49 research outputs found
双蒲散对慢性萎缩性胃炎大鼠胃黏膜细胞TGF-β1/Smad3信号通路的影响
目的 :观察双蒲散对慢性萎缩性胃炎的治疗作用以及胃黏膜细胞TGF/Smad信号通路的影响。方法 :40只SD大鼠随机分为正常组、模型组、双蒲散组和维酶素组,每组10只。采用N-甲基-N`-硝基-N-亚硝基胍(MNNG)方法复制慢性萎缩性胃炎大鼠模型,正常组不处理,模型组只造模不干预,其余两组造模16周后分别灌胃双蒲散和维酶素4周。光镜观察胃黏膜组织病理学,酶联免疫吸附法测定胃黏膜组织Bcl-2、P53、PCNA、Ag-NORs、EGF、TGF-β1与Smad3蛋白的表达。结果 :与正常组比较,模型组大鼠胃黏膜组织Bcl-2、P53、PCNA、Ag-NORs、EGF、TGF-β1的表达皆明显升高,Smad3皆显著下降(P<0.05);与模型组比较,双蒲散组大鼠胃黏膜组织Bcl-2、P53、PCNA、Ag-NORs、EGF、TGF-β1的表达皆明显下降,Smad3皆显著升高(P<0.05),其效应显著高于维酶素组。结论 :双蒲散可通过调节TGF-β1/Smad3信号通路调节慢性萎缩性胃炎大鼠胃黏膜细胞的增殖和凋亡,抑制胃黏膜细胞的异型增生,阻断慢性萎缩性胃炎向胃癌前病变发展。国家自然科学基金项目(81260556);; 江西省自然科学基金项目(20131512040019
INFLUENCE OF SURFACE ROUGHNESS ORIENTATIONS ON FRICTION COEFFICIENT OF WHEEL/RAIL SPECIMEN IN OIL LUBRICATION
黏着力是列车安全与平稳运行的关键因素之一.最大黏着力与摩擦力有关,摩擦力的减小会导致黏着力的降低.表面粗糙度及其取向是影响摩擦系数的重要因素,然而,有关表面粗糙度取向对于混合润滑状态下摩擦系数的影响的研究结论似乎是矛盾的.用激光离散改性技术将车轮试样表面制备成具有菱形、纵纹、横纹3种典型的形貌,并且与不作激光离散改性处理的车轮试样作对比,用基于确定性模型的统一雷诺方程数值分析法和小比例尺度的轮轨试样摩擦学实验,得到的结论是:在油润滑状态下,激光表面形貌大幅提高摩擦系数,其中菱形对应的摩擦系数最大,纵纹与横纹的摩擦系数相差不大,摩擦系数的大小主要取决于由表面粗糙度取向决定的接触区内粗糙峰接触压力与总压力之比,侧流效应也是影响摩擦系数的重要因素,它主要取决于接触区内表面粗糙度的取向
Effects of Moxibustion on Gastric Stress Ulcer Rats' Apoptosis Protein Phosphorylation
目的:研究艾灸对应激性胃溃疡大鼠胃黏膜细胞凋亡蛋白质磷酸化的影响,探讨艾灸促进胃黏膜损伤修复的信号转导机制。方法:将大鼠随机分为正常组、模型组、胃经穴组和对照点组,采用束缚冷应激法制作应激性胃溃疡大鼠模型,肉眼观察大鼠胃黏膜损伤程度,APOPTOSIS MICrOArrAy SlIdES芯片检测胃黏膜细胞凋亡蛋白质磷酸化水平。结果:与模型组比较,胃经穴组和对照点组大鼠胃黏膜损伤指数值均显著降低(P<0.05);与对照点组比较,胃经穴组大鼠胃黏膜损伤指数显著降低(P<0.05);APOPTOSIS MICrOArrAy SlIdES芯片检测结果显示:与模型组比较,胃经穴组大鼠胃黏膜细胞10种蛋白质磷酸化水平上调,其中bCl-Xl、MCl-1、bCl-2、IAPS 4种蛋白磷酸化水平差异有统计学意义(P<0.01,P<0.05);18种蛋白质磷酸化水平下调,其中Tnf、fAS、APAf-1、CASPASE-3、CASPASE-9、bAX 6种蛋白质磷酸化水平差异有统计学意义(P<0.01,P<0.05)。结论:艾灸可促进胃黏膜的损伤修复,调节多种凋亡相关信号蛋白质的磷酸化水平,并且存在一定的经脉脏腑相关性。Objective: To study the effects of moxibustion on apoptosis protein phosphorylation in rats with gastric stress ulcer and to explore the signal transduction mechanisms promoting gastric mucosal injury and repairing moxibustion.Methods: The rats were randomly divided into normal group,model group,stomach meridian group and the control point groups and each group had 10 rats.The stress ulcer rat model was established by using restraint cold stress method.We observed the rat gastric mucosa injury degree and Apoptosis Microarray Slides microarray was used to observe the gastric apoptosis protein phosphorylation levels.Results: Compared with the model group,the gastric mucosa injury index values of control point and meridian groups were significantly lower( P < 0.05).Compared with the control point group,a significant reduction in rat gastric mucosa injury index was in meridian group( P < 0.05).Apoptosis Microarray Slides microarray results showed that 10 kinds of protein phosphorylation levels increased,among which Bcl- XL,Mcl- 1,Bcl-2 and IAPs protein phosphorylation levels were statistically significant( P < 0.01,P < 0.05) and 18 kinds of protein phosphorylation levels decreased,among which TNF,Fas,Apaf- 1,Caspase- 3,Caspase- 9 and Bax protein phosphorylation levels were statistically significant( P < 0.01,P < 0.05).Conclusion: Moxibustion can promote gastric mucosal injury and repair and regulate phosphorylation of several proteins related to apoptotic signals and there is a certain correlation between the meridians organs.国家自然科学基金项目(30960484;81260556
舒芬太尼复合异丙酚抑制气管插管应激反应的效果
【目的】比较靶控输注不同剂量舒芬太尼复合异丙酚抑制气管插管应激反应的效果。【方法】60例择期上腹部手术患者,ASAⅠ~Ⅱ级,随机分为3组m=20),全麻诱导时,A组、B组、C组分别靶控输注效应室浓度为0.3、0.5、0.7ng/mL的舒芬太尼2min后.均输注效应室靶浓度为4μg/mL的异丙酚,病人意识消失后给予维库溴铵行气管插管。记录全麻诱导前1min(T1)、气管插管后1min(T2)、3min(T3、10min(T4)各时点平均动脉压(MAP)、心率(HR);并于T1、T2、T4时点采集桡动脉血,测定血浆肾上腺素(AD)和去甲肾上腺素(NA)浓度。【结果】(1)A组T2时点MAP、HR比T。时点明显升高(P〈0.0S),C组T2、T3、T4时点MAP明显低于A组(P〈0.05),C组T2、T3时点HR明显低于A组(P〈0.05),C组L、T4时点MAP低于B组(P〈0.05);(2)A组T2时点血浆AD和NA浓度较T1时点明显升高(P〈0.05)、较B组高(P〈0.05)、较C组高(P〈0.05)。【结论】靶控输注舒芬太尼复合异丙酚可以有效抑制气管插管应激反应,其中舒芬太尼效应室浓度0.5ng/mL复合异丙酚效应室浓度4μg/mL靶控输注的效果较好
Effect of Laser Textured Surface on Adhesion Coefficient of High-speed Wheel/Rail Contact under Water/Ice Lubrication
轮轨黏着特性是影响列车牵引和制动的重要因素,轮轨黏着特性的研究对于列车安全平稳运行、减少轮轨疲劳和表面擦伤,以及降低脱轨风险都具有重要意义。轮轨之间的黏着特性主要体现在黏着系数上,影响黏着系数的因素很多,例如蠕滑率、速度、润滑介质特性、轮轨表面粗糙度和表面形貌取向等。
本文主要研究激光毛化形成的车轮表面形貌取向对水润滑和冰润滑条件下运行的高速列车轮轨黏着特性的影响。根据弹流润滑理论,对于水作为润滑介质的情况,将轮轨接触按混合润滑情况处理,基于统一Reynolds方程方法计算了车轮表面具有纵纹、横纹、菱形三种形貌以及无激光毛化处理的随机形貌的黏着系数随蠕滑率、速度而变化的规律;对于零摄氏度以下,冰作为润滑介质的情况,首先计算了具有随机形貌的轮轨接触区压力分布,根据冰的相图和压力融化原理,将接触区分为混合润滑区域和固体(冰-钢)接触区域,在混合润滑区仍然用统一Reynolds方程进行计算,而在冰-钢接触区域,用退化的Reynolds方程,即Hertz方程进行计算,总的黏着系数是两个区域黏着系数之和。最后,计算了蠕滑率为0.02条件下纵纹、横纹、菱形三种激光毛化形貌车轮表面在0~-21℃温度范围内的黏着系数。
本文主要结论是:
(1)在水润滑条件下,激光毛化形貌有明显的增粘效果,其中,菱形分布增粘效果最明显,横纹优于纵纹;
(2)对无量纲压力和膜厚的计算显示,载荷比是影响黏着特性的主要因素,载荷比表示固体承担载荷的比例,激光毛化技术可以有效提高载荷比;
(3)冰润滑时,在相同的蠕滑率和速度条件下,黏着系数比水润滑情况更低,随着温度升高,冰润滑的黏着系数逐渐增加;
(4)激光毛化形貌在冰润滑的条件下也有显著的增粘效果。
关键词:高速列车,黏着系数,形貌取向,混合润滑
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资源约束项目计划资源转移成本优化方法
资源约束项目计划因更接近管理实际而得到广泛应用,但目前的研究未将活动间的资源转移成本纳入优化范围内。实际上,不同资源分配方案产生的资源转移成本差别会很大。在严格区分并清楚定义前、后项活动基础上,考虑资源转移成本的资源约束项目计划模型能优化资源转移总成本,并且求解算法明确、步骤少
MOCVD生长Al_(0.48)Gao_(0.52)N/Al_(0.54)Ga_(0.36)N多量子阱的结构和光学特性
采用金属有机物化学气相淀积(MOCVD)技术,在蓝宝石衬底上生长了Al_(0.48)Gao_(0.52)N/Al_(0.54)Ga_(0.36)N多量子阱(MQWs)结构.通过双晶X射线衍射(DCXRD)、原子力显微镜(AFM)和阴极荧光(CL)等测试技术,分别对样品的结构和光学特性进行了表征.在DCXRD图谱中,可以观察到明显的MQWs衍射卫星峰,通过拟和,MQWs结构中阱和垒的厚度分别为2.1和9.4 nm,Al组分分别为0.48和0.54.在AFM表面形貌图上,可以观察到清晰的台阶流,表明MQWs获得了二维生长;与此同时,MQWs结构存在一些裂缝,主要原因为AlGaNMQWs结构和下层GaN层间存在很大的应力.CL测试表明,AlGaN MQWs结构的发光波长为295 nm,处于深紫外波段,同时观察到处于蓝光、绿光波段的缺陷发光
Research on the Effect of Moxibustion on Gastric Mucosal Injury Repair Related Cell Signaling Proteins with Protein Fingerprinting
目的研究艾灸对胃黏膜损伤修复相关细胞信号蛋白质的影响,探讨艾灸促进胃黏膜损伤修复的分子机制。方法40只Sd大鼠随机分为正常组、模型组、胃经穴组和对照点组各10只,采用束缚冷应激法建立应激性胃溃疡大鼠模型,胃经穴组大鼠造模后鼠板束缚,艾灸胃经“梁门“、“足三里“穴位;对照点组鼠板束缚,艾灸对照点;空白组和模型组仅鼠板束缚,各组均每次20MIn,每日1次,持续12天。应用蛋白质指纹图谱技术和疏水芯片、亲水芯片、金属离子螯合芯片检测各组大鼠胃黏膜细胞蛋白质指纹图谱,对比分析各组的差异蛋白质质荷比峰。结果各组蛋白质指纹图谱比较,3个芯片共检测出10个标志蛋白质差异表达,其中疏水芯片有3个标志蛋白质表达差异,分子量分别是2736dA、6985dA、7324dA;亲水芯片有1个标志蛋白质表达差异,分子量是4561dA;金属离子螯合芯片有6个标志蛋白质表达差异,分子量分别是1034dA、2136dA、3261dA、4871dA、7586dA、8267dA。结论艾灸可调节胃黏膜损伤模型大鼠多种相关信号蛋白质的差异表达,这可能是其促进胃黏膜损伤修复的分子机制之一。Objective To study the effect of moxibustion on gastric mucosal injury repair related cell signaling proteins and its molecular mechanism.Methods Forty SD rats were randomized into the normal(blank)group,model group,stomach channel point group and control point group,with 10in each.The stress ulcer rat models were established with restraint cold stress method.The stomach channel point group was given moxibustion on Liangmen(ST21)and Zusanli(ST36).The control point group was given moxibustion on the control points.The rats in the blank and model groups were tied with mouse board only.Each group was given corresponding measures 20min each time and once daily for 12days.The mucosal cell protein fingerprint was detected with protein fingerprinting,hydrophobic chip,hydrophilic chip and metal ion chelating chip.The mass-to-charge ratio of differential protein in each group was compared and analyzed.Results Comparison of protein fingerprints in each group showed that 10signs of differentially expressed proteins were detected in 3chips.Three signs of differentially expressed proteins were detected in hydrophobic chip and their molecular weights were 2736Da,6985Da and7324Da.One sign of differentially expressed protein was detected in hydrophilic chip and its molecular weight was 4561Da.Six signs of differentially expressed proteins were detected in metal ion chelating chip and their molecular weights were 1034Da,2136Da,3261Da,4871Da,7586Da and 8267Da.Conclusion Moxibustion can regulate the differential expression in a variety of related signaling proteins and promote the repairation of gastric mucosal injury.国家自然科学基金资助项目(30960484;81260556); 江西省自然(青年)科学基金资助项目(2008GZY0022); 江西省教育厅2009年度科技计划资助项目(GJJ09280