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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   
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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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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   
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普外科住院患者营养状况评价   总被引:21,自引:0,他引:21  
目的 调查本院 2 0 0 2~ 2 0 0 3年间普外科住院患者的营养状况。方法 采用多项营养评价指标测定 4 0 12例非急诊住院患者营养状况 ,分析年龄、疾病等因素与营养状况之间关系。结果 各项指标进行营养评价得出本院普外科非急诊患者营养不良的发生率分别是 :BMI 2 1 3% ,TSF5 0 6 % ,MAC 2 0 5 % ,AMC 2 1 2 % ,SGA 38 0 % ,MNA 2 0 8% ,ALB 2 4 2 % ,PA 35 4 % ,TLC 5 5 8%。 >6 0岁组老年患者、消化道疾病患者及恶性肿瘤患者营养不良发生率分别高于≤ 6 0岁患者、消化道外疾病患者及良性疾病患者 ,差异有显著性 (P <0 0 5 )。结论 本院普外科住院患者的营养不良发生率为 2 0 5 %~ 5 5 8% ,不同的营养评价指标得出的营养不良发生率不同。  相似文献   
47.
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   
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复杂LC术中胆管损伤的预防:附272例报告   总被引:3,自引:0,他引:3  
随着腹腔镜胆囊切除术(LC)的广泛开展及技术水平的日益提高,LC已被认为是胆囊切除的金标准。手术适应证逐渐扩宽,这也对手术者提出了更高的要求。内江市第六人民医院在1997年3月至2006年3月9年间共行LC手术1378例,其中复杂LC 272例,结合临床经验及教训就有关问题进行分析讨论。[第一段]  相似文献   
50.
Sixteen patients underwent surgical treatment for severe renovascular hypertension with rapidly progressive renal failure. These patients were assessed preoperatively with the measurement of serum creatinine and blood-urea levels (means 271 +/- 204 mumol/l and 15.6 +/- 10.3 mmol/l respectively), and renal clearances. 5 patients underwent aorto-renal bypass (bilateral in one case) and 11 patients were treated by autotransplantation of the kidney. Operative mortality was 6.2%. Early results were assessed at 1 and 6 months postoperatively. Renal function was normal in 8 patients, improved in 5 (p less than 0.05), unchanged in 1 and worse in 1 by aorto-renal bypass thrombosis. At long-term with a minimum follow-up of 12 months (mean 31 +/- 12 months), the initial improvement in renal function remained steady in 12 patients whilst 1 patient has gone on to hemodialysis. At middle and long-term, 81% of the patients were normotensive without medication or had improved blood pressure (p less than 0.001). These good results confirm the reversibility of renal ischemic lesions and support an aggressive attitude towards the use of revascularization in the surgical treatment of such patients with renovascular hypertension and renal failure.  相似文献   
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