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101.
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
102.
103.
体外短波热疗联合前列腺灸及哈乐治疗非细菌性前列腺炎和前列腺痛疗效观察 总被引:5,自引:1,他引:4
目的 探讨慢性非细菌性前列腺炎(CNP)和前列腺痛(PD)的治疗方法。方法 应用体外短波热疗联合前列腺灸及α1A-肾上腺素能受体阻滞剂哈乐治疗CNP和PD患者26例,疗程8周。观察治疗前后前列腺炎症状评分(CPSI)与最大尿流率(MFR)变化。结果 有效率为80.8%。治疗前后CPSI和MFR均有显著改善(P〈0.05)。结论 体外短波热疗联合前列腺灸及哈乐治疗CNP和PD安全有效。 相似文献
104.
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
105.
利用圆形分布的统计方法分析急性脑梗死患者死亡时间昼夜节律特点 总被引:3,自引:0,他引:3
目的 回顾性分析64例急性脑梗死患者的死亡时间,探讨脑梗死患者死亡时间的昼夜节律变化的特点和规律,方法 分析64例死亡病例的临床资料,重点分析死亡时间,利用圆形分布的统计方法,计算出死亡高峰时刻和1天24小时内95%的死亡时间集中时段。结果 急性脑梗死患者的死亡高峰时刻为05:59:31,1天24小时内95%的死亡时间发生在01:04:23-10:54:39.结论 急性脑梗死患者的死亡时间有一定的昼夜节律分布的特点,清晨通常为死亡的高峰时段,与机体血栓性病理状态恶化或血压的昼夜波动有关,工作中应注意加强夜间和凌晨患者的管理和监测,必要时改变投药时间,最大限度地减少死亡率。 相似文献
106.
107.
目的研究肾草酸钙结石形成对肾组织bikunin基因和间α胰蛋白酶抑制物(IαI)蛋白表达的影响,探讨bikunin在尿结石形成中的意义。方法诱导实验性大鼠肾草酸钙结石模型,收集结石大鼠、正常大鼠、临床肾结石和非结石患者每组各8例的肾组织标本。采用免疫组化、逆转录聚合酶链反应(RT-PCR)和计算机图像分析技术分别检测所有大鼠和人肾组织中bikuninmRNA和IαI蛋白的表达水平。结果正常大鼠和非结石患者肾组织均存在bikuninmRNA和IαI蛋白的表达。肾草酸钙结石形成后,结石大鼠肾组织IαI蛋白的灰度值和bikuninmRNA的相对表达水平分别为198.43±15.17、0.70±0.14;肾结石患者肾组织IαI蛋白的灰度值和bikuninmRNA的相对表达水平分别为263.25±17.41、1.27±0.13,分别和对照组相比,均显著增加(P<0.05)。结论Bikunin作为构成IαI的轻链结构,在肾草酸钙结石形成后,bikuninmRNA的表达迅速增强,提示机体通过肾脏合成更多的bikunin来抑制肾草酸钙结石的形成。 相似文献
108.
目的介绍个体成长模型方法对大学新生适应能力中交往主动性的3次测查数据采用普通回归模型和个体成长模型进行分析。结果个体成长模型的拟合度比普通回归模型的拟合度要好,个体成长模型可在个体水平上分析个体随时间产生的变化。结论个体成长模型具有许多优点,熟悉这种重要的分析方法对纵向数据研究者是非常有益处的。 相似文献
109.
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
110.