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51.
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
52.
Christian J. Sauder Cheryl X. Zhang Malen A. Link W. Paul Duprex Kathryn M. Carbone Steven A. Rubin 《Vaccine》2009
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
53.
Su Jin Lee Young Keun On Eun Jeong Lee Joon Young Choi Byung-Tae Kim Kyung-Han Lee 《Journal of nuclear medicine》2008,49(8):1277-1282
Vascular 18F-FDG uptake marker represents inflammation in atherosclerotic lesions, but whether inflammation can be reversed by risk-modifying interventions has not, to our knowledge, been demonstrated. In this study, we evaluated the change of vascular 18F-FDG uptake in response to lifestyle intervention on serial PET/CT scans and further assessed how the findings relate to atherogenic risk reduction. METHODS: A total of 60 healthy adults underwent 18F-FDG PET/CT scans and atherogenic risk-factor assessment at baseline and again after 17.1 +/- 8.3 mo of practicing lifestyle modification. The PET/CT images were evaluated for the presence of vascular 18F-FDG lesions, and vessel-to-blood-pool 18F-FDG ratios were measured. Indices from summed ratios of positive lesions were compared and correlated to atherogenic risk factors. RESULTS: At follow-up, significant reductions in diastolic blood pressure (P < 0.05), total cholesterol (P < 0.05), and low-density lipoprotein level (P < 0.05) and an increase in high-density lipoprotein (HDL) level (P < 0.0001) were demonstrated. On the initial PET/CT scan, 50 of 60 subjects showed 1 or more 18F-FDG-positive lesions (5.9 +/- 5.0/subject), leading to a total of 352 vascular sites. On follow-up, 18F-FDG-positive lesions were significantly reduced to 2.1 +/- 2.2 sites per subject (P < 0.0001) and a total of 124 sites (64.8% reduction). Follow-up 18F-FDG-positive rates were significantly reduced for the aorta and iliac arteries. In addition, significant reductions in the whole-body 18F-FDG index from 1.39 +/- 1.23 to 0.53 +/- 0.59 (P < 0.0001) and carotid 18F-FDG index from 0.08 +/- 0.16 to 0.03 +/- 0.06 (P = 0.01) were shown. The whole-body 18F-FDG index correlated with total cholesterol (P < 0.05) and HDL level (P < 0.05), and the magnitude of reduction in the 18F-FDG index closely correlated to the amount of increase in plasma HDL level (P = 0.005). CONCLUSION: Our study demonstrated that vascular 18F-FDG uptake is reversed in response to atherogenic risk reduction by lifestyle intervention and that the magnitude of improvement correlates to increases in plasma HDL levels. Thus, serial 18F-FDG PET/CT may be useful for monitoring improvements in the inflammatory component of atherosclerotic lesions in response to risk modification. 相似文献
54.
A CT-free, intra-operative planning and navigation system for minimally invasive anterior spinal surgery - an accuracy study. 总被引:1,自引:0,他引:1
B Maier G Zheng C Ploss X Zhang K Welle L-P Nolte I Marzi 《Computer aided surgery》2007,12(4):233-241
OBJECTIVE: A comprehensive study was performed to evaluate the accuracy of a newly developed CT-free, intra-operative planning and navigation system for anterior spine surgery. MATERIALS AND METHODS: Instruments and an image intensifier were tracked using the SurgiGATE navigation system. A laboratory study was performed on 27 plastic vertebrae. Fiducial markers were implanted in the vertebrae for accuracy evaluation purposes, and a dynamic reference base was placed on the vertebrae to establish a patient coordinate system (P-COS). Two fluoroscopic images were used for intra-operative planning. The graft bed plan was recorded in P-COS, followed by surgical formation of the graft bed, which was visualized. To evaluate the accuracy, the vertebrae were scanned with CT, and the markers were used to calculate an accurate paired-point registered transformation between the CT coordinate system and P-COS. RESULTS: Using the new SPO module, accurate planning and navigation of a resection of the vertebral body is possible using two fluoroscopic images. The overall mean error between the planned resection volume and the actual resection was 0.98 mm. In addition, the module can serve as an educational tool for training spine surgeons. CONCLUSIONS: The new fluoroscopy-based system can be used safely for accurate performance of anterior resection during spondylodesis. New methods for safe and accurate registration during anterior spine surgery need to be developed. 相似文献
55.
临床技能培训与和谐医患关系构建是临床医学教育中两个不可分割的重要组成部分.促进临床技能培训与和谐医患关系的协调发展,达到完美和谐的统一,以提高医学研究生的培养质量.武汉大学人民医院采用具有特色的新型培养方式,加强研究生法律意识、医德教育,注重换位思考,提高专业技能,保持心理健康,改进医患沟通技巧,在研究生教育工作中取得了良好的效果. 相似文献
56.
α-平滑肌肌动蛋白和β-肌动蛋白在瘢痕组织中的表达 总被引:4,自引:0,他引:4
目的 探讨α-平滑肌肌动蛋白(α-SMA)和β-肌动蛋白(β-actin)对增生性瘢痕形成的可能作用。方法 采用荧光定量PCR法检测10例增生性瘢痕和10例正常皮肤组织中α-SMA和β-actin的表达水平。结果 增生性瘢痕组织中α-SMA和β-actin表达水平均高于正常皮肤组织,差异有统计学意义(P<0.01)。结论 α-SMA和β-actin在瘢痕增生中起重要作用;由于β-actin在瘢痕组织和正常皮肤中的不恒定性,建议在瘢痕的mRNA定量研究中不作为内参照物。 相似文献
57.
颈性眩晕的分型治疗及疗效分析 总被引:7,自引:0,他引:7
目的 将颈性眩晕分为上、下颈性眩晕,采取不同治疗方法并与常规治疗方法的疗效比较,以寻求更好的治疗方法。方法 将135例颈性眩晕随机分为试验组和对照组,对其治愈率及治疗时间进行统计学分析。结果 试验组的治愈率高于对照组,而试验组的治疗时间短于对照组,均有统计学意义。结论 对颈性眩晕进行分型并采用不同的治疗方法能提高治愈率,缩短治疗时间。 相似文献
58.
目的:了解TGF-β受体和整合素在瘢痕增生和挛缩过程中的作用.方法:通过荧光定量PCR法(FQ-PCR)测定经TGF-β受体、整合素和粘着斑激酶(FAK)抗体阻断后培养的瘢痕成纤维细胞TGF-β受体以及整合素表达量的变化.结果:经不同抗体阻断后培养的瘢痕成纤维细胞其TGF-β RI和整合素β 1的基因拷贝数均较阴性对照组有不同程度的下降(P<0.05).结论:TGF-β受体和整合素介导的信号传导途径间可能存在着正反馈的效应,共同促进瘢痕的增生和挛缩.FAK是两条信号传导途径的交汇点和作用的中心环节. 相似文献
59.
F X Pi-Sunyer 《Nutrition (Burbank, Los Angeles County, Calif.)》1991,7(4):292-294
There are several possible determinants of obesity, including impaired thermogenesis and the differential utilization of fuels in different tissues. Whereas hypometabolism may initiate obesity in some people, once obese, individuals tend to manifest a higher resting metabolic rate because of their greater fat-free mass, exhibit an impaired thermic response to food, and expend more calories than lean individuals for equivalent amounts of activity. As a result, over a 24-h period, obese people generally expend more energy than lean people. A second determinant of obesity is related to fuel utilization and suggests that those predisposed to be obese may have an innate insulin resistance in muscle, leading to decreased uptake, oxidation, and storage of glucose in this tissue. As a result, the glucose is shunted to adipose tissue, where it is stored. With regard to treatment of obesity, emphasis on increased energy expenditure through the inclusion of reasonable amounts of activity is essential. However, this must always be combined with restraint in caloric intake. 相似文献
60.