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31.
目的观察Agilent 2100 Bioanalyzer 芯片分析系统(以下简称Bioanalyzer)在基因差异表达研究中的应用。方法应用限制性显示技术分别从正常和热休克处理后的酿酒酵母细胞中分离出cDNA片段,然后再用Bioanalyzer和传统的琼脂糖凝胶电泳技术对RD-PCR产物进行检测分析。结果Bioanalyzer能更快速、敏感地分离和显示差异表达的基因片段,并且通过对差异片段进行定量比较,发现了数个表达有明显差异的基因片段。结论Bioanalyzer在基因差异表达研究中具有重要的应用价值。 相似文献
32.
O. GAROFALO P. G. E. KENNEDY M. SWASH† J. E. MARTIN† P. LUTHERT B. H. ANDERTON P. N. LEIGH 《Neuropathology and applied neurobiology》1991,17(1):39-45
The expression of two heat shock proteins, HSP72 and p57, in addition to ubiquitin, has been studied immunocytochemically in nine amyotrophic lateral sclerosis (ALS) cases and 10 age-matched controls. HSP72 and p57 antibodies did not identify the characteristic ubiquitin-immunoreactive inclusions present in anterior horn cells in ALS spinal cord. Antibodies to HSP72, but not to p57 or ubiquitin, strongly labelled structures corresponding to polyglucosan bodies in spinal grey matter. Such immunoreactive profiles were more abundant in ALS cases, although they were also present in control material. They were sometimes identified by haematoxylin and eosin and periodic acid Schiff reaction, but were not labeled by phosphotungstic acid haematoxylin or by antibodies to glial fibrillary acidic protein. Although ubiquitin, HSP72 and p57 are stress-induced proteins, they are expressed differently and might therefore have different significance in neuronal degeneration. 相似文献
33.
乳酸林格氏液、高渗盐水和全血对失血性休克犬血液动力学的影响 总被引:2,自引:0,他引:2
以失血性休克犬为研究对象,比较乳酸林格氏液(LR)、高渗盐水(HS)和全血(WB)对其血液动力学的影响。经右颈外静脉插入Swan-Ganz飘浮导管,分别在全身氧供(DO2)恢复至休克前水平时,以及液体复苏后5、10、15、30、60和120min时测量动物的各项血液动力学指标。结果显示,HS仅需要11.83ml/kg的液体量,在4.97min时即可使休克犬的DO2恢复至休克前的水平,而LR组和WB组则分别需要52.08ml/kg和23.33ml/kg的液体量,在20.83min和9.33min时才能使休克犬的DO2恢复至休克前的水平。3组动物在DO2恢复至休克前水平时其血液动力学指标均能恢复至休克前的水平。提示高渗盐水比乳酸林格氏液和全血更适合失血性休克患者的早期紧急液体复苏治疗。 相似文献
34.
目的:讨论在院前和急诊科对创伤性休克病人施行早期急救护理,对挽救病人的生命及伤情预后有重要的意义.方法:对我科1997年2月至2001年4月27例创伤性休克病人进行早期,快速,积极的补液,输血增加有效循环量,监测生命体征等综合性抢救治疗与护理措施.结果:经早期积极急救护理,26例病人收缩压维持在60mmHg以上,意识清醒,脉搏有力,转入手术室或专科治疗,1例病人伤势严重抢救无效死亡.结论:创伤性休克病人,伤势复杂,死亡率高,伤后早期院前与急诊科的有效救护,是提高抢救成功率的关键. 相似文献
35.
本文报告39例临床上除外右房肥大的P波高电压,此种P波高电压主要见于冠心病及急性颅脑疾患,二者之和占76.9%。其形态64%与肺性P波相同。产生的机制可能与结间束传导阻滞、中枢调节机能受累、交感神经兴奋性增高等有关。 相似文献
36.
37.
目的探讨内源性热休克蛋白90(HSP90)在缺氧心肌细胞丝氨酸苏氨酸蛋白激酶(AKT)相关信号通路中的作用。方法建立新生Wistar大鼠心肌细胞缺氧模型,将细胞分为正常组、缺氧组、加入HSP90特异性阻断剂格尔德霉素后再缺氧组(格尔德霉素+缺氧组)。于缺氧后1、3、6、12、24、48h用噻唑蓝法检测心肌细胞的活力;缺氧24h,原位缺口末端标记法检测心肌细胞凋亡指数(AI);缺氧1、3、6、12、24h,蛋白质印迹法检测大鼠心肌细胞中内源性HSP90及AKT表达水平。结果(1)缺氧24、48h,缺氧组、格尔德霉素+缺氧组细胞活力均较正常组明显下降(P〈0.05);格尔德霉素+缺氧组细胞活力缺氧12h即开始明显下降,缺氧48h时明显低于缺氧组(P〈0.05)。(2)缺氧24h,缺氧组细胞AI为(10.7±1.2)%,明显高于正常组[(1.9±0.3)%.P〈0.05];格尔德霉素+缺氧组细胞AI为(26、3±5.3)%,明显高于缺氧组(P〈0.01)。(3)缺氧12h,缺氧组心肌细胞内源性HSP90及AKT表达水平高于正常组与格尔德霉素+缺氧组;缺氧24h,缺氧组有所下降.格尔德霉素+缺氧组则下降更明显。结论内源性HSP90对维持心肌细胞的活力有重要作用.缺氧心肌细胞AKT表达水平可受内源性HSP90表达水平的影响。 相似文献
38.
低血容量性休克大鼠心肌细胞Ca2+浓度及膜电位的变化 总被引:1,自引:0,他引:1
目的 旨在探讨低血容量性休克大鼠心肌细胞Ca2 浓度及其膜电位的变化.方法 选用Wistar大鼠84只,随机分成休克高渗复苏组(HES组)、生理盐水复苏组(NS组).建立休克模型,按7个时相(休克前、休克、复苏后5、15、30、60、90min)处死大鼠.取心室肌细胞培养传代,用Fluo-4/AM为游离钙荧光探针、JC-1荧光染色,流式细胞仪分别检测不同时相心肌细胞Ca2 浓度及线粒体膜电位.结果 HES组在休克、复苏后5、15、30min各时间点心肌细胞Ca2 浓度较休克前明显升高,其膜电位较休克前显著降低(P<0.01);在复苏后60、90min心肌细胞Ca2 浓度及线粒体膜电位与休克时比较差异有显著性意义(P<0.01);NS组在休克、复苏后各个时相与休克前比较心肌细胞Ca2 浓度均明显升高,其膜电位明显下降(P<0.01);复苏后各时间点与休克时比较差异无显著性意义(P>0.05);HSE组和NS组在休克后60、90min心肌细胞Ca2 浓度及其膜电位差异有显著性意义(P<0.01).结论 低血容量性休克可诱发大鼠心肌细胞Ca2 浓度升高,线粒体膜电位下降,导致心肌细胞电生理活动障碍;高渗盐溶液不但可改善低血容量休克时心肌细胞Ca2 浓度,而且能有效地稳定其线粒体膜电位;而生理盐水对心肌细胞Ca2 浓度及其膜电位的作用不显著. 相似文献
39.
M. Mizuguchi H. Yamanouchi T. Ichiyama M. Shiomi 《Acta neurologica Scandinavica》2007,115(S186):45-56
Acute encephalopathy is the most serious complication of pediatric viral infections, such as influenza and exanthem subitum. It occurs worldwide, but is most prevalent in East Asia, and every year several hundreds of Japanese children are affected by influenza-associated encephalopathy. Mortality has recently declined, but is still high. Many survivors are left with motor and intellectual disabilities, and some with epilepsy. This article reviews various syndromes of acute encephalopathy by classifying them into three major categories. The first group caused by metabolic derangement consists of various inherited metabolic disorders and the classical Reye syndrome. Salicylate is a risk factor of the latter condition. The second group, characterized by a systemic cytokine storm and vasogenic brain edema, includes Reye-like syndrome, hemorrhagic shock and encephalopathy syndrome, and acute necrotizing encephalopathy. Non-steroidal anti-inflammatory drugs, such as diclofenac sodium and mephenamic acid, may aggravate these syndromes. Severe cases are complicated by multiple organ failure and disseminated intravascular coagulation. Mortality is high, although methylprednisolone pulse therapy may be beneficial in some cases. The third group, characterized by localized edema of the cerebral cortex, has recently been termed acute encephalopathy with febrile convulsive status epilepticus, and includes hemiconvulsion-hemiplegia syndrome and acute infantile encephalopathy predominantly affecting the frontal lobes. Theophylline is a risk factor of these syndromes. The pathogenesis is yet to be clarified, but an increasing body of evidence points to excitotoxicity and delayed neuronal death. 相似文献
40.
Medial epicondylitis is a chronic noninflammatory condition resulting from mechanical injury. Despite many treatment options,
including rest, medications, physiotherapy and operative interventions, the results are too often poor; thus new treatment
options are sought. We treated 4 men with chronic epicondylitis (5 affected joints) with extracorporeal shock wave therapy
after failed attempts of other treatments. The patients’ complaints were graded with the Nirschl scoring system prior to and
six months after therapy. The treatment consisted of three sessions, at 20-day intervals, of 3000 pulses of ultrasonic shock
waves from a Piezolith 3000 unit (energy dosage was gradually increased to reach step 10 equaling 0.9 mJ/mm2). At the 6-month follow-up, no patient was pain free. Three cases had slightly lower Nirschl scores than prior to the procedure
but the patients rated this difference as insignificant; two cases were unchanged. No complications were observed but all
patients rated the procedure as very unpleasant. The well recognized biologic effects of ultrasonographic waves (heat generation,
oscillations, cavitation, etc.) that result in functional and structural changes of cellular membranes with sonochemical reactions
(acceleration of normal metabolism, oxygenation and reduction in water solutions, polymer degradation, etc.), even if present
in our cases, did not result in a noticeable decrease of symptoms, even though we used high energy and more impulses per session.
Significant variations in methodology make inconclusive the results of numerous reports on the use of extracorporeal shock
waves in epicondylar degenerative problems, although ineffectiveness of such therapy is the conclusion of a review by Haake
and colleagues. 相似文献