Enhanced generation of reactive oxygen species and photocatalytic activity by Pt-based metallic nanostructures: the composition matters

The modification of semiconductor nanostructures with metallic nanocomponents can promote the separation of electron/hole from photoexited semiconductors by forming heterojunctions, thus exhibit enhanced photocatalytic activities and potential applications. In this study, Pt-based NPs, including Pt, PtCu, and PtCuCo are employed as model co-catalysts to comparatively study their capability to enhance the photocatalytic activity of TiO₂ nanosheets. It was found that each of Pt, PtCu, and PtCuCo can greatly enhance the photocatalytic activity of TiO₂ toward degradation of organic dyes. Using electron spin resonance spectroscopy, we demonstrated that deposition of Pt-based NPs resulted in more production of reactive oxygen species including hydroxyl radicals, superoxide, and singlet oxygen. The enhancing effects of Pt-based NPs on generation of ROS and photocatalytic activity showed same trend: PtCuCo?>?PtCu?>?Pt. The mechanism underlying the enhancement differences in Pt-based NPs may be mainly related to electronic structure change of Pt in alloying with Cu and Co. These results are valuable for designing hybrid nanomaterials with high photocatalytic efficiency for applications in water purification and antibacterial products.     

Intermittent Internal Fixation With a Locking Plate to Preserve Epiphyseal Growth Function During Limb-Salvage Surgery in a Child With Osteosarcoma of the Distal Femur: A Case Report

Limb shortening is a problem associated with surgery for osteosarcoma of the lower extremity in adolescents, as the tumors frequently occur near the epiphysis. Herein we report the use of a less invasive stabilization system (LISS) and an intermittent fixation method to preserve the growth function of epiphysis in an 11-year-old patient with an osteosarcoma of the distal femur.The 11-year-old male presented with left knee enlargement and pain for 2 weeks, and magnetic resonance imaging (MRI) and biopsy were consistent with osteosarcoma of the left distal femur. After preoperative chemotherapy, en bloc tumor resection was performed with margins based on MRI findings preserving the epiphyseal growth plate, the tumor cavity was filled with inactivated bone and bone cement, and a LISS was used to stabilize the femur. Aggressive postoperative chemotherapy was given. Approximately 105 weeks after surgery radiography showed that the distal end of the plate had moved superior to the epiphysis along with bone growth. Locking screws were placed in the distal part of the LISS plate to stabilize the re-implanted bone, and external fixation was not needed.The patient was able to walk with the crutches 1 week postoperatively, and bear weight on the extremity 6 weeks postoperatively. At 6 years after surgery, the patient''s height had increased 52 cm, shortening of the affected limb was only 1 cm, and the circumference of the affected limb was 2 cm smaller than that of the contralateral limb. There was no significant discomfort in the affected limb, and there was no gait abnormality. The patient could jump and run, and could participate in sports including basketball and badminton to the same degree as his peers.In summary, the novel method of bone reconstruction and fixation provided good results in a child with an osteosarcoma of the distal femur. This fixation method preserves the osteogenic function of the epiphysis and restored bone integrity simultaneously, and provides good functional recovery.     

土耳其斯坦东毕吸虫磷酸丙糖异构酶基因的克隆及其序列分析

目的 克隆土耳其斯坦东毕吸虫磷酸丙糖异构酶的全长基因。方法 根据日本血吸虫和曼氏血吸虫磷酸丙糖异构酶基因的保守区设计引物，利用RT—PCR扩增出土耳其斯坦东毕吸虫磷酸丙糖异构酶基闪的大片段，再结合RACE技术分别得到磷酸丙糖异构酶基因的3’端和5’端，将3部分序列拼接后获得磷酸丙糖异构酶基因全长cDNA序列，并提交GenBank。结果 成功克隆了土耳其斯坦东毕吸虫磷酸丙糖异构酶基因全长cDNA序列并提交GenBank，登录号为DQ092331。结论 土耳其斯坦东毕吸虫磷酸丙糖异构酶基因全长cDNA的克隆为进一步表达及其生物学性能的分析提供了理论基础。     

С��ѪҺϵͳ�������ν�չ

现将2005年我国小儿血液系统疾病的临床进展简述如下。1白血病白血病仍然是威胁我国儿童生命的严重疾病之一。由于社会、文化、经济及治疗条件的限制,儿童白血病坚持正规治疗者仍属少数。汤静燕等[1]随访上海地区(包括外地到沪治疗者)急性淋巴细胞白血病(ALL)244例,66例在诊断后不同时段放弃治疗(依从失败),总依从失败为29·5%,在经济发达的上海地区尚且如此,对于经济欠发达地区由此可见一斑。因此,作者提出应当针对不同地区制定治疗强度减弱的化疗方案,倘若能获得50%~60%的5年无病生存率也是一个进步。该组患儿入院并治疗满15d者164例,治…     

感咳清颗粒的鉴别及稳定性研究

目的 介绍感咳清颗粒的制备、薄层鉴别方法并预测其保质期。方法 以薄荷、黄芩、防风等为原料制备感咳清颗粒剂；参照《中国药典》的方法对该制剂的主药进行薄层定性鉴别；用加速实验法以黄芩苷含量为指标预测了该制剂的稳定性。结果 感咳清颗粒定性鉴别的专属性强；高温加速实验法测得常温下复方制剂以黄芩苷含量为指标的保质期为2年半。结论 该制剂质量稳定可控。     

外科学教学中的审美教育

医学审美教育是医学生全面素质教育不可分割的组成部分,笔者结合长期外科教学实践,阐述了在外科学教学中运用医学美学原理对外科学的美进行开发和挖掘,使医学生在熟练掌握外科学基本理论和基本技能的同时,潜移默化地接受美的教育,美的熏陶,更能激发他们对外科学的热爱和兴趣,达到全面提高医学生整体素质的目的。     

提高肝癌肝移植预后的关键:适应证的选择

我国是世界肝癌发病率最高的国家[1],肝癌治疗中手术切除仍是获得长期生存的最有效措施,但大部分肝癌病人就诊时已属晚期,多伴有严重的肝硬化,或呈多中心发生,能够胜任手术切除的不到10%[2].20世纪60年代肝移植的出现为肝癌治疗带来了新的思路.近年来,肝移植在我国发展迅速,技术日臻成熟,肝移植亦已成为治疗肝癌的一个重要手段.据不完全统计,截止2005年12月,全国累计施行肝移植手术已近10 000例,其中肝癌肝移植约占40%左右[3].随着肝移植数量的增加及经验的积累,国内许多肝移植中心已从既往的一味追求肝移植的“数量”向“数量和质量”并举的方向转变,而肝癌肝移植的适应证问题也逐渐成为争论的焦点.     

大鼠实验性脑出血后血肿周围水通道蛋白-4动态变化的研究

目的研究大鼠脑出血后血肿周围水通道蛋白4(AQP4)的动态变化及其与脑水肿、脑损伤程度的关系。方法采用SD大鼠自体动脉血注入尾状核建立脑出血模型,应用免疫组织化学法、干湿重法、Alexis法分别检测大鼠脑出血后不同时间点血肿周围AQP4、脑组织含水量及神经功能缺损程度的动态变化。结果①血肿周围AQP4在脑出血后12h表达开始增强,1～3d达到高峰,7d后略高于正常,14d基本恢复正常。②脑组织含水量在出血后6h增加,1～3d达到峰值,7d明显减轻,14d基本恢复正常。③神经功能缺损从出血后6h开始,最重的时间点是12h～3d,7d明显减轻,14d基本恢复正常。④脑出血后血肿周围AQP4的表达与脑组织含水量之间存在关联(x2mh=16.49,P<0.05)。⑤脑出血后血肿周围AQP4的表达与神经功能缺损程度之间存在关联(x2mh=15.07,P<0.05)。结论①AQP4的表达与脑水肿、脑损伤的发生发展密切相关,是引起出血性脑水肿脑损伤的重要因素之一。②早期积极控制脑出血后AQP4的过度表达将是减轻和预防脑出血后脑水肿脑损伤的有效途径。     

静脉用免疫球蛋白的治疗作用机制及其不良反应

静脉滴注免疫球蛋白用于多种自身免疫性疾病和炎症性疾病的治疗,其作用机制包括对自身抗体的作用,抑制补体结合,阻止膜攻击复合物形成,调节巨噬细胞Fc受体,抑制致病性细胞因子和其他免疫调节分子等。该药不反应反应较少,主要有皮肤过敏反应、无菌性脑膜炎、血浆黏度增加和血栓形成以及肾功能损害等。