饲服聚丙烯酰胺动物坐骨神经的超微结构观察

本文对饲服 PAM 的7例大白鼠和饲服 AM 的3例小白鼠坐骨神经内有髓鞘轴突的超薄切片的观察结果如下:(1)神经微丝的数量增加,微丝的直径(11.3nm)接近正常但偏粗。(2)线粒体形态出现多样性变化,以同一线粒体内既有肿胀又有固缩最引人注目。(3)轴突内出现具有界膜的糖原体。(4)髓鞘折皱、板层分离和溶解。(5)光滑膜小泡(SER)数量增加。上述主要超微结构的形态变化,从形态学上支持 AM 中毒机理的“能量代谢障碍说”。     

Inhomogeneous activation of motoneurone pools as revealed by co-contraction of antagonistic human arm muscles

Summary Perceived motion may be a stimulus for anticipatory slow eye movements. To test this possibility, the production of anticipatory slow eye movements in humans was studied using apparent motion stimuli. Short range apparent motion was produced with random dot stimuli and the anticipatory slow eye movements were isolated from the smooth pursuit responses by occasionally including trials in which the random dot stimulus did not appear. Long range apparent motion was produced with subjective contour stimuli. Both short range and long range apparent motion were found to be effective stimuli for anticipatory slow eye movements. The prominence of perceived motion was altered by changing the spatiotemporal displacement intervals in the short range apparent motion stimuli. Changing the subjective contours also changed the motion percepts of the long range apparent motion stimuli. With both stimuli, the peak anticipatory slow eye velocities that were achieved decreased as the prominence of the motion percepts decreased, while the timecourse of the anticipatory responses were similar under the different conditions. These findings indicate that the expectation of perceived motion is necessary for anticipatory slow eye movements.Supported by research grant EY03387 from the National Eye Institute     

利福喷丁和苯巴比妥诱导小鼠肝细胞滑面内质网增生的作用

利福喷丁是新型长效抗结核抗生素,通过透射电镜观察,发现它和典型的肝微粒体酶诱导剂苯巴比妥均能显著诱导小鼠肝细胞滑面内质网的增生。由于这种作用常与肝微粒体酶诱导作用有关,故本文从形态学方面证实了利福喷丁和苯巴比妥对肝微粒体酶具有诱导作用。     

Adenosine triphosphate-activated inward current in isolated smooth muscle cells from rat vas deferens

The electrophysiological effect of adenosine triphosphate (ATP) on the enzymatically dispersed smooth muscle cells from rat vas deferens was investigated. ATP always induced depolarization accompanied with a reduction in membrane resistance. In a whole cell voltage clamp experiment, an inward current was recorded when the cell was exposed to ATP-containing solution. The ATP-induced current disappeared within 2min even in the continuous presence of ATP, which may indicate that the cells were desensitized to this compound. The ATP-induced current was also recorded in the cells superfused with 10^–5M nicardipine or in the Cs-loaded cells, eliminating the possible involvement of voltage-gated Ca and K current. During cell-attached patch clamp, an elementary current having a mean conductance of 20pS was observed when the intrapipette solution was changed to ATP-containing solution. The estimated zero current potentials of the ATP-activated macroscopic current and elementary current were about 0mV. These results suggest that ATP exerts its transmitter-like action by activating ion channels in smooth muscles.     

Apparent dissociation between myosin light chain phosphorylation and maximal velocity of shortening in KCl depolarized swine carotid artery: effect of temperature and KCl concentration

Stimulation of swine carotid artery medial fibers with 110 mM KCl at 37°C results in increases in myosin light chain (MLC) phosphorylation levels and maximal shortening velocity (V _o) during the period of stress development. During the period of stress maintenance, MLC phosphorylation levels andV _o are not maintained, but fall to suprabasal levels, resulting in a correlation between MLC phosphorylation andV _o and suggesting that MLC phosphorylation regulatesV _o. This study identifies other conditions of KCl depolarization of swine carotid medial fibers in which this relationship between MLC phosphorylation andV _o is altered. A decrease in temperature from 37° to 23°C results in a similar magnitude of stress maintenance in response to 110 mM KCl and similar levels of MLC phosphorylation, but a reduction inV _o by approximately 50%. This differential effect of temperature onV _o and MLC phosphorylation results in a downward shift in the slope of the regression line describing the relationship between these two parameters. Decreasing [KCl] to 40 mM in the stimulating solution results again in similar magnitudes of miantained stress. MLC phosphorylation levels are not transient, but maintained at a constant value andV _o is transient at levels approximately 50% of those at 110 mM KCl at 37°C. This results in a complete lack of correlation between MLC phosphorylation andV _o. Thus stress can be developed to equal magnitudes under differing activation conditions with dissimilar patterns of MLC phosphorylation andV _o. Therefore, there is not a strict relationship between MLC phosphorylation andV _o in all cases.     

胃平滑肌肿瘤17例诊治分析

目的 探讨胃平滑肌肿瘤的诊断及治疗。方法 总结11年间收治的胃平滑肌肿瘤17例。结果 平滑肌瘤7例，平滑肌肉瘤10例。主要临床表现为消化道出血、腹部包块和腹痛。内镜、X线钡餐和B超术前检查的阳性率分别为33.3%、46.9%、50.0%，三者联合检查阳性率70.0%。17例中胃楔形或部分切除9例，胃大部切除6例，胃次全切除1例，全胃切除1例。结论 内镜、X线钡餐和B超联合检查可以提高术前诊断率；胃平滑肌瘤首选胃楔形切除或部分切除，胃平滑肌肉瘤首选胃大部切除次全切除。     

同型半胱氨酸对平滑肌细胞增殖的影响及机制

目的 研究同型半胱氨酸(HCY)对平滑肌细胞增殖的影响及机制.方法利用~3H-TdR掺入、血小板衍化生长因子(PDGF)、血管紧张素Ⅱ(AugⅡ)生物活性检测,观察HCY对平滑肌细胞增殖、PDGF和AngⅡ的影响.结果HCY促进平滑肌细胞增殖,同时使平滑肌细胞分泌PDGF、AngⅡ增加,二者均有剂量效应关系.结论HCY促进血管平滑肌细胞增殖,可能是通过促使PDGF、AngⅡ分泌增加实现的.     

十二指肠平滑肌肿瘤的诊断及治疗

目的：探讨十二指肠平滑肌瘤的诊断及治疗方法。方法：回顾性分析1987年至2001年手术切除并经病理证实的7例十二指肠平滑肌肿瘤。结果：十二指肠平滑肌瘤4例、平滑肌肉瘤3例。本病缺乏典型症状，早期诊断困难。本组病人均行手术治疗，取得良好疗效。结论：上消化道出血是本病常见的症状，上消化道造影、胃十二指肠镜及CT扫描是主要的诊断方法。外科手术是首选的治疗方法。     

同型半胱氨酸对体外培养的大鼠动脉平滑肌细胞增殖的影响

目的 :观察同型半胱氨酸 (HCY)对大鼠动脉平滑肌细胞 (ASMCS)增殖的影响。方法 :利用体外细胞培养技术 ,通过 MTT比色测定、细胞计数及流式细胞仪对细胞周期的测定 ,观察同型半胱氨酸对大鼠动脉平滑肌细胞增殖的影响。结果 :同型半胱氨酸能促进大鼠动脉平滑肌细胞的增殖 ,呈明显的剂量依赖关系。药物作用两天后 ,0 .2 m M· L-1HCY组与对照组相比 ,细胞数目增加 4 6 .4 8%,MTT比色OD值增加 4 5 .6 9%(P<0 .0 1) ;经细胞周期的测定 ,结果表明 HCY作用后 G0 ～ G1期细胞数由对照组的 87.2 2 %降低至 76 .6 5 %,减少了 12 .12 %;S期的细胞数由对照组的 0 .0 0 %增加到 6 .6 6 %,处于DNA合成期的细胞数明显增加。结论 :同型半胱氨酸能促进大鼠动脉平滑肌细胞的增殖 ,呈明显的剂量依赖关系。推测 HCY可能通过促进平滑肌细胞的增殖导致动脉粥样硬化的发生。     

干细胞因子对糖尿病小鼠小肠平滑肌细胞慢波的影响

目的:探讨外源性干细胞因子(stem cell factor,SCF)对糖尿病(diabetes mellitus,DM)小鼠小肠动力障碍时小肠平滑肌细胞慢波的影响.方法:♂Balb/c小鼠一次性腹腔注射(ip)链脲佐菌素(STZ,150 mg/kg)造模,将小鼠分为正常组、DM组、DM+外源性SCF组(DM+SCF组);DM+SCF组ip SCF 0.20 μg/(kg·d),正常组和DM组每天ip等量的磷酸盐缓冲液(pH7.40).所有小鼠干预6 wk结束后,给予印度墨水灌胃测定小肠传输速率,用微电极细胞内记录仪记录各组小鼠十二指肠平滑肌细胞内慢波的变化.结果:DM组小肠推进率比正常组的明显降低(44.05%±5.48% vs 82.75%±6.56%,P<0.01);DM+SCF组比DM组的小肠推进率显著增加(75.89%±3.61% vs 44.05%±5.48%,P<0.01).但比正常组的降低(75.89%±3.619% vs 82.75%±6.56%,P<0.05);DM组与正常小鼠相比,十二指肠平滑肌细胞内慢波频率明显减慢(13.33±4.27 vs 30.67±3.33,P<0.01),波幅明显减小(15.17±3.71 vs 35.17±3.71,P<0.01).且波形杂乱不规则.DM+SCF组小鼠十二指肠平滑肌细胞内慢波频率和波幅比DM组增加(26.50±1.87 vs 13.33±4.27;27.50±2.26 vs 15.17±3.71,均P<0.01),但比正常组减慢和降低(26.50±1.87 vs 30.67±3.33,P<0.05;27.50±2.26 vs 35.17±3.71,P<0.01).结论:外源性SCF对DM小鼠的小肠动力障碍有一定的改善作用.