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101.
Myoclonus dystonia syndrome(MDS)is an inherited movement disorder,and most MDS-related mutations have so far been found in theε-sarcoglycan(SGCE)coding gene.By generating SGCE-knockout(KO)and human 237 C>T mutation knock-in(KI)mice,we showed here that both KO and KI mice exerted typical movement defects similar to those of MDS patients.SGCE promoted filopodia development in vitro and inhibited excitatory synapse formation both in vivo and in vitro.Loss of function of SGCE leading to excessive excitatory synapses that may ultimately contribute to MDS pathology.Indeed,using a zebrafish MDS model,we found that among 1700 screened chemical compounds,Vigabatrin was the most potent in readily reversing MDS symptoms of mouse disease models.Our study strengthens the notion that mutations of SGCE lead to MDS and most likely,SGCE functions to brake synaptogenesis in the CNS.  相似文献   
102.
摘要目的本研究的摘要目的是开发一种非对比MRI方法来评估以足部的血管灌注区域为基础的糖尿病足的骨骼肌肉灌注情况。方法对5例健康志愿者和5例无外周动脉疾  相似文献   
103.
We assessed the relation between different fasting plasma glucose (FPG) levels of 5.6 to 6.9 mmol/L and the prevalence and severity of angiographic coronary artery disease (CAD) in high-risk Chinese patients. Among 512 subjects who were to undergo coronary angiography for the confirmation of suspected myocardial ischemia, 409 subjects were enrolled and categorized into 3 groups based on FPG levels: (1) 相似文献   
104.
We report that silver ion (Ag+) uptake is enhanced by 4-aminopyridine (4-AP), a well known voltage-sensitive potassium ion channel (Kv) blocker. Both bacterial (Escherichia coli) and mammalian (3T3 fibroblast) cells were used as model systems. Ag+ uptake was monitored with a scanning electrochemical microscope with an amperometric Ag+ ion-selective electrode (Ag+-ISE) and the respiration rates of E. coli cells were measured by oxygen reduction at an ultramicroelectrode. The results showed that not only the amount but also the rate of silver uptake by the cells increased significantly when 4-AP was added to the solution. For fibroblasts, the Ag+ uptake rate was 4.8 × 107 ions per cell per sec without 4-AP compared with 1.0 × 108 ions per cell per sec with 0.2 mM 4-AP. For E. coli cells, the uptake rate was 1.5 × 104 ions per cell per sec without 4-AP vs. 3.5 × 104 ions per cell per sec with 0.5 mM 4-AP and 5.9 × 104 ions per cell per sec with 1 mM 4-AP. Thus, 4-AP might be useful where silver is used as antimicrobial agent to speed its uptake.  相似文献   
105.
肌萎缩侧索硬化患者膈肌运动诱发电位   总被引:2,自引:1,他引:2  
Zhuang L  Tang X  Fan D  Xu X  Li B  Du H  Jiang J 《中华内科杂志》2002,41(4):241-243
目的 初步探讨膈股运动诱发电位(DMEP)在肌萎缩侧索硬化(ALS)患者的应用及特点。方法 以表面电极在肋间隙处记录37例ALS患者及31例正常对照者经颅及经项磁刺激时产生的膈肌复合肌肉动作电位潜伏期和波幅,并计算中枢运动传导时间(CMCT)。22例ALS患者同时接受了用力肺活量百分比(%FVC)测定。结果 ALS患者较对照者颈及皮层潜伏期延长,颈及皮层波幅对数降低,CMCT延长,皮层潜伏期、皮层波幅对数、CMCT均与锥体束受累相关;皮层潜伏期和CMCT与临床呼吸困难相关,颈潜伏期与%FVC相关。结论 CMCT、颈及皮层潜伏期是DMEP参数中反映ALS患者呼吸功能障碍的敏感指标。CMCT反映ALS患者与呼吸功能相关的皮质脊髓束功能,CMCT与颈潜伏期结合有助于全面准确地揭示ALS患者呼吸受累的本质。  相似文献   
106.
Purpose: To evaluate the performance of a prehospital trauma diversion system in Hong Kong, China. Methods: A retrospective analysis of prospectively collected data in the trauma registry of Queen Mary Hospital, Hong Kong from 1 January 2009 to 31 December 2013 was done. All adult patients aged 18 years or above, either primarily or secondarily diverted to Queen Mary Hospital according to the trauma patient diversion protocol, were recruited. Need for trauma center level of care was based on a consensus-based criterion standard published in 2014. Performance of the protocol in terms of overdiversion and under-diversion was determined. Results: A total of 209 patients were included for analysis. About 30% of the patients required trauma center level of care. The most common reason was the need for vascular, neurologic, abdominal, thoracic, pelvic, spine or limb-conserving surgery within 24 h of presentation. The over-diversion rate and underdiversion rate were 69.6% and 19.7% respectively. Conclusion: The trauma patient diversion protocol currently in use in Hong Kong is not accurate enough. Further revision and refinement is needed.  相似文献   
107.
108.
AIM:To testify the immunogenicity of a conservative B-cell linear epitope of Helicobacter pylori (H pylori) flagellin A. METHODS: Different programs were used to analyze the secondary structure, molecular hydropathy, and surface accessibility of H pylori flagellin A. Linear B-cell epitopes were estimated based on the structural and physiochemical information. Analysis of residue divergence was proposed to screen a conservative linear epitope. The 29-peptide (Pep29mer) synthesized by chemical method, including the predicted conservative B-cell epitope and a known K2d compatible T-cell epitope, was used to immunize mice, and then H pylori-specific antibodies were detected by ELISA. RESULTS: Based on the analyses of divergent amino acid residues, structural and physiochemical characteristics, it was strongly suggested that the short fragment NDSDGR was the core of a conservative linear epitope in flagellin A. Animals immunized by Pep29mer acquired efficient immune response. In detail, serum H pylori-specific IgA and IgGl increased significantly in immunized group, while IgG2a only had an insignificant change. H pylori-specific IgA in gastrointestinal flushing fluid also increased significantly. CONCLUSION: The conservative short fragment NDSDGR is the core of a linear B-cell epitope of flagellin A.  相似文献   
109.
OBJECTIVE: This study was designed to evaluate the effects of rosiglitazone (ROS) on insulin sensitivity, beta-cell function, and glycaemic response to glucose challenge and meal in subjects with impaired glucose tolerance (IGT). METHODS: Thirty patients with IGT (ages between 30 and 75 years and BMI (body mass index) < or = 27 kg/m2) were randomly assigned to receive either placebo (n = 15) or ROS (4 mg/day) (n = 15). All participants underwent a 75-g oral glucose tolerance test (OGTT), meal test, and frequently sampled intravenous glucose tolerance test (FSIGT) before and after the 12-week treatment. RESULTS: After 12 weeks of ROS treatment, there were significant increases in total cholesterol (TC) (4.25 +/- 0.22 vs 4.80 +/- 0.17 mmol/l, P < 0.001), high-density lipoprotein cholesterol (HDL-C) (1.25 +/- 0.07 vs 1.43 +/- 0.06 mmol/l, P < 0.05), and low-density lipoprotein cholesterol (LDL-C) (2.70 +/- 0.15 vs 3.37 +/- 0.17 mmol/l, P < 0.05) without changes in triglyceride concentration, TC/HDL-C and LDL-C/HDL-C ratio. Although the acute insulin response (AIR) to intravenous glucose and disposition index (measured as the ability of pancreatic beta-cell compensation in the presence of insulin resistance) remained unchanged, the insulin sensitivity (SI) and glucose effectiveness (SG) were remarkably elevated (0.38 +/- 0.06 vs 0.54 +/- 0.09 x 10(-5) min(-1)/pmol, P < 0.05; 0.017 +/- 0.002 vs 0.021 +/- 0.001 min(-1), P < 0.05, respectively) in the ROS group. The glucose, insulin, and c-peptide areas under curve (AUC) in response to OGTT and the glucose and insulin AUC during meal were significantly ameliorated in the ROS group. Five out of 15 (33%) and two out of 15 (13%) subjects treated with ROS and placebo, respectively, reversed to normal response during OGTT (P < 0.05). CONCLUSION: Rosiglitazone treatment significantly improved insulin resistance and reduced postchallenge glucose and insulin concentrations in patients with impaired glucose tolerance without remarkable effects on beta-cell secretory function.  相似文献   
110.
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