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1.
目的 观察双乳突法低频电刺激对大鼠局灶性脑缺血再灌注损伤的保护作用,并探讨其作用机制。方法 用线栓法制备一侧大脑中动脉栓塞-再灌注(MCA-OR)大鼠模型,造成右脑缺血2h再灌注24h,采用5级评分法评定神经功能缺损来筛选病例。脑含水量用干重湿重法测定,用TTC染色-图像分析仪测定梗死灶体积,并分析缺血侧脑组织超氧化物歧化酶(SOD)和丙二醛(MDA)含量的变化。结果 与对照组相比,治疗组大鼠(即刻治疗组除外)脑水肿程度明显减轻(P〈0.05),脑梗死体积减小(P〈0.05),脑组织中SOD含量增加,而MDA值下降(P〈0.05)。结论 双乳突法低频电刺激对脑缺血再灌注损伤具有神经保护作用,此作用可能与减轻脑水肿、提高SOD活性、降低MDA含量及缩小梗死体积有关。  相似文献   

2.
纳洛酮对大鼠局灶性脑缺血再灌注损伤后脑组织NO的影响   总被引:1,自引:0,他引:1  
目的:探讨纳洛酮对局灶性脑缺血再灌注损伤的保护作用。方法:56只Wistar大鼠随机分为7组。采用腔内线栓法制备动物模型,检测纳洛酮治疗组及对照组大鼠脑组织NO含量、脑组织含水量及梗死体积。结果:大鼠脑缺血再灌注后脑组织NO含量显著升高,应用纳洛酮后缺血侧脑组织NO含量下降,脑组织水肿减轻,梗死灶体积显著减小。结论:纳洛酮可以减轻脑缺血再灌注损伤,其机制可能与纳洛酮降低急性缺血脑组织N0含量有关,纳洛酮具有神经保护作用。  相似文献   

3.
目的观察还原型谷胱甘肽对大鼠短暂性局灶性脑缺血时丙二醛(MDA)、谷胱甘肽过氧化物酶(GSH-PX)、超氧化物歧化酶(SOD)的影响。方法采用大脑中动脉线栓法制备大鼠局灶性脑缺血模型,随机分为假手术组、缺血模型组和还原型谷胱甘肽治疗组(1200mg/kg),缺血2h再灌注6h后观测各组的神经行为变化,脑梗死体积,脑组织病理学变化,脑组织MDA含量和SOD、GSH—PX活性。结果还原型谷胱甘肽可以改善大鼠局灶性脑缺血引起的神经行为障碍,减少脑梗死体积(P〈0.05);可以降低脑组织MDA含量,提高脑组织GSH—PX、SOD活力(P〈0.05)。结论外源性谷胱甘肽可通过提高GSH—PX、SOD活力,降低MDA含量,增强机体清除自由基的能力,及减少大鼠脑组织氧自由基的堆积而发挥对脑缺血再灌注时的保护作用。  相似文献   

4.
目的探讨电刺激小脑顶核(FNS)对成年大鼠局灶脑缺血/再灌注后脑内不同部位、不同时间点Nestin表达的影响。方法采用线栓法制备大鼠右侧大脑中动脉局灶脑缺血/再灌注模型。180只雄性Wistar大鼠随机分为正常对照组(NC组)、假手术组(SC组)、局灶脑缺血/再灌注组(I/R组)、局灶脑缺血/再灌注+假FNS组(I/RFs组)、局灶脑缺血/再灌注+FNS组(I/RF组),每组36只,并根据再灌注时间的不同又分为1d、3d、7d、14d、21d和28d6个亚组(n=6)。缺血时间均为1h,于再灌注后立即刺激对侧小脑顶核1h。应用免疫组织化学技术检测缺血侧侧脑室、海马Nestin阳性细胞的动态表达。结果局灶脑缺血/再灌注后不同时间点Nestin阳性细胞在缺血侧侧脑室区、海马齿状回的表达均有增加,呈单峰变化趋势,7d达高峰(P〈0.01),14d后逐步下降(P〈0.01),而FNS后,Nestin阳性细胞数量增加更加明显(P〈0.05,P〈0.01),7d达到高峰(P〈0.01),14d后仍维持在较高水平(P〈0.01),且Nestin阳性细胞形态也发生明显变化。结论FNS可促进局灶脑缺血/再灌注后脑内Nestin阳性细胞数量增加。  相似文献   

5.
目的通过观测小剂量超短波(USW)对大鼠脑缺血再灌注后脑梗死体积,脑组织中B细胞淋巴细胞瘤-xl(Bcl-xl)及肿瘤坏死因子-α(TNF-α)表达的影响,进一步探讨小剂量USW对脑缺血再灌注损伤保护作用的机制。方法用线栓法制备一侧大脑中动脉栓塞再灌注大鼠模型,造成大鼠右脑缺血2h再灌注24h,采用Longa5级评分法评定神经功能缺损程度。大鼠按体重随机分成空白对照组、对照组及超短波治疗组(USW组),后2组选择Longa5级评分法为2分的大鼠。所选大鼠均于再灌注24h后断头取脑,分别测定脑梗死灶体积、脑组织中Bcl-xl及TNF-α的表达。结果与对照组比较,USW组梗死体积及梗死体积占全脑体积的百分比均降低,差异具有统计学意义(P〈0.05)。与对照组比较,USW组脑组织中Bcl-xl表达增加,TNF-α水平降低,差异均具有统计学意义(P〈0.05)。结论小剂量超短波可通过增加Bcl-xl表达,降低TNF-α水平而抑制脑神经细胞凋亡,挽救半暗带,缩小脑梗死灶,减小梗死体积,从而保护脑缺血再灌注后损伤神经,进而提高治疗效果。  相似文献   

6.
目的:探讨神经生长因子(NGF)对大鼠脑缺血再灌注损伤的保护作用及其机制。方法:采用大脑中动脉内栓线阻断法(MCAO)造成大鼠局灶性损伤模型,同时给予NGF治疗。观测神经评分改变,计算脑组织梗死灶,测定脑组织含水量以及一氧化氮合酶(NOS)活动的变化。结果:NGF治疗组神经评分明显降低(P〈0.05);与脑缺血再灌注组比较,NGF治疗组脑缺血梗死区缩小,脑组织含水量和NOS活性明显降低(P〈0.05)。结论:NGF具有保护脑缺血再灌注损伤的作用,可能与抑制NOS的活性有关。  相似文献   

7.
目的:探讨尼莫地平与甘露醇联合治疗局灶性脑缺血再灌注大鼠的神经保护作用。方法:采用线栓法制备大鼠大脑中动脉缺血2h再灌注24h模型并术前15min分别静脉注射生理盐水、20%甘露醇、尼莫地平以及20%甘露醇和尼莫地平,通过TTC、TUNEL染色分别观察梗死灶体积和凋亡细胞数目的改变。结果:甘露醇与尼莫地平联合治疗组梗死灶体积显著缩小、凋亡细胞数目显著降低(P<0.05)。结论:尼莫地平与甘露醇联合治疗可通过抗细胞凋亡机制发挥对局灶性脑缺血再灌注大鼠的神经保护作用。  相似文献   

8.
目的 观察Wistar大鼠局灶脑缺血/再灌注后,脑内核因子—κB(NF—κB)活性及其活化的基本规律,并探讨电刺激小脑顶核(FNS)对其影响。方法成年雄性Wistar大鼠27只,随机分为正常组、单纯局灶脑缺血/再灌注组(模型组)和局灶脑缺血/再灌注+电刺激小脑顶核治疗组(FNS治疗组)。采用线栓法制备右侧大脑中动脉闭塞(MCAO)模型,缺血时间均为2h,根据再灌注时间分为缺血2h/再灌注3,6,12和24h组?模型组不给予任何干预处理,FNS治疗组在缺血2h再灌注即刻给予FNS治疗1h。用Westernblot法检测缺血脑组织核抽提物中NF—κBp65蛋白的表达,用电泳迁移率改变分析法(EMSA)检测核抽提物中NF—κBDNA的结合活性=结果正常组大鼠脑组织核抽提物中有少量NF—κBp65蛋白,NF—κBDNA结合活性较弱。模型组再灌注各时间点,即再灌注3,6,12和24h,NF—κBp65蛋白含量均高于正常组,其中再灌注6h和12h均显著高于正常组(P〈0.05)。模型组NF—κBp65蛋白含量变化趋势为:再灌注3h〈再灌注6h〈再灌注12h,再灌注12h达峰值,各组间差异具有统计学意义(P〈0.05);再灌注24h时NF—κBp65蛋白含量明显低于再灌注6h和12h(P〈0.05)。模型组NF—κBDNA结合活性除再灌注3h外,其余3个时间点均显著高于正常组(P〈0.05);模型组再灌注3h时,NF—κBDNA结合活性明显弱于组内其余3个时间点(P〈0.05),这3个时间点均为高活性状态,组内差异无统计学意义(P〉0.05)。FNS治疗组NF—κBp65蛋白含量及NF—κBDNA结合活性的变化趋势与模型组相似。其中,再灌注6h和12h时,FNS治疗组NF—κBp65蛋白含量明显低于模型组相应时间点(P〈0.05);再灌注6,12和24h时,FNS治疗组NF—κBDNA结合活性也明显低于模型组相应时间点(P〈0.05)。结论大鼠局灶脑缺血/再灌注后缺血脑组织中NF—κB活化明显,活性增强;FNS可下调NF—κB活化程度,抑制NF—κBDNA结合活性,这可能是FNS具有“抗炎”作用的重要机理之一。  相似文献   

9.
目的探讨绞股蓝总皂苷(Gypenosides,GP)对大鼠脑缺血再灌注损伤的保护作用及其机制。方法采用线栓法建立大鼠脑缺血再灌注损伤模型,实验分为假手术组、模型组、血塞通阳性药组(20mg·kg^-1)、绞股蓝总皂苷高、中、低剂量组(100、30和10mg·kg^-1),观察绞股蓝总皂苷对脑缺血再灌注大鼠神经功能评分、脑组织匀浆中SOD、MDA、NO含量等生化指标及梗死面积变化的影响,同时观察HE病理改变,用免疫组化方法观察绞股蓝总皂苷对Bcl-2、Bax蛋白表达的影响。结果与模型组比较绞股蓝总皂苷可改善大鼠神经功能评分(P〈0.05),提高大鼠脑组织中s0D活性(P〈0.05),降低其MDA含量(P〈O.05),缩小脑梗死面积(P〈0.05)。免疫组化结果显示绞股蓝总皂苷可明显提高Bcl-2呈阳性的细胞数(P〈0.05),降低Bax阳性的细胞数(P〈0.05)。结论绞股蓝总皂苷能够改善大鼠脑缺血再灌注损伤,可通过保护脑组织抗氧化酶的活性,抑制脂质过氧化反应,减轻自由基对脑组织的损害,对缺血再灌注脑组织具有治疗作用。  相似文献   

10.
目的探讨缺血后适应与缺血预适应对大鼠脑缺血再灌注损伤的影响。 方法用大脑中动脉线栓法制作大鼠局灶性脑缺血再灌注损伤模型。30只SD大鼠分为脑缺血再灌注模型组(模型组)、缺血后适应组及缺血预适应组,每组10只。以脑梗死体积、神经功能缺陷评分、超氧化物歧化酶(SOD)活性和丙二醛(MDA)含量评价缺血预适应与缺血后适应抗脑缺血再灌注损伤的作用。 结果缺血后适应组大鼠实验性局灶性脑缺血的梗死体积减少,神经行为改善(P<0.05),但作用弱于缺血预适应组(P<0.01)。脑组织匀浆生化指标检测,缺血后适应和预适应可以增强SOD活性,降低MDA含量,与模型组比较,差异有统计学意义(P<0.01)。 结论缺血后适应可减轻局灶性脑缺血再灌注大鼠脑的病理性损伤,但作用弱于缺血预适应。  相似文献   

11.
This is a new method for the determination of creatine kinase isoenzyme MB activity in serum. The method uses direct activity measurement of creatine kinase B subunit activity after blocking of CK-M subunit activity by inhibiting antibodies. The test takes no longer than 15 min. The method yields an intra-serial C.V. of 2.0-12.9%, and a C.V. from day to day of 5.5%. The detection limit is 3.4 U/l creatine kinase MB. In the 95 cases with proven myocardial infarction several types of creatine kinase MB activity kinetics could be determined. The percentage of creatine kinase MB of peak CK-total is 6-25%, with a mean of 11.1%. The amount of creatine kinase MB with respect to total CK activity after reinfarction is higher than the amount after initial infarction.  相似文献   

12.
目的 探讨俯卧位通气对高海拔地区肺复张术(RM)治疗无效急性呼吸窘迫综合征(ARDS)患者的治疗作用.方法 从海拔2260m的地区医院筛选RM治疗无效的41例ARDS患者[平均氧合指数( PaO2/FiO2)较RM前升高<20%视为RM无效],依不同病因分为肺内源性ARDS组(ARDSp组)和肺外源性ARDS组(ARDSexp组),每组再按信封法随机分为俯卧位组和仰卧位组,即ARDSp俯卧位组(11例)、ARDSp仰卧位组(9例)、ARDSexp俯卧位组(10例)、ARDSexp仰卧位组(11例).在通气前及通气1、2、3、4h监测动脉血氧分压( PaO2)、PaO2/FiO2、静态顺应性(Cst)、气道阻力(Raw)的变化.结果 通气lh时,ARDSexp俯卧位组PaO2/FiO2( mm Hg,l mm Hg=0.133 kPa)即较通气前显著升高(157.4±40.6比129.3±48.7,P<0.05),并随通气时间延长呈持续增高趋势,4h达峰值(219.1 ±41.1);且ARDSexp俯卧位组通气3h内PaO2/FiO2较其他3组显著增高,另3组间则差异无统计学意义.ARDSp俯卧位组、ARDSexp俯卧位组通气4h时PaO2/FiO2均较相应仰卧位组显著增高(208.8±39.7比127.4±47.1,219.1±41.1比124.9±50.8,均P<0.05).4组通气前后Cst无显著改变,各组间差异也无统计学意义.ARDSp俯卧位组通气4h时Raw(cmH2O·L-1·s-1)较通气前显著降低(6.8±1.7比10.7±1.8,P<0.05),且明显低于其他3组;其他3组各时间点Raw组内及组间比较差异均无统计学意义.结论 俯卧位通气作为ARDS机械通气重要策略之一,可以改善RM无效高原ARDS患者的氧合,为抢救患者赢得宝贵的时间.  相似文献   

13.
The Department of Veterans Affairs (VA) in the USA operates a network of 172 medical centres which all utilize a hospital information system (HIS) which has been developed and is currently maintained by the VA. During the past several years, an image management and communication module has been developed, installed and clinically utilized at the Washington DC and Maryland VA Medical Centres. This image management and communication system, referred to as the decentralized hospital computer program (DHCP) imaging system, is fully integrated with a commercial picture archiving and communication system (PACS). The system is utilized to capture, archive, and display all images generated within the hospital including radiology, nuclear medicine, pathology, endoscopy, bronchoscopy, and dermatology, intraoperative photographs, ECG data, and a limited number of paper documents. The ultimate goal of the project is to have all patient text and image data available at any clinical workstation to any authorized user anywhere within the network of medical centres. Clinical requirements for an imaging workstation include ease of use, rapid and reliable access to the complete set of patient information, and images which are of acceptable quality to meet the requirements of the user and the subspecialty. Patient confidentiality and data security must be safeguarded at all times. Integration of the images with the remainder of the patient's database was found to be critical to the success of the project. The experience at the Washington and Maryland facilities suggests that an imaging system that is successfully integrated with a hospital information system can provide substantial clinical and economic benefits both within and among medical centres. Clinical acceptance and utilization of the system has been excellent, particularly in diagnostic radiology where DHCP Imaging has been interfaced to a commercial PAC system. Based upon this initial experience, the VA has begun to deploy the system throughout its large network of medical centres.  相似文献   

14.
15.
Myocardial elastography is a novel method for noninvasively assessing regional myocardial function, with the advantages of high spatial and temporal resolution and high signal-to-noise ratio (SNR). In this paper, in-vivo experiments were performed in anesthetized normal and infarcted mice (one day after left anterior descending coronary artery [LAD] ligation) using a high-resolution (30 MHz) ultrasound system (Vevo 770, VisualSonics Inc., Toronto, ON, Canada). Radiofrequency (RF) signals of the left ventricle (LV) in longitudinal (long-axis) view and the associated electrocardiogram (ECG) were simultaneously acquired. Using a retrospective ECG gating technique, 2-D full field-of-view RF frames were acquired at an extremely high frame rate (8 kHz) that resulted in high-quality incremental displacement and strain estimation of the myocardium. The incremental results were further accumulated to obtain the cumulative displacements and strains. Two-dimensional and M-mode displacement images and strain images (elastograms), as well as displacement and strain profiles as a function of time, were compared between normal and infarcted mice. Incremental results clearly depicted cardiac events including LV contraction, LV relaxation and isovolumetric phases in both normal and infarcted mice, and also evidently indicated reduced motion and deformation in the infarcted myocardium. The elastograms indicated that the infarcted regions underwent thinning during systole rather than thickening, as in the normal case. The cumulative elastograms were found to have higher elastographic SNR (SNR(e)) than the incremental elastograms (e.g., 10.6 vs. 4.7 in a normal myocardium, and 6.0 vs. 2.4 in an infarcted myocardium). Finally, preliminary statistical results from nine normal (m = 9) and seven infarcted (n = 7) mice indicated the capability of the cumulative strain in differentiating infracted from normal myocardia. In conclusion, myocardial elastography could provide regional strain information at simultaneously high temporal (>/=0.125 ms) and spatial ( approximately 55 microm) resolution as well as high precision ( approximately 0.05 microm displacement). This technique was thus capable of accurately characterizing normal myocardial function throughout an entire cardiac cycle, at the same high resolution, and detecting and localizing myocardial infarction in vivo.  相似文献   

16.
Objective: To identify patterns of nonfatal and fatal penetrating trauma among children and adults in New Mexico using ED and medical examiner data.
Methods: The authors retrospectively sampled in 5-year intervals all victims of penetrating trauma who presented to either the state Level-1 trauma center or the state medical examiner from a 16-year period (1978–1993). Rates of nonfatal and fatal firearm and stabbing injury were compared for children and adults.
Results: Rates of nonfatal injury were similar (firearm, 34.3 per 100,000 person-years; stabbing, 35.1). However, rates of fatal injury were significantly different (firearm, 21.9; stabbing, 2.7; relative risk: 8.2; 95% confidence interval: 5.4, 12.5). From 1978 to 1993, nonfatal injury rates increased for children (p = 0.0043) and adults (p < 0.0001), while fatal penetrating injury remained constant. The increase in nonfatal injury in children resulted from increased firearm injury rates. In adults, both stabbing and firearm nonfatal injury rates increased.
Conclusions: Nonfatal injury data suggest that nonfatal violence has increased; fatal injury data suggest that violent death rates have remained constant. Injury patterns vary by age, mechanism of trauma, and data source. These results suggest that ED and medical examiner data differ and that both are needed to guide injury prevention programs.  相似文献   

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Morphine, the most widely used mu-opioid analgesic for acute and chronic pain, is the standard against which new analgesics are measured. A thorough understanding of the pharmacokinetics of morphine is required in order to safely and effectively use this analgesic in a wide variety of patients with different levels of organ function. A MEDLINE search was conducted to identify literature published between 1966 and January 2002 relevant to the pharmacokinetics of morphine. These publications were reviewed and the literature summarized regarding unique and clinically important elements of morphine disposition relative to its parenteral administration (including intravenous, intramuscular, subcutaneous, epidural and intrathecal administration), absorption profile (immediate release, controlled release, and sublingual/buccal, and rectal administration), distribution, and its metabolism/ excretion. Special populations, including infants, elderly, and those with renal/liver failure, have a unique morphine pharmacokinetic profile that must be taken into account in order to maximize analgesic efficacy and reduce the risk of adverse events.  相似文献   

19.
目的 探讨手转胎头术失败的原因与分娩结局.方法 选择2008年1月至2010年12月于我院住院分娩的持续性枕横位、枕后位产妇198例,根据行手转胎头术后结果分为成功组126例、失败组72例.比较两组分娩结局,对比分析失败原因.结果 失败组胎儿体质量≥3500 g的发生率[76.4%(55/72)]明显高于成功组[31.7%(40/126)],差异有统计学意义(x2=30.177,P=0.001)、失败组宫缩乏力发生率[58.3%(42/72)]高于成功组[38.1% (48/126)],差异有统计学意义(x2=7.569,P=0.006)、失败组骨盆临界或轻度狭窄发生率[38.9% (28/72)]高于成功组[23.8%(30/126)],差异有统计学意义(x2 =5.030,P=0.002)、失败组手转胎头时机不当(宫口开大<6 cm、胎头位于坐骨棘上及宫口开大8~10 cm、胎头位于坐骨棘下≥2 cm)发生率[61.1%(44/72)]高于成功组[38.9%(49/126)],差异有统计学意义(x2=9.084,P=0.003).失败组母儿并发症(产后出血、产褥病率、胎儿窘迫、新生儿窒息)发生率高于成功组(x2 =9.586,P=0.002、x2=9.334,P=0.002、x2=5.910,P=0.015、x2=5.240,P=0.022)、失败组剖宫产发生率[72.2%(52/72)]明显高于成功组[34.1 %(43/126),x2=26.641,P=0.001)].结论 手转胎头术能使难产变顺产,降低剖宫产率,减少母儿并发症,但须积极预防、处理导致手转胎头术失败的原因,对矫正失败后继续矫正及试产应慎重.  相似文献   

20.
ABSTRACT

The Cochrane Library of Systematic Reviews is published quarterly. Issue 4 for 2009 contains 4027 complete reviews, 1906 protocols for reviews in production, and 11447 one-page summaries of systematic reviews published in the general medical literature. In addition, there are citations of 600,000 randomized controlled trials, and 12,200 cited papers in the Cochrane methodology register. The health technology assessment database contains over 7500 citations. This edition of the Library contains 90 new reviews, of which 19 have potential relevance for practitioners in pain and palliative medicine.  相似文献   

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