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81.
变形链球菌表面蛋白和葡糖基转移酶基因疫苗对唾液变形链球菌和牙菌斑的影响 总被引:2,自引:0,他引:2
目的 了解变形链球菌表面蛋白和葡糖基转移酶基因疫苗单独及联合免疫对定菌鼠唾液变链菌和牙面菌斑的影响。方法 2 8d龄 Wistar大鼠 3 6只 ,随机分为 pc DNA3 - pac组、pc DNA3 - gtf B组、pc DNA3 - pac联合pc DNA 3 - gtf B组、变形链球菌灭活全菌组、pc DNA3空载体组和 PBS液组 ,进行三次双侧颌下腺腺周注射免疫 ,建立定菌鼠模型 ,作诱龋实验 3个月。唾液变链菌计数和菌斑计分。结果 唾液变链菌菌落计数和牙面菌斑计分在 pc D-NA3与 PBS组最高 ,其次为单基因疫苗免疫组 ,联合基因疫苗和灭活全菌细胞免疫组最低 ,各组间有显著性差异 ( P<0 .0 5 )。结论 pc DNA3 - gtf B和 pc DNA3 - pac具有明显的免疫抑菌作用 ,联合基因疫苗免疫优于单基因疫苗 相似文献
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83.
Dengue is a mosquito-borne viral disease caused by four antigenically distinct serotypes of dengue viruses (DENVs). This disease, which is prevalent in over a hundred tropical and sub-tropical countries of the world, represents a significant global public health problem. A tetravalent dengue vaccine capable of protecting against all four DENV serotypes has been elusive so far. Current efforts are focused on producing a tetravalent vaccine by mixing four monovalent vaccine components. In this work, we have utilized a discrete carboxy-terminal region of the major DENV envelope (E) protein, known as domain III (EDIII), which mediates virus entry into target cells and contains multiple serotype-specific neutralizing epitopes, to create a chimeric tetravalent antigen. This antigen derived by in-frame fusion of the EDIII-encoding sequences of the four DENV serotypes was expressed using a replication-defective recombinant human adenovirus type 5 (rAdV5) vaccine vector. This rAdV5 vector induced cell-mediated immune responses and virus-neutralizing antibodies specific to each of the four DENVs in mice. Interestingly, anti-AdV5 antibodies did not suppress the induction of DENV-specific neutralizing antibodies. We observed that anti-AdV5 antibodies in the sera of immunized mice could promote uptake of a rAdV5-derived reporter vector into U937 cells, suggesting that pre-existing immunity to AdV5 may in fact facilitate the uptake of rAdV5 vectored vaccines into antigen presenting cells. This work presents an alternative approach to developing a single component tetravalent vaccine that bypasses the complexities inherent in the currently adopted four-in-one physical mixture approach. 相似文献
84.
A deceased donor (DD) allocation system incorporating net life survival benefit has been proposed. In this system, many kidneys will be shifted to younger recipients, thereby decreasing their waiting times. The goal of this study was to determine the potential effects of altering waiting times on the likelihood of live donor kidney transplantation (LDKT). We analyzed 93,727 waiting list candidates to determine the association of various patient factors with likelihood of LDKT. The proportion of patients receiving LDKT was compared by the median DD waiting time at that patient's transplant center for someone of that patient's age category and race. LDKT was consistently higher as waiting times became longer. After adjusting for all other factors associated with likelihood of LDKT, waiting time remained a significant, independent predictor. Patients with the longest DD waiting times had 2.3-fold higher odds of LDKT (95% CI 2.11-2.58, p < 0.001). In planning the new DD allocation policy, we must account for resulting alterations in LDKT. It is possible that shifting DD kidneys to younger recipients may decrease LDKT or shift it to older recipients, net effects not consistent with the goal of net life survival benefit. 相似文献
85.
研究发现,肿瘤的生长和转移依赖于血管的生成,如果抑制肿瘤新生血管的形成就可以有效抑制肿瘤细胞的生长和转移.越来越多的证据表明,以血管相关抗原为靶点的疫苗可以引发机体产生特异性细胞或体液免疫反应,抑制血管的形成,从而起到阻止肿瘤细胞生长和转移的作用.目前,针对肿瘤血管生成的疫苗治疗已成为肿瘤研究的热点及肿瘤治疗的新策略.本文就目前所进行的抗肿瘤血管生成的疫苗研究情况作一综述. 相似文献
86.
87.
FLAIR序列脑室内脑脊液搏动伪影(VCSFA)的表现及初步分析 总被引:1,自引:0,他引:1
目的探讨FLAIR序列脑室内脑脊液搏动伪影的表现及其与年龄、性别、脑室大小的关系。方法对100例正常成人行头颅MR检查,并对FLAIR序列脑室内脑脊液搏动伪影(VCSFA)进行观察统计分析。结果VCSFA表现为脑室内轻微或明显高信号,在Ⅲ,Ⅳ脑室最常见,在不同年龄组存在明显差异(P<0.05),VCSFA组Ⅲ,Ⅳ脑室左右径大于无VCSFA组(P<0.05)。结论VCSFA是由反转延迟造成的,随着年龄增长及脑室增大,VCSFA出现频率增加,与性别无关。 相似文献
88.
增强抗原呈递功能的树突状细胞疫苗 总被引:1,自引:0,他引:1
树突状细胞(DC)疫苗的研究已成为当前肿瘤免疫治疗的一大热点。随着对DC的不断认识,其强大的功能可塑性为发展增强其抗原呈递功能的DC疫苗提供了新思路,现就DC疫苗增强其抗原呈递功能的种种途径进行综述。 相似文献
89.
Z. Peng Q. Liu Q. Wang E. Rector Y. Ma R. Warrington 《Clinical and experimental allergy》2007,37(7):1040-1048
BACKGROUND: Immunotherapy with anti-IgE antibodies for treatment of allergy is promising but a short half-life and extremely high cost limit its application. OBJECTIVE: We sought to develop IgE vaccines that induce longer-lasting auto-antibodies to neutralize self-IgE as an alternative therapy. METHODS: The vaccine was made by conjugating three synthetic peptides corresponding to human IgE receptor-binding sites to a carrier, hepatitis B surface antigen. To test the immunogenicity of the vaccine, rats were immunized with the vaccine or hepatitis B surface antigen as control. Serum IgG titres to human IgE and the IgE of other species were measured. The inhibition by rat antisera of the binding of human IgE to its receptor was assessed by ELISA, flow cytometry analysis, and passive cutaneous anaphylaxis (PCA), and its ability to recognize receptor-bound IgE was examined. The in vivo effect of the vaccine was evaluated in trichosanthin-sensitized mice and rats. In the preventative study, vaccination started before sensitization commenced, while in the treatment study, vaccination started after sensitization. Sensitized mice and rats receiving injections of the carrier served as controls. Trichosanthin-specific IgE was measured using PCA. RESULTS: Sera from vaccine-immunized rats contained high titre antibodies that reacted with soluble and plate-bound but not with receptor-bound human IgE; they also reacted with mouse, rat, and dog IgE. Furthermore, the sera inhibited the binding of human IgE to its receptor in a dose-dependent manner. In preventative and treatment studies, serum trichosanthin-specific IgE levels were significantly reduced in vaccinated groups compared with controls. CONCLUSION: Antibodies against self-IgE can be induced by IgE peptide-based vaccines, which are effective in preventing the increase of IgE and in down-regulating IgE in sensitized animals. 相似文献
90.
采用微量乙肝疫苗(总剂量为6μg)对HBV高流行区居民进行随机对照研究,免疫Ⅰ组(疫苗<8℃保存)T12抗体阳转率和保护率分别为90.8%和87.0%,和对照组相比,差异显著(P均<0.001);和常规剂量(总剂量90μg)比,其抗体阳转率和保护率基本相同。提示HBV高流行区可用微量乙肝苗代替常量乙肝苗进行预防接种。免疫Ⅰ组和免疫Ⅱ组(乙肝疫苗室温保藏28℃±)免疫效果和保护率基本相同,认为室温条件下乙肝疫苗6个月内效价不变。 相似文献