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11.
本文对81例乙型肝炎病人的肝活检组织进行了电镜观察,发现HBsAg的阳性率达93.8%。电镜下,HBsAg细丝不仅有一般的管状细丝型,还有分枝管型和管泡型,而且CAH病人肝组织不易找到HBsAg丝(易见者仅9%),CPH,CLH则多数(79.5%)为易见及可见,二者有高度显著性差异(P<0.01)。  相似文献   
12.
Permissive herpes simplex virus (HSV) infection in tissue culture results in host cell destruction. Latent HSV infection in vivo occurs in neurons of peripheral sensory ganglia (PSG) and it therefore can not take place in neurons in which the virus has completed a lytic replication cycle similar to that present in vitro. Our hypothesis, based on experimental data and observations in humans, suggests that establishment of latent infection and reactivation of HSV-1 does not involve neuronal cell loss. Latency is established in neurons in which the virus does not replicate and is determined, in part, by the tissue levels of a herpes transactivating protein (Vmw65) that is a component of the viral tegument. We also suggest that reactivation of latent infection does not involve destruction of neurons and is due to replication of virus at the peripheral mucocutaneous tissues to where virus or viral DNA have been transported from the nervous tissue. Alternatively, reactivation is initiated in the PSG using a replication cycle which does not involve irreversible damage to neurons. This model explains the lack of damage to neurons which continue to serve as permanent reservoirs of latent virus for the entire life of the host.  相似文献   
13.
本文采用聚丙烯酰胺凝胶等电聚焦电泳(IEF),借助园盘电泳仪的简易装置,对正常 B 型G6PD 及变异型 G6PD 进行分析,获得了满意效果。  相似文献   
14.
This paper outlines the impact of granulocyte‐colony stimulating factor (G‐CSF) used as a single modality therapy in 17 patients with secondary autoimmune neutropenia (S‐AIN) who had been treated a multiple number of times previously. Fifteen of these patients had demonstrable antineutrophil antibodies and two had cellular S‐AIN with haemopoietic inhibitory T‐cells present in the marrow. Prior to treatment, all had had problems with infection. All patients responded within 7 days of commencement of treatment. Provided G‐CSF neutrophil counts were maintained above 1 × 109/l, no further infections occurred. This was achievable by using G‐CSF administered as infrequently as once every 8 days. Eight of the 17 patients remained on G‐CSF, although five switched to the glycosylated form because of side‐effects. None have developed osteoporosis despite 47.29 patient years of total experience with G‐CSF. In conclusion both glycosylated and nonglycosylated G‐CSF can be used effectively in treating AIN on a long‐term basis.  相似文献   
15.
The advent of recombinant DNA technology has led to the identification in the DNA of normal animal cells of over 30 proto-oncogenes that are homologous to retroviral transforming genes. One of these encodes a protein kinase (pp60c-src) of unknown function, that is preferentially synthesized in brain and neural retina. Here the expression of pp60c-src in the peripheral nervous system was examined in sensory neurons from chick dorsal root ganglia with antisera raised against the transforming protein of Rous sarcoma virus (pp60v-src) expressed in Escherichia coli carrying the cloned v-src gene. This antiserum recognizes pp60c-src specifically in normal chicken cells. Western immunoblotting showed that dorsal root ganglia of stage 30 (day 6.5) chick embryos contained elevated levels of pp60c-src. Immunoperoxidase staining of neuron-enriched cultures prepared from chick dorsal root ganglia showed pp60c-src immunoreactivity in cells with neuronal morphology; flat, fibroblastic cells contained no detectable immunoreactivity. Indirect double immunofluorescence with pp60src antibodies and monoclonal antibodies against the 200-kD subunit of neurofilament protein confirmed that the cells expressing pp60c-src were neurons. Ninety-six percent of the neurofilament-positive cells were immunoreactive with pp60src antibodies, and conversely, all pp60c-src-positive cells were immunoreactive with neurofilament antibodies. pp60c-src immunofluorescence appeared to be distributed over the cell body, processes, and growth cones. These results clearly demonstrate that pp60c-src is a product of neurons and is expressed in sensory neurons in culture.  相似文献   
16.
目的探讨复方丹参注射液联合干扰素治疗慢性乙肝患者的疗效。方法110例慢性乙肝患者,按随机方法分成①对照组30例,应用普通保肝药物治疗,疗程6个月;②丹参组30例,应用复方丹参注射液(每ml含丹参、降香各1g)30ml加入10%葡萄糖溶液300ml中静脉注射1个月;③IFN组30例,应用IFN—α 3MU,隔日一次肌内注射,3个月;④联合组20例,应用复方丹参注射液30ml加10%葡萄糖溶液300ml静脉注射1个月,IFN-α 3MU,隔日一次肌内注射,3个月。丹参组,IFN组和联合组保肝药物治疗同对照组。四组病例在性别、年龄、病程,治疗前肝功能等方面均无统计学差异。治疗前检测肝功能,肝炎病毒标志,血清HA、IV—C、PCI—Ⅱ,部分病例进行肝穿病理检查。治疗开始后每月检测肝功能,3个月(治疗后)和6个月(随访时)时检测血清HA、IV—C、PCⅢ及乙肝病毒标志,治疗后1年行肝穿病理检查。结果治疗前四组患者血清HA、PCⅢ、IV—C水平无统计学差异;治疗后丹参组、IFN组、联合组血清HA、FCⅢ、IV—C水平较治疗前及对照组有不同程度的降低。结论复方丹参注射液联合IFN治疗可使血清HA、PCⅢ、IV—C有明显下降,肝组织病理改变明显改善,为目前有效的慢性乙肝治疗措施。  相似文献   
17.
The aim was to determine whether the immunogenicity of an investigational hepatitis B vaccine (spHB) is at least as high as that of a licensed control vaccine, Engerix B®, and to evaluate its safety before inclusion in new pediatric combination vaccines. Two randomized, controlled, blind-observer, Phase 3 trials were performed: one in Argentina (344 participants aged 10–15 years, 10 μg HBsAg/dose) and one in Uruguay (344 participants aged 16–45 years, 20 μg HBsAg/dose). Both vaccines were given in a 0, 1, 6 month schedule to all participants with a baseline anti-Hep B antibody titer <0.6 mIU/mL. Antibody titers were measured pre-dose 1, 1 month after dose 2, pre-dose 3, and 1 month after dose 3. Statistical non-inferiority analyses were performed on seroprotection rates (SP) post-dose 3 (% with anti-Hep B titers ≥10 mIU/mL; delta non-inferiority limit of −10%). In both studies, SP for the spHB vaccine was 100% and the spHB vaccine was non-inferior in terms of SP to the licensed control vaccine. GMTs post-dose 3 were approximately 1.8- and 4.1-fold higher for spHB in the 10–15 year and 16–45 year age groups, respectively. Reactogenicity was low for each vaccine, after each dose. This highly immunogenic hepatitis B candidate vaccine was selected for further investigation as a component of new pediatric combination vaccines.  相似文献   
18.
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   
19.
Tick-borne encephalitis (TBE) virus is an important human pathogenic flavivirus that is endemic in Europe and Asia. The disease can be effectively prevented by inactivated vaccines and vaccination breakthroughs (VBTs) are rare. We investigated the characteristics of antibody responses in such VBTs in comparison to those in unvaccinated TBE patients. In contrast to the unvaccinated controls, most of the VBTs displayed a delayed IgM antibody response and had high avidity and strongly neutralizing antibodies already in the first sample taken upon hospitalization. The antibody profile of these patients therefore had the characteristics of an anamnestic immune response. In the VBTs analyzed, immunological priming and memory were apparently not sufficient or fast enough to prevent the disease.  相似文献   
20.
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   
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