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101.
A body of evidence suggests that ethanol can lead to damage of neuronal cells. However, the mechanism underlying the ethanol-induced damage of neuronal cells remains unclear. The role of mitogen-activated protein kinases in ethanol-induced damage was investigated in SK-N-SH neuroblastoma cells. 3-[4,5-Dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide cell viability assay, DNA fragmentation detection, and flow cytometric analysis showed that ethanol induced apoptotic cell death and cell cycle arrest, characterized by increased caspase-3 activity, DNA fragmentation, nuclear disruption, and G1 arrest of cell cycle of the SK-N-SH neuroblastoma cells. In addition, western blot analysis indicated that ethanol induced a lasting increase in c-Jun N-terminal protein kinase activity and a transient increase in p38 kinase activity of the neuroblastoma cells. c-Jun N-terminal protein kinase or p38 kinase inhibitors significantly reduced the ethanol-induced cell death. Ethanol also increased p53 phosphorylation, followed by an increase in p21 tumor suppressor protein and a decrease in phospho-Rb (retinoblastoma) protein, leading to alterations in the expressions and activity of cyclin dependent protein kinases. Our results suggest that ethanol mediates apoptosis of SK-N-SH neuroblastoma cells by activating p53-related cell cycle arrest possibly through activation of the c-Jun N-terminal protein kinase-related cell death pathway.  相似文献   
102.

Background

Hepatoblastoma is a rare tumour accounting for approximately 1% of all paediatric malignancies. Hepatoblastoma complicated by pulmonary metastatic disease continues to cause management difficulties due to a lack of robust evidence and treatment guidelines.

Method

This series is the experience of a tertiary paediatric referral centre. Patients were prospectively enlisted, and their charts were retrospectively reviewed.

Results

Thirty-seven patients were treated for hepatoblastoma from 1995 to 2012 inclusive. The overall survival was 34/37(91.9%). Eight patients had lung metastases at diagnosis (LMD) and twenty-nine did not (NLMD). Two-year EFS was 62.5% in the LMD group and 89.3% in the NLMD group (p = 0.078). Overall survival in the LMD and NLMD groups was 100% and 89.7%, respectively (p = 0.389). Two patients in the LMD group required multiple thoracic resections to achieve cure. Within the NLMD group, two patients developed lung metastases whilst on treatment, and both of these patients died.

Conclusion

In this series, children presenting with lung metastases had a higher risk of relapse but excellent overall survival. However, children who developed pulmonary disease during treatment had a poor prognosis. We advocate aggressive surgical treatment of pulmonary hepatoblastoma to achieve cure.  相似文献   
103.
104.
This study aimed to determine whether (1) cognitive behavioural therapy with behavioural analysis for insomnia (CBTi-BA) is more effective for insomnia and co-morbid depressive symptoms than treatment as usual (TAU) and (2) whether CBTi-BA promotes earlier reduction of the daily dose of hypnotic medication in chronic insomnia resistant to pharmacological treatment. A total of 63 patients with chronic insomnia aged 20–77 years who already received hypnotic medication regularly were assigned to two interventions: combined therapy or TAU alone. The subjects provided demographic information and completed self-rating scales for insomnia and depressive symptoms. After treatment, the combined therapy group showed significant decreases in the symptoms of both insomnia and depression and significant reductions in the daily dose of hypnotic medication compared with the group receiving TAU alone. In the combined therapy group, 71% of the participants reported a reduction in insomnia to normal levels and 79% succeeded in decreasing the daily dose of hypnotics to 50% or less of the baseline dose. These results revealed that CBTi-BA can reduce insomnia and depressive symptoms as well as the daily dose of hypnotic medication in patients with chronic insomnia resistant to pharmacological treatment.  相似文献   
105.
106.
目的通过分析肝移植术后中期血流动力学的规律,探讨其与肝功能的关系。方法以2014年2月至2015年10月于青岛大学附属医院进行肝移植手术的56例肝移植受者为研究对象,按肝功能正常与否分为正常组(24例)和异常组(32例)。记录两组的一般资料及肝功能,并应用超声检测其肝移植术前及术后1、30、90 d的肝动脉峰值血流速度(HAP)、门静脉峰值血流速度(PVP)、门静脉灌注量(PVF)等,并计算肝动脉缓冲能力(BC)、校正BC等。对两组间肝脏血流动力学因素与肝功能关系进行单因素和多因素分析,并绘制受试者工作特征(ROC)曲线。结果异常组中移植术后30 d的PVP、PVF明显高于正常组(P=0.014、0.049),正常组中BC及校正BC明显高于异常组(P=0.048、0.011)。多因素分析显示校正BC是其独立危险因素(P=0.047),ROC曲线下面积(AUC)为0.705,灵敏度为0.652,特异度为0.750。结论肝移植术后30 d的PVP、PVF、BC及校正BC可能与肝功能异常有关,其中校正BC可作为诊断及干预肝功能异常的指标之一。  相似文献   
107.
Gossypol, a polyphenolic dialdehyde toxin isolated from cotton seed, has anti‐cancer properties and has recently shown some success in the treatment of glioma. Its effects on brain neurons and blood vessels are poorly understood. In this work we examined the effects of gossypol on cytosolic Ca2+ concentration ([Ca2+]i) of mouse brain bEND.3 endothelial cells. Cell viability tests revealed that after 3 hour and 18 hour exposures, 10 µmol/L gossypol caused 23% and 65% cell death, respectively; 3 µmol/L gossypol caused no and 21% cell death, respectively. [Ca2+]i was raised concentration‐dependently by 1‐10 µmol/L gossypol. We then explored the Ca2+ signalling triggered by 3 µmol/L gossypol, which inflicted minimal toxicity: the Ca2+ signal was composed largely of Ca2+ influx and to a small extent, intracellular Ca2+ release. Such Ca2+ influx was much larger than store‐operated Ca2+ influx triggered by maximal Ca2+ pool depletion. The Ca2+ influx triggered by 3 and 10 µmol/L gossypol caused NO release and cell death, respectively. Gossypol also triggered influx of Mn2+ and Na+, but not Ni2+ and Co2+. Gossypol‐triggered Ca2+ signal was inhibited only by 14% and 37% by 100 µmol/L La3+ and 10 µmol/L nimodipine, respectively; and not suppressed at all by 5 mmol/L Ni2+. Gossypol‐triggered Ca2+ signal was suppressed by 78% by 30 µmol/L ruthenium red, suggesting gossypol may act on TRPV channels. Our results suggest gossypol triggered opening of a non‐selective cation pore, possibly a member of the TRPV family.  相似文献   
108.
钙离子(Ca2+)是细胞内重要的第二信使,其主要储存在内质网和线粒体中,参与调控细胞多种生理功能及维持内质网、线粒体功能。内质网和线粒体对钙离子的摄取与释放直接影响胞内钙离子水平的变化,继而影响细胞正常生理功能。病理条件下,细胞内钙离子稳态失衡,可引发细胞生理功能异常并进一步影响内质网、线粒体功能。非酒精性脂肪肝(NAFLD)是临床常见病和多发病,其主要病理特征是:肝脏脂肪样变性、内质网应激、线粒体损伤和非特异性炎性反应等。其中持续的内质网应激及线粒体功能障碍是NAFLD发生发展的重要诱因。而细胞内钙稳态的变化可直接导致内质网及线粒体功能异常,继而影响NAFLD的发生发展。本文主要从钙稳态的主要影响因素以及钙稳态变化与NAFLD的关系两方面进行阐述,为寻求和研发防治NAFLD的药物提供新的方向。  相似文献   
109.
目的 探索小鼠放射性肺损伤模型中大批量、快速、低成本实现全肺野精准照射的有效方法,普及这一重要放射生物学模型在多领域的应用。方法 采用8~10周龄C57BL6雌性小鼠,使用micro-CT三维重建图像进行肺部解剖学参数测量并确定放射野范围(n=12)。结合标准化胸腔暴露及固定、无创通气麻醉等手段建立"一体化"麻醉、固定、定位装置,借助常规医用直线加速器完成批量小鼠精准肺野照射。结果 小鼠CT图像三维重建后在冠状位与矢狀位图像上确定肺结构的解剖位置与尺寸平均值。并进一步根据小鼠呼吸频率及幅度确定受呼吸频率影响的肺野上界、中线和下界,并将测量值标记于专门设计的肺野照射装置用来指导实际操作。本装置大致可分为小鼠固定架和麻醉通气系统两部分构成。固定架用以安置每排10只小鼠用弹力栓妥善固定暴露胸腔。照射中通过麻醉面罩全程给予异氟烷混合气体,确保实验过程中小鼠处于深度麻醉以及均匀呼吸动度。结论 本研究设计的集麻醉、固定、定位为一体的"弹匣式"小鼠肺野照射装置,可显著增加胸部放射实验的准确性、简易性、安全性、稳定性和高效性。大幅减低实验成本和对高端辐照设备的依赖,具有一定的实际应用及推广价值。  相似文献   
110.
目的 考察3种方法制备扎那米韦鼻用粉雾剂粉体的性质。方法 分别采用研磨法、气流粉碎法和喷雾干燥法制备不同粒径扎那米韦的粉体,并与吸入乳糖混合,对混合粉体的粒径、微观形态、流动性、堆密度和吸湿性进行考察。结果 研磨法、喷雾干燥法和气流粉碎法得到的扎那米韦原料粉末粒径依次减小;与乳糖相比,3种混合粉体松密度逐渐减小,振实密度依次增加,流动性仅喷雾干燥略增加,研磨法和气流粉碎法无影响; 3种方式得到的混合粉末均没有明显的吸湿性。结论 研磨筛分法比较适合扎那米韦鼻用粉雾剂的进一步开发。  相似文献   
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