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101.
The effects of radiofrequency electromagnetic field (RF-EMF) exposure on neuronal phenotype maturation have been studied in two different in vitro models: murine SN56 cholinergic cell line and rat primary cortical neurons. The samples were exposed at a dose of 1 W/kg at 900 MHz GSM modulated. The phenotype analysis was carried out at 48 and 72 h (24 and 48 h of SN56 cell line differentiation) or at 24, 72, 120 h (2, 4 and 6 days in vitro for cortical neurons) of exposure, on live and immunolabeled neurons, and included the morphological study of neurite emission, outgrowth and branching. Moreover, cortical neurons were studied to detect alterations in the expression pattern of cytoskeleton regulating factors, e.g. β-thymosin, and of early genes, e.g. c-Fos and c-Jun through real-time PCR on mRNA extracted after 24 h exposure to EMF. We found that RF-EMF exposure reduced the number of neurites generated by both cell systems, and this alteration correlates to increased expression of β-thymosin mRNA.  相似文献   
102.
Abstract  Impaired gastric slow waves, frequent gastrointestinal (GI) symptoms and altered GI peptides have been reported in Scleroderma (SSc) patients. The aim of this study was to investigate the associations among these three important components in GI dysmotility. Seventeen fasted SSc patients underwent four channel surface electrogastrography, measuring % of normal gastric slow waves or dysrhythmia. Patients completed a questionnaire designed by us to assess demographics, upper and lower GI symptoms (symptom presence, frequency and impact on quality of life, QOL), by YES/NO, Likert Scales and Visual Analogue Scales 1–100 mm (called GI Dysmotility Questionnaire, GIDQ) and health-related QOL by SF-36. Fasting plasma vasoactive intestinal peptide (VIP) and motilin levels were measured by peptide immunoassays. There were significant correlations between percentages of gastric dysrhythmias (bradygastria or arrhythmia) and a number of major GI symptoms such as nausea, abdominal bloating and pain. The plasma level of VIP was correlated positively with % dysrhythmia but negatively with % normal slow waves. Motilin was positively correlated with slow wave coupling (coordination). No major differences were noted in the measured peptides or gastric slow waves between limited SSc and diffuse SSc. Correlations were noted between SF-36 domain scores and our GIDQ scores. In SSc patients, gastric dysrhythmias are correlated with certain GI symptoms. Correlations are also noted between plasma VIP/Motilin levels and gastric slow waves. Thus in SSc, gastric dysrhythmias may be predictive of development of certain dyspeptic symptoms. Plasma VIP may be involved in the development of dysrhythmias.  相似文献   
103.
Mode conversion occurs when the ultrasonic guided waves encounter fractures. The aim of this study was to investigate the feasibility of fracture assessment in long cortical bone using guided-mode conversion. Mode conversion behavior between the fundamental modes S0 and A0 was analyzed. The expressions proposed for modal velocity were used to identify the original and converted modes. Simulations and phantom experiments were performed using 1.0-mm-thick steel plates with a notch width of 0.5 mm and notch depths of 0.2, 0.4, 0.6 and 0.8 mm. Furthermore, in vitro experiments were carried out on nine ovine tibias with 1.0-mm-wide partial transverse gap break and cortical thickness varying from 2.10 to 3.88 mm. The study confirmed that mode conversion gradually becomes observable as fracture depth increases. Energy percentages of the converted modes correlated strongly with fracture depth, as illustrated by the frequency-sweeping experiments on steel phantoms (100–1100 kHz, r2 = 0.97, p < 0.0069) and the fixed-frequency experiments on nine ovine tibias (250 kHz, r2 = 0.97, p < 0.0056). The approaches described, including mode excitation, velocity expressions and energy percentage criteria, may also contribute to ultrasonic monitoring of long bone fracture healing.  相似文献   
104.
Cationic lipid/DNA complexes (lipoplexes) represent a powerful tool for cell transfection; however, their use is still limited by important concerns, including toxicity and poor internalization into deep tissues. In this work, we investigated the use of shock wave-induced acoustic cavitation in vitro for the transfection of lipoplexes in human embryo kidney 293 cells. We selected shock waves with the ability to internalize 10-kDa fluorescein isothiocyanate-dextran into cells while maintaining survival rates above 50%. Cell transfection was tested using the green fluorescent protein-encoding plasmid pCX::GFPGPI2. Confocal microscopy and fluorescence-assisted cell sorting analyses revealed successful transfection after treatments ranging from 1 to 3 min using 60 to 180 shock waves at peak amplitudes of 12.3 ± 1.5 MPa. Interestingly, the combination of shock waves and lipoplexes induced a 3.1- and 3.8-fold increase in the expression of the reporter gene compared with the use of lipoplexes or shock waves alone, respectively. These results indicate that cationic DNA assembly and shock waves act in a synergistic manner to promote transfection of human cells, revealing a potential approach for non-invasive site-specific gene therapy.  相似文献   
105.
目的观察液电式体外冲击波治疗偏瘫肩痛(HSP)的疗效。方法脑卒中患者70例随机分为对照组(n=35)和观察组(n=35),两组患者进行运动疗法治疗,观察组同时对HSP肩关节进行体外液电式冲击波治疗。结果治疗4周后,观察组的治愈率为60.0%(21/35),总有效率为91.4%(33/35),对照组的治愈率为34.3%(12/35),总有效率为71.4%(25/35),两组比较差异有统计学意义(P0.05)。两组治疗后与治疗前比较疼痛视觉模拟(VAS)评分及上肢运动功能(Fugl-Meyer)评分均有显著改善,分别为(5.91±1.70)分vs(3.49±1.99)分、(5.80±1.47)分vs(4.69±1.67)分vs(24.86±9.08)分vs(46.47±9.91)分、(26.91±9.70)分vs(31.09±10.07)分,且观察组明显优于对照组(均P0.01)。结论液电式体外冲击波是一种可供选择的治疗HSP的较好方法。  相似文献   
106.
目的 评价特殊军事作业人工环境影响因素特征及其对人员健康的影响,为进一步开展控制措施的研究提供依据.方法 采用电磁辐射场强仪、声级计、温湿度计、风速仪、一氧化碳检测仪和二氧化碳分析仪,分别对某部军事作业密闭环境的微波辐射、噪声、温度、湿度、风速、一氧化碳和二氧化碳进行监测分析;采用自觉症状问卷,调查评价作业人员健康...  相似文献   
107.
目的:探讨2000 μW/cm2 电磁辐射对大鼠海马N-甲基-D-门冬氨酸受体亚单位2A(NR2A)蛋白及其mRNA水平表达的影响,揭示电磁辐射对大鼠学习记忆功能的损伤机制.方法:实验分为空白对照组,假辐射组,1 h/d、2 h/d、3 h/d辐射组.将辐射组大鼠固定体位,头部接受功率密度为2000 μW/cm2 的近场辐射,连续辐射30 d.通过Morris水迷宫检测大鼠的空间学习记忆能力,采用免疫组化法和Westernblot法检测大鼠海马组织NR2A蛋白表达的变化,RT-PCR法检测大鼠海马组织NR2A mRNA表达的变化.结果:假辐射组大鼠各项指标与空白对照组相比均无统计学差异(P>0.05);而各辐射组大鼠寻找安全平台的逃避潜伏期较空白对照组明显延长(P<0.05);各辐射组大鼠海马神经元排列紊乱,NR2A阳性细胞比率显著下降,海马组织NR2A蛋白及其mRNA表达水平明显降低(P<0.05).结论:2000 μW/cm2 电磁辐射可导致大鼠学习记忆功能下降,其机制可能与大鼠海马组织NR2A蛋白及其mRNA的表达降低有关.  相似文献   
108.
目的 了解自发Ⅰ型Brugada波患者的QT间期及QT间期离散度变化的意义.方法 对15例自发Ⅰ型Brugada波患者进行12导联心电图检测,描记12导联同步心电图,测量QT间期,QT离散度,比较呈典型Ⅰ型Brugada波与无Brugada波之间的差异及对照组之间的差异.结果 患者自发Ⅰ型Brugada波时,QT间期...  相似文献   
109.
Objectives: This study evaluated the impact of a chronic total occlusion (CTO) in a non‐infarct related coronary artery (IRA) on markers of reperfusion, infarct size, and long‐term cardiac mortality in patients with ST‐elevation myocardial infarction (STEMI). Background: A concurrent CTO in STEMI patients has been associated with impaired left ventricular function and outcome. However, the impact on markers of reperfusion is unknown. Methods: All 1,071 STEMI patients included in the TAPAS‐trial between January 2005 and December 2006 were used for this substudy. Endpoints were the association between a CTO in a non‐IRA and myocardial blush grade (MBG) of the IRA, ST‐segment elevation resolution (STR), enzymatic infarct size, and clinical outcome. Results: A total of 90 patients (8.4%) had a CTO. MBG 0 or 1 occurred more often in the CTO group (34.2% versus 20.6% (Odds Ratio [OR] 2.00, 95% confidence interval [CI]: 1.22–3.23, P = 0.006)). Incomplete STR occurred more often in the CTO group, (63.6% versus 48.2% [OR 1.96, 95% CI: 1.22–3.13, P = 0.005]). Median level of maximal myocardial‐band of creatinin kinase (CK‐MB) in the CTO group was 75 μg/l (IQR 28‐136) and 51 μg/l (IQR 18–97) in the no‐CTO group (P = 0.021). The presence of a CTO in a non‐IRA in STEMI patients was an independent risk factor for cardiac mortality (HR 2.41, 95% CI: 1.26–4.61, P = 0.008) at 25 months follow‐up. Conclusion: A CTO in a non‐IRA is associated with impaired reperfusion markers and impaired long‐term outcome in STEMI patients. © 2010 Wiley‐Liss, Inc.  相似文献   
110.
Osteonecrosis of the femoral head is the endpoint of a disease process that results from insufficient blood flow and bone-tissue necrosis, leading to joint instability, collapse of the femoral head, arthritis of the joint, and total hip replacement. Pain is the most frequent clinical symptom. Both bone tissue and cartilage suffer when osteonecrosis of the femoral head develops. Stimulation with pulsed electromagnetic fields (PEMFs) has been shown to be useful for enhancing bone repair and for exerting a chondroprotective effect on articular cartilage. Two Italian studies on the treatment of avascular necrosis of the femoral head with PEMFs were presented in this review. In the first study, 68 patients suffering from avascular necrosis of the femoral head were treated with PEMFs in combination with core decompression and autologous bone grafts. The second one is a retrospective analysis of the results of treatment with PEMFs of 76 hips in 66 patients with osteonecrosis of the femoral head. In both studies clinical information and diagnostic imaging were collected at the beginning of the treatment and at the time of follow up. Statistical analysis was performed using chi-square test. Both authors hypothesize that the short-term effect of PEMF stimulation may be to protect the articular cartilage from the catabolic effect of inflammation and subchondral bone-marrow edema. The long-term effect of PEMF stimulation may be to promote osteogenic activity at the necrotic area and prevent trabecular fracture and subchondral bone collapse. PEMF stimulation represents an important therapeutic opportunity to resolve the Ficat stage-I or II disease or at least to delay the time until joint replacement becomes necessary.  相似文献   
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