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41.
以小麦(Triticum aestivum L.)品种石4185为材料,研究了45 ℃处理0~120 min对小麦未成熟籽粒谷甘胱肽转移酶(GST)、谷胱甘肽还原酶(GR)、过氧化氢酶(CAT)和过氧化物酶(POD)活性, 超微弱发光,种子萌发和愈伤组织诱导的影响.结果表明,热休克处理使未成熟籽粒萌发率、愈伤组织诱导率和GST活性明显增加,且其作用随处理时间的延长而增大;在处理过程中, CAT活性先减少后增加,热休克对GR活性无明显影响.GST的活性与蛋白质质量分数呈显著正相关.  相似文献   
42.
目的 :探讨七氟醚预适应和缺氧预适应对乳鼠心肌细胞热休克蛋白 70表达的影响。方法 :第 2代培养心肌细胞随机分为正常对照组 (C组 )、缺氧 /复氧组 (A/R组 )、缺氧预适应组 (IP组 )和七氟醚预适应组 (S组 ) ,每组均缺氧 2h ,复氧 48h。分别取复氧 0 ,1,12 ,2 4,36和 48h的细胞 ,用免疫组化染色检测HSP70 表达并进行图象分析。结果 :在各个时间点 ,S组和IP组间的HSP70 表达均显著高于A/R组和C组 (P <0 .0 1) ,A/R组的HSP70 表达略高于C组 ,S组和IP组间的HSP70 表达差异无显著性 (P >0 .0 5 )。随着复氧时间的延长 ,S组和IP组间的HSP70 表达从 1h开始增加 ,2 4h表达最强 ,与 1h相比差异具有显著性 (P <0 .0 5 )。结论 :七氟醚预处理和缺氧预处理均可诱导乳鼠心肌细胞HSP70 在延迟相呈高表达 ,提示HSP70 参与了七氟醚预适应和缺氧预适应的延迟保护相。  相似文献   
43.
目的研究转录因子Egr-1在失血性休克复苏(HS/R)后肝脏损伤中的作用.方法利用Egr-1野生型(WT)和基因封闭型(KO)小鼠复制失血性休克复苏模型.取肝组织,RT-PCR法测定肝组织中TNF-α、IL-6、G-CSF、ICAM-1 mRNA的表达变化.通过检测肝组织中MPO的含量、血清ALT水平和组织学检查,评估肝脏炎症细胞浸润和损伤程度.结果失血性休克2.5 h+复苏4 h后,Egr-1 KO小鼠肝组织中TNF-α、IL-6、G-CSF、ICAM-1 mRNA的表达水平明显低于Egr-1WT组;Egr-1 KO组失血性休克复苏后肝组织炎性浸润和损伤程度减轻,表现为血清ALT水平低,肝组织中MPO含量低,病理损伤轻.结论本实验结果表明转录因子Egr-1参与了失血性休克复苏后肝脏炎症反应基因表达的调节,在失血性休克复苏后的肝脏损伤中起一定的作用.  相似文献   
44.
This study was designed to examine the acute response of normal arterial wall to pulsed laser irradiation. Irradiation with an Excimer or a Holmium YAG laser was performed in 15 normal iliac sites of 8 male New Zealand white rabbits. The excimer laser was operated at 308 nm, 25 Hz, 50 mj/mm2/pulse, and 135 nsec/pulse and the Ho:YAG laser was operated at 2.1 μm, 3.5 Hz, 400 mj/ pulse, 250 μsec/pulse. The excimer and Ho:YAG laser were coupled into a multifiber wire-guided catheter of 1.4 and 1.5 mm diameter, respectively. The mean luminal diameter increased similarly from 2.01 ± 0.29 to 2.46 ± 0.27 mm (P < 0.0005) and from 2.09 ± 0.53 to 2.45 ± 0.30 mm (P < 0.005) after excimer and Ho:YAG laser irradiation, respectively. Perforation occurred in 3 of 15 Ho:YAG irradiated sites and 0 of 15 excimer laser irradiated sites. The sites irradiated with excimer or Ho:YAG laser had similar histologic features, consisting of shedding of the endothelium, disorganization of internal elastic lamina, localized necrosis of vascular smooth muscle cells, and fissures in the medial layer. However, the sites irradiated with excimer laser had lower grading scores than those irradiated with the Ho:YAG laser (P<0.05). Irradiation with excimer or Ho:YAG laser of normal arteries results in: (1) vasodilation of the irradiated artery; (2) localized mechanical vascular injury, and (3) Ho:YAG laser induces more severe damage to the arterial wall than excimer. © 1993 Wiley-Liss, Inc.  相似文献   
45.
Bloodflowvariationandenergymetabolisminthegastricmucosafollowing7.5%hypertonicsalineresuscitationWangJunyi(王俊义);WuGuosheng;(吴...  相似文献   
46.
谈医疗设备漏电对人体的电击   总被引:4,自引:0,他引:4  
医疗设备可以为临床工作提供大量诊断信息和治疗手段,而医疗设备的漏电也会使病人电击灼伤以至危及生命。国务院发布《医疗事故处理条例》以后引起了医疗界高度重视,临床诊疗活动中如何安全使用医疗设备也是预防医疗事故的重要方面。本文着重介绍了电击的种类、对人体的危害及防护措施。  相似文献   
47.
In this study, the behavioural response to dopamine D1-like receptor agonists (SKF 38393, SKF 81297 and SKF 77434) and D2-like receptor agonists (quinpirole and RU 24213), administered alone and in combination to rats treated repeatedly with electroconvulsive shock (five ECS over 10 days) or sham, was tested. Agonist-induced behaviour was monitored by automated activity meters and direct observation using a checklist scoring method. Repeated ECS (compared to sham controls) had no significant effect on the behavioural response to SKF 38393 (7.5 mg/kg SC), SKF 81297 (0.2 mg/kg SC), SKF 77434 (0.1 mg/kg SC), quinpirole (0.1 and 0.25 mg/kg SC) or RU 24213 (0.3 mg/kg SC), when administered alone. In contrast, repeated ECS markedly increased locomotion (activity counts and scores) induced by the non-selective dopamine agonist apomorphine (0.5 mg/kg SC) and by co-administration of a D1-like agonist plus a D2-like agonist [SKF 38393 (7.5 mg/kg SC) plus quinpirole (0.25 mg/kg SC), SKF 81297 (0.2 mg/kg SC) plus quinpirole (0.1 mg/kg SC), and SKF 77434 (0.1 mg/ kg SC) plus RU 24213 (0.3 mg/kg SC)]. This ECS-induced enhancement of dopamine-mediated behaviour was observed for up to 3 weeks after cessation of ECS treatment. In addition, ECS also enhanced the locomotor response to intra-accumbens SKF 38393 plus quinpirole (0.4 and 1.0 μg/side, respectively). These results provide evidence that the enhancement of dopamine function by repeated ECS requires concomitant stimulation of both D1-like and D2-like receptors, and that this effect is long-lasting. Received: 24 January 1997 /Final version: 5 March 1997  相似文献   
48.
Despite numerous publications and clinical trials, the results of treatment of recalcitrant chronic plantar fasciitis with extracorporeal shockwave therapy (ESWT) still remain equivocal as to whether or not this treatment provides relief from the pain associated with this condition. The objective of this study was to determine whether extracorporeal shock wave therapy can safely and effectively relieve the pain associated with chronic plantar fasciitis compared to placebo treatment, as demonstrated by pain with walking in the morning. This was set in a multicenter, randomized, placebo-controlled, double-blind, confirmatory clinical study undertaken in four outpatient orthopedic clinics. The patients, 114 adult subjects with chronic plantar fasciitis, recalcitrant to conservative therapies for at least 6 months, were randomized to two groups. Treatment consisted of approximately 3,800 total shock waves (+/-10) reaching an approximated total energy delivery of 1,300 mJ/mm(2) (ED+) in a single session versus placebo treatment. This study demonstrated a statistically significant difference between treatment groups in the change from baseline to 3 months in the primary efficacy outcome of pain during the first few minutes of walking measured by a visual analog scale. There was also a statistically significant difference between treatments in the number of participants whose changes in Visual Analog Scale scores met the study definition of success at both 6 weeks and 3 months posttreatment; and between treatment groups in the change from baseline to 3 months posttreatment in the Roles and Maudsley Score. The results of this study confirm that ESWT administered with the Dornier Epos Ultra is a safe and effective treatment for recalcitrant plantar fasciitis.  相似文献   
49.
静脉给予纳洛酮2mg/kg期间可使内毒素休克狗的平均动脉压(MAP)、左心室收缩压(LVSP)及其一阶导数(±dp/dt max)和心力环面积(CFU)增加,但对肾血流量(RBF)、尿量及20h的存活率无明显影响。将本实验结果与山莨菪碱、躯体刺激效应进行比较,表明三者中山莨菪碱对休克动物的循环改善作用最明显。  相似文献   
50.
Department of Molecular Pharmacology and Radiobiology, Medico-Biological Faculty, Russian National Medical University, Moscow. (Presented by Academician of the Russian Academy of Medical Sciences P. V. Sergeev.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol, 114, No. 11, pp, 497–500, November, 1992.  相似文献   
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