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秦立篷  李丁  张菊  韩锋产  阎小君 《医学争鸣》2002,23(14):1295-1297
目的:克隆幽门螺杆菌ureB基因,并进行表达,验证表物的反应原性。方法:应用PCR技术从技术临床分离株中扩增出ureB基因,克隆入载体pGEM-7zf( )进行测序,进一步转到友大肠杆菌表达载体pBV220进行诱导表达,以Western blot实验验证重组蛋白的反应原性。结果:测序后经同源性比较,证实扩增后得到的片断确为ureB基因,并原核表达出可被抗Hp抗体识别的非融合重组蛋白。结论:获得了有反应原性的重组ureB蛋白。  相似文献   
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BACKGROUND: The MR and pathologic features of hippocampal sclerosis (HS) are well described and include volume decrease and T2-weighted signal increase for MRI, and neuron cell loss and gliosis for pathology. OBJECTIVE: To confirm the established correlation between hippocampal volumes and neuron cell counts, and to study the still controversial association between signal change and gliosis. METHODS: The authors studied 44 patients (22 men and 22 women; mean age at surgery, 37 years) with refractory temporal lobe epilepsy. Quantitative assessment of hippocampal volumes and T2 relaxometry, and neuron and glial cell count in the region CA1 and molecular layer of the dentate gyrus was performed. The proportion of glial fibrillary acidic protein (GFAP)-positive glial cells (reactive astrocytes) was indicated. RESULTS: In a stepwise regression, the ipsilateral hippocampal volume was predicted best by the neuron cell count in the dentate gyrus (p = 0.005, r = 0.4). Hippocampal T2 time, however, was predicted best by the glial cell count in the dentate gyrus (p = 0.01, r = 0.4). None of the other cell counts contributed to either model. In the dentate, 31% of the glial cells were reactive astrocytes, whereas in CA1, 5% were reactive. CONCLUSION: The results confirmed the correlation between hippocampal volumes and neuron cell counts. T2-weighted signal increase in the hippocampus was mainly influenced by gliosis in the dentate gyrus, where a high proportion of glial cells show abnormal activity. This activity may reflect changes important in the development of hippocampal epileptogenicity.  相似文献   
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BACKGROUND: Filamentary keratitis is most often a chronic corneal condition, characterized by filaments attached at one or both ends to the cornea. Patients often experience foreign body sensation, grittiness, discomfort, photophobia, blepharospasm, and increased blinking. Filamentary keratitis is commonly the result of aqueous deficient dry eye syndrome. Management options include lubrication, punctal occlusion, removal of filaments, hypertonic saline, mucolytic agents, anti-inflammatory agents, and therapeutic contact lenses. CASE REPORT: A 58-year-old man came to us with acute symptoms of pain, photophobia, and redness x 2 days 0.S. The diagnosis of filamentary keratitis was made based on the clinical findings of positively staining mucus strands attached to the superior cornea. The patient was also found to have dry eye, blepharitis, and floppy eyelid syndrome. Numerous treatment regimens were implemented, including lubrication with non-preserved artificial tears, lubricating ointment, and topical steroids. The patient's condition was finally best managed with silicone plug punctal occlusion and therapeutic contact lenses. CONCLUSION: Filamentary keratitis can be a recurrent and incapacitating condition that may prove difficult to manage.  相似文献   
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Background and objective  The purpose of this study is to assess whether Chinese children with high apnea–hypopnea index (AHI) are sleepier by a modified Epworth Sleepiness Scale (ESS). Materials and methods  Records were retrospectively reviewed. We included children who were between 3 and 12 years old, admitted for overnight polysomnogram because of suspected obstructive sleep apnea syndrome (OSAS). A modified ESS was used to assess excessive daytime sleepiness (EDS) of the children. Results  One hundred ninety-two Chinese children were included. Children with high AHI, defined as AHI > 5.0, were sleepier than children with AHI less than or equal to 5. After adjustment by age, gender, and obesity, children with high AHI remained significantly sleepier. Modified ESS was significantly correlated with AHI (rho = 0.124, 95% CI = 0.004–0.281). Modified ESS score of >8 was the best cutoff point with the sensitivity and specificity of 0.29 and 0.91, respectively. The odds ratio of children with modified ESS > 10 having high AHI was 4.231 (95%CI = 1.248 to 14.338) and children with modified ESS > 8 had the highest odds ratio, 4.295(95%CI = 1.66 to 11.1), of having high AHI. Conclusion   Chinese children with high AHI appear to be sleepier than children with low AHI. Children with suspected OSAS and high modified ESS, i.e., ESS > 8, had significantly higher odds ratio of having high AHI. Increased sleepiness is a specific but not a sensitive symptom in snoring children with high AHI. Screening for EDS in snoring children may help us identify those with high AHI and prioritize the management of those children. All authors worked and the study was carried out in Kwong Wah Hospital in Hong Kong. There was no conflict of interest and no specific source of funding for the study.  相似文献   
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The first‐order kernel analysis in multifocal electroretinogram (mfERG) using low contrast stimulation is suggested as a way to detect the inner retinal responses in animal studies. In this case report, this protocol is applied to human patients with glaucoma to demonstrate the possibility of using mfERG as a tool to detect glaucomatous damage. Two patients with glaucoma were recruited and had mfERG measurements with the 103‐scaled hexagonal stimulus pattern at low (50 per cent) contrast. Their responses were analysed and compared with those from normal subjects with the mfERG measured under the same condition. In the normal subjects, there were obvious oscillatory components on the ascending and descending limbs of the first‐order kernel response to 50 per cent contrast. In the glaucomatous patients, the oscillatory component on the descending limb was obviously diminished. In addition, this component was significantly diminished in the quadrant with a glaucomatous visual field defect. This suggests that the low‐contrast stimulation condition in mERG measurement may provide a good way to detect glaucomatous damage and this may help in clinical diagnosis of glaucoma.  相似文献   
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