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1.
Abstract— Thymopentin prepared in 5, 15, and 20% 2-hydroxypropyl-β-cyclodextrin (HPCD) was able to inhibit guinea-pig ileum contraction stimulated by anatoxin-a (3 × 10?6 m ) after fourteen months of storage at room temperature. Thus, in contrast to the instability of thymopentin prepared without HPCD, the pharmacological activity was retained and could be stored in a ready-to-use solution for extended periods without refrigeration.  相似文献   
2.
目的:研究视频显示终端(VDT)脉冲磁场对细胞间隙连接通讯功能的影响。方法:用15.6kHz、峰值强度为200 μT的脉冲磁场(PMF)和(或)十四酰基咐拜醇酯(TPA:5 ng/m l)对培养的中国仓鼠肺成纤维细胞(CHL)进行辐射24 h,采用离子电渗注射法观察荧光黄向与其接触的周围细胞的传递情况。结果:TPA对细胞间隙连接通讯(GJIC)功能具有抑制作用,与空白对照组相比有显著差异(P< 0.01),单纯VDT组对GJIC无抑制作用(P> 0.05),亦未见该脉冲磁场对TPA的抑制作用有增强效应。结论:视频显示终端脉冲磁场(15.6 kHz)对细胞间隙连接通讯功能无直接和(或)协同TPA的抑制作用  相似文献   
3.
RF Ablation of Accessory Pathways. Introduction: Catheter ablation may eliminate anterograde and retrograde accessory pathway conduction at closely adjacent but anatomically discrete sites. However, the mechanisms of this discrepancy, the electrophysiologic and anatomical characteristics, and information about systematic study from a large patient population are not available. The purpose of this study was to investigate the electrophysiologic characteristics and anatomical complexities of the accessory pathway in which anterograde and retrograde conduction was successfully ablated at different sites. Methods and Results: Thirty-eight (10.9%) patients (19 men and 19 women; mean age 37 ± 2.4 years) fulfilling the criteria of having separate ablation sites for anterograde and retrograde conduction were designated as group I, and the other 310 patients (215 men and 95 women; mean age 47 ± 0.6 years) were designated as group II. The patients with right-sided free-wall pathways had the highest incidence (18.6%) of separate ablation sites. The anatomical distance between anterograde and retrograde directions (left anterior oblique view. 13 ± 0.6 vs 8 ± 0.9 mm, P < 0.01; right anterior oblique view, 17 ± 0.6 vs 5 ± 0.7 mm, P < 0.01), and incidence of conduction impairment in one direction after successful ablation of another direction (15% vs 78%, P < 0.05) differed significantly between left and right free-wall pathways. The mean distances obtained from left (7 ±0.4 vs 14 ± 0.4 mm, P < 0.05) and right (7 ± 1.1 vs 15 ± 0.9 mm, P < 0.05) anterior oblique views were shorter in patients who had impairment of conduction properties than those in patients without impaired conduction after successful ablation of one direction. Conclusions: This study showed that anatomical and functional dissociation of the accessory pathway into anterograde and retrograde components was possible. Further study on the relation between electropbysiologic and pathologic characteristics would be helpful to confirm these findings.  相似文献   
4.
5.
Juvenile dermatomyositis is a chronic multisystemic disease. It is believed to be of autoimmune aetiology and is characterized by the presence of vasculitis affecting striated muscle and skin. Calcinosis occurs in about 40% of cases. We report a case of a 10‐year‐old girl diagnosed with juvenile dermatomyositis who presented with difficulty in walking and inability to completely extend the four extremities due to calcinosis universalis. Calcinosis had progressed despite a 3‐year administration of diltiazem, hydroxychloroquine, aluminium hydroxide, cyclosporin, and probenecid. The introduction of monthly intravenous immunoglobulin therapy for 15 months lessened disease activity, and markedly regressed calcinosis, and improved functional outcome.  相似文献   
6.
电磁噪声阻断极低频磁场对细胞缝隙连接功能的抑制效应   总被引:7,自引:3,他引:4  
目的 探讨电磁噪声对 5 0Hz磁场诱导的细胞缝隙连接通讯功能 (GJIC)抑制的干预作用。方法 小鼠成纤维细胞 (NIH 3T3)受 5 0Hz 0 .4mT极低频磁场或磁场加同等强度的电磁噪声联合作用 2 4h后 ,在激光共聚焦显微镜下 ,采用荧光光漂白后恢复技术 (FRAP)测定细胞的GJIC功能。结果  0 .4mT磁场单独作用明显抑制细胞的GJIC ,其荧光恢复率为 2 7.6 7%± 5 .12 % ,与对照组(45 .5 7%± 9.72 % )相比 ,差异有显著性 (P <0 .0 1) ;而磁场与电磁噪声联合作用 (5 2 .6 1%± 8.30 % )明显拮抗磁场对GJIC的抑制作用 ,与 0 .4mT磁场组的差异有显著性 (P <0 .0 1) ,并与对照组的差异无显著性 (P >0 .0 5 )。结论 电磁噪声对极低频磁场诱导的GJIC的抑制具有阻断作用  相似文献   
7.
极低频磁场对细胞色素氧化酶亚基1基因转录水平的影响   总被引:3,自引:1,他引:2  
目的 克隆和鉴定本研究室经DD法在Daudi细胞中筛选到的一个极低频磁场的特异反应基因 (MF 1) ,并在多种磁场敏感细胞中证实该基因反应的普遍性 ,为揭示磁场所致生物学效应的作用机制提供实验依据。方法 克隆、序列分析MF 1片段 ;选择HL 6 0、L12 10和中国仓鼠肺成纤维细胞 (CHL)等细胞 ,用Northern技术观察该基因在不同条件的磁场辐照 (5 0Hz磁场 ,磁通密度分别是 0 .1mT和 0 .8mT ,辐照时间分别是 2 0min和 2 4h)后该基因转录水平的变化。结果 克隆测序及与GeneBank同源性比较表明 ,MF 1序列与细胞色素氧化酶亚基 1基因 (CO1)有 10 0 %同源性。HL 6 0、L12 10和CHL等细胞在 0 .1mT、0 .8mT磁场辐照 2 0min后 ,CO1转录水平 (分别为 0 .38± 0 .12、0 .37± 0 .0 4 )均比对照组 (0 .5 8± 0 .12 )下降 ,差异有显著性 (P <0 .0 5 ) ;辐照 2 4h后 ,3种细胞该基因转录水平 (分别为 0 .4 6± 0 .0 9、0 .4 5± 0 .0 9)亦比对照组 (0 .6 5± 0 .0 6 )下降 ,差异有显著性 (P <0 .0 5 )。结论 CO1是磁场辐照密切相关的反应基因之一。磁场可能通过影响CO1的转录水平来影响细胞色素氧化酶的活力 ,从而影响多种生物学效应  相似文献   
8.
Background and objective: The growing burden of COPD in the Asia‐Pacific region supports the need for more intensive research and analysis of the epidemiology of COPD to raise awareness of the disease and its causes, to ensure the development of effective national health policies and to facilitate equitable deployment of finite health‐care resources in the prevention and management of COPD. This study estimated and compared COPD mortality and hospital morbidity rates and trends in these rates over time across countries and regions of Asia‐Pacific. Methods: Data consistent with standard definitions of COPD (ICD‐9/ICD‐10) for the period 1991–2004 were obtained from national health statistics agencies. For countries/regions with complete national mortality and hospitalization data (Australia, Pacific Canada (British Columbia, Hong Kong, South Korea and Taiwan), annual age‐standardized mortality and hospitalization rates were calculated for men and women aged ≥ 40 years. Negative binomial regression modelling was used to estimate rate ratios for country/region, gender and age differences and general trends over time. Results: Mortality rates per 10 000 population ranged 6.4–9.2 in men, 2.1–3.5 in women and 3.7–5.3 overall in 2003. Corresponding ranges for morbidity were 32.6–334.7, 21.2–129 and 28.1–207.3 per 10 000. Trend analysis of data since 1997 produced annual percentage changes in mortality versus hospitalization of ?4.4% versus ?0.7% in Australia, ?3.6% versus 7.5% in Pacific Canada (British Columbia), ?7.15% versus ?5.6% in Hong Kong and ?2.9% versus ?4.2% in Taiwan. Conclusions: In Asia‐Pacific, overall mortality and morbidity rates are high and trends in mortality and morbidity vary between countries/regions. Differences in rates and trends for men and women most likely reflect the different trends in historical and prevalent smoking profiles for COPD in the different countries and regions.  相似文献   
9.
RF Catheter Ablation of Clockwise Atrial Flutter. introduction: Although the mechanism and radiofrequency catheter ablation of counterclockwise (typical) atrial flutter have been studied extensively, information about the electrocardiographic and electropbysiologic characteristics and effects of radiofrequency ablation in patients with clockwise atrial flutter is limited. Methods and Results: Thirty consecutive patients with clinically documented paroxysmal clockwise atrial flutter were studied. Endocardial recordings and entrainment study using a “halo” catheter with 10 electrode pairs in the right atrium were performed. Radiofrequency energy was applied to the inferior vena cava-tricuspid annulus (IVC-TA) and/or coronary sinus ostium-tricuspid annulus (CSO-TA) isthmus to evaluate the effects of linear catheter ablation. Eighteen patients had both counterclockwise and clockwise atrial flutters, and 12 patients had only clockwise atrial flutter. Both forms of atrial flutter had similar flutter cycle lengths (232 ± 30 vs 226 ± 25 msec, P = 0.526) but reverse activation sequences. Right atrial pacing at a cycle length 20 msec shorter than the flutter cycle length from the CSO-TA isthmus, IVC-TA isthmus, and the area between the two isthmuses revealed concealed entrainment with stimulus-to-P wave intervals of 32 ± 19, 95 ± 14, and 50 ± 17 msec (P = 0.022) in the counterclockwise form, and 110 ± 12, 40 ± 20, and 60 ± 15 msec (P = 0.018) in the clockwise form. In clockwise atrial flutter, 20 patients with biphasic P waves in the inferior leads had the presumed exit site of slow conduction area located at the low posterolateral right atrium; 10 patients with positive P waves in the inferior leads had the presumed exit site located at the mid-high posterolateral right atrium. Among the 18 patients with both forms of atrial flutter, linear ablation lesions directed at the IVC-TA isthmus eliminated both forms of atrial flutter in 14 patients; in the remaining 4 patients. CSO-TA linear lesions eliminated the counterclockwise form and IVC-TA lesions eliminated the clockwise form. Among the 12 patients with the clockwise form only, CSO-TA linear lesions eliminated flutter in 2 and IVC-TA linear lesions eliminated flutter in 10 patients. Successful ablation was confirmed by creation of bidirectional conduction block in the IVC-TA and/or CSO-TA isthmus during pacing from the proximal coronary sinus and right posterolateral atrium sandwiching the linear lesions. During the follow-up period of 17 ± 8 months, 2 patients had recurrence of clockwise atrial flutter, 1 patient had new onset of atypical atrial flutter, and 2 patients had new onset of atrial fibrillation. Conclusions: Counterclockwise and clockwise atrial flutters may have overlapping slow conduction areas with different exit sites. Radiofrequency catheter ablation using the linear method directed at the IVC-TA and CSO-TA isthmuses was feasible and effective in treating both forms of atrial flutter.  相似文献   
10.
Gender Differences in Patients With AVNRT. Introduction: The detailed electrophysiological characteristics of the gender differences associated with atrioventricular nodal reentrant tachycardia (AVNRT) have not been clarified. This study investigated the gender‐related electrophysiological differences in a large series of patients undergoing radiofrequency catheter ablation. Methods and Results: A total of 2,088 consecutive AVNRT patients (men/women 869/1,219) who underwent catheter ablation were enrolled in this study. We evaluated the gender differences in their electrophysiological characteristics. Women had a significantly younger age of onset, higher incidence of multiple jumps, shorter AH interval, atrial effective refractory period (ERP), anterograde fast pathway ERP, anterograde slow pathway ERP, and retrograde slow pathway ERP, and longer ventricular ERP than men. The incidence of baseline ventriculoatrial dissociation was lower in women than in men. Women needed less isoproterenol/atropine to induce AVNRT. No gender differences in the radiation exposure time, procedure time, complication rate, acute success rate, or second procedure rate were noted. Both typical and atypical AVNRT were more predominant in women. In the patients with atypical AVNRT, there was no significant gender difference in incidence of baseline ventriculoatrial dissociation; however, the retrograde slow pathway ERP was significantly shorter in women than in men. Women of premenopausal age (≤50 years old) had a significantly higher incidence of anterograde multiple jumps and a retrograde jump phenomenon, and a shorter anterograde slow pathway ERP and retrograde slow pathway ERP than those of women over 50 years old. Conclusion: Gender differences in the anterograde and retrograde AV nodal electrophysiology were noted in the patients with AVNRT. (J Cardiovasc Electrophysiol, Vol. 21, pp. 1114‐1119)  相似文献   
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