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81.
目的 探讨临床中术前CT扫描对微创经皮肾镜碎石术后疗效的预测应用价值.方法 采取回顾性方法选取本院2012年1月到2013年12月间的60例微创经皮肾镜碎石术患者的临床资料进行分析,分析手术前CT扫描结石状况,并且依据结石CT值进行分组,观察手术后的效果.结果 <750.0HU组患者穿刺次数为(1.0±0.1)次,≥750.0HU组患者穿刺次数为(2.2±0.2)次,<750.0HU组患者穿刺次数明显的低于≥750.0HU组,差异有统计学意义(P<0.05).<750.0HU组患者结石清除率、术后并发症发生率分别为85.7%、3.6%;≥750.0HU组患者结石清除率、术后并发症发生率分别为62.5%、12.5%;<750.0HU组患者结石清除率高于≥750.0HU组,而<750.0HU组术后并发症发生率明显的低于≥750.0HU组,差异有统计学意义(P<0.05).结论 临床中术前CT扫描对微创经皮肾镜碎石术后疗效的预测,在临床中具有较高的应用价值.  相似文献   
82.
目的:通过体外内皮化和体内内皮化,探讨沉积胶原包埋羟基磷灰石(HA)涂层人工机械瓣膜的可行性及其在人工机械瓣膜支架体内的再细胞化能力。方法制备犬血管内皮细胞(VEC)悬液,接种在胶原包埋 HA 涂层人工机械瓣膜材料上,置培养箱内分组培养如下:①37℃孵箱中静态培养2周;②动态旋转培养装置中培养2周,比较两组 VEC 分泌一氧化氮(NO)、前列环素(PGI2)水平;再分别将人工机械瓣膜植入犬右心房,术后6周,取出部分材料,扫描电子显微镜(SEM)下观察 VEC 在 HA 材料上的附着情况,了解 HA支架材料在体内的再细胞化能力。结果与静态系统相比,人工机械瓣膜在动态旋转系统构建胶原包埋 HA 涂层 VEC分泌 NO 、PGI2水平显著升高(P <0.05);在犬右心房人工机械瓣膜取出材料中,动态旋转系统构建胶原包埋 HA 涂层VEC 层均匀分布,并有心脏内皮细胞附着,而静态培养系统中 VEC 层分布不均匀,胶原包埋 HA 涂层有心脏血管内皮细胞附着,而单纯人工机械瓣薄膜表面出现较多的血栓形成。结论动态旋转系统中构建的组织工程化瓣膜模型中, VEC 可能成为组织工程化机械瓣膜材料;胶原包埋的 HA 涂层人工机械瓣膜有利于 VEC 的黏附和生长。  相似文献   
83.
目的:探讨大黄缓释膜对大鼠牙周炎的治疗作用。方法48只Wistar大鼠,随机分为空白对照组、模型对照组、复方奥硝唑大黄缓释膜组和大黄缓释膜组。各组大鼠均采用左上颌第一磨牙钢丝结扎、注射细菌内毒素并配以高糖饮食的方法建立牙周炎模型。空白对照组大鼠用生理盐水进行处理。各组大鼠造模2h后给予药物进行治疗,第8天处死。检查大鼠龈出血指数、探针深度、牙槽骨吸收。结果与模型对照组比较,给药组大鼠的龈出血指数、探针深度、牙槽骨吸收均降低(P<0.001)。结论大黄缓释膜对实验性牙周炎有明显的治疗作用。  相似文献   
84.
目的探讨单节段脊髓型颈椎病患者颈椎X线片相关指标与椎间盘突出导致的颈脊髓压迫严重程度的相关性。方法回顾性分析2012年8月—2014年3月安徽医科大学第一附属医院脊柱外科诊治的60例单节段脊髓型颈椎病患者的临床资料,均为男性,年龄42~65岁,平均(54.8依9.3)岁。在颈椎MRI矢状位成像上按照颈脊髓受压的比例( E值)分为Ⅰ组、Ⅱ组及Ⅲ组。在颈椎MRI横断面成像上测量并计算颈髓横切面积( S1)与有效椎管横切面积( S0)的比值,以此判断椎间盘突出程度;在不同体位颈椎X线摄片上测量责任椎间隙的活动度值(B值)、椎间隙前缘高度( D值)、颈椎C2~7 Cobb角及椎间孔面积( M值)等相关指标。采用直线相关回归分析颈椎间盘突出程度与各观测指标之间的相关性。结果3组间S1/S0值、E值、B值、D值、C2~7 Cobb角和M值差异均有统计学意义(F值分别为44.187、112.789、7.232、3.778、3.232、15.813,P值均<0.05)。随着S1/S0值的增加,E值、B值、D值、C2~7 Cobb角和M值均逐渐减小,提示责任椎间隙E值、B值、D值、C2~7 Cobb角、M 值与 S1/S0值均呈负相关性( R 值分别为-0.821、-0.581、-0.378、-0.419、-0.576,P值均<0.05)。经多元线性回归分析,B 值、D 值、M 值是 S1/S0的3个独立影响因素, S1/S0值的预测方程为^Y=118.955-1.348X1-2.850X2-0.541X3(复相关系数R=0.742,决定系数R2=0.550,F=22.841,P<0.01),回归模型有统计学意义。结论不同体位颈椎X线摄片的相关指标B值、D值、M值是影响脊髓型颈椎病椎间盘退变突出程度的独立因素,对评估单节段脊髓型颈椎间盘突出的严重程度有一定的诊断价值;采用D值、B值及M值为3个自变量指标,可对椎间盘突出进行预测。  相似文献   
85.
Calcium alginate based controlled release films with moderate mechanical properties were fabricated in this paper. The diffusion mechanism of these films contacting food simulating solvent (FSS) was explored in some detail. With the increase of glycerol content, the diffusion coefficient (D) values of cinnamon essential oils (CEOs) diffusing to ethanol first increased slowly (0.3–0.6 mL), then vigorously (0.6–0.9 mL), and then mildly (0.9–1.2 mL). The D values of the CEOs diffused to water are all in the order of magnitude of 10−10 cm2/s. The D values of CEOs diffused from films EG3 and EGC1 to aqueous ethanol altered enormously at a small moisture percentage (w = 0.3), then continuously varied vigorously, and at last altered mildly in the range of w = 0.3–1. All the results above indicate that, considering the FSS, the diffusion ability of molecules is jointly determined by the size and distribution of free volume in the system (polymer + diffusive substance + solvents), the intermolecular interaction, and the partition coefficient of the solvents. In addition, several pairs of D values, such as DEG and DGA, are very close to each other, indicating that different kinds of interactions between different groups may have the same effect on the diffusion ability of molecules. The correlation between D1 and D2 indicates that polymeric emulsifier chains also exist in the polymer-rich layer. All the findings and analysis could provide the theoretical basis and data support for further molecular dynamic simulation and could guide the design of controlled release food packaging for food protection.  相似文献   
86.
Evidence suggests that asymmetry in frontal electrical activity predicts responses to aversive experiences, such that higher left‐sided activity might dampen responses to trauma reminders. We measured frontal asymmetry at rest and during viewing of a trauma film, and assessed startle responses to film‐reminder images. To explore potential moderators, we compared two films (Study 1; N = 64) and modulated reappraisal (Study 2; N = 72). As expected, left frontal activation during film viewing predicted dampened responses in individuals who viewed a staged road accident. However, this effect tended to be reversed when a genocide documentary was used. In Study 2, all participants viewed the genocide film. Left frontal activity at rest again predicted higher startle responses, while reappraisal did not moderate the effects. Thus, the type of trauma film plays a crucial role in the effects of frontal asymmetry, which warrants further critical investigation.  相似文献   
87.
利用C8051 F340单片机以及无线控制技术实现对高频X射线机主控平台以及无线控制系统的设计与开发,为临床医生提供良好的人机交互方式,操作界面简单,能在多环境、多疾病、多操作的情况下可以进行远距离曝光操作。  相似文献   
88.
A fused aromatic furan‐substituted diketopyrrolopyrrole and novel diphenylfumaronitrile conjugated building blocks are used for the synthesis of an alternating copolymer ( DPFN‐DPPF ) via Suzuki polycondensation. In this paper, the first attempt to use the diphenylfumaro­nitrile building block for the synthesis of conjugated polymer is described. The number‐average and weight‐average ­molecular weights calculated for DPFN‐DPPF are 20 661 and 66 346 g mol?1, respectively. The optical bandgap calculated for DPFN‐DPPF is 1.53 eV whereas the highest occupied molecular orbital (HOMO) value calculated by photoelectron spectroscopy in air (PESA) is 5.50 eV. The calculated HOMO value is lower, which is suitable for stable organic electronic devices. DPFN‐DPPF polymer is used as an active layer in bottom‐contact bottom‐gate organic thin‐film transistor devices and the thin film exhibits a hole mobility of 0.20 cm2 V?1 s?1 in air.

  相似文献   

89.
Al2O3 films were prepared by the aerosol deposition method at room temperature using different carrier gas compositions. The layers were deposited on alumina substrates and the film stress of the layer was calculated by measuring the deformation of the substrate. It was shown that the film stress can be halved by using oxygen instead of nitrogen or helium as the carrier gas. The substrates were annealed at different temperature steps to gain information about the temperature dependence of the reduction of the implemented stress. Total relaxation of the stress can already be achieved at 300 °C. The XRD pattern shows crystallite growth and reduction of microstrain while annealing.  相似文献   
90.
Nanostructured diamond (NSD) films were grown on silicon and Ti–6Al–4V alloy substrates by microwave plasma chemical vapor deposition (MPCVD). NSD Growth rates of 5 μm/h on silicon, and 4 μm/h on Ti–6Al–4V were achieved. In a chemistry of H2/CH4/N2, varying ratios of CH4/H2 and N2/CH4 were employed in this research and their effect on the resulting diamond films were studied by X-ray photoelectron spectroscopy, Raman spectroscopy, scanning electron microscopy, and atomic force microscopy. As a result of modifying the stock cooling stage of CVD system, we were able to utilize plasma with high power densities in our NSD growth experiments, enabling us to achieve high growth rates. Substrate temperature and N2/CH4 ratio have been found to be key factors in determining the diamond film quality. NSD films grown as part of this study were shown to contain 85% to 90% sp3 bonded carbon.  相似文献   
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