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1.
以猪血清为材料,通过磷酸乙醇胺—琼脂糖亲和层析,Sepharose 4B柱层析和Sephacryl—S300凝胶过滤,获得了猪C—反应蛋白的结晶。猪C—反应蛋白可与肺炎球菌壁C多糖发生特异的沉淀反应,这种结合是依赖钙离子的。EDTA和一些磷脂代谢产物如磷酸胆碱,磷酸乙醇胺等,能抑制猪C—反应蛋白与C多糖的结合。在SDS—聚丙烯酰胺凝胶电泳及梯度聚丙烯酰胺凝胶电泳中,猪C—反应蛋白表现出与人C—反应蛋白相同的行为,亚基是一条分子量为23.5kD的肽链,全分子的表观分子量为150kD。猪C—反应蛋白与兔抗人C—反应的蛋白的抗血清能发生免疫交叉反应。  相似文献   
2.
伤寒Vi多糖菌苗接种反应观察   总被引:3,自引:1,他引:2  
本文报告了对我国首次成功的伤寒Vi多糖菌苗进行人体接种反应观察结果,接种对象为20至54岁无伤寒病史,近年无伤寒菌苗接种史的健康人,共60名,以完全随机的方法分为两组,实验组注射30μgVi多糖菌苗,对照组注射Vi多糖菌苗的稀释液。其结果30名Vi多糖菌苗接种者注射后体温无中重反应发生,局部红肿仅有1例中反应。注射后对血压、心律没有影响。红细胞计数,白细胞计数均在正常范围,与接种前相比,无显著差异  相似文献   
3.
不同月龄婴儿接种DTP后血清中百日咳抗体水平的观测   总被引:2,自引:1,他引:1  
本文对比观察了213例2月龄、3月龄婴儿接种DTP后百日咳抗体水平的变化,探讨了母传抗体对免后抗体增长的影响。结果表明2月龄、3月龄婴儿DTP免疫后1个月和3个月血清中百日咳抗体达保护水平的百分率无显著性差异(x ̄2=0.036,p>0.9;x ̄2=0.327,p>0.5),免后1个月抗体GMT无显著性差异(t=0.17,p>0.5),免后3个月抗体GMT3月龄组高于2月龄组(t=2.22,p<0.05)。我们还发现免前抗体水平与免后1个月GMT虽有负相关(r=—0,754)的倾向,但总体上对抑制免后抗体应答不明显,因而建议将儿童DTP基础免疫的起始月龄提前至2月龄进行。  相似文献   
4.
Porins were prepared from smooth strain of Salmonella typhi 0–901 and chemotype of rough mutant of S. typhimurium Ra-30. Mice were immunized with both the porin preparations in different groups and challenged with S. typhimurium LT2–71 and S. enteritidis SH-1269. Porin immunized mice showed significant protection (P <0.01) against challenge with homologous as well as heterologous strains. Hence, the use of porins may be attempted in future to protect against salmonellosis.  相似文献   
5.
Several groups have reported protection against experimental SIV infection in macaques immunized with a whole inactivated virus vaccine. The aim of the current study was to investigate whether five macaques vaccinated with whole inactivated SIV and previously shown to be protected against challenge with two divergent strains of SIV grown on human cells could resist challenge with a subsequent homologous SIV grown on macaque cells. We show here that this same vaccine did not protect when the challenge virus was grown on primary cells of monkey origin.  相似文献   
6.
本文对吸附精制百白破混合制剂的不同配方进行了实验,结果表明,新一代吸附精制百白破混合制剂最佳配方为:精制百日咳菌苗18μgPN/ml、精制白喉类毒素为30Lf/ml、精制破伤风类毒素为10Lf/ml。由该配方组成的吸附精制百白破混合制剂,其中百日咳菌苗的毒性试验BWDU/ml、LPU/ml、HSU/ml三种指标均符合制检规程要求。其效力单位(IU/ml)超过规程要求一倍以上,精制白喉和破伤风类毒素的安全试验均符合规程要求,白类效力试验≥80-100%,破类效力试验≥0.5-4.5IU/ml。上述结果说明本文提出的配方作为新一代精制百白破混合制剂的配方是适宜和实用的。  相似文献   
7.
IntroductionBNT162b2 (BioNTech and Pfizer) is a nucleoside-modified mRNA vaccine that provides protection against SARS-CoV-2 infection and is generally well tolerated. However, data about its efficacy, immunogenicity and safety in people of old age or with underlying chronic conditions are scarce.PurposeTo describe BNT162b2 (BioNTech and Pfizer) COVID-19 vaccine immunogenicity, effectiveness and reactogenicity after complete vaccination (two doses), and immunogenicity and reactogenicity after one booster, in elders residing in nursing homes (NH) and healthy NH workers in real-life conditions.MethodsObservational, ambispective, multicenter study. Older adults and health workers were recruited from three nursing homes of a private hospital corporation located in three Spanish cities. The primary vaccination was carried out between January and March 2021. The follow-up was 13 months. Humoral immunity, adverse events, SARS-CoV-2 infections, hospitalizations and deaths were evaluated. Cellular immunity was assessed in a participant subset.ResultsA total of 181 residents (mean age 84.1 years; 89.9% females, Charlson index ≥2: 45%) and 148 members of staff (mean age 45.2 years; 70.2% females) were surveyed (n:329). After primary vaccination of 327 participants, vaccine response in both groups was similar; ≈70% of participants, regardless of the group, had an antibody titer above the cut-off considered currently protective (260 BAU/ml). This proportion increased significantly to ≈ 98% after the booster (p < 0.0001 in both groups). Immunogenicity was largely determined by a prior history of COVID-19 infection. Twenty residents and 3 workers were tested for cellular immunity. There was evidence of cellular immunity after primary vaccination and after booster. During the study, one resident was hospitalized for SARS-CoV-2. No SARS-CoV-2-related deaths were reported and most adverse events were mild.ConclusionsOur results suggest that the BNT162b2 mRNA COVID-19 vaccine is immunogenic, effective and safe in elderly NH residents with underlying chronic conditions.  相似文献   
8.
Abstract Safe, live attenuated Salmonella strains can be produced by introducing defined non-reverting mutations into the chromosome. Such rationally attenuated strains have proved to be excellent oral vaccines in several animal species and can therefore be considered as candidate vaccines against invasive salmonellosis in both animals and man. A panel of attenuating lesions is now available from which it is possible to tailor the level of attenuation and hence produce strains with different immunogenic properties. Because of the spectrum of immune responses produced by such Salmonella vaccine strains they have been utilised extensively as vectors for delivering heterologous antigens to the mammalian immune system. We have focussed on the development of a single dose oral tetanus vaccine based on attenuated Salmonella strains expressing a non-toxic, immunogenic protein derived from tetanus toxin (fragment C). Several different expression systems have been used for fragment C and candidate vaccine strains have been constructed that are capable of protecting orally immunised mice against a lethal challenge with tetanus toxin. An oral tetanus vaccine may help to reduce the mortality rate from tetanus in the developing world by overcoming the problems associated with the implementation of vaccine programmes using the current parenteral vaccine.  相似文献   
9.
流行性出血热地鼠肾细胞双价灭活疫苗的人体观察   总被引:2,自引:0,他引:2  
宋士  黄永成 《病毒学报》1993,9(2):144-151
  相似文献   
10.
Abstract The effectiveness of DNA immunization has been demonstrated in several model systems, usually following intramuscular injection of DNA in saline, or topical administration to the skin. In this study we have compared DNA delivered by three routes (intramuscular, intravenous, and intraperitoneal) and, for each route, in two vehicles (cationic liposome complex and pH sensitive liposome). These two lipid vehicles were evaluated because they are frequently used in gene therapy studies, but their immunogenicity has not been extensively studied. Each of these six combinations has been evaluated not only by assay of marker gene expression in a variety of tissues, but also by measurement of biologically-relevant parameters of immunity induction of antibodies, cytotoxic T lymphocytes, and protection against viral challenge. By both criteria (marker gene expression and induced immunity), the outcomes vary markedly among the six combinations. The combination leading to maximal marker gene expression (DNA with cationic lipid, administered i.v.) also induces detectable antibodies and CTL, and is the only one of the six combinations to induce immune responses comparable to those seen following i.m. injection of DNA in saline. However, marker gene expression can be detected in other combinations in the absence of induced immunity thus the value of marker gene expression in predicting the protection induced by a microbial antigen is questionable suggesting that, when evaluating various promoter constructs, marker gene expression may not adequately replace the direct measurement of biological outcomes.  相似文献   
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