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11.
苏拉明对体外培养视网膜色素上皮细胞增殖的影响   总被引:6,自引:2,他引:6  
目的 研究苏拉明 (suramin)对培养人视网膜色素上皮细胞 (retinal pigm ent epithelium,RPE)增殖的影响 .方法 将不同质量浓度的苏拉明 (1.5 ,15和 15 0 mg· L- 1 )加入RPE细胞培养液 ,采用四甲基偶氮唑盐 (tetrazolium,MTT)比色法 ,细胞分裂指数计数和核仁组成区嗜银染色(Ag NORs)检测苏拉明对 RPE增殖活力的影响 .结果 含有10 0 m L· L- 1小牛血清的培养液可以显著刺激 RPE的增殖(P<0 .0 1) ,无血清组 A值为 0 .19± 0 .0 1、含血清组 A值为0 .30± 0 .0 1;苏拉明抑制了 10 0 m L· L- 1血清条件下 RPE的增殖 ,呈剂量依赖性 ,最大抑制率达 5 1% ,3种浓度组 A值分别为 0 .2 9± 0 .0 1,0 .2 4± 0 .0 1和 0 .14± 0 .0 1,对细胞的形态无明显影响 .结论 苏拉明对血清刺激 RPE增殖有显著非毒性抑制作用  相似文献   
12.
目的回顾性分析治疗P ilon骨折的适宜手术方法、最佳手术时机及其手术疗效。方法对2001年至2004年接受手术治疗的52例单侧P ilon骨折患者进行随访,平均年龄36.5岁,伤后至手术时间平均6.8 d。骨折类型:Ⅰ型4例、Ⅱ型36例、Ⅲ型12例。40例行切开复位三叶型(或T型)钢板内固定;12例行有限切开内固定并辅以外固定,其中应用外固定支架者2例,辅以石膏托者10例。术后平均随访16个月。结果采用Mazur评分系统评估手术疗效,52例患者中,优43例,良6例,可3例。术后并发症包括创面不愈合4例,感染2例,延迟愈合1例和关节退行性变7例。结论正确选择手术时机,根据骨折类型和条件灵活选择固定方式是取得良好手术效果的关键。  相似文献   
13.
BACKGROUNDThree-vessel disease (TVD) with a SYNergy between PCI with TAXus and cardiac surgery (SYNTAX) score of ≥ 23 is one of the most severe types of coronary artery disease. We aimed to take advantage of machine learning to help in decision-making and prognostic evaluation in such patients.METHODSWe analyzed 3786 patients who had TVD with a SYNTAX score of ≥ 23, had no history of previous revascularization, and underwent either coronary artery bypass grafting (CABG) or percutaneous coronary intervention (PCI) after enrollment. The patients were randomly assigned to a training group and testing group. The C4.5 decision tree algorithm was applied in the training group, and all-cause death after a median follow-up of 6.6 years was regarded as the class label.RESULTSThe decision tree algorithm selected age and left ventricular end-diastolic diameter (LVEDD) as splitting features and divided the patients into three subgroups: subgroup 1 (age of ≤ 67 years and LVEDD of ≤ 53 mm), subgroup 2 (age of ≤ 67 years and LVEDD of > 53 mm), and subgroup 3 (age of > 67 years). PCI conferred a patient survival benefit over CABG in subgroup 2. There was no significant difference in the risk of all-cause death between PCI and CABG in subgroup 1 and subgroup 3 in both the training data and testing data. Among the total study population, the multivariable analysis revealed significant differences in the risk of all-cause death among patients in three subgroups.CONCLUSIONSThe combination of age and LVEDD identified by machine learning can contribute to decision-making and risk assessment of death in patients with severe TVD. The present results suggest that PCI is a better choice for young patients with severe TVD characterized by left ventricular dilation.

Coronary artery disease (CAD) is the leading cause of death and disability worldwide.[1] Three-vessel disease (TVD) is the most severe form of CAD and is characterized by significant stenosis in all three major coronary arteries. The application of myocardial revascularization techniques, including coronary artery bypass grafting (CABG) and percutaneous coronary intervention (PCI), has significantly improved the clinical outcomes of patients with severe CAD. CABG has traditionally been the standard therapy for complex coronary lesions, including TVD.[2] In recent years, with the advancements in PCI technology and the accumulation of operators’ experience, the incidence of periprocedural and long-term adverse events of PCI has substantially decreased, and PCI has been gradually applied in the treatment of TVD.[3,4] Current guidelines recommend use of the SYNergy between PCI with TAXus and cardiac surgery (SYNTAX) score and diabetes status to guide the revascularization strategy for patients with TVD.[5,6] Current practice guidelines do not recommend PCI for patients with TVD with a SYNTAX score of ≥ 23. However, using the SYNTAX score to guide clinical decision-making between PCI and CABG remains controversial, and its reasonability has been questioned since a newly published meta-analysis showed no significant association between the SYNTAX score and the comparative effectiveness of PCI and CABG.[7] Moreover, the SYNTAX score is a quantitative indicator of the anatomical complexity of TVD and does not include clinical variables that may have significant effects on the patient’s prognosis. Whether some patients with specific clinical characteristics can obtain a comparable or even greater survival benefit from PCI than from CABG is unclear. Moreover, risk assessment for patients with TVD after revascularization therapy remain challenging.[810]Machine learning has recently emerged as an important research method and has been successfully applied in many scientific fields, including clinical medicine.[1113] The decision tree algorithm, a common approach in machine learning, can handle non-linearity, heterogeneous effects, and high-dimensional features and partition a trial population into subgroups characterized by multiple simultaneous characteristics.[14] In the present study involving a large cohort of patients with TVD with a SYNTAX score of ≥ 23, we employed a decision tree algorithm to generate specific subgroups, compared the long-term prognosis between patients who underwent PCI or CABG in each subgroup, and conducted a comparative analysis of the long-term prognosis between subgroups generated by machine learning. We evaluated whether machine learning can help in selecting the optimal revascularization method and assessing risk in patients with severe TVD.  相似文献   
14.
目的研究碳酸氢钠溶液对人牙釉质抗酸性的影响。方法取制备好的釉质标本40块,随机分成4组,每组10块,设置实验组3组与对照组进行矿化及抗酸实验,分别测定矿化实验及抗酸实验前后各组釉质表面显微硬度值,比较实验前后各组标本显微硬度值的变化。结果矿化实验后,3组实验组釉质标本表面显微硬度值均较实验前显著升高(P〈0.01),对照组硬度值较实验前略有下降,无统计学意义(P〉0.05)。抗酸实验后,实验组和对照组显微硬度值均下降,混合矿化液组下降程度显著高于其他各组(P〈0.01);氟化钠矿化液组与碳酸氢钠矿化液组的下降程度差异无统计学意义(P〉0.05)。结论碳酸氢钠溶液可增加釉质抗酸性,且能协同氟化物增强其抗酸能力。  相似文献   
15.
Background: More widespread use of drug‐eluting stents (DES) to treat coronary heart disease (CHD) has recently generated more attention to thrombosis, which was relative to the polymer. Polymer‐free and biodegradable polymer‐based stents are more frequently studied, but their efficacy on preventing detrimental clinical events is unclear. Methods and Results: To assess whether polymer‐free paclitaxel‐eluting stent (YINYI stent) was noninferior or equivalent to biodegradable polymer‐based rapamycin‐eluting stents (EXCEL stent) in preventing detrimental clinical cardiovascular events, a total of 167 consecutive CHD patients requiring DES implantation were randomly divided into the YINYI group (n = 82) and the EXCEL group (n = 85). The primary end‐point was major adverse cardiac events (MACE). The secondary end‐points included stent thrombosis events, all‐cause mortality, and rehospitalization. The study was designed to test the noninferiority or equivalence of the YINYI stent compared with the EXCEL stent with respect to one‐year MACE according to a noninferiority or equivalence margin of 0.1. One‐year MACE was 6.10% in the YINYI group versus 5.88% in the EXCEL group. The lower limit of the one‐sided 95% confidence interval was ?0.0582 (P = 0.002 from the test for noninferiority). The 95% confidence interval for the equivalence test was [?0.0698, 0.0742] (P1=0.004 and P2=0.007 from 2 times the 1‐sided test for equivalence). There was no statistically significant difference in thrombosis events, all‐cause death, and rehospitalization (all P > 0.05). Conclusions: In this small randomized trial, polymer‐free paclitaxel‐eluting stents appear to be noninferior or equivalent to biodegradable polymer‐based rapamycin‐eluting stents. (J Interven Cardiol 2012;25:604–610)  相似文献   
16.
目的了解青岛市四方区2008-2012年手足口病发病状况及影响因素,制定防治对策。方法采用描述性流行病学分析方法对2008-2012年的手足口病资料进行分析。结果手足口病已成为目前影响儿童健康的主要传染病,2008-2012年青岛市市北区病例数均居甲乙丙类传染病首位;4~9月份为高发季节,7月份达到顶峰;5岁以下儿童为主要发病人群;聚集性发病与卫生环境条件、人群健康知识水平相关;隐性感染者已成为重要的传染源。结论青岛市四方区的手足口病发病趋势与青岛市基本一致,但由于四方区特殊的市区特点,手足口病特别是聚集性病例的发病以外来务工的流动人口为主,提示该人群是今后手足口病防控的重点人群。  相似文献   
17.
采用水数法测定了聚乙二醇单甲醚-聚乳酸两亲嵌段共聚物系列样品的HLB(Hydrophile-Lipophile Balance)值,其数值与分子中亲水基团的体积分数(φEO)呈线性变化规律。以Γ-分布概率密度函数描述聚乳酸链中单个聚乳酸链节对HLB的贡献,则聚乳酸链的有效链长可由Γ-分布概率密度函数的积分求得,由此得到了用基团贡献法估算此类共聚物HLB的方法,HLB计算方法的平均绝对误差小于0.97,与其实验测定误差相当,比常用的Griffin方法更为准确。  相似文献   
18.
目的 探讨芳香化酶抑制剂和三苯氧胺对绝经后Luminal B型乳腺癌患者的疗效.方法 收集天津市肿瘤医院2002年7月至2005年3月间733例术后接受辅助内分泌治疗的原发性乳腺癌患者资料,肿瘤性质均经手术切除病理组织学证实.患者均为绝经后且ER阳性,其中501例接受三苯氧胺治疗,232例接受芳香化酶抑制剂治疗.采用免疫组化SP法进行ER、PR、HER2检测.随访时间36~90个月,中位随访时间46个月.结果 芳香化酶抑制剂治疗组Luminal B型乳腺癌患者三年无瘤生存率高于三苯氧胺组(90.6% vs.88.6%,P=0.038).三苯氧胺组亚组分析显示:LN+/HER2+患者三年无瘤生存率低于LN+/HER2-患者(88.2% vs 90.4%,P=0.037);HER2+/PR+患者高于HER2+/PR-患者(90.8% vs.89.5%,P=0.032).芳香化酶抑制剂组内LN(+)和LN(-)亚组中,HER2(+)患者与HER2(-)患者的三年无瘤生存率差异均无统计学意义(P>0.05);而HER2+/PR+组高于HER2+/PR-组(91.9% vs.90.5%,P=0.029).芳香化酶抑制剂组潮热、阴道出血、静脉血栓形成的发生率低,肌肉骨骼疼痛、骨折的发生率则高于三苯氧胺组(P<0.05).结论 芳香化酶抑制剂对绝经后Luminal B型患者疗效好于三苯氧胺,此效果不受患者腋窝淋巴结状态的影响,且耐受性和安全性较好.  相似文献   
19.
目的 通过热线风速仪观察喉乳头状瘤患儿和普通小儿吸入七氟烷麻醉诱导期呼吸力学的变化,旨在获得预测通气和捕管困难的客观量化指标及对控制通气加深麻醉效果的评估.方法 选择普通患儿(C组)和喉乳头状瘤患儿(L组)各20例,静脉注射氯胺酮1 mg/kg,吸入氧气2 L/min+7%七氟烷实施麻醉诱导.热线风速仪采集四时段呼吸力学数据:静注氯胺酮1 min后(T1),开始吸入7%七氟烷时(T2),吸入7%七氟烷3min后(T3),控制通气2min后(T4).结果 L组T1期呼吸的平均速度[(1.48±0.20)m/s和(1.26±0.18m/s)]、最大速度[(1.72±0.25)m/s和(1.97±0.31)m/s]都高于c组(P<0.05),呼吸频率、吸气时间差异无统计学意义(P>0.05). L组T3、T4期平均吸气速度和最大吸气速度的比值(0.612±0.030和0.613±0.032)小于C组(P<0.05).L组T3期最大吸气速度、呼吸频率下降的幅度[(25±6)%和(19±4)%]少于C组(P<0.05).L组T4期各项指标较T3期无明显变化(P>0.05).结论 喉乳头状瘤患儿吸入七氟烷麻醉诱导期是靠加强呼吸做功来代偿通气不足的,其上气道梗阻情况随麻醉加深更加突出,通过控制通气辅助加深麻醉效果不明显.  相似文献   
20.
目的:在H2O2胁迫下,研究虾青素增强成骨细胞抗自由基损伤的作用。方法:用H2O2作用MC3T3-E1成骨细胞,建立自由基损伤细胞模型。培养的成骨细胞分为对照组、模型组、虾青素低剂量组(1×10^-7mol/L)、虾青素中剂量组(1×10^-6mol/L)和虾青素高剂量组(1×10^-5mol/L)。测定不同处理组细胞活力、超氧化物歧化酶(superoxide dismutase,SOD)活性、活性自由氧(reactive oxygen species,ROS)含量、脂质过氧化物(lipid oxygen,IJP0)含量,同时利用荧光偏振法测定细胞膜流动性。结果:模型组细胞活力、SOD活性、细胞膜流动性均比各剂量虾青素组显著降低(P〈0.01),而ROS、LPO含量均比各剂量虾青素组显著升高(P〈0.01)。结论:H2O2摄入会导致大鼠成骨细胞的氧化损伤,而虾青素可以预防或降低此类损伤对细胞的影响。  相似文献   
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