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101.
C. G. Bien C. E. Elger Y. Leitner M. Gomori B. Ran H. Urbach B. Wilken I. Korn-Lubetzki 《European journal of neurology》2007,14(4):387-390
Five young children developed slowly progressive hemiparesis as the initial manifestation of Rasmussen encephalitis (RE). Three have remained seizure free over an observational period of 1.3–1.9 years. In the remaining two patients, seizures occurred after 0.5 and 0.6 years respectively. We suggest that RE might be presently underdiagnosed and should be suspected in cases of new onset hemiparesis. In this series, three out of five patients showed oligoclonal bands on examination of cerebrospinal fluid (CSF) which represented additional diagnostic hints towards an immune-mediated condition. According to recently published formal diagnostic criteria, evidence of progressive cerebral hemiatrophy or bioptic identification of RE-typical inflammation confirms the diagnosis in such cases. Long-term immunotherapy is recommended in order to prevent further tissue loss and functional decline. 相似文献
102.
Hong Li Fassil Ketema Anne M Sill Kristen M Kreisel Farley R Cleghorn Niel T Constantine 《International journal of infectious diseases》2007,11(5):459-465
OBJECTIVES: We sought to modify the Serodia HIV-1/HIV-2 particle agglutination assay (PA), a simple and cost-effective HIV assay that is used globally for the detection of HIV antibodies, as a sensitive/less sensitive test (S/LS) to identify recently infected individuals and to estimate HIV incidence. METHODS: The Serodia PA test was modified as an S/LS test (PA-LS) by using HIV antigen-coated gelatin particles at a dilution of 1:68 and a specific diluent, and calibrated using 37 HIV clade B seroconversion panels (309 samples) from Trinidad and from a commercial source that were tested at dilution intervals from 1:10 to 1:80,000. The greatest sensitivity for correctly classifying samples from recent and established infections was determined by receiver operator curve (ROC) analysis. RESULTS: At a 1:40,000 sample dilution and a days post-seroconversion cutoff of 190 days, the PA-LS test yielded a 97% sensitivity for classifying recent and established infection samples. Furthermore, at a 1:20,000 dilution, the positive predictive value for correctly identifying recently infected individuals was 99%. The PA-LS test offers a 30-44-fold cost saving over currently available S/LS tests. CONCLUSION: A modified, low cost and simple-to-perform PA test is appropriate for use in resource-limited countries, and has exhibited excellence in distinguishing recent from established HIV infection. 相似文献
103.
Hong Wang Venkatraman Siddharthan Jeffery O. Hall John D. Morrey 《Journal of neurovirology》2009,15(4):293-299
Prior findings led us to hypothesize that West Nile virus (WNV) preferentially transports along motor axons instead of sensory
axons. WNV is known to undergo axonal transport in cell culture and in infected hamsters to infect motor neurons in the spinal
cord. To investigate this hypothesis, WNV was injected directly into the left sciatic nerve of hamsters. WNV envelope-staining
in these hamsters was only observed in motor neurons of the ipsilateral ventral horn of the spinal cord, but not in the dorsal
root ganglion (DRG). To evaluate the consequence of motor neuron infection by WNV, the authors inoculated wheat germ agglutinin—horseradish
peroxidase (WGA-HRP) 9 days after WNV sciatic nerve injection, and stained the spinal cord and the DRG for HRP activity 3
days later. The degree of HRP-staining in DRG was the same in WNV- and sham-infected animals, but the HRP-staining in the
motor neuron in the ventral horn was considerably less for WNV-infected hamsters. To investigate the mechanism of WNV transport,
hamsters were treated with colchicine, an inhibitor of membranous microtubule-mediated transport. The intensity of the WNV-stained
area in the spinal cord of colchicine-treated hamsters at 6 days after WNV infection were significantly reduced (P≤.05) compared to the placebo-treated hamsters. These data suggest that WNV is preferentially transported through the motor
axons, but not the sensory axons, to subsequently infect motor neurons and cause motor weakness and paralysis. 相似文献
104.
新型纳米根管充填材料对成骨细胞生长的影响 总被引:2,自引:0,他引:2
通过体外培养的成骨细胞,采用二甲基噻唑二苯基四唑溴盐比色法和流式细胞术对新型纳米根管充填材料(nHA-PA66)作用下的成骨细胞生长情况的变化进行研究,评价其对成骨细胞生长的影响。以该材料的细胞培养基浸提液作用于实验组细胞,对照组采用培养基本身。实验组和对照组成骨细胞的生长情况和细胞周期无显著性差异,表明该新型纳米材料对成骨细胞的生长和细胞周期无不良影响。提示新型纳米根管充填材料的成骨细胞相容性较好,具有用作根充材料的基础。 相似文献
105.
目的了解窒息新生儿在听觉刺激诱发脑神经活动时的脑氧合代谢和脑血流量的改变。
方法1998~2003年北京中日友好医院儿科选择窒息新生儿34例为窒息组,健康新生儿40名为对照组。使用近红外光谱仪,观察听觉刺激试验诱发的脑氧合血红蛋白\[Hb O2\]、还原血红蛋白\[Hb H\]和总血红蛋白\[Hb tot\]浓度的变化,并比较两组脑氧合代谢和脑血流量的改变。根据\[Hb O2\]、\[Hb H\]和\[Hb tot\]不同的变化,将氧合代谢曲线分为A(\[Hb O2\]、\[Hb H\]和\[Hb tot\]均增加); B(\[Hb O2\]和\[Hb tot\]增加,\[Hb H\]降低);C(\[Hb O2\]和\[Hb tot\]降低,\[Hb H\]增加)3种曲线类型。
结果窒息组中25例(25/34、73.5%)显示C型变化,对照组中28例(28/40、70.0%)显示A型变化,两组中A、C两型例数比较差异显著(P<0.05)。两组\[Hb O2\]和\[Hb tot\]数值变化幅度比较差异显著(P<0.05)。
结论窒息新生儿听觉刺激诱发相应皮层的神经活动时,显示局部脑血流量下降、氧合代谢降低,重度窒息儿更明显。 相似文献
106.
产程图上临产起始点一直缺乏精确性。临产开始的标志是有规律且逐渐增强的子宫收缩,同时伴随进行性宫颈管消失、宫口扩大和胎先露下降。从定义上看,它是一个过程,需要客观检查,还要结合产妇对其阵痛的主观感受。因此,多年来临床上对产程起始点的判断,没有一个确切的时点,往往根据检查结果追溯产妇的主观感觉,来绘制产程图。这种传统追溯法,影响了产程的准确性和对产程图信息的利用率。 相似文献
107.
Glucocorticoid effects on kainic acid-induced motor seizures and wet dog shakes in rats were investigated by adrenalectomy and dexamethasone treatment. One-day adrenalectomy attenuated kainic acid-induced wet dog shakes and seizure activity. These effects were restored by dexamethasone. Administration of dexamethasone to non-adrenalectomized rats potentiated kainic acid-induced wet dog shakes and severity of seizure activity. These results suggest that glucocorticoids may play an important role in modulating the severity of kainic acid-induced seizures and wet dog shakes. 相似文献
108.
109.
肝癌多药耐药产生与低糖环境的关系 总被引:5,自引:1,他引:4
目的探讨局部微环境低糖与肝细胞癌多药耐药性(MDR)产生的关系及影响机制。方法低糖培养HepG2细胞,应用流式细胞术Annexin V/PI法检测低糖培养的细胞在化疗药物5-氟脲嘧啶(5-Fu)作用后的凋亡情况,分别应用荧光定量聚合酶链反应(PCR)技术和Western blot技术检测低糖培养后HepG2细胞内多药耐药相关基因mdr1、MRP1、LRP的mRNA和蛋白水平的表达。结果在低糖环境下生长时间越长的HepG2细胞对5-Fu的抵抗越强,而且随着低糖培养时间的增加,5-Fu诱导的HepG2细胞的凋亡高峰延迟。低糖培养的HepG2细胞内多药耐药相关基因mdr1、MRP1、LRP在mRNA和蛋白水平的表达随低糖培养时间的延长而升高,以LRP的改变最为显著。结论肝癌生长微环境葡萄糖耐量不足也是肝癌产生MDR的原因之一。低糖可通过上调一组多药耐药相关基因的表达而诱导肝癌的多药耐药性。 相似文献
110.