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11.
创伤后的神经胶质增生导致硫酸软骨素蛋白聚糖(CSPG)的显著表达,从而抑制轴突生长和再生。甲基强地松龙(MP),一种合成的糖皮质激素,在急性脊髓损伤(SCI)的治疗中有神经保护作用和抗炎效应。但是,MP对于CSPG在活性胶质细胞中的表达的作用尚不清楚。本文用a-氨基-3-羟基-5-甲基-4-异恶唑丙酸酯(AM-PA)诱导星形胶质细胞再活化,用环噻嗪模拟SCI的兴奋性中毒刺激。AMPA治疗后,星形胶质细胞再活化的标志物-胶质纤维酸性蛋白(GFAP)、CSPG神经聚糖和磷酸盐的表达都显著上调。AMPA治疗星形胶质细胞的条件培养液强烈抑制大鼠背根神经节中神经元的轴突生长,但这种作用能被MP的预处理所逆转。此外,MP下调成年SCI大鼠中GFAP和CSPG的表达,对抗RU486的糖皮质激素受体(GR)和GR si RNA能逆转MP对GFAP和神经聚糖表达的抑制作用。这些结果提示,MP能在兴奋性中毒损伤后通过GR介导的星形胶质细胞再活化下调和GSPG表达抑制来改善神经修复,促进轴突生长。  相似文献   
12.
Unipolar Characteristics of CFAEs. Background: The noncontact mapping (NCM) system possesses the merit of global endocardial recording for unipolar and activation mapping. Objective: We aimed to evaluate the unipolar electrogram characteristics and activation pattern over the bipolar complex fractionated atrial electrogram (CFAE) sites during atrial fibrillation (AF). Methods: Twenty patients (age 55 ± 11 years old, 15 males) who underwent NCM and ablation of AF (paroxysmal/persistent = 13/7) were included. Both contact bipolar (32–300 Hz) and NCM virtual unipolar electrograms (0.5–300 Hz) were simultaneously recorded along with the activation pattern (total 223 sites, 11 ± 4 sites/patient). A CFAE was defined as a mean bipolar cycle length of ≤ 120 ms with an intervening isoelectric interval of more than 50 ms (Group 1A, n = 63, rapid repetitive CFAEs) or continuous fractionated activity (Group 1B, n = 59, continuous fractionated CFAEs), measured over a 7.2‐second duration. Group 2 consisted of those with a bipolar cycle length of more than 120 ms (n = 101). Results: The Group 1A CFAE sites exhibited a shorter unipolar electrogram cycle length (129 ± 11 vs 164 ± 20 ms, P < 0.001), and higher percentage of an S‐wave predominant pattern (QS or rS wave, 63 ± 13% vs 35 ± 13%, P < 0.001) than the Group 2 non‐CFAE sites. There was a linear correlation between the bipolar and unipolar cycle lengths (P < 0.001, R = 0.87). Most of the Group 1A CFAEs were located over arrhythmogenic pulmonary vein ostia or nonpulmonary vein ectopy with repetitive activations from those ectopies (62%) or the pivot points of the turning wavefronts (21%), whereas the Group 1B CFAEs exhibited a passive activation (44%) or slow conduction (31%). Conclusions: The bipolar repetitive and continuous fractionated CFAEs represented different activation patterns. The former was associated with an S wave predominant unipolar morphology which may represent an important focus for maintaining AF. (J Cardiovasc Electrophysiol, Vol. 21, pp. 640‐648, June 2010)  相似文献   
13.
Background: The left atrial (LA) size is an important predictor of atrial fibrillation (AF) procedural termination and the long-term outcome. We sought to evaluate the long-term outcome in regard to the LA size and procedural termination.
Methods: Eighty-seven consecutive chronic AF patients (72 males, 53 ± 10 years) underwent 3D mapping (NavX) and ablation. A stepwise approach including circumferential pulmonary vein (PV) isolation, linear ablation, and continuous complex-fractionated electrogram (CFE) ablation (targeting fractionation intervals of < 50 ms). Electrical cardioversion was applied to those without any procedural termination. The freedom from AF was defined as the maintenance of sinus rhythm without the use of any class I or III antiarrhythmic drugs after the blanking period.
Results: Among the 87 patients, all received a circumferential PV isolation, 93% a linear ablation, and 59% a continuous CFE ablation. Those with AF procedural termination (n = 30) had a better long-term outcome when compared with those without termination during a follow-up of 21 ± 12 months. Moreover, a Kaplan-Meier analysis showed that in those with an LA diameter of less than 45 mm (n = 49), the freedom from AF rate was higher when procedural termination was achieved (P = 0.004). On the contrary, the outcome was comparable in those with an LA diameter of ≥ 45 mm (n = 38), whether AF procedural termination occurred or not (P = 0.658).
Conclusions: AF procedural termination was related to the long-term success during chronic AF ablation, especially in those with an LA diameter of less than 45 mm. The favorable effect of termination decreased when the LA diameter was ≥ 45 mm.  相似文献   
14.
15.
To assess whether the hepatitis C virus plays an important role in Chinese patients with acute and chronic liver disease, antibodies to HCV (anti-HCV) were measured by enzyme immunoassay in 67 patients with type A and B acute viral hepatitis, 165 patients with non-A, non-B (NANB) hepatitis, 438 patients with chronic hepatitis, 200 patients with postnecrotic liver cirrhosis, 72 patients with alcoholic liver disease, 55 patients with non-alcoholic fatty liver, 24 patients with toxic and drug-induced hepatitis, and 20 patients with other chronic liver diseases. Anti-HCV was not detected in sera from patients with type A and B acute viral hepatitis, toxic and drug-induced hepatitis, primary biliary cirrhosis, Wilson's disease, or lupoid hepatitis. The anti-HCV prevalence was found to be highest in patients with NANB hepatitis (59% in sporadic and 73.2% in transfusion-associated), 16.4% in non-alcoholic fatty liver, 5.6% in alcoholic liver disease, 6.8% in chronic hepatitis, and 16% in postnecrotic liver cirrhosis. In patients with chronic hepatitis, the anti-HCV prevalence was significantly higher in HBsAg-negative (15/34, 44.1%) than in HBsAg-positive cases (15/404, 3.7%; P less than 0.0001). The results indicate that HCV is a major agent of NANB hepatitis and plays an important role in HBsAg-negative chronic liver disease in Taiwan.  相似文献   
16.
Abstract A transjugular liver biopsy was performed on 60 patients. Specimens were successfully obtained from 57 (95%) patients. Specimens obtained from cirrhotic patients were frequently small-sized/fragmented. The wedge hepatic venous pressure and hepatic venous pressure gradient were higher in patients with small-sized/fragmented specimens than those with non-fragmented specimens (16.3 ± 6.4 vs 12.3 ± 4.9 and 10.9 ± 6.2 vs 7.3 ± 3.4 mmHg, P <0.05, respectively). During the same period of time, percutaneous liver biopsies were consecutively performed on 277 patients. The liver specimens by transjugular method were generally smaller (0.63±0.58 vs 1.50±0.86 cm, P <0.001) and more fragmented (63% vs 16%, P <0.01) than those obtained by percutaneous method. Biopsy specimens obtained for diagnosis by the former method were inadequate from 6 (10%) patients and by the latter route were inadequate from 7 (2%) patients. Subcapsular haematoma in one patient was associated with the transjugular liver biopsy. Minor complications occurred in three patients: neck haematoma in two and paroxysmal supraventricular tachycardia during the procedure in one. In comparison, percutaneous liver biopsy was followed by minor complications in 20 patients and major complications in four patients. It is concluded that transjugular liver biopsy is a safe, valuable and alternative procedure to obtain liver specimens, especially in patients who were contraindicated for percutaneous liver biopsy.  相似文献   
17.
Abstract The relationship between the severity of cirrhosis and systemic and hepatic haemodynamic values was evaluated in 193 patients with cirrhosis, most of whom were diagnosed with post-necrotic cirrhosis. It was found that the hepatic venous pressure gradient and cardiac output in Pugh's A patients (13.6 ± 4.8 mmHg and 6.2 ± 1.6 L/min, mean ± s.d.) were significantly lower than in both Pugh's B (16.8 ± 4.3 mmHg and 7.3 ± 2.1 L/min) and Pugh's C (18.8 ± 5.5 mmHg and 7.4 ± 2.3 L/min) patients ( P < 0.01), respectively. In contrast, the systemic vascular resistance in Pugh's A patients (1232 ± 369 dyn/s per cm5) was significantly higher than in both Pugh's B (1016 ± 345 dyn/s per cm5) and Pugh's C (935 ± 234 dyn/s per cm5) patients ( P < 0.01), respectively. Additionally, not only was there a positive correlation found between Pugh's score and cardiac output and hepatic venous pressure gradient, but a negative correlation was found between Pugh's score and systemic vascular resistance. It was also confirmed that the degree of portal hypertension and the hyperdynamic circulation were more severe in patients with ascites than in those without ascites. However, there were no statistically significant differences in hepatic venous pressure gradient among patients with F1, F2 and F3 esophageal varices (15.7 ± 4.0, 17.0 ± 4.8 and 18.0 ± 4.8 mmHg, respectively). It is concluded that in those patients with cirrhosis, the severity of cirrhosis is closely related to the degree of the hyperkinetic circulatory state and portal hypertension.  相似文献   
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19.
The types of workplaces and occupations with coronavirus 2019 (COVID-19) clusters vary between countries and periods. We aimed to characterize major occupational groups with mass outbreaks of COVID-19 infections in several Asia-Pacific countries. Data on the major occupations or workplaces reporting COVID-19 cases in workplaces from January 2020 to July 2021 was collected from industrial hygiene professionals in nine countries. The proportion of workers accounted for 39.1 to 56.6% of the population in each country. The number of workers covered in the national statistics varies among nations based on their definition of a worker. None of the countries examined here have systematically collected occupational data on COVID-19 illnesses and deaths classified by type of industry, occupation, or job. Most countries experienced COVID-19 clusters among health and social care workers (HSCW) in hospitals or long-term care facilities. The types of occupations or workplaces with virus clusters in some participating countries included prisons, call centers, workplaces employing immigrants, garment facilities, grocery stores, and the military, which differed among countries, except for a few common occupations such as HSCW and those populated by immigrants. Further study is necessary in order to seek ways to control infection risks, including revisions to industrial-health-related laws.  相似文献   
20.
目的急性心肌炎并发心衰竭可能因为封药物和动脉汽球帮浦反应不佳而死于心因性休克,目前许多文献支持使用体外循环机维持身体的机能,度过危险期,然而,再合并使用具抗发炎与抗凝血作用的“蛋白质C”制剂,提高急性心肌炎并发心衰竭的疗效则仍有待观察。本文描述四例病毒性心肌炎治疗情形,藉以探讨体外循环机合并蛋白质C"制剂的疗效。方法2003年以来,本院陆续有四例病毒性心肌炎病人因为并发心衰竭而接受重症加护单位住院治疗,分别是二男二女,平均年龄37.2岁,发病前分别都有数天类流感症状,如发烧、胸痛和呼吸困难等,住院时胸部X光都呈现心脏扩大和两侧肺野浸润,虽然心电图显示ST上升,但是心导管摄影都排除心肌梗塞的可能,心脏超音波的左心室功能严重受损,住院初期虽然使用多种强心剂,病人仍并发呼吸衰竭和其它器官衰竭,其中两位病人接受体外循环机合并蛋白质C"制剂的治疗,另一男性只接受蛋白质C"制剂的治疗,以及一女性只接受体外循环机的治疗。结果所有接受蛋白质C"制剂的治疗的三位病人都顺利脱离体外循环机和呼吸器,左心室功能也都恢复正常,出院後追踪并无发现任何神经学或其它後遗症,其中只接受体外循环机的治疗的女性因为红斑性狼沧病发症和感染而死亡;血清学证实其中三位为Parvovirus B19感染所致心肌炎。结论对于濒临死亡的急性心肌炎并发心衰竭的病患,特别是病毒性的致病源,合并“蛋白质C”制剂和体外循环机的治疗似乎有正面的意义。  相似文献   
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