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81.
为了探讨局部麻醉和模拟定位机引导在集束巨能刀治疗肺癌的射频治疗的适应证、治疗效果以及并发症的预防和处理,采用0.5%普鲁卡因局部浸润麻醉,模拟定位机引导下经皮穿刺集束巨能刀治疗肺癌46例。CT显示条索状瘢痕残余ll例,空洞形成或直径缩小32例,无变化1例,增大2例。治疗中患者均有不同程度的胸腔内热感及短时间内可以忍受的疼痛感。并发症包括气胸7例、皮下气肿5例、发热24例、咯血13例和慢性支气管炎急性发作4例。初步研究结果提示,集束巨能刀射频治疗周围型肺癌疗效满意,尤其适用于直径〈3cm的肿瘤。局部麻醉配合全身止痛药物应用可以很好地解决治疗中的疼痛问题,与全麻相比还具有省时省力、费用低的优势;对于周围型肺癌,模拟定位机引导经皮穿刺定位与CT引导相比,同样准确、安全,但操作更为方便。 相似文献
82.
RNA干扰基因敲除MAGE-1在恶性胶质瘤U87细胞中的初步研究 总被引:4,自引:4,他引:0
目的:通过构建抑制MAGE-1的短片段双链核糖核酸(siRNA)表达载体,鉴定其在人恶性胶质瘤细胞系U87细胞中对MAGE.1基因表达的干涉作用。方法:化学合成2对编码短发夹RNA序列的靶向MAGE—1基因寡核苷酸链,克隆至经BglⅡ、HindⅢ双酶切的pSUPER载体上,重组构建核糖核酸干扰(RNAi)质粒载体。利用RT-PCR、流式细胞术和荧光显微镜,检测经稳定转染后胶质瘤U87细胞中MAGE-1的表达,以了解siRNA的干涉效果。结果:重组构建的pSUPER—MAGE—1载体经双酶切、电泳及插入基因片段序列分析,表明寡核苷酸链成功地插入至预计位点,且序列与预期完全一致。稳定转染后G418筛选出的U87多克隆细胞MAGE-1的表达经RT—PCR、流式细胞术和荧光显微镜检测,2对siRNA均有较明显的干扰作用。结论:载体的成功构建并能对U87细胞中的MAGE—1分子进行RNAi,为进一步研究MAGE—1在肿瘤中的作用,分析基因功能,展开肿瘤基因治疗奠定了基础。 相似文献
83.
T-2 toxin induces apoptosis, and selenium partly blocks, T-2 toxin induced apoptosis in chondrocytes through modulation of the Bax/Bcl-2 ratio. 总被引:6,自引:0,他引:6
Jinghong Chen Yonglie Chu Junling Cao Zhantian Yang Xiong Guo Zhilun Wang 《Food and chemical toxicology》2006,44(4):567-573
T-2 toxin is one of the mycotoxins, a group of type A trichothecenes produced by several fungal genera including Fusarium species. In the present study, we have investigated the apoptotic effects of T-2 toxin on chondrocytes and the relationship between T-2 toxin induced chondrocyte apoptosis and its influence on Bcl-2/Bax protein and mRNA expression. We have also examined the inhibitory effects of selenium on chondrocyte apoptosis induced by T-2 toxin. We have combined morphological and biological techniques to establish the relevance of apoptosis in human chondrocyte death induced by T-2 toxin. Treatment with T-2 toxin caused accelerated apoptosis in a concentration dependent manner. The apoptosis induced by T-2 toxin involved an increased Bax/Bcl-2 ratio. Bcl-2 mRNA expression remained unchanged in chondrocyte apoptosis induced by T-2 toxin treatment, while Bax mRNA expression increased following treatment with T-2 toxin. Selenium could partly block the apoptosis of chondrocytes induced by T-2 toxin through decreasing the Bax/Bcl-2 ratio. These results suggest that, under our experimental conditions, apoptosis of chondrocytes can be induced by T-2 toxin (1-20ng/mL) via the Bcl-2 and Bax proteins, and the Bax/Bcl-2 ratio may play a critical role in governing the susceptibility to apoptosis induced by T-2 toxin in human chondrocytes. 相似文献
84.
近几年来,我所党委一班人始终坚持党对单位的政治领导,加强班子建设,振奋精神,团结协作,不断深化人事分配制度改革,大力调动广大干部职工的积极性,有力地推动了全所各项工作快速发展。我们的主要做法是“四讲、四提高”。 相似文献
85.
86.
纳米血管生成素-2小干扰RNA质粒制备及功能研究 总被引:2,自引:0,他引:2
[目的]制备血管生成素-2小干扰RNA(Ang-2siRNA)质粒纳米微粒,并观察其基因转染能力和基因沉默效果.[方法]应用分子克隆的方法构建Ang-2siRNA质粒,将其与聚乳酸、O羧甲基壳聚糖用水/油/水(W/O/W)双乳化溶剂蒸发法制备纳米微球,扫描电镜观察其形态和粒径.然后转染原代人脐带静脉内皮细胞,观察纳米Ang-2siRNA微粒干扰Ang-2基因表达的效果及其细胞保护功能.[结果]扫描电镜观察到Ang2siRNA纳米微球呈球形和椭球形,粒径150~200 nm,大小分布均匀,包封完整,分散性良好.有较强转基因能力,良好的RNA干扰效果和血管内皮细胞保护功能.[结论]成功制备纳米Ang-2siRNA微粒,并证实其载基因能力和RNA干扰效果,对血管内皮细胞损伤因素有良好保护作用,为进一步研究心肌梗死的血管修复机制奠定了坚实的基础. 相似文献
87.
聚磷酸钙纤维和左旋聚乳酸软骨支架复合自体骨髓间充质干细胞构建组织工程化人工关节软骨 总被引:1,自引:0,他引:1
目的应用组织工程学技术,体外初步构建组织工程化人工关节软骨。方法制备三维多孔软骨支架材料CPP/PLLA,体外诱导兔MSCs向软骨细胞表型分化,免疫组织化学染色检测软骨特异性Ⅱ型胶原表达,将诱导细胞与软骨支架材料CPP/PLLA复合,体外培养构建人工关节软骨,1周后终止培养,扫描电镜观察组织工程化人工软骨的微观结构;同时将构建人工软骨移植于兔大腿皮下,3周后处死动物,甲苯胺蓝染色观察。结果扫描电镜观察可见该复合材料CPP/PLLA为高孔隙率的网状、连通、微孔结构,微孔分布均匀,孔径大小为300~400Ⅳn之间;兔MSCs经体外软骨表型定向诱导后,Ⅱ型胶原免疫组化染色阳性。诱导后的MSCs可在支架材料内良好贴附生长,细胞被分泌的胶原基质包裹;从体内获取的培养物组织切片观察可见大量的软骨细胞生成,甲苯胺蓝染色阳性。结论经软骨起源诱导后的MSCs与CPP/PLLA复合培养可以构建自体软骨移植的替代物,为应用软骨组织工程方法修复关节软骨缺损和功能重建提供一种新材料,具有较大的潜在应用价值。 相似文献
88.
脂肪抽吸术对胰岛素敏感性及脂质代谢的影响 总被引:2,自引:1,他引:1
目的了解脂肪抽吸术对胰岛素抵抗与脂质代谢的影响,并探讨其临床意义。方法对20例接受腹部脂肪抽吸术者术前及术后2个月的血清三酰甘油、总胆固醇、高密度脂蛋白胆固醇、低密度脂蛋白胆固醇,胰岛素敏感性进行测量并进行比较。结果术后与脂肪抽吸术前比较,术后胰岛素敏感性增强(P〈0.01),血清总胆固醇与低密度脂蛋白胆固醇水平下降。结论腹部脂肪抽吸术在去除大量皮下脂肪的同时,对胰岛素抵抗、脂质代谢等心脑血管危险因素也有非常有益的影响。 相似文献
89.
BACKGROUND: As a non-invasive technique which can provide comprehensive biological information, 1H-magnetic resonance spectroscopy (1H-MRS) may provide valuable reference data for irreversible recovery or reversible changes in ischemic tissue after stroke.
OBJECTIVE: To monitor and evaluate the effect of the urokinase thrombolytic therapy after experimental acute cerebral ischemia by 1H-MRS technology and investigate its adaptability.
DESIGN: Randomly controlled animal study.
SETTINGS: Shenzhen Hospital of Peking University and National Key Laboratory of Pattern and Atom & Molecular Physics, Wuhan Physics and Mathematics Institute, Chinese Academy of Science.
MATERIALS: Eleven healthy adult Sprague-Dawley (SD) rats, weighing 260–300 g and of both genders, were supplied by Experimental Animal Center of Tongji Medical Collage, Huazhong University of Science and Technology [SCXK (e) 2004-007]. 4.7T superconducting nuclear magnetic resonance meter was provided by Brucker Company.
METHODS: The experiment was carried out in Shenzhen Hospital of Peking University and National Key Laboratory of Pattern and Atom & Molecular Physics, Wuhan Physics and Mathematics Institute, Chinese Academy of Science from August 2003 to December 2005. ① The rats were randomly divided into 30-minute self-thrombo-embolism group (n =6) and 60-minute self-thrombo-embolism group (n =5). Six rats in 30-minute self-thrombo-embolism group were occluded with clot embolus for 30 minutes and 5 rats in 60-minute self-thrombo-embolism group were occluded for 60 minutes. 10 000 U/kg urokinase was dissolved in 2 mL saline and the operation lasted for 5 minutes. ② 1H-MRS was performed before thrombolysis and at 3 hours and 24 hours after successful embolization. The metabolic changes of N-acetyl-L-aspartic acid (NAA)/phosphocreatine (PCr) + creatine (Cr), choline phosphate (Cho)/PCr+Cr and lactic acid (Lac)/PCr+Cr in the region of interests were analyzed. ③ The T2W image was conducted 24 hours after the thrombolytic therapy with TR=500 ms and TE=25 ms. ④ The subjects were sacrificed immediately after 1H-MRS and the brain tissues were cut into pieces and stained with HE method; in addition, pathological changes were observed under optic microscope.
MAIN OUTCOME MEASURES: ① Metabolic changes of NAA/PCr+Cr, Cho/PCr+Cr and Lac/PCr+Cr in the region of interests; ② T2W image at 24 hours after the thrombolysis; ③ pathological observation of brain tissue.
RESULTS: Eleven rats were all involved in the final analysis. ① Metabolic changes in the region of interests : In 30-minute self-thrombo-embolism group, the Lac peak emerged immediately after the embolism, but the ischemic zone decreased 3 hours after the thrombolytic therapy (0.252±0.01, 0.603±0.01, P < 0.01). Lac/(PCr+Cr) ratio was 0.290±0.01 at 24 hours after thrombolysis, which was higher than that at 3 hours after thrombolysis (P < 0.01). The NAA/ (PCr+Cr) ratio decreased significantly at 3 hours after the thrombolysis as compared with that before thrombolysis (0.922±0.16, 1.196±0.01, P < 0.05). In 60-minute self-thrombo-embolism group, the Lac/(PCr+Cr) ratio was higher at 3 hours after thrombolysis than that before thrombolysis (0.846±0.12, 0.601±0.11, P < 0.05) and the NAA/(PCr+Cr) decreased at 3 hours after the embolism. Fluctuation of NAA/ (PCr+Cr) ranged from 0.68 to 0.75 before thrombolysis and from 0.71 to 0.75 at 3 hours after thrombolysis. ② T2W image: T2W image showed that 2 subjects in 30-minute self-thrombo-embolism group whose Lac/NAA was higher than 0.7 suffered from intracranial hemorrhage. This meant that the subjects with Lac/NAA > 0.7 were more likely to suffer from intracranial hemorrhage. ③ Histological and morphological examinations: Optic microscope demonstrated that interspace surrounding nerve cells was widened at ischemic center; neurons were swelling; nucleus was stained lightly; pyknosis and mesenchymal edema were mainly observed in lateral cortex of brow and vertex and in lateral part of corpus striatum.
CONCLUSION: ①Compound parameters in ischemic area before thrombolysis should be regarded as an important predicting marker for thrombolytic therapy, effect evaluation and termination. ② 1H-MRS combining with other imaging technique is a detecting way for screening cases who are suitable for thrombolytic therapy. 相似文献
90.
目的:探讨甲壳素作为骨骼肌组织工程支架材料的可行性。
方法:实验于2002-06/12在南方医科大学应用解剖学研究所完成。大鼠成肌细胞株L6与甲壳素医用缝合线体外复合培养。倒置相差显微镜下观察细胞的形态和排列情况。并分别在体外复合培养的第1,2,3,4,5,6天,取出细胞支架复合体,扫描电镜观察成肌细胞的形态和排列情况。
结果:①扫描电子显微镜观察显示,甲壳素医用可吸收缝线的表面比较粗糙。②倒置相差显微镜下可见大鼠L6细胞与甲壳素制备的医用可吸收缝合线间黏附良好,细胞沿缝线排列呈现串珠样,并可以见到细胞聚集现象。③扫描电子显微镜观察,接种24h后,细胞主要为圆球形,随后细胞迁移、伸展、并见突起;第3天,成肌细胞主要为梭形,并见融合趋势;4d后,细胞沿材料纵轴排列并相互融合,并见肌小管样结构形成及细胞外基质分泌。
结论:甲壳素具有作为支架以构建组织工程化骨骼肌的潜能,支架的平行排列有助于工程化骨骼肌纤维良好方向性的形成。 相似文献