allergen skin prick testing and tuberculin skin testing. Blood was collected to measure total serum IgE levels and for in vitro lymphocyte culture in the presence of an extract of house dust mite, the dominant allergen in this region, and purified protein derivative of Mycobacterium tuberculosis (tuberculin). IL-4, IL-5, IL-10, and IFN-gamma were measured in the culture supernatant. RESULTS: The cohort included 309 BCG-vaccinated subjects and 442 non-BCG-vaccinated subjects. BCG-vaccinated subjects did not have a lower rate of allergic sensitization than nonvaccinated subjects. However, among the subgroup of subjects with a family history of rhinitis or eczema, BCG vaccination was associated with a lower prevalence of current asthma (defined as recent wheezing plus airway hyperresponsiveness; relative risk, 0.46; 95% CI, 0.22-0.95). BCG vaccination was also associated with lower levels of allergen-stimulated IL-10 production in vitro. Among the BCG-vaccinated subjects, the 44 (14.3%) who had tuberculin skin test reaction sizes of 5 mm or greater and the 31 (18.3%) who demonstrated an in vitro IFN-gamma response to purified protein derivative of M tuberculosis did not have lower rates of allergic sensitization and, overall, did not have a lower prevalence of allergic disease than tuberculin skin test or IFN-gamma nonreactors. CONCLUSION: We conclude that neonatal BCG vaccination has an effect on T-cell allergen responsiveness 7 to 14 years after vaccination and that among a subgroup of subjects with an inherited predisposition to allergic disease, this is associated with clinically relevant beneficial effects. The findings of this study encourage the view that external influences on the immune system in the neonatal period have consequences that extend into later childhood and influence the expression of asthma. Genetic factors are likely to modify the effect of those external factors.  相似文献   
133.
BACKGROUND: The association between nasal and bronchial symptoms, and the course of bronchial responsiveness and airway inflammation in house dust mite sensitive persistent rhinitis over a prolonged time period has not been thoroughly explored. OBJECTIVE: To determine if nasal symptoms were associated with bronchial symptoms in persistent rhinitic subjects, and to assess their bronchial responsiveness and airway inflammation in comparison to nonrhinitic, nonatopic controls. The additional impact of pollen sensitivity on the lower airways in rhinitic subjects was also addressed. METHODS: Rhinitics and controls answered telephone symptom questionnaires once every 2 weeks for 1 year. Every 3 months, exhaled nitric oxide (eNO) and bronchial responsiveness to histamine were measured. RESULTS: Thirty-seven rhinitics and 19 controls completed the study. High nasal symptom scores in rhinitic subjects were associated with bronchial symptoms (OR = 1.7, 95% CI 1.2-2.5). Bronchial hyper-responsiveness was present in 32.4% of rhinitic subjects on at least one clinical visit during the year. Pollen allergy caused seasonal variation in eNO (P = 0.03). CONCLUSION: In persistent rhinitic subjects, high nasal symptom scores were associated with bronchial symptoms, and many subjects experienced bronchial hyper-responsiveness during the year. Persistent rhinitic subjects were more at risk than healthy adults of bronchial symptoms and airway inflammation, which are likely risk factors for asthma.  相似文献   
134.
A recombinant vaccinia virus-expressing canine interferon (IFN)-gamma (vv/cIFN-gamma) was constructed. In rabbit kidney (RK13) and canine A72 cells infected with vv/cIFN-gamma, IFN activity was detected in the culture supernatants of both cell types. Canine IFN-gamma was also detected in both cell extracts by Western blot. The activity of the recombinant canine IFN-gamma in RK13 cells was higher than that in A72 cells. The vv/cIFN-gamma could not grow in A72 cells at a low multiplicity of infection, probably due to the antiviral activity of the canine IFN-gamma produced. Although exogenous IFN-gamma did not inhibit the growth of vaccinia virus, addition of anti-canine IFN-gamma serum recovered the growth of the vv/cIFN-gamma on A72 cells in a dose-dependent manner. These results suggest that the growth of vv/cIFN-gamma was inhibited by IFN-gamma produced in a paracrine and autocrine manner. In addition, the recombinant canine IFN-gamma inhibited the multiplication of canine herpesvirus, pseudorabies virus and canine adenovirus type 1 in Madin-Darby canine kidney cells. The antiviral effect of canine IFN-gamma was more effective than that of canine IFN-beta. From the present studies, we concluded the recombinant virus may be a useful suicide viral vector.  相似文献   
135.
一体化假肢是以聚合物为材料从接受腔到假腿一体成型的新型下肢假肢,它比传统型假肢更经济、美观、轻便,具有较大的应用前景。目前的相关研究主要集中在设计与制作及少量的临床研究方面。由于一体化假肢与传统型假肢在结构上的差异,有必要对其进行应力分析。本研究的目的是开展内骨架一体化假肢的生物力学研究,本研究基于内骨架一体化小腿假肢的真实几何构型,建立三维有限元模型,计算该模型在模拟Heel OH步态时相的载荷作用下的应力分布;在保持该模型的几何形状不变的情况下,建立了三个不同壁面厚度的一体化小腿假肢的有限元模型,分析壁面厚度对一体化小腿假肢应力分布的影响;通过分别赋予模型四种不同高分子聚合物的材料力学特性值,分析不同材料的一体化假肢的应力分布特点;分别对模型施加与正常步态的五个典型时相对应的载荷,分析一体化小腿假肢在各步态时相的应力分布特点。本研究结果对一体化假肢设计有指导价值。  相似文献   
136.
目的 :探讨保留部分上鼓室外侧壁鼓室成形术的临床价值。方法 :对 4例慢性化脓性中耳炎患者行保留部分上鼓室外侧壁鼓室成形术的临床资料进行回顾性分析。结果 :经随访半年 ,听力提高 10~ 2 0dB ,鼓膜外形正常 ,全部干耳。结论 :保留部分上鼓室外侧壁鼓室成形术能有效提高听力和干耳率 ,且手术安全  相似文献   
137.
目的 为了研究中国庚型肝炎病毒(HGV)非结构(NS3)区基因结构特征。方法 利用逆转录-半巢式-聚合酶链反应从河南1份HGV RNA阳性血清获得覆盖HBV NS3全长cDNA的4个片段,并克隆到pcDNAⅡ载体中,采用Sanger双脱氧末端终止法测定全部cDNA序列。结果 发现克隆到的包括HBV NS3区在内的cDNA序列和度为2137个核苷酸,编码711个氨基酸。与国内外已测定的5株全序列的相  相似文献   
138.
目的 对比应用逆行交锁髓内钉(GSH)和动力髁螺钉(DCS)内固定治疗股骨远端骨折的效果.方法 采用回顾性研究方法对我院自2000年8月~2004年10月治疗的54例股骨远端骨折病例进行对照研究,按A0分类:A1型17例,A2型14例,A3型11例,B1型2例,C1型6例,C2型3例,C3型1例.其中,DCS内固定30例,GSH固定24例.分组统计手术时间,出血量,骨折愈合时间,并发症,膝关节功能.结果 所有病例经5月~2年随访,平均9个月;骨折愈合时间为4.6月(4~9月).DCS固定组平均手术时间1.5小时(1~2.5小时).出血量105 ml(50~200 ml),骨折愈合时间平均4.7月(4~8月),并发症发生5例(发生率16.7%),根据Kolmert膝关节功能评分,优20例,良6例,可4例,优良率为86.6%.GSH固定组手术时间1.8小时(1.5~3.5小时).术中出血量平均120 ml(100~250 ml),平均骨折愈合时间5.1个月(4.5~9个月),并发症发生5例(发生率28%),根据Kolmert膝关节功能评分标准,优15例,良7例,可2例,优良率为91.7%.两组比较,结果无显著差异(P>0.05) 结论 逆行带锁髓内钉(GSH)及动力髁螺钉(DCS)均是治疗股骨远端骨折的较好方法,但各有其最佳适应症.选择好适应症以及术者技术熟练有利于骨折愈合及关节功能恢复.  相似文献   
139.
近来发现Wnt信号通路对个体发育和肿瘤生成具有重要作用[1-2].为进一步探讨Wnt通路在胶质瘤中是否存在表达异常及其在胶质瘤生成中的作用,我们采用RT-PcR、组织芯片免疫组织化学染色以及蛋白印迹法,对人脑胶质瘤Wnt2通路相关因子的表达变化及其意义进行了分析.  相似文献   
140.
免疫磁性海藻酸钠载药纳米微球的制备与评价   总被引:6,自引:0,他引:6  
靶向治疗系统是目前研究的热点,用微乳化-离子交联方法制备包覆阿霉素的碳包铁/海藻酸钠复合纳米微球,以水溶性碳二亚胺为交联剂,将载药微球与单抗Hab18连接,制备出了免疫磁性药物纳米微球.对该免疫磁性微球的理化性能进行了表征,同时检测了免疫磁性微球中抗体的活性和免疫磁性微球与靶细胞的体外结合情况,结果表明,免疫磁性药物纳米微球平均粒径约为171.2nm,外观为球型,铁含量为14.6%,载药量为10.8%,且具有强磁响应性和长时间药物缓释效果.同时在体外该微球能够与靶细胞特异性结合.这种免疫磁性药物纳米微球有望成为一种优良的靶向肿瘤药物载体.  相似文献   
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