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61.
Although there are effective antibacterial agents against plague, newer antibacterial agents have been developed which show more potent activity against other bacterial organisms, but have not been tested againstYersinia pestis. A strain ofYersinia pestis was selected (no. 22; National Institute of Infectious Diseases, Tokyo, Japan) that caused a systemic infection in mice.Y. pestis no. 22 was intraperitoneally inoculated into DDY-strain mice, and 13 oral or 6 injectable antibacterial drugs given to the infected mice at varying doses 1 and 24 hours after infection. Levofloxacin, sparfloxacin and ofloxacin were the most effective oral agents against the infection, and prulifloxacin and pazufloxacin were also effective but to a lesser extent. Also, gentamicin and arbekacin were the most potent injectable antibacterial agents againstY. pestis. These results suggest that there are several new drugs, both oral and injectable, which exert excellent in vivo antibacterial activity against a mouse infection model and may be useful for the clinical treatment of plague.  相似文献   
62.
目的 探讨难治性支气管—肺部感染(难治组)衣原体、支原体两种病原体的表达。方法 应用ELISA法检测了29例难治性支气管—肺部感染两种非典型病原体急性感染指标,衣原体抗体IgM、支原体抗体IgM及冷凝集实验,并常规细菌学检查,与同期住院的普通性下呼吸道感染(普通组)40例,门诊及住院的急性上呼吸道感染(上感组)30例进行比较。结果 难治组衣原体急性感染率68.9%,显著高于普通组、上感组,上感组最低;支原体急性感染率难治组34、5%,显著高于普通组、上感组;衣原体混合支原体、衣原体混合其他致病菌感染均显著高于普通组和上感组。结论 难治性下呼吸道感染中衣原体、支原体感染率较高,且易与多种病原体混合感染,衣原体的慢性感染可能是难治感染的重要原因。  相似文献   
63.
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   
64.
This article describes the association between previous infection and/or vaccination and the development of optic neuritis (ON) in 18 children. Ten of these children subsequently developed clinically definite multiple sclerosis (MS), while in 8 patients a clinically definite etiology could not be confirmed. Vaccination preceded the first ON attack in 6 patients, all but one of whom subsequently developed MS. It also preceded subsequent demyelinating events in 6 patients. Ten of the patients had a bacterial or viral infection within the 2 weeks prior to the first symptoms of ON. Intrathecal antibody synthesis against 2 or more viruses could be shown in 5 out of 8 patients studied; 5 out of 6 patients had oligoclonal antibodies in CSF and 12 out of 16 patients a high IgG index. Neither intrathecal antibody synthesis against 2 or more viruses nor elevated IgG indexes could be found in the control patients. Measles and mumps occurred at a significantly later age in the children who subsequently developed MS than in the control children, and these patients had significantly more events that might have impaired the blood-brain barrier than the controls. These results indicate that immunological events leading to MS may be triggered during childhood. Vaccination and infection often precede ON in childhood. Intrathecal viral antibody production can occur already in childhood at the time of the first symptoms of MS.  相似文献   
65.
The presence of free immunoglobulin light chains (FLCs) in the cerebrospinal fluid (CSF) and sera of patients with human immunodeficiency virus-1 (HIV-1) infection, multiple sclerosis (MS), and neurologically healthy control individuals was investigated by paying special attention to ensure that only truly free light chains would be detected. The FLCs were extracted by specifically binding them to Sepharose-coupled anti-FLC monoclonal antibodies, and thereafter they were electrophoresed and immunoblotted with monoclonal antibodies to both light chain (LC) isotypes. A frequent occurrence of kappa and lambda FLCs was found in both CSF and sera of HIV-1 infected patients. In HIV-1 infection and in MS, the frequency of FLCs of the CSF was equal. In healthy controls, only occasional weak FLCs were observed in either CSF or serum. FLC bands of the CSF from patients with HIV-1 infection tended to be more intensive than those of the appropriately diluted sera. Both intrathecal synthesis of FLCs and their transudation from sera through the impaired blood-brain barrier (BBB) may contribute to this. Increasing severity of general HIV-1 infection was accompanied by an increase of FLC intensity in sera. A qualitative demonstration of FLC in the CSF may be meaningful only in the absence of altered BBB function.  相似文献   
66.
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   
67.
The Flinders Sensitive Line (FSL) of rats has been selectively bred to have increased sensitivity to cholinergic agonists. However, these rats exhibit altered responsiveness to a number of noncholinergic agents, such as apomorphine, buspirone and ethanol. This study compared the FSL and control Flinders Resistant Line (FRL) rats in terms of their hyperthermic response to the phencyclidine (PCP) receptor agonist, MK-801 (0.2 mg/kg SC) and their MK-801 binding characteristics. We have found that FSL rats react with a delayed hyperthermia, having a significantly lower hyperthermia for the first 120 min of observation. Thereafter the response does not differ in FSL and FRL rats. Both groups had similar affinities and numbers of [3H]MK-801 binding sites in the hippocampus/cerebral cortex. Pretreatment with scopolamine (1 mg/kg SC) failed to affect MK-801-induced hyperthermia in either line of rats. These findings suggest that selective breeding of FSL rats attenuated the secondary mechanisms involved in the PCP receptor-mediated hyperthermic response. However, by itself cholinergic supersensitivity does not appear to be a major factor in the blunted responsiveness of FSL rats to MK-801.  相似文献   
68.
脐动脉血PCT、CRP检测在早产儿早期感染中的作用   总被引:1,自引:0,他引:1  
目的:为进一步提高早产儿重症感染的早期诊断率探讨一种快速、可靠的方法。方法:用LUMITestPCT方法检测我院出生的有感染可能的早产儿的脐动脉血清降钙素原(PCT)。同时检测脐动脉血C反应蛋白(CRP);由新生儿专业的医师对其病情进行观察,在不知道PCT值时做出病情的临床诊断,52例病例分为:重症感染组(n=28)和对照组(n=24)。进行回顾性对比分析。结果:早期开始的早产儿感染与CRP、PCT浓度在出生时的增加相关,差异有极显著性(P<0.001);脐动脉血中,PCT浓度的增加与CRP水平变化呈正相关(r=0.88)。PCT的敏感性(96.4%)和特异性(95.8%)均高于CRP(敏感性75%,特异性91.6%)。结论:PCT可作为早产儿早期感染的早期、快速检测指标,与CRP相比,PCT敏感性、特异性均高。本研究方法对早产儿无创伤。  相似文献   
69.
目的:探讨肝硬化患者幽门螺杆菌( Hp)感染的临床特点.方法:对162例已行胃镜和幽门螺杆菌检查的肝硬化患者Hp感染情况进行回顾性分析.结果:Hp感染在性别和年龄间差异均无显著性(P>0.05);Hp感染率随食管静脉曲张加重、肝功能恶化、门脉高压性胃病加重而降低(P<0.05~P<0 .01);Hp感染在消化性溃疡的有无发生间差异无显著性(P>0.05).结论:在肝硬化患者中,Hp感染与食管静脉曲张、肝功能恶化、门脉高压性胃病、消化性溃疡的发生无关.对有Hp感染的肝硬化患者无需行根除治疗.  相似文献   
70.
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