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141.
We assessed the efficacy of a government-sponsored mass protection program in Osaka, Japan, for perinatal HBV infection in infants born to HBeAg positive HBV carrier mothers. We also evaluated the impact of optional follow-up procedures in such infants, including an evaluation of anti-HBs response and a booster dose of HBV vaccine for poor responders. The results demonstrated that this mass protection program protected 94.4% of the infants from perinatal HBV infection in the Osaka area. However, the proportion of infants with an unprotective level of anti-HBs was higher in the standard group than in the follow-up group both at 1.0 and 1.5 years of age, which was also the case for HBV events. Furthermore, the present study showed that a booster dose of vaccine in poor responders was very effective in promoting an anti-HBs response. In conclusion, we recommend that a follow-up blood test to confirm a response of anti-HBs to HBV vaccine should be performed at 4–8 weeks after the third injection of HBV vaccine in infants born to HBeAg positive HBV carrier mothers. We also recommend that a booster injection of HBV vaccine should be immediately given to poor responding infants who otherwise are at a considerable risk of developing HBV infection in late infancy.  相似文献   
142.
目的 :探讨联合菌苗防治肿瘤的作用。方法采用动物体内实验 ,动物为封闭群KM小鼠 ,菌株为 2 6 0 0 3- 2 1、4 482 4 - 3及 932 0 1- 3,瘤种为S180 。所有实验小鼠接种S180 后 ,按随机对照试验设计分成 5组 ,即三个不同的单价菌苗组、一个联合菌苗组及一个对照组 ,同期观察联合菌苗对S180 增长的影响。结果 :三个不同的单价菌苗组及联合菌苗组的平均瘤重均比对照组低 ,联合菌苗组的平均瘤重比单价菌苗组的更低 ,差异均有高度统计学意义 (P <0 .0 1~ 0 .0 0 1) ;三个不同单价菌苗组的抑瘤率分别为 5 0 .6 %、4 8.3%、4 5 .5 % ,联合菌苗组抑瘤率为 75 .0 %。结论 :实验所选用的菌苗能抑制S180 的增长 ,联合菌苗的效果更好  相似文献   
143.
从感染病毒乳鼠脑组织提取总RNA,采用RT-PCR和分子克隆技术将扩增到的G2糖蛋白基因插入含CMV启动子的pcDNA3.1/His质粒载体中,通过脂质体介导转染COS-7细胞,用SDS-PAGE、Western-blot及IFIA方法分别测定表达产物的相对分子量及特异性。结果证明获得正向插入的G2-pcDNA3.1/His重组表达质粒,表达产物的相对分子量为56ku,与理论预期大小一致,并且可与汉坦病毒H8205株的腹水抗体起特异反应。表明构建的G2-pcDNA3.1/His重组质粒所表达的蛋白为中国汉坦病毒株特有,能在哺乳动物细胞中表达并具有抗原性,重组质粒可应用于汉坦病毒的DNA疫苗研究。  相似文献   
144.
风疹易感人群婚前风疹疫苗接种预防先天性风疹综合征   总被引:1,自引:0,他引:1  
目的探讨婚前风疹易感人群风疹疫苗接种在提高孕妇对风疹的免疫力,预防先天性风疹综合征中的作用.方法对10 913例婚前风疹病毒抗体IgG阴性者给予国产风疹减毒活疫苗注射.3个月随防671例,比较风疹疫苗接种前后该地区孕妇近期风疹感染的发病率.结果818例风疹病毒抗体IgG阴性者接种后抗体转阳率为99.8%.风疹疫苗接种前后3年孕妇近期风疹感染率分别为0.37%及0.08%,有明显下降,有非常显著差异(P<0.001).结论应用国产风疹减毒活疫苗对婚前易感人群作预防接种可提高育龄妇女对风疹的免疫力,降低孕期风疹感染的发生率,是预防先天性风疹综合征及风疹致畸的有效、安全措施.  相似文献   
145.
目的 研究肿瘤相关抗原CA19-9在胃癌组织中的表达情况。方法 采用免疫组织化学方法对30例胃癌、癌旁组织、正常胃粘膜和30例胃溃疡组织中的CA19-9的表达情况进行了检测。结果 30例胃癌CA19-9阳性表达23例(76.7%,23/30)。其中胞浆和胞膜均阳性的16例(69.6%,16/23),而仅胞膜阳性5例(21.7%,5/23)。30例癌旁组织CA19-9阳性表达1例(3.3%,1/30)且为胞膜阳性。正常胃粘膜和胃溃疡组织中CA19-9表达均为阴性。在10例高分化腺癌组织中阳性4例,17例低分化腺癌组织中阳性16例,3例粘液癌全为阳性。结论 胃组织中CA19-9的表达可能成为胃癌的肿瘤标志之一,尤其适用于低分化腺癌和粘液癌,而对高分化腺癌不适合。  相似文献   
146.
目的:初步分析人源性多肽pCM-19的抗菌作用机制。方法:利用荧光素掺入破损细胞膜的原理,采用流式荧光激活细胞分析(FACScan)和扫描电子显微镜分析pCM-19对靶菌膜的作用机制。结果:FACS分析法结果显示pCM-19处理后的大肠杆菌PI着染细菌比例明显高于未处理组,并且随作用时间的延长,PI着染BL-21菌比例增大,20min时达最高水平,20min以后反而降低;扫描电子显微镜观察到pCM-19处理后的大肠杆菌有明显的表面形态学的改变,如细菌体积缩小、细菌表面出现皱缩、凹陷似有孔洞形成。结论:人源性多肽pCM-19可能作用于细菌细胞壁和(或)细胞膜,通过改变其通透性而发挥杀菌作用。  相似文献   
147.
The recent global resurgence of mumps has drawn attention to the continued need for robust mumps immunization programs. Unfortunately, some vaccines derived from inadequately attenuated vaccine strains of mumps virus have caused meningitis in vaccinees, leading to withdrawal of certain vaccine strains from the market, public resistance to vaccination, or in some cases, cessation of national mumps vaccination programs. The most widely implicated mumps vaccine in cases of postvaccination meningitis is derived from the Urabe AM9 strain, which remains in use in some countries. The Urabe AM9 vaccine virus has been shown to exhibit a considerable degree of nucleotide and amino acid heterogeneity. Some studies have specifically implicated variants containing a lysine residue at amino acid position 335 in the hemagglutinin-neuraminidase (HN) protein with neurotoxicity, whereas a glutamic acid residue at this position was associated with attenuation. To test this hypothesis we generated two modified Urabe AM9 cDNA clones coding either for a lysine or a glutamic acid at position 335 in the HN gene. The two viruses were rescued by reverse genetics and characterized in vitro and in vivo. Both viruses exhibited similar growth kinetics in neuronal and non-neuronal cell lines and were of similar neurotoxicity when tested in rats, suggesting that amino acid 335 is not a crucial determinant of Urabe AM9 growth or neurovirulence.  相似文献   
148.
Chandipura virus (CHPV) has emerged as an important pediatric encephalitis-causing pathogen with very high mortality in India. No specific vaccine or treatment is available till date. We attempted to prepare a candidate vaccine employing recombinant CHPV Glycoprotein (rGp). The Glycoprotein gene (G-gene) of CHPV was expressed using Baculovirus expression system. The rGp was purified by HPLC and used for mice immunization, 3 doses, and 4 weeks apart. One microgram rGp was found to be optimum. Sero-conversion was observed as early as 2nd week by detecting anti-CHPV IgG antibodies. Antibody titres were immunogen-concentration dependent. Intracerebral challenge of the immunized mice with 100 LD50 of the homologous strain demonstrated 90% protection. In in vitro neutralization, antibodies from the immunized mice were able to neutralize heterologous viruses. There was 60% T cell proliferation observed against rGp in immunized mice. The study shows that rGp induces both arms of immune response and represents an ideal vaccine candidate for further evaluations.  相似文献   
149.
Different immunosuppressant regimens vary in their effects on antibody responses to vaccination. The combination of prednisolone and azathioprine has only a minor effect, whereas the addition of ciclosporin attenuates protective antibody responses to influenza vaccination. The effect of sirolimus, a new immunosuppressant, on vaccine responses has been little studied. Thirty-two hepatic or renal transplant patients randomized to calcineurin inhibitor-based or sirolimus-based immunosuppression were vaccinated against influenza and pneumococcus. Following tri-valent influenza vaccination, a similar rise in antibody titer occurred in sirolimus and calcineurin inhibitor (CNI) treated patients, though sirolimus treated patients developed a 'protective' titer to more influenza antigens. The pneumococcal polysaccharide vaccine was equally effective in both groups. Hence, vaccination guidelines in place for CNI treated patients are likely to be appropriate for transplant recipients maintained on sirolimus.  相似文献   
150.
OBJECTIVE: To evaluate the user experience and acceptability of an electronic patient monitoring system. SETTING AND PARTICIPANTS: 822 Military and civilian personnel at a health clinic at a major US military headquarters used an Internet and telephone-based electronic monitoring system to report vaccination-site responses and symptoms after receiving the smallpox vaccination. Focus groups of vaccinees were conducted to help develop a survey about the experience that was distributed to 379 vaccinees (96% completion rate). RESULTS: Users of the electronic monitoring system reported that it was fast and easy to use and reported they would use a system like this again and recommend an electronic monitoring system to a friend or relative. Most users (84%) were comfortable with a physician tracking their vaccine reaction using their electronic reports, but only half (51%) were comfortable with eliminating the post-vaccination follow-up visit with their health-care provider based on their electronic reports. CONCLUSIONS: This electronic monitoring system was well received by vaccinees and allowed health-care providers to track the status of vaccinees. However, vaccinees were not comfortable replacing a physician visit with electronic monitoring, at least for the smallpox vaccination. A monitoring system like this may be useful in public health settings, such as mass vaccination or prophylaxis during a bioterrorism event, a pandemic influenza outbreak, or another public health emergency.  相似文献   
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