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51.
Vaccination against the cat flea Ctenocephalides felis felis   总被引:1,自引:1,他引:0  
Non-chemical control of haematophagous parasites is a desirable goal. We report here on the use of concealed antigens from the major digestive organ of the cat-flea as vaccine components. Rabbits were immunized with various antigens from cat flea midguts, and immunoglobulin from these rabbits was fed to cat fleas in an artifical feeding system. Antibody produced against soluble antigens from the midguts of fed fleas was able to kill fleas in this system. Dogs were then immunized with various antigen preparations, and challenged for a week with live fleas. Significantly fewer live fleas were recovered from dogs immunized with fed midgut supernatant, and recovered live female fleas produced significantly fewer eggs. This study indicates the possibility of vaccination as a means of control of flea, and possibly other blood sucking insect populations.  相似文献   
52.
水痘疫苗接种的成本效益   总被引:4,自引:0,他引:4  
水痘是一种常见的急性、高传染性的疾病 ,可感染儿童、成人。 1974年日本首先研制成功Oka株水痘减毒活疫苗 ,1984年世界卫生组织批准水痘减毒活疫苗用于婴幼儿预防接种 ,许多国家陆续开展了水痘疫苗预防接种 ,不仅能取得良好的防病效果 ,而且可较大地减轻疾病负担。对儿童、青少年、成人、育龄期妇女和免疫功能抑制患者分别进行的经济学评价表明 ,接种水痘疫苗具有较好的成本效益结果。  相似文献   
53.
新生儿重组酵母乙肝疫苗接种免疫的研究   总被引:1,自引:0,他引:1  
目的:探讨重组酵母乙肝疫苗新生儿接种后抗体应答持续时间,强化复种的必要性。方法:常规对新生儿0d(出生后当天)、1月、6月接种重组酵母乙肝疫苗后检测抗体应答情况,再随机分两组,一组为强化组,一组为常规组,并随访其5年的抗体应答情况。结果:新生儿常规接种法,于12个月后有一明显抗体应答下降期(0d、1月、6月、12月),强化组乙肝表面抗体形成率高,持续时间均高于常规接种法。结论:新生儿乙肝疫苗0d、1月、6月、12月接种法有较好的远期保护效果,对现有的0d、1月、6月新生儿乙肝疫苗常规接种法,有强化接种的必要。  相似文献   
54.
The epidemiological situation calls for almost yearly changes in the antigenic composition of influenza vaccine, thus necessitating fresh licensing procedures. Since the time for bringing a new vaccine onto the market should be relatively short, the following work of all parties involved must be done expeditiously: 1) WHO recommendations on new virus strains and their subsequent adaptation by the EEC (February/March); 2) Distribution of the new virus strains to the International Reference Centers for Influenza in the UK and USA (February/ March); the centers later issue reference materials for the determination of the haemagglutinin antigen concentration (April/May); 3) Production and testing of seed virus by manufacturers, as well as validation of the producer's inactivation process for the new virus strains (May/June); 4) Licensing of the vaccines by the National Control Authority (Paul-Ehrlich-Institute) (June/July); in the case of previously licensed products, the procedure is limited essentially to the approval of the detailed protocol of production and tests on the new virus strains, clinical studies not being required before licensing because of a lack of time; 5) Paul-Ehrlich-Institute's test for batch release, according to Directive 89/342/EEC, besides protocol approval, conducts material testing of the endotoxin and antigen content of each vaccine lot; the assay for the antigen quantification is especially laborious and sometimes must be repeated because of test invalidity.  相似文献   
55.
作者采用PCR方法克隆了我国海南省FCC1/HN株P190抗原两个保守区基因,分别定名为P190CRI和P190CRV。基因片段经纯化后连接到pUC18载体中进行DNA序列分析,结果显示:除了P190CRV中有5个碱基变换外,其余序列均与MAD20型序列一致。经序列分析的两个基因片段分别与pGEX-2T载体连接,经双酶切鉴定后转化感受态JM109(DE_3)大肠杆菌进行高效融合表达,并且用Sepharose 4B-谷胱甘肽层析柱进行亲和纯化,结果为:两个插入基因片段均得到高效融合表达,经一步亲和纯化后就取得高纯度的重组蛋白。  相似文献   
56.
Purpose: We examined whether bone marrow-derived dendritic cells (DCs) could induce antitumor immunity when a chemotherapeutic drug was added. Methods: CT26 (a murine colon cancer cell line syngeneic with BALB/c) and CT26-bearing mice were treated with mitomycin C (MMC) intraperitoneally (i.p.). Next, mice immunized with a coinjection of DCs and MMC-treated CT26 (i.p.) were given an intradermal inoculation of CT26. Finally, CT26-bearing mice were treated with MMC (i.p.) with or without DCs, given peritumorally. Results: Although the inoculated tumor was not rejected in the control mice, CT26 was rejected in 50% of the mice injected with MMC alone. Apoptosis was observed in the MMC-treated CT26 cells in vitro and in vivo. Immunization with DCs and apoptotic CT26 cells, but not with apoptotic CT26 alone, gave protection against tumor challenge in 7 of 13 mice. A significantly higher level of cytotoxic T-cell activity and interferon-γ production was seen in the protected mice. When MMC (i.p.) treatment was followed by peritumoral DC injection in the CT26-bearing mice, remarkable therapeutic effects were observed. Conclusion: DCs can collaborate with chemotherapy-induced apoptotic tumor cells and elicit improved antitumor immunity, probably through the acquisition of tumor-associated antigens from apoptotic tumor cells. Received: January 7, 2002 / Accepted: September 3, 2002 Acknowledgments. We thank Dr. Kazuo Kinoshita for his useful advice on using flow cytometry. This research was partly supported by the Ministry of Education, Culture, Sports, Science and Technology (No. 11671160). Reprint requests to: S. Yamasaki  相似文献   
57.
目的 观察小剂量卡介苗(BCG)、丝裂霉素C(MMC)交替灌注预防浅表性膀胱癌术后复发的疗效和安全性。方法 回顾性分析自2000年5月~2001年6月的45例浅表性膀胱癌患的临床资料,29例行膀胱部分切除术,16例行经尿道膀胱肿瘤电切术(TuRBt),术后定期应用卡介苗60mg、丝列霉素C 10mg交替膀胱灌注,每周1次共6次,间歇3个月,再每月1次,持续12个月。其中Ta、T1期22例、T2期23例。结果 所有病人随访12~24个月,45例患中,共有2例复发,均为TURBt后T2病人,总有效率95.2%,无全身不良反应,仅2例应用BCG后出现轻度膀胱刺激症状。结论 小剂量MMC、BCG交替膀胱内灌注,预防浅表性膀胱癌术后复发,效果好、病人耐受性强、副作用小。  相似文献   
58.
Cattle were vaccinated either with a single recombinant tick antigen, Bm86 or with a combination of two recombinant antigens, Bm86 and Bm91 from the tick Boophilus microplus . In three experiments, the responses of cattle to subsequent challenge with the tick were assessed. The addition of the Bm91 antigen enhanced the efficacy of the vaccination over that with Bm86 alone to a statistically significant degree. Moreover, co-vaccination with two antigens did not impair the response of cattle to the Bm86 antigen. Finally, responses of individual cattle to the two antigens were independent. All of these results may be relevant to the increase in efficacy expected from a dual antigen vaccine.  相似文献   
59.
江苏省肾综合征出血热单价灭活疫苗中期免疫效果观察   总被引:5,自引:2,他引:3  
观察HFRS单价灭活疫苗中期免疫效果。方法:采用IFAT法及MCPENT法检测荧光抗体及中和抗体。结果:3个试区加强接种人数分别为4052、4407和6354人。加强后,Ⅰ型苗荧光抗体阳性率为72.73%,GMT为14.14;中和抗体阳性率为54.55%,GMT为6.67。D型苗荧光抗体阳性率为75.00%,GMT为11.85;中和抗体阳性率为60%,GMT为9.44。加强后1年,Ⅰ型苗年均保护率为65.52%,Ⅱ型苗则为94.24%。同期,Ⅰ型苗荧光抗体阳性率维持在40%,中和抗体维持在35.00%;Ⅱ型苗荧光抗体阳性率降至10.34%,中和抗体维持在53.85%。结论:两型疫苗均有较好的中期防病效果。  相似文献   
60.
Inactivated severe acute respiratory syndrome-associated coronavirus (SARS-CoV) has been tested as a candidate vaccine against the re-emergence of SARS. In order to understand the efficacy and safety of this approach, it is important to know the antibody specificities generated with inactivated SARS-CoV. In the current study, a panel of twelve monoclonal antibodies (mAbs) was established by immunizing Balb/c mice with the inactivated BJ01 strain of SARS-CoV isolated from the lung tissue of a SARS-infected Chinese patient. These mAbs could recognize SARS-CoV-infected cells by immunofluorescence analysis (IFA). Seven of them were mapped to the specific segments of recombinant spike (S) protein: six on S1 subunit (aa 12-798) and one on S2 subunit (aa 797-1192). High neutralizing titers against SARS-CoV were detected with two mAbs (1A5 and 2C5) targeting at a subdomain of S protein (aa 310-535), consistent with the previous report that this segment of S protein contains the major neutralizing domain. Some of these S-specific mAbs were able to recognize cleaved products of S protein in SARS-CoV-infected Vero E6 cells. None of the remaining five mAbs could recognize either of the recombinant S, N, M, or E antigens by ELISA. This study demonstrated that the inactivated SARS-CoV was able to preserve the immunogenicity of S protein including its major neutralizing domain. The relative ease with which these mAbs were generated against SARS-CoV virions further supports that subunit vaccination with S constructs may also be able to protect animals and perhaps humans. It is somewhat unexpected that no N-specific mAbs were identified albeit anti-N IgG was easily identified in SARS-CoV-infected patients. The availability of this panel of mAbs also provided potentially useful agents with applications in therapy, diagnosis, and basic research of SARS-CoV.  相似文献   
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