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101.
目的研究凋亡相关蛋白mdm2、bcl-2和AR(雄激素受体)之间的关系,为脑膜瘤的性激素对抗治疗提供一些新信息。方法从华西医院病理科获得04年1月-07年12月病理诊断明确的脑膜瘤共394例,计算机随机抽样60例,其中良性脑膜瘤(WH0I)41例,用LsAB法做免疫组化染色,检测mdm2、bcl-2、AR的表达。结果在良性脑膜瘤中mdm2、bcl-2、AR的表达率分别为67%、62%、33%,三者之间没有相关关系。结论(1)是否能够作为抗性激素治疗疗效的筛选和/或预测指标,bcl-2比mdm2更有潜在价值。(2)AR在脑膜瘤中的促进生长作用的相对独立性,提示AR可以作为脑膜瘤对抗激素治疗的新靶点进一步研究。 相似文献
102.
利用光镜、电镜、免疫组化和形态学定量技术动态研究维生素A对大鼠四氯化碳肝纤维化的抑制作用。结果表明,维生素A可减少四氯化碳中毒大鼠肝内纤维连接蛋白和Ⅰ、Ⅲ型胶原沉积,抑制贮脂细胞向成纤维细胞转化,并可明显地减轻肝纤维化程度。本文还对维生素A抑制肝纤维化的机理及意义作了初步探讨。 相似文献
103.
目的 :观察棘球蚴囊内容物攻击兔所至肺功能和形态的损害。建立囊型包虫肺栓塞的动物模型。方法 :取囊型包虫内容物 ,分离出囊砂 ,与囊液配成 5 %的悬浊液。 2 1只家兔 ,分 3组 :Ⅰ :生理盐水组 ,Ⅱ :澄清囊液组 ,Ⅲ :囊砂悬浊液组。每只家兔都置入股动脉导管及股静脉导管。依照上述分组按 2mL/kg体重分别自静脉导管注射生理盐水、澄清囊液或含囊砂的悬浊液。于注射后 ( 5、30、6 0min)动态监测MAP、血气指标及血清血管活性物质(ET - 1、TXB2 、6 -keto -PGF1α)水平的变化。指标测定后 ,行肺部ECT检查。最后取出动物肺脏行光镜病检。结果 :Ⅲ组和Ⅱ组在注射后均出现MAP、血气指标的明显降低 (P <0 .0 5 )和血清TXB2 、6 -keto -PGF1α的升高 (P <0 .0 5 ) ,尤以Ⅲ组最明显 (P <0 .0 5 )。各组动物血清ET - 1水平在注射前后无明显变化 (P >0 .0 1)。ECT显示Ⅲ组动物肺部放射性缺损 ,Ⅱ组动物肺部放射性减弱。Ⅲ组肺脏病检见头节广泛栓塞于肺小动脉、微小动脉中 ,肺脏呈“急性呼吸窘迫综合症样”改变。Ⅱ组肺组织出现淤血、水肿及炎细胞浸润。结论 :Ⅲ组动物基本能够模拟出囊型包虫病肺栓塞的临床表现。囊液中有形成分在肺损害中起着重要的作用。TXB2 、6 -keto -PGF1α参与了肺损伤病理过程。 相似文献
104.
Sven-Erik Larsson Hongming Cai P. Åke Öberg 《European journal of applied physiology》1993,66(6):483-488
Summary Microcirculation in the upper portion of the trapezius muscle was measured percutaneously by continuous laser-Doppler flowmetry (LDF) during two 10-min series of alternating 1-min periods of static contraction and rest determined electromyographically (EMG). Stepwise increased contraction was induced by keeping the arms straight and elevated at 30, 60, 90 and 135°, which was repeated with a 1-kg load carried in each hand. Thereafter, fatigue and recovery were recorded while the subject kept her arms straight and elevated at 45° carrying the 1-kg hand load as long as possible, followed by rest with arms hanging and no load. A group of 16 healthy women of different ages was studied. Signal processing was done on line using a 386 SX computer. The LDF- and root-mean-square (rms) EMG signals were normalized. Spectrum analyses of EMG mean power frequency (MPF) and median spectrum frequency were performed. The rms-EMG increased significantly with an increase in the calculated shoulder torque (r=0.75). Accumulated local fatigue was indicated by a decrease in MPF with increased shoulder angle and added load (r = –0.54). Blood flow increased with increased shoulder angle (r=0.82, with hand loadr=0.62) and with increased shoulder torque (r=0.72), and also showed a significant increase with increased EMG activity (r=0.74). The LDF showed a negative correlation to MPF (r= –0.67), with increased values when MPF was lowered. During the endurance test, a moderate increase of LDF occurred which reached its maximum during the 1st min of recovery. Then, a slow return to the base level was recorded. The ability to increase the flow in the microcirculation with increasing muscle load was not diminished with age. 相似文献
105.
Acute liver failure was induced in rats by CCl4 administration and its effects on the hepatic Krebs cycle and gluconeogenic fluxes were evaluated in situ by 13C NMR isotopomer analysis of hepatic glucose following infusion of [U-13C]propionate. In fed animals, CCl4 injury caused a significant increase in relative gluconeogenic flux from 0.80+/-0.10 to 1.34 +/-0.24 times the flux through citrate synthase (p<0.01). In 24-h fasted animals, CCl4-injury also significantly increased relative gluconeogenic flux from 1.36+/-0.16 to 1.80+/-0.22 times the flux through citrate synthase (p<0.01). Recycling of PEP via pyruvate and oxaloacetate was extensive under all conditions and was not significantly altered by CCl4 injury. CCl4 injury significantly reduced hepatic glucose output by 26% (42.8+/-7.3 vs 58.1+/-2.4 micromol/kg/min, p=0.005), which was attributed to a 26% decrease in absolute gluconeogenic flux from PEP (85.6+/-14.6 vs 116+/-4.8 micromol/kg/min, p<0.01). These changes were accompanied by a 47% reduction in absolute citrate synthase flux (90.6+/-8.0 to 47.6+/-8.0 micromol/kg/min, p<0.005), indicating that oxidative Krebs cycle flux was more susceptible to CCl4 injury. The reduction in absolute fluxes indicate a significant loss of hepatic metabolic capacity, while the significant increases in relative gluconeogenic fluxes suggest a reorganization of metabolic activity towards preserving hepatic glucose output. 相似文献
106.
肝铸型标本肝静脉吻合的观测及临床意义 总被引:4,自引:0,他引:4
目的:观察肝静脉之间的吻合情况;方法:观察88个铸型标本中肝静脉侧支吻合的出现率,并对一例有丰富吻合支的肝脏用游标卡尺测量吻合中点处的直径;结果:88个肝铸型标本中有侧支吻合22例,显示率25%;1例丰富吻合标本,其中有17处吻合,最大直径为2.28mm,最小直径为0.62mm。副肝静脉与肝静脉吻合3处;结论:在肝静脉结扎或病理变化后,侧支循环开放、增多,受累肝段与未受累肝段间发生浅表和深部肝静脉侧支吻合,使得肝内血管解剖变得异常复杂而完全不同于正常解剖结构,为肝外科手术中处理肝静脉提供了解剖学依据。 相似文献
107.
卵巢切除对四氯化碳诱导大鼠肝纤维化形成的影响 总被引:3,自引:1,他引:3
为探讨卵巢切除对CCl4 诱导大鼠肝纤维化形成的影响 ,采用CCl4 诱导雌性大鼠肝纤维化动物模型 ,观察卵巢切除及雌激素替代治疗 (苯甲酸雌二醇 1mg kg)对肝脏胶原沉积和I、Ⅲ型胶原蛋白表达的影响 ,并分别检测血清学标志及肝脏组织学等变化。结果显示CCl4 模型组大鼠肝脏发生典型的肝纤维化改变 ,卵巢切除组的肝脏胶原沉积更为明显 ,肝脏表达I、Ⅲ型胶原及血清肝纤维化指标也明显高于CCl4 摸型组 (P <0 0 5 ) ,而雌激素干预及替代治疗则可抑制肝纤维化的形成。表明卵巢切除加速CCl4 诱导大鼠肝纤维化的形成 ,其发生可能与卵巢分泌的雌激素对肝纤维化的抑制作用有关。 相似文献
108.
经皮穿刺椎间盘髓核摘除术入路的研究 总被引:1,自引:0,他引:1
为提供椎间盘髓核摘除术形态学依据,在7具成人横断面标本上观察测量了L1~L5椎间盘平面经皮穿刺椎间盘髓核摘除术的进针点、角度和深度。发现在L1~L3、L4~L5椎间盘髓核的穿刺点以距后正中线8~10cm,9~11cm,穿刺角度以46.7°~59.5°,穿刺深度为110.2~128.9mm为最宜。 相似文献
109.
Units which are activated by ascending impulses from the liver within the nucleus of the solitary tract (NTS) were identified by electrical stimulation delivered to the hepatic branch of the vagus. Responses of descending units were eliminated by a collision test. The units which showed decreased firing rates during portal infusion of isotonic glucose solution were also glucose-sensitive so that they showed decreased firing rates during topical application of glucose by means of micro-electro-osmotic techniques. It is concluded that glucose-sensitive neurons exist within the NTS and also that they are functionally linked with hepatoportal glucose-sensitive afferent units. 相似文献
110.