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131.
Kazumasa Shindo MD Shin-ichi Tsunoda MD Zenji Shiozawa MD 《Clinical autonomic research》1994,4(6):299-302
Microneurography was performed in a 39-year-old woman with demyelination of the pontine white matter associated with muscle spasms in the lower extremities. Single bursts on the microneurogram were observed immediately after cessation of the spasm with no systemic changes in the blood pressure or heart rate. Voluntary tonic flexion of the lower extremities induced similar bursts with small amplitudes. These reflex bursts possessed a characteristic of muscle sympathetic nerve activity, because the latency between the peak of each burst and the prior R-wave on the electrocardiograph was constant. The occurrence of these bursts suggests that a segmental compensatory mechanism in the spinal cord may stabilize the muscle blood flow influenced by muscle contraction. 相似文献
132.
吴在东 《安徽卫生职业技术学院学报》2005,4(2):76-77,75
探索军工研究所发展民品产业之路.本文对军工研究所发展民品产业进行了优劣势分析,继而从机制转换,组织结构,产品战略,市场营销,人才队伍建设等方面提出了一些改革措施. 相似文献
133.
师爱枝 《山西职工医学院学报》2004,14(4):9-10
目的:观察危重型肾功能衰竭合并高危出血患者选择抗凝药物进行血液透析治疗的效果。方法:应用吉派林(低分子肝素钠)作为抗凝剂进行血液透析。结果:129例病人进行血液透析386次,均没有出血发生。结论:吉派林在高危出血患者血液透析中使用方便,安全,效果良好。 相似文献
134.
实施绩效考核的实践和体会 总被引:7,自引:0,他引:7
介绍绍兴市人民医院实施绩效考核的经验和体会.其经验在于:明确考核定位,把考核的首要目的定位于医院管理目标的实现和对管理过程的一种控制;运作方式是:制定考核标准、确立考核周期、明确考核部门及人员,使绩效考核真正落到了实处,收到了显著效果. 相似文献
135.
Meiosis was examined in pollen mother cells of F1 hybrids made from crosses between wheat (Triticum aestivum) and lymegrass (Leymus arenarius and L. mollis). Fluorescence genomic in situ hybridization detected pairing between wheat and lymegrass chromosomes during prophase I and metaphase I. Such pairing, when resulting in bivalent formation, was likely to yield correct disjunction, and hence intergenomic recombination could be incorporated into the gametes. Bivalents in these hybrids, however, were more frequently formed between chromosomes of the same parental origin. Univalents were common, whereas multivalents were not clearly detected. Meiotic behaviour in some cells was not totally aberrant, and this may have accounted for the presence of normal pollen. The results are discussed in relation to intergenomic pairing, meiotic behaviour in wide-hybrids and genome relationships, including the Leymus genome origin. 相似文献
136.
一氧化氮与胚胎异常发育的相关性研究 总被引:3,自引:0,他引:3
为了解开一氧化氮(NO)是否与畸胎发生有关这一谜团和进一步阐明砷致畸作用机理,本实验应用诱生型NO合成酶(iNOS)组织化学、扫描电镜(SEM)及体内致畸试验等方法研究了砷对小鼠卵黄囊胎盘(YSP)和胚胎发育的影响。结果表明YSP细胞iNOS表达与砷浓度之间存在明显的剂量—反应关系(P<0.05);SEM观察可见YSP内皮层和间皮层细胞受损;光镜下可见YSP变小、萎缩和微血管分化不良;随着染毒剂量的升高,畸胎率和死胎率亦逐步增加,最高分别达到56.8%和24.7%;畸胎的主要表现是神经管未闭,心包积液和体位异常等。研究结果率先提示过量NO与畸胎发生及致畸机理关系密切;推荐在致畸研究中iNOS可作为一种有效的生物标志物。 相似文献
137.
目的 探索如何抑制嗜酸细胞的趋化作用,选择β-趋化因子巨噬细胞炎性蛋白4(MIP4)的突变性(Met-MIP4)作为趋化因子受体3的拮抗剂,将Met-MIP4基因在原核细胞中进行表达。方法 设计MIP4基因的PCR引物并进行氨基酸突变,将MIP4N末端的丙氨酸突变为蛋氨酸,以正常人肺酸突变,将MIP4N末端的丙氨酸突变为蛋氨酸。以正常人肺cDNA文库为模板,PCR方法获取Met-MIP4基因,克隆入载体pUC19,测序验证序列已得到突变,将正确的基因插入到GST融合表达载体pGEX-4T中,以IPTG诱导表达。结果 PCR产物为220bp左右的片段,连接入pUC19质粒后测序验证获得正确突变,构建的pGEX-4T融合表达载体在大肠杆菌中表达,经SDS-PAGE凝胶电泳显示有大小约34kU的新生融合蛋白表达。结论 成功突变并克隆了β-趋化因子MIP4基因,SDS-PAGE表明,与GST融合的Met-MIP4突变体已得到表达,为进一步研究其生物学活性奠定了基础。 相似文献
138.
目的 研究电化学人工龋的电化学腐蚀机制。方法 采用循环伏安法研究牙片电极在K2SO4溶液中的氧化还原反应;以失重法并结合SPSS统计软件统计分析,评价牙片在KCl和K2SO4介质中恒电位腐蚀情况,并现场监测电解液氢离子浓度的变化情况。结果 在0.0-2.5V电位范围内,牙片电极与石墨电极具有波形类似的循环伏安曲线;在KCl和K2SO4介质中牙片的腐蚀速度无显著差异;2.0V恒电位腐蚀牙片8h后,阳极池本体溶液pH值由7.0平均下降到3.87,阴极池则由7.0平均升高到10.65。结论 在外电场作用下,牙片的阳极腐蚀与介质无关;水的阳极氧化引起阳极区氢离子浓度升高,致使牙齿发生酸溶是电化学人工龋形成的主要决定因素。 相似文献
139.
Summary— Acidosis affects multiple steps in the excitation-contraction coupling pathway of myocardium, producing decreased calcium sensitivity of myofibrils and modification of the function of the sarcoplasmic reticulum. Our aim was to evaluate the effectiveness of three different classes of inotropic agents under acidotic conditions: 1) forskolin, an adenylate cyclase activator that enhances cellular cyclic AMP concentrations, 2) elevated extracellular Ca2+ and 3) endothelin-1, an activator of the inositol triphosphate, diacylglycerol pathway. Ferret papillary muscles were mounted in organ baths containing normal physiological solution (pH = 7.4). After baseline tension was measured, the muscles were bathed in an acidotic solution (pH = 6.98) that decreased tension to 40% of the control; subsequently, the muscles were washed with normal physiological solution until they returned to baseline. Each inotropic agent was added to the bathing solution in a concentration sufficient to increase tension by 40% above the baseline. Then the solution was made acidotic (pH = 6.98) in the continuous presence of that concentration of inotropic agent and the resultant steady-state developed tension measured. The increases in tension induced by each inotropic agent at normal pH were adjusted to be similar; in contrast, the response to each drug in acidosis was significantly different. Under acidotic conditions, endothelin-1 was the most effective inotropic agent in restoring the depressed developed tension. This was possibly due to enhancement of the myofilament sensitivity to Ca2+ , which was more effective than increasing [Ca2+ ]i through elevating extracellular Ca2+ or the addition of forskolin which increased [Ca2+ ]i but desensitized the myofilaments to Ca2+ . 相似文献
140.
J. Harro Charlotta Löfberg Rein Pähkla Vallo Matto Lembit Rägo Lars Oreland Lembit Allikmets 《Naunyn-Schmiedeberg's archives of pharmacology》1996,355(1):57-63
Cholecystokinin (CCK) is a neuropeptide recently implicated in affective disorders. This study aimed at measuring the levels
of different molecular forms of CCK and the binding characteristics of CCKB receptors in the rat brain after three weeks of treatment with four different antidepressants, imipramine, amitriptyline,
desipramine, and citalopram (all at the dose of 10 mg/kg once per day i.p.). Chronic treatment with imipramine and desipramine
had a significant immobility-reducing effect in the Porsolt‘s swim test. The effect of amitriptyline, albeit in the same direction,
was not significant, and citalopram had no effect in this test. In the elevated plus-maze test of anxiety, all drugs tended
to increase the number of open arm entries and the ratio open/total arm entries, but only the effects of imipramine were statistically
significant. None of the treatments affected the total levels of CCK or the levels of CCK-8-sulphated, CCK-8-nonsulphated,
CCK-5, or CCK-4 in the frontal cortex. There was no effect of the treatments on CCKB receptor binding in the frontal cortex, hippocampus, or striatum. Imipramine and amitriptyline, however, increased the affinity
of CCKB receptor binding in the hypothalamus. Thus, no consistent effect of chronic antidepressant treatment on the CCK-ergic neurotransmission
in the rats was found.
Received: 4 June 1996 / Accepted: 26 August 1996 相似文献