电磁脉冲对海马神经元的损伤及其对[Ca2+]i的影响

背景:电磁脉冲照射可影响实验大鼠的学习记忆功能,并造成大鼠海马组织损伤和超微结构改变。目的:观察电磁脉冲对离体培养的海马神经元的损伤效应及其对[Ca2 ]i的影响,以深入分析电磁脉冲致脑损伤的可能机制。设计:随机对照动物实验。单位:承德医学院病理教研室。材料:Wistar乳鼠若干只,雌雄各半。电磁脉冲辐射源:高场强电磁脉冲模拟源。方法:实验于2004-03/12分别在军事医学科学院和承德医学院完成。Wistar乳鼠若干只,麻醉下断头取脑,分离海马组织,调整细胞悬液浓度至5×108L-1接种。分组:①培养细胞分为对照组和照射组,于照射后即刻(0h)收集细胞进行形态学观察和胞内游离钙离子浓度测定;②另培养细胞分为对照组和照射后0h组和12h组,进行细胞凋亡和坏死率的测定。(培养细胞用量:每项检查每组1个培养瓶,重复3次。)电磁脉冲辐射条件为6×104V/m,脉冲上升时间为20ns,脉宽为30μs,频率为2.5脉冲/min,作用2min。原代培养的海马神经元经电磁脉冲辐射后,倒置相差显微镜下观察照射前后神经元形态学变化;FACS法检测细胞凋亡和坏死;Fluo-3-AM荧光探针负载、激光共聚焦显微镜扫描测定神经元胞内游离钙离子浓度[Ca2 ]i。主要观察指标:神经元形态学变化;细胞凋亡率和坏死率;胞内游离钙离子浓度[Ca2 ]i。结果:①电磁脉冲辐射后即刻,神经细胞逐渐发生液化,神经元突起回缩、变性。②电磁脉冲辐射后12h凋亡率较辐射后即刻有所恢复,但与对照组相比均显著增加[(59.27±1.27)%,(72.17±6.21)%,(17.45±5.63)%,P<0.05]。③在辐射后即刻和12h坏死率比对照组升高,但差异无统计学意义[(13.71±2.31)%,(11.96±1.04)%,(8.45±0.67)%,P>0.05]。④电磁脉冲辐射后即刻[Ca2 ]i荧光强度显著高于对照组(107.34±26.14,54.93±16.08,P<0.05)。结论:电磁脉冲致海马神经元形态学损伤、坏死与凋亡率增加,神经元内的Ca2 荧光强度明显增加。     

电磁脉冲对海马神经元的损伤及其对[Ca^2＋]i的影响

背景：电磁脉冲照射可影响实验大鼠的学习记忆功能，并造成大鼠海马组织损伤和超微结构改变。 目的：观察电磁脉冲对离体培养的海马神经元的损伤效应及其对[Ca^2＋]i的影响，以深入分析电磁脉冲致脑损伤的可能机制。 设计：随机对照动物实验。 单位：承德医学院病理教研室。 材料：Wistar乳鼠若干只，雌雄各半。电磁脉冲辐射源：高场强电磁脉冲模拟源。 方法：实验于2004—03／12分别在军事医学科学院和承德医学院完成。Wistar乳鼠若干只，麻醉下断头取脑，分离海马组织，调整细胞悬液浓度至5&;#215;10^8L^-1接种。分组：①培养细胞分为对照组和照射组，于照射后即刻（0h）收集细胞进行形态学观察和胞内游离钙离子浓度测定；②另培养细胞分为对照组和照射后0h组和12h组，进行细胞凋亡和坏死率的测定。（培养细胞用量：每项检查每组1个培养瓶，重复3次。）电磁脉冲辐射条件为6&;#215;10^4V／m，脉冲上升时间为20ns，脉宽为30μs，频率为2．5脉冲／min，作用2min。原代培养的海马神经元经电磁脉冲辐射后，倒置相差显微镜下观察照射前后神经元形态学变化；FACS法检测细胞凋亡和坏死；Fluo-3-AM荧光探针负载、激光共聚焦显微镜扫描测定神经元胞内游离钙离子浓度[Ca^2＋]i。 主要观察指标：神经元形态学变化；细胞凋亡率和坏死率；胞内游离钙离子浓度[Ca^2＋]。 结果：①电磁脉冲辐射后即刻，神经细胞逐渐发生液化，神经元突起回缩、变性。②电磁脉冲辐射后12h凋亡率较辐射后即刻有所恢复，但与对照组相比均显著增加[（59．27&;#177;1．27）％，（72．17&;#177;6．21）％，（17．45&;#177;5．63）％，P〈0．051。③在辐射后即刻和12h坏死率比对照组升高，但差异无统计学意义[（13．71&;#177;2．31）％，（11．96&;#177;1．04）％，（8．45&;#177;0．67）％，P〉0．05]。④电磁脉冲辐射后即刻[Ca^2＋]i荧光强度显著高于对照组（107．34&;#177;26．14，54．93&;#177;16．08，P〈0．05）。 结论：电磁脉冲致海马神经元形态学损伤、坏死与凋亡率增加，神经元内的Ca^2＋荧光强度明显增加。     

大鼠局灶性脑梗死后神经细胞凋亡与坏死的时空动态演变

目的:探讨大鼠局灶性脑梗死后神经细胞凋亡与坏死的时间、空间分布的动态演变及二者时空、时效关系的比较。方法:采用光化学法制作大鼠局灶性脑梗死的模型,利用苏木精-伊红染色与TUNEL技术观察局灶性脑梗死3～48h,3～6d后神经细胞凋亡与坏死情况。结果:坏死细胞主要集中于梗死区,凋亡细胞分布于半暗带区,二者均呈半球状向四周放射性扩展;光照后3h梗死中心有大量坏死细胞出现,而凋亡细胞于梗死后6h才出现,随着梗死时间的延长,二者均有明显的增加,坏死细胞于梗死后24h达高峰,凋亡的神经细胞在3d达高峰。结论:局灶性脑梗死后坏死细胞主要位于梗死区,凋亡细胞主要分布于半暗带区,并均呈半球状向四周放射性扩展。细胞凋亡的出现较晚,可能使抗凋亡成为治疗脑梗死的一种有效的途径之一。     

大鼠局灶性脑梗死后神经细胞凋亡与坏死的时空动态演变

目的：探讨大鼠局灶性脑梗死后神经细胞凋亡与坏死的时间、空间分布的动态演变及二时空、时效关系的比较。方法：采用光化学法制作大鼠局灶性脑梗死的模型，利用苏木精-伊红染色与TUNEL技术观察局灶性脑梗死3～48h，3～6d后神经细胞凋亡与坏死情况。结果：坏死细胞主要集中于梗死区，凋亡细胞分布于半暗带区，二均呈半球状向四周放射性扩展；光照后3h梗死中心有大量坏死细胞出现，而凋亡细胞于梗死后6h才出现，随着梗死时间的延长，二均有明显的增加，坏死细胞于梗死后24h达高峰，凋亡的神经细胞在3d达高峰。结论：局灶性脑梗死后坏死细胞主要位于梗死区，凋亡细胞主要分布于半暗带区，并均呈半球状向四周放射性扩展。细胞凋亡的出现较晚，可能使抗凋亡成为治疗脑梗死的一种有效的途径之一。     

鸦胆子油乳对膀胱癌细胞系BIU-87坏死与凋亡的影响

目的探讨鸦胆子油乳对膀胱癌BIU 87细胞坏死与凋亡的影响及其可能的作用机制。方法将不同浓度的鸦胆子油乳加入体外培养的BIU 87细胞 ,用流式细胞仪检测细胞凋亡与坏死比例、并检测线粒体膜电位 (MMP) ,用激光共聚焦显微镜观察细胞色素C分布。结果高浓度鸦胆子油乳作用 4h后 ,肿瘤细胞MMP明显降低 ,2 4h后多数细胞发生坏死 ,与对照组相比有非常显著性差异 (P <0 0 1) ;低浓度鸦胆子油乳作用 6h后 ,诱导细胞色素C释放 ,2 4h后可见典型的凋亡现象 ,与对照组相比有显著性差异 (P <0 0 5 )。结论鸦胆子油乳高浓度主要诱导肿瘤细胞坏死 ,低浓度诱导细胞凋亡。     

电磁脉冲对海马神经元的损伤效应及其对［Ca2+］i的影响

目的观察电磁脉冲(EMP)对海马神经元的损伤效应及其对[Ca2+]i的影响,以深入探讨EMP致脑损伤的机制. 方法 EMP辐射条件为6×104V/m,脉冲上升时间为20 ns,脉宽为30 μs,频率为2.5脉冲/min,作用2 min.原代培养的海马神经元经EMP辐射后,采用MTT法对细胞活力进行测定;FACS法检测细胞凋亡和坏死;Fluo-3-AM荧光探针负载、激光共聚焦显微镜扫描测定神经元胞内游离钙离子浓度,即[Ca2+]i. 结果细胞被EMP辐射后0～6 h活力明显下降(P<0.05),12 h开始回升,24 h基本接近正常水平;EMP辐射后0～12 h细胞凋亡率显著升高,坏死也有增加;EMP辐射后即刻引起神经元内的Ca2+荧光强度明显增加. 结论 EMP致海马神经元活力下降、凋亡增加、胞内钙超载.     

参麦注射液对大鼠海马神经细胞凋亡的影响

目的以缺氧/缺糖再给氧为模型,观察参麦注射液对神经细胞凋亡的抑制作用。方法流式细胞术检测凋亡细胞百分率,激光共聚焦扫描显微镜检测细胞内Ca2+浓度,荧光显微镜观察细胞形态学变化和坏死百分率。结果缺氧/缺糖5h后再给氧可诱导神经细胞凋亡和细胞坏死,并显著增加细胞内Ca2+浓度和LDH的释放。与对照组相比有显著性差异(P<0.01)参麦注射液能显著降低神经细胞凋亡及坏死的百分率,降低细胞内Ca2+浓度,减少LDH的释放,其作用随剂量增加而增加。结论参麦注射液具有拮抗海马神经细胞凋亡的作用,这种作用可能与其能降低细胞内Ca2+浓度有关。     

参麦注射液对大鼠海马神经细胞凋亡的影响

目的：以缺氧／缺糖再给氧为模型，观察参麦注射液对神经细胞凋亡的抑制作用。方法：流式细胞术检测凋亡细胞百分率，激光共聚焦扫描显微镜检测细胞内Ｃa^2 浓度，荧光显微镜观察细胞形态学变化和坏死百分率。结果：缺氧／缺糖５h后再给氧可诱导神经细胞凋亡和细胞坏死，并显著增加细胞内Ｃa^2 浓度和ＬＤＨ的释放。与对照组相比有显著性差异（Ｐ＜０．０１）参考注射液能显著降低神经细胞凋亡及坏死的百分率，降低细胞内Ｃa^2 浓度，减少ＬＤＨ的释放，其作用随剂量增加而增加。结论：参麦注射液只有拮抗海马神经细胞凋亡的作用，这种作用可能与其能降低细胞内Ｃa^2 浓度有关。     

干预丝裂原活化蛋白激酶信号通路对电磁辐射诱导神经细胞凋亡的影响

目的:研究电磁辐射致神经细胞损伤的具体规律,揭示MAPK信号通路在电磁辐射诱导神经细胞凋亡中的作用。方法:实验于2002-02/07在第三军医大学劳动卫生学教研室进行。未经预抑制剂预处理的PC12细胞接受65mW/cm2电磁波辐照,设定辐照后0,3,12,24h4个时相点,经SB203580和U0126单独或联合预处理后PC12细胞,设定辐照前及辐照后3,24h3个时相点,采用Annex-in-V标记经流式细胞仪检测细胞凋亡。结果:电磁波辐照后即刻开始诱导明显的PC12细胞凋亡,3h及12h后凋亡细胞进一步明显增多,凋亡率为20.5%和23%(P<0.01),24h后细胞凋亡再次显著增加,并达到峰值31.4%(P<0.01)。单独使用SB203580及与U0126联合预处理后,细胞凋亡明显减轻,而单独使用U0126预处理对细胞调亡无明显影响。结论:电磁辐射可以明显诱导PC12细胞凋亡,并且细胞凋亡可能是电磁辐射致中枢神经损伤的主要原因。电磁辐射诱导PC12细胞凋亡主要是通过丝裂原活化蛋白激酶P38信号通路,还可能存在c-Jun氨基末端激酶以及丝裂原活化蛋白激酶转导系统以外的信号通路对电磁辐射诱导神经细胞凋亡进行调控。     

参麦注射液对天鼠海马神经细胞凋亡的影响

目的以缺氧/缺糖再给氧为模型,观察参麦注射液对神经细胞凋亡的抑制作用.方法流式细胞术检测凋亡细胞百分率,激光共聚焦扫描显微镜检测细胞内Ca2+浓度,荧光显微镜观察细胞形态学变化和坏死百分率.结果缺氧/缺糖5h后再给氧可诱导神经细胞凋亡和细胞坏死,并显著增加细胞内Ca2+浓度和LDH的释放.与对照组相比有显著性差异(P<0.01)参麦注射液能显著降低神经细胞凋亡及坏死的百分率,降低细胞内Ca2+浓度,减少LDH的释放,其作用随剂量增加而增加.结论参麦注射液具有拮抗海马神经细胞凋亡的作用,这种作用可能与其能降低细胞内Ca2+浓度有关.     

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.     

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.     

手转胎头术失败的原因与分娩结局临床分析

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.     

Evidence-Based Pain Management and Palliative Care in Issue Four for 2009 of The Cochrane Library

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.     

Wie zuverlässig sind Angaben zu nichtentzündlichen ausgedehnten Schmerzen?

ZusammenfassungFragestellung Es wurde geprüft, wie sich der Differenziertheitsgrad zweier Schmerzmessmethoden auf Angaben zur Ausgedehntheit klinischer Schmerzen auswirkt. Zugleich wurde der Referenzzeitraum variiert, über den die Patienten berichten sollten.Methode Erfasst wurde der Einfluss zu Lasten der Befragungsdifferenziertheit durch den Vergleich zweier Körperschema-Bildvorlagen. Drei Referenzzeiträume (Schmerz aktuell, letzte Woche, letztes halbes Jahr) wurden vorgegeben.Ergebnisse Patienten mit ausgedehnten Schmerzen gaben bei differenzierter Befragung um so mehr Schmerzen an, je weiter die Schmerzen zurück lagen und je größer der Berichtszeitraum war. Patienten mit gelenknahen Schmerzen gaben bei hoch differenzierter Befragung weniger ausgedehnte Schmerzen in der Vergangenheit an als bei globaler Einschätzung. Patienten mit Rückenschmerzen berichteten bei differenzierter Befragung zum aktuellen Schmerz über weniger ausgedehnte Schmerzen als bei globaler Befragung.Schlussfolgerung Die Angaben zur Schmerzausdehnung variieren vor allem bei Patienten mit ausgedehnten Schmerzen in Abhängigkeit von der Differenziertheit der Befragung. In diesen Fällen ist die Wahrscheinlichkeit erhöht, dass sich die Beschwerdesymptomatik zumindest teilweise erst in der Reaktion auf die situativen Befragungsbedingungen konstituiert und daher nicht auf andere Befragungsbedingungen generalisiert werden kann.