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目的:神经断端保留小间隙的静脉桥接模拟神经外膜形成神经再生室,为周围神经再生创造了良好的生理环境,从而保证神经束的良好对合。实验采用部分脱乙酰甲壳质作为套管材料,用小间隙桥接方法修复坐骨神经损伤,观察套管内的神经再生情况,并与传统外膜缝合法进行比较。方法:实验于2001-01/2002-10在北京大学人民医院创伤骨科实验室完成。①主要材料:实验所用中空圆柱形套管为北京大学人民医院与中国纺织科学院共同发明的一种部分脱乙酰甲壳质生物套管(专利号:01136314.2)。实验中所用套管尺寸为:管长4 mm,壁厚0.1 mm,内径1.5 mm。②实验动物:健康成年雄性SD大鼠20只,随机分成2大组,每组10只,每一大组全部10只动物的左腿坐骨神经为一组,右腿坐骨神经为另一组,每组10根坐骨神经。另取5只同样大鼠双侧坐骨神经未做处理作为正常对照组。③实验方法:外膜原位缝合组:切断坐骨神经,显微镜下神经外膜原位缝合;生物套管小间隙原位桥接组:切断坐骨神经,显微镜下小间隙套管桥接;断端旋转180°外膜缝合组:切断坐骨神经,显微镜下远端旋转180°后,神经外膜缝合;断端旋转180°生物套管小间隙桥接组:切断坐骨神经,显微镜下远端旋转180°后,小间隙套管桥接。④实验评估:术后第7,14,21,28,42天取坐骨神经,进行免疫组织化学染色及观察。结果:再生神经延套管中央走行,7 d时已有部分纤维通过2 mm间隙,14 d时有髓纤维数量明显多于近端。21 d后,套管组与原位外膜组新生有髓神经纤维数相近。再生纤维胞核数量较多,髓鞘纤细。套管结构完整。结论:此种部分脱乙酰甲壳质生物套管内的再生神经连续、整齐,髓鞘完整,其神经再生情况好于传统外膜缝合法。  相似文献   
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Aim  To assess lower extremity bone mineral density (BMD) of children with congenital spinal dysfunction and examine factors that may influence BMD in this population. Method  Forty‐four children (25 females, 19 males) aged 6 to 18 years (mean 11y 11mo, SD 3y 6mo) with congenital spinal dysfunction (35 with myelomeningocele, seven with lipomas, one with sacral agenesis, one with caudal regression) were enrolled in the study. A health survey including ambulatory status, history of bladder augmentation, and history of fracture was administered. Each participant had a physical examination including Tanner stage and neurological level. Dual‐energy X‐ray absorptiometry scans of the lateral distal femur (LDF) and, when possible, lumbar spine were obtained. We reported LDF BMD results as z‐scores for three regions of interest (metaphyseal, metadiaphyseal, and diaphyseal). Univariable and multivariable analyses examined relationships between LDF BMD and the other variables. Results  BMD was significantly related to ambulatory status (14 non‐ambulatory, 15 partly ambulatory, 15 fully ambulatory) and neurological level (13 with low‐level lesions, 15 medium‐level, 16 high‐level) in the univariable analysis (p<0.01 for both in all three regions). Neither history of fracture, nor Tanner stage, nor history of bladder augmentation showed a significant relationship to BMD. The significance of ambulatory status and neurological level in the univariable analysis failed to persist in the multivariable analysis of this study with a small sample size. Interpretation  The LDF measurement proved to be a viable technique for assessing BMD in children with congenital spinal dysfunction. LDF BMD was sensitive to differences in three categories of ambulation. The overall influence of neurological level was not deemed as important as ambulation.  相似文献   
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Antiviral Chinese medicinal herbs against respiratory syncytial virus.   总被引:11,自引:0,他引:11  
Forty-four medicinal herbs were tested for antiviral activities against respiratory syncytial virus (RSV) by means of the cytopathologic effect (CPE) assay. Twenty-seven of the 44 medicinal herbs showed potent or moderate antiviral activities against RSV with 50% inhibition concentration (IC(50)) ranging from 6.3 to 52.1 microg/ml, and with selectivity index (SI) ranging from 2.0 to 32.1. Further purification of the active extracts from Sophora flavescens Ait. and Scutellaria baicalensis Georgi led to the identification of anagyrine (2), oxymatrine (7), sophoranol (10), wogonin (12), and oroxylin A (13) as the potent anti-RSV components.  相似文献   
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OBJECTIVES: To establish a registry for Chinese children with onset of type 1 (insulin dependent) diabetes mellitus before 15 years of age and to determine the incidence of childhood onset type 1 diabetes mellitus in Chinese children in Hong Kong. RESEARCH DESIGN AND METHODS: A registry was established in 1997 to collect childhood diabetes cases retrospectively from all districts in Hong Kong. The study included all newly diagnosed cases of diabetes with onset < 15 yr of age from 1st January 1984 to 31 December 1996. Primary ascertainment was based on review of medical records at all regional public hospitals in Hong Kong and survey of all the registered practitioners in Hong Kong. The secondary source of validation was made impractical, if not impossible, because of the recent implementation of the Personal Data Privacy Ordinance in Hong Kong. RESULTS: A total of 255 diabetic cases were identified, 227 type 1 diabetes mellitus (218 were Chinese), 18 type 2 diabetes mellitus and 11 secondary diabetes. 246 patients were Chinese and 9 non-Chinese. The age-standardized incidence of type 1 and type 2 diabetes mellitus in southern Chinese children in Hong Kong was 1.4/100,000/yr and 0.1/100,000/yr respectively for children < 15 yr of age during the study period. The incidence rates for type 1 diabetes were 0.9, 1.5 and 1.7 per 100,000/yr for 0-4 years, 5 to 9 years and 10 to 14 years age-groups respectively. The incidence for males was 1.2/100,000/yr and for females 1.7/100,000/yr. A significant increase in the incidence was demonstrated during the study period by simple linear regression (slope 0.14/100,000/year, r2 = 0.73, p = 0.0002) CONCLUSIONS: A diabetic registry is established in Hong Kong. This study documents a very low incidence rate of childhood type 1 diabetes mellitus in southern Chinese children in Hong Kong and we have seen an increasing incidence of the disease in the past 13 years.  相似文献   
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Reactive oxygen species play a role during brain injury due to closed head trauma. Enzymatic or nonenzymatic antioxidants may protect brain tissue against oxidative damage. The present study was performed to assess the changes of endogenous indices of oxidative stress in serum from rats subjected to head trauma and whether treatment with propofol and/or erythropoietin (EPO) modifies the levels of endogenous indices of oxidative stress. For these purposes, female Wistar Albino rats were divided into five groups: non-traumatic sham group, trauma performed control, trauma with propofol (i.p.), trauma with EPO (i.p.) and trauma with propofol and EPO performed study groups. At the end of the experimental procedure, blood was taken by cardiac puncture to determine superoxide dismutase (SOD) and xanthine oxidase (XO) activities as well as malondialdehyde (MDA) and nitric oxide (NO) levels in serum. Serum MDA level of control traumatic brain injury (TBI) group was significantly higher than sham operation group (p<0.012). Serum MDA levels in propofol, EPO and propofol+EPO groups were found to be decreased in comparison with control group (p<0.039, p<0.030 and p<0.018, respectively). Serum NO level was found to be increased in TBI group, but difference was not statistically significant when compared to sham-operated group (p=0.092). Propofol, EPO and propofol+EPO administration efficiently reduced serum NO levels to reach sham-operated group (p<0.002, p<0.001 and p<0.015, respectively). These results suggested that acute administration of both propofol and EPO altered the indices of oxidative stress similarly against brain injury due to trauma.  相似文献   
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Prolonged fever of unknown origin (FUO) is a challenging and important medical problem. Tuberculosis is the most frequent cause of FUO, especially in endemic regions, such as developing countries. We present a case of cervico-mediastinal tuberculous lymphadenitis that had been searched and followed up as a prolonged FUO. Especially in endemic areas, tuberculosis should be borne in mind in the differential diagnosis of FUO cases with granulomatous lymphadenitis presenting as prolonged or recurrent fever, even if the cultures and polymerase chain reaction for Mycobacterium tuberculosis are negative.  相似文献   
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BACKGROUND: The purpose of this prospective, randomized, blinded to observer study was to assess the analgesic effect and safety of intrathecal morphine (ITM) in post-operative pain control in children after heart surgery with a sternotomy incision. METHODS: Eighty children, 3-55 kg in body weight, undergoing elective cardiac surgery with opioid-based anaesthesia were randomly divided into two treatment groups to receive either 20 micrograms/kg ITM at induction of anaesthesia or control. To standardize the protocol for administration of post-operative rescue intravenous morphine boluses and infusion (20-60 micrograms/kg/h), the Cardiac Analgesic Assessment Scale (CAAS) was used. RESULTS: Nine patients were excluded from the study after randomization. Thirty-five patients were enrolled to the ITM group and 36 to the control group. The groups were similar for demographics and intra-operative clinical characteristics. The mean time for the first intravenous morphine dose from ITM administration or equivalent time zero in the control group was significantly longer (P = 0.003) in the ITM group compared with the control group (12.3 vs. 8.7 h). Time from Paediatric Intensive Care Unit (PICU) admission to the start of intravenous morphine was also significantly longer (P = 0.01) in the ITM group (6.0 vs. 3.4 h). The total intravenous morphine consumption over the mean 19 post-operative hours was significantly lower (P = 0.03) in the ITM group. However, the use of ITM did not result in earlier extubation or earlier discharge from the PICU. Of the 35 patients who received ITM at induction of anesthesia, 20% (n = 7) did not require any additional morphine in the PICU compared with three out of 36 control group patients. This did not reach statistical significance. The incidence of adverse events was low in both groups. CONCLUSIONS: An ITM dose of 20 micrograms/kg had a significant (P = 0.03) intravenous morphine-sparing effect after cardiac surgery. Effective analgesia was observed for 12 h after administration of intrathecal morphine.  相似文献   
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