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71.
72.
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   
73.
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   
74.
应用VTK技术建立唇腭裂可视化模型   总被引:3,自引:1,他引:2  
目的:寻求一种高效率、高精度建立唇腭裂患者颌面部可视化模型的方法.方法:利用薄层CT获取原始数据,运用k-均值聚类算法进行图像分割,结合VTK(Visualization Toolkit)技术进行可视化模型的建立.结果:建立了更为精确的唇腭裂患者颌面部的可视化模型,总结出了一种更为方便高效的通用可视化建模方法.结论:应用VTK方法建立可视化模型,软件开发周期更短,精度更高,应用更广泛.  相似文献   
75.
Background: Malposition of percutaneously inserted chest tubes is considered as a rare complication in critically ill patients. Its incidence, however, remains uncertain. The aims of the study were to assess the true incidence of chest tube malposition in critically ill patients and to identify predicting factors.

Methods: The authors prospectively studied 122 chest tubes percutaneously inserted in 75 consecutive critically ill patients. For clinical reasons independent of the study, thoracic computed tomography scanning was performed in 63 patients, allowing direct visualization of 106 chest tubes. Based on these findings, chest tube position was classified as intrapleural, intrafissural, or intraparenchymal. Factors predicting chest tube malposition were analyzed by univariate and multivariate analysis.

Results: The mean delay between chest tube placement and thoracic scan was 3.5 +/- 2.9 days. Twenty-two chest tubes were diagnosed as being intrafissural (21%), and 10 were diagnosed as being intraparenchymal (9%). The only predicting factor associated with the risk of malposition was the use of a trocar for the percutaneous insertion of the chest tube (P = 0.032).  相似文献   

76.
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   
77.
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   
78.
79.
泰素蒂加顺铂治疗进展期NSCLC的临床研究   总被引:5,自引:0,他引:5  
目的观察泰素蒂加顺铂方案治疗进展期非小细胞肺癌的临床疗效、毒副作用。方法收集可评价疗效的进展期非小细胞肺癌50例,以泰素蒂加顺铂方案进行化疗,泰素蒂75 mg/m2静脉滴注,第1天;顺铂25 mg/m2~30 mg/m2静脉滴注,第2天~第5天,每3周为一个周期,2~3周期后评价疗效和毒副反应并随访。结果50例患者中,总有效率为50.0 %,其中初治病例为53.1 %,复治病例为44.4 %,初复治病例间差异无显著性(P >0.05)。中位缓解期为5个月。中位生存期为9.5个月,1年生存率为61.0 %。毒副反应主要为骨髓抑制,白细胞下降达Ⅲ度、Ⅳ度者52.0 %,血小板下降达Ⅲ度、Ⅳ度者为14.0 %。血红蛋白下降不严重。其他毒副反应还有脱发、过敏反应、水钠潴留、静脉炎、末梢神经炎、口腔炎、腹泻等,但发生率均较低。结论泰素蒂加顺铂方案治疗进展期非小细胞肺癌,特别是复发病例,临床疗效比较满意,毒副反应能够耐受。辅以G蛳CSF可防治重度的骨髓抑制,有较好的临床应用价值。  相似文献   
80.
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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