巴曲酶对缺血再灌注后凋亡相关基因时效研究

目的:探讨巴曲酶对沙土鼠前脑缺血再灌注损伤后海马CA1区神经元凋亡相关基因Bcl-2、Bax表达的影响及可能的作用机制。方法:分组采用双侧颈总动脉夹闭5min后再通,造成沙土鼠前脑缺血再灌注的损伤模型,在不同时间点腹腔注射巴曲酶对其进行治疗后,运用免疫组织化学方法,检测沙土鼠海马CA1区神经元中的Bcl-2、Bax免疫反应阳性细胞的数量。结果:与对照组相比,治疗组海马CA1区Bet-2表达明显增加,Bax表达降低,尤以缺血再灌注前6h、即刻、缺血再灌注后1h、3h及6h明显(P<0.01)。结论:巴曲酶可减少脑缺血再灌注后神经细胞的凋亡,发挥脑保护作用;其作用存在明显时效关系,机理可能与增强Bcl-2的表达及抑制Bax的表达有关。     

巴曲酶对缺血再灌注沙土鼠海马CA1区神经元的保护作用

目的：探讨巴曲酶对沙土鼠脑缺血再灌注神经元保护作用的可能机制。方法：蒙古沙土鼠63只分为巴曲酶组45只，假手术组9只及对照组9只。对照组及巴曲酶组鼠制作缺血再灌注模型，假手术组仅行手术操作，不行缺血处理。巴曲酶组于缺血再灌注前0、0．5、1、3和6h时分别给予腹腔注射巴曲酶8BU／kg，每个时间点9只。缺血再灌注96h后3组鼠进行免疫组化SP法检测海马CA1区的Bcl-2、eNOS、VEGF及Akt蛋白的表达及电镜下神经元超微结构观察；并在光镜下计算海马CA1区的神经元阳性细胞数。结果：巴曲酶组使用巴曲酶后，Bcl-2、eNOS、VEGF及Akt蛋白表达明显增加，神经元阳性细胞数在各时间点与对照组比较差异均有显著性意义（P〈O．01），而巴曲酶组各个时间点间比较差异无统计学意义；超微结构显示巴曲酶各时间点抗细胞凋亡明显。结论：巴曲酶具有明显的海马CA1区的神经元保护作用，其机制可能是通过其上调Beb2、eNOS、VEGF及Akt蛋白的表达。     

东菱迪芙与依达拉奉联合应用对大鼠脑缺血损伤的研究

目的探讨东菱迪芙与依达拉奉联合应用对大鼠脑缺血损伤的影响。方法成年健康雄性Wistar大鼠100只,采用改良线栓法制备大鼠大脑中动脉闭塞(MCAO)脑缺血再灌注模型,随机分为5组,即假手术组(正常组)、缺血再灌注组、东菱迪芙治疗组、依达拉奉治疗组、联合用药治疗组。运用组织化学染色技术,检测脑梗死体积;运用循环酶法,检测Hcy水平;运用免疫比浊法,检测hs-CRP浓度变化。结果 1脑缺血再灌注24h后大鼠脑梗死体积显示,东菱迪芙组、依达拉奉组、联合用药组与缺血再灌注组比较,脑梗死体积均缩小,每组间均有显著性差异(P0.05);联合用药组与东菱迪芙组、依达拉奉组间比较有统计学差异(P0.05)。2Hcy检测结果显示,缺血再灌注组显著高于正常组(P0.05);东菱迪芙组显著低于缺血再灌注组(P0.05);依达拉奉组显著低于缺血再灌注组(P0.05);东菱迪芙组显著低于依达拉奉组(P0.05);联合用药组显著低于单药组(P0.05)。3超敏C-反应蛋白的测定结果显示,缺血再灌注组显著高于正常组(P0.05);依达拉奉组显著低于缺血再灌注组(P0.05);东菱迪芙组显著低于缺血再灌注组(P0.05);东菱迪芙组显著低于依达拉奉组(P0.05);联合用药组显著低于单药组(P0.05)。结论 1东菱迪芙与依达拉奉通过缩小急性期脑梗死的梗死体积,降低Hcy和超敏C-反应蛋白水平,可有效减轻脑缺血损伤,均具有脑保护作用。2东菱迪芙与依达拉奉联合应用较单用东菱迪芙治疗或依达拉奉治疗其治疗效果更为显著。     

依达拉奉联合牛磺酸对脑缺血再灌注损伤大鼠保护作用的实验研究

目的 探讨依达拉奉及牛磺酸对大鼠脑缺血再灌注损伤的影响及作用机制.方法 制备大鼠大脑中动脉缺血-再灌注模型,分别测定血清丙二醛(MDA)的含量,脑组织Bcl-2蛋白表达和凋亡细胞数.结果 与再灌注组比较,依达拉奉组、牛磺酸组及联合用药组的血清MDA浓度及凋亡细胞数明显减小,Bcl-2蛋白表达明显增加,差异具有统计学意义.结论 依达拉奉及牛磺酸对脑缺血再灌注损伤有保护作用,其机制可能与其清除氧自由基及上调Bcl-2的表达有关.     

依达拉奉对大鼠局灶性脑缺血再灌注后p-Bad的作用

目的：探讨促凋亡蛋白Bad的磷酸化p-Bad在局灶性脑缺血再灌注中的表达及依达拉奉的作用机制。方法：建立局灶性脑缺血再灌注大鼠模型;HE染色观察脑组织形态病理学变化;免疫组织化学法测定大鼠脑缺血再灌注不同时间磷酸化Bad的平均光密度值（A值）。结果：与假手术组比较,p-Bad在缺血再灌注2 h明显升高,于4 h达到峰值（P〈0.05）,随灌注时间延长表达逐渐减少并低于假手术组;依达拉奉干预组阳性表达在各时间点明显增加（P〈0.05）。结论：脑缺血再灌注损伤可能导致Bad磷酸化活性增强,依达拉奉可通过上调p-Bad来发挥脑保护作用。     

神经生长因子预处理对沙土鼠全脑缺血/再灌注损伤脑神经细胞凋亡及Bcl-2和Bax蛋白表达的影响

目的探讨神经生长因子(NGF)预处理对沙土鼠全脑缺血/再灌注(I/R)损伤的脑保护作用的可能机制及最佳给药时间窗。方法采用夹闭沙土鼠双侧颈总动脉造成全脑I/R损伤模型。采用NGF侧脑室注射法进行预处理。沙土鼠30只随机分为5组,每组6只:假手术组(A组)、I/R损伤组(B组)、NGF预处理12、24和48h组(C、D、E组),除A组外各组分别于脑缺血20min、再灌注72h后处死取标本。用末端脱氧核苷酸转移酶介导的dUTP缺口末端标记法(TUNEL)检测沙土鼠全脑I/R损伤后脑皮质及海马CA1区凋亡神经细胞,用免疫组化法检测凋亡相关调控基因Bcl-2、Bax蛋白的表达。结果与B组比较,NGF预处理各组可显著减少沙土鼠全脑I/R损伤后脑皮质及海马CA1区神经细胞凋亡数目(P均<0.05),诱导Bcl-2蛋白及抑制Bax蛋白的表达(P均<0.05),其中以NGF预处理48h时脑皮质及海马CA1区细胞凋亡指数和Bax蛋白表达的阳性细胞指数最低,Bcl-2蛋白表达的阳性细胞指数最高。结论NGF预处理能明显减轻沙土鼠全脑I/R损伤引起的神经细胞凋亡,而以NGF预处理48h对脑保护效果最好;其抑制神经细胞凋亡的机制可能是通过调节凋亡相关调控基因Bcl-2及Bax的不同表达来发挥作用。     

巴曲酶联合依达拉奉治疗急性脑梗死的效果观察及护理

[目的]观察巴曲酶联合依达拉奉治疗急性脑梗死的效果观察,总结其护理.[方法]将80例急性脑梗死病人随机分为观察组及对照组,每组40例,两组均给予常规治疗,对照组应用依达拉奉,观察组应用巴曲酶联合依达拉奉治疗.比较两组病人的治疗效果.[结果]观察组总有效率为95.0%,对照组为82.5%,观察组总有效率高于对照组(P＜0.05).[结论]巴曲酶联合依达拉奉治疗急性脑梗死的效果明显.     

巴曲酶联合依达拉奉治疗急性脑梗死的效果观察及护理

[目的]观察巴曲酶联合依达拉奉治疗急性脑梗死的效果观察,总结其护理。[方法]将80例急性脑梗死病人随机分为观察组及对照组,每组40例,两组均给予常规治疗,对照组应用依达拉奉,观察组应用巴曲酶联合依达拉奉治疗。比较两组病人的治疗效果。[结果]观察组总有效率为95.0%,对照组为82.5%,观察组总有效率高于对照组（P〈0.05）。[结论]巴曲酶联合依达拉奉治疗急性脑梗死的效果明显。     

脑源性神经营养因子预处理对沙土鼠脑缺血-再灌注损伤的影响

目的 探讨脑源性神经营养因子(brain-derived neurotrophic factor,BDNF)预处理对沙土鼠脑缺血-再灌注(ischemia-reperfusion,I/R)后神经细胞凋亡及Bcl-2、Bax蛋白表达的影响.方法 蒙古种沙土鼠48只,随机分为6组,每组各8只:正常对照组(C);缺血-再灌注组(I/R),全脑缺血20 min后再灌注24 h;BDNF预处理6,12,24,48 h组(PR6,PR12,PR24,PR48),PR6,PR12,PR24,PR48各组分别于脑缺血前6,12,24,48 h经侧脑室注射BDNF(0.5 μg/只)进行预处理,缺血20 min后分别再灌注24 h.实验地点在贵阳医学院动物实验中心.采用夹闭沙土鼠双侧颈总动脉20 min后去除动脉夹使血流再通的方法制作全脑I/R损伤模型,夹闭过程中出现瞳孔散大、对光反射消失及翻正反射消失等则说明产生全脑缺血.除C组外的所有动物分别于脑缺血20 min再灌注24 h结束时断头取脑,取视交叉后1～4 mm处的额叶皮层组织制备石蜡切片,TUNEL法检测脑皮层凋亡神经细胞,免疫组化法检测Bcl-2,Bax蛋白的表达.统计分析采用方差分析法.结果 C组未检测到凋亡细胞及Bcl-2,Bax蛋白阳性表达细胞;I/R组及BDNF预处理各组沙土鼠脑皮层均可检测到凋亡细胞,且BDNF预处理各组细胞凋亡指数均明显低于I/R组,P值均为0.000;与I/R组比较,BDNF预处理各组脑皮层Bcl-2蛋白阳性细胞指数均显著增高,而Bax蛋白的阳性细胞指数均显著降低,P值均为0.000;BDNF预处理各组中以6,12 h预处理组的细胞凋亡指数及Bax蛋白阳性细胞指数较低,P值分别为0.056和0.001,而Bcl-2蛋白阳性细胞指数较高,P值为0.005.结论 不同时间窗的BDNF预处理均能不同程度的减轻脑I/R后神经细胞凋亡,有明显脑保护作用,以脑I/R损伤前6,12 h时间窗内给予BDNF预处理的脑保护效果较明显;其机制可能是通过上调Bcl-2蛋白的表达及抑制Bax蛋白的表达而实现.     

依达拉奉对气腹大鼠肝内胆管上皮细胞凋亡、Bcl-2表达的影响

目的:探讨氧自由基清除剂依达拉奉能否减轻气腹大鼠肝内胆管上皮细胞的再灌注损伤。方法:24只SD雄性大鼠,随机分成假气腹组(S组)、气腹组(P组)和依拉达奉干预组(E组);P、E组维持4h10mmHg压力气腹。气腹终止前30minE组大鼠经阴茎背静脉注射氧自由基清除剂依达拉奉3mg/kg,P组给予等量生理盐水。气腹放气后6h取血清测定肝功能,取左肝内叶肝组织,TUNEL染色测定肝内胆管上皮细胞的凋亡指数,免疫组化检测肝内胆管上皮细胞内Bcl-2和Bax蛋白表达。结果:与S组比较,P组ALP、TBA水平明显升高(P<0.05)、肝内胆管上皮细胞Bcl-2蛋白HIS评分降低(P<0.01)、凋亡指数升高(P<0.01);E组各项指标较P组显著好转。结论:气腹引发的缺血/再灌注导致胆管上皮细胞内的Bcl-2蛋白低表达,细胞凋亡增加,胆道功能损伤;氧自由基清除剂依达拉奉可减轻损伤程度。     

Determination of creatine kinase isoenzyme MB activity in serum using immunological inhibition of creatine kinase M subunit activity. Activity kinetics and diagnostic significance in myocardial infarction.

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.     

Dissociable correlates of two classes of retrieval processing in prefrontal cortex

Although substantial evidence suggests that the prefrontal cortex (PFC) implements processes that are critical for accurate episodic memory judgments, the specific roles of different PFC subregions remain unclear. Here, we used event-related functional magnetic resonance imaging to distinguish between prefrontal activity related to operations that (1) influence processing of retrieval cues based on current task demands, or (2) are involved in monitoring the outputs of retrieval. Fourteen participants studied auditory words spoken by a male or female speaker and completed memory tests in which the stimuli were unstudied foil words and studied words spoken by either the same speaker at study, or the alternate speaker. On "general" test trials, participants were to determine whether each word was studied, regardless of the voice of the speaker, whereas on "specific" test trials, participants were to additionally distinguish between studied words that were spoken in the same voice or a different voice at study. Thus, on specific test trials, participants were explicitly required to attend to voice information in order to evaluate each test item. Anterior (right BA 10), dorsolateral prefrontal (right BA 46), and inferior frontal (bilateral BA 47/12) regions were more active during specific than during general trials. Activation in anterior and dorsolateral PFC was enhanced during specific test trials even in response to unstudied items, suggesting that activation in these regions was related to the differential processing of retrieval cues in the two tasks. In contrast, differences between specific and general test trials in inferior frontal regions (bilateral BA 47/12) were seen only for studied items, suggesting a role for these regions in post-retrieval monitoring processes. Results from this study are consistent with the idea that different PFC subregions implement distinct, but complementary processes that collectively support accurate episodic memory judgments.     

俯卧位通气对高海拔地区肺复张治疗无效急性呼吸窘迫综合征患者氧合的影响

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.     

Digital imaging among medical facilities

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.     

Myocardial elastography at both high temporal and spatial resolution for the detection of infarcts

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.     

Clinical Pharmacokinetics of Morphine

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.