内毒素休克时循环血中一氧化氮的动态变化及其发生机制

为探讨内毒素休克时循环血中一氧化氮(NO)的动态变化及其可能的发生机制。方法:给新西兰白兔一次性静注大肠杆菌内毒素(LPS,8.0×10~9cfu/kg.B.w)后,观察平均动脉压(MAP)、血浆肿瘤坏死因子—α(TNF—α)和NO_2~-(NO代谢终产物)水平、组织一氧化氮合酶(NOS)活性及器官功能变化。结果:一次性静注LPS后,MAP呈双相下降;血浆TNF—α活性呈陡直的单峰曲线;NO_2~-含量于30min迅速增高,6h达峰值,24h仍高于注射前;24h心组织中NOS活性明显高于肝、肺和肾组织;肝、肾功能损害进行性加重。结论:内毒素休克时NO的生成不但迅速增加,而且持续时间长,可能是继TNF—α之后生成的其它细胞因子作用的结果。     

L-NAME对鼠内毒素血症一氧化氮和肿瘤坏死因子-α释放的影响

目的：探讨L-NG-硝基精氨酸甲酸（L-NAME）在鼠内毒素血症中的作用。方法：用脂多糖（LPS）复制内毒素休克小鼠模型。实验动物随机分成4组：（1）正常对照组;（2）L-NAME组;（3）LPS组;（4）L-NAME LPS组,观测L-NAME对一氧化氮（NO）、肿瘤坏死因子-α（TNF-α）含量,脏器一氧化氮合酶（NOS）活性及肝、肾功能等的影响。结果：给予L-NAME后,血浆NO,TNF-α水平下降,脏器NOS活性降低,肝肾功能损害减轻,实验动物存活率明显提高。结论：抑制诱导型一氧化氮合酶（iNOS）是治疗内毒素休克的一个途径。     

休克淋巴液对大鼠肺微血管内皮细胞炎症介质表达的影响

目的 观察休克淋巴液对大鼠肺微血管内皮细胞(PMVECs)自由基及一氧化氮(NO)、肿瘤坏死因子-α(TNF-α)、白细胞介素-6(IL-6)表达的影响,进一步探讨休克淋巴液损伤PMVECs的机制.方法 原代培养大鼠PMVECs至第3代进行研究.无菌条件下复制大鼠重症失血性休克模型(动脉压40 mm Hg维持90 min,1 mm Hg=0.133 kPa).引流正常大鼠和休克大鼠肠系膜淋巴液及门静脉血,与PMVECs孵育6h,同时以胎牛血清(FBS)和无血清的DMEM培养液作为对照.逆转录-聚合酶链反应(RT-PCR)检测诱生型一氧化氮合酶(iNOS)、TNF-α和IL-6的mRNA表达;检测培养上清液中丙二醛(MDA)、NO、TNF-α和IL-6的含量.结果 体积分数为4%终浓度的休克淋巴液作用6 h后,PMVECs中iNOS、TNF-α和IL-6的mRNA表达以及培养上清液中MDA、NO、TNF-α和IL-6水平均显著高于空白对照组、正常淋巴液组、休克血浆组、正常血浆组和无血清对照组;且休克血浆作用PMVEC 6 h后的iNOS、TNF-α和IL-6的mRNA表达及培养上清液中NO水平均显著高于空白对照组、正常淋巴液组、正常血浆组和无血清对照组(P<0.05或P<0.01).结论 4%终浓度的休克淋巴液可致大鼠PMVECs中iNOS、TNF-α和IL-6的mRNA表达增强,促进自由基释放,从而诱导细胞损伤.     

正常淋巴液对内毒素休克大鼠肺组织髓过氧化物酶活性及膜泵的作用研究

目的观察外源性正常淋巴液对脂多糖（LPS）所致内毒素休克大鼠肺组织匀浆髓过氧化物酶（MPO）活性及肺组织细胞膜泵功能的作用，探讨其干预机制。方法雄性Wistar大鼠40只，按随机数字表法均分为内毒素组、淋巴液组、血浆组和对照组。除对照组外，其他各组应用LPS5mg／kg复制内毒素休克模型，对照组以等量生理盐水代替LPS；15min后，淋巴液组自颈静脉输入仅占全血量1／15的无细胞淋巴液；血浆组以血浆代替淋巴液；内毒素组和对照组以生理盐水代替淋巴液。给予LPS（或相应液体）后4h，制备体积分数为10％的肺组织匀浆，检测肺组织匀浆MPO及膜ATP酶的活性。结果与对照组相比，内毒素组和血浆组大鼠肺组织匀浆MPO活性显著增高、4种膜ATP酶活性均显著下降（P＜0．05或P＜0．01）。淋巴液组肺组织匀浆MPO活性显著高于对照组，Na^＋-K^--ATP酶活性显著低于对照组，两组比较差异均有显著性（P均＜0．05）；而Ca^2＋-ATP酶、Mg^2＋-ATP酶和Ca^2＋-Mg^2＋-ATP酶活性与对照组比较差异均无显著性（P均＞0．05）；淋巴液组肺组织匀浆MPO活性显著低于内毒素组及血浆组（P均＜0．01），4种膜ATP酶活性显著高于内毒素组及血浆组（P＜0．05或P＜0．01）。结论外源性正常淋巴液对内毒素休克所致的肺损伤具有干预作用，其机制可能与减少中性粒细胞激活、提升膜ATP酶活性有关。     

特异性清除循环肿瘤坏死因子-α对内毒素休克时肝细胞氧化应激的影响

目的　观察免疫吸附特异性清除循环肿瘤坏死因子-α(TNF-α)对内毒素休克时肝细胞氧化应激的影响,并探讨其与一氧化氮(NO)之间的关系。方法　给新西兰白兔一次性静注内毒素(LPS)80×109cfu/kg,免疫吸附组和空灌流组分别于1小时后经抗TNF-α单克隆抗体亲和免疫吸附柱或未偶联抗体的空灌流柱进行血液灌流2小时,对照组不予血液灌流,观察血浆NO-2和丙二醛(MDA)含量、全血超氧化物歧化酶(SOD)活力、肝组织中MDA含量和SOD活力以及肝功能变化。结果　免疫吸附治疗后,血浆和肝组织中MDA含量明显下降,全血和肝组织中SOD活力显著增高;血浆NO的生成显著减少,但又高于注射LPS前水平;肝功能损害明显减轻。结论　免疫吸附特异性清除循环TNF-α既明显抑制了内毒素休克时肝细胞氧化应激,又使NO浓度保持在一定范围内,可能是该方法能明显减轻内毒素性肝损害的重要原因。     

白介素—10和一氧化氮对内毒素诱导肺泡巨噬细胞核因子—кB活化及肿瘤坏死因子释放的调节

目的：探讨白介素－10和外源性一氧化氮（NO）对内毒素（LPS）诱导肺泡巨噬细胞（PAM）核因子－кB（NF－кB）活化及肿瘤坏死因子－α（TNF－α）基因表达的调节，为临床运用提供理论依据。方法：用支气管肺泡灌洗法收集PAM进行培养，分为正常对照组、LPS组、IL－10＋LPS组和NO＋LPS组。用凝胶电泳迁移率改变分析（EMSA）法和酶联免疫吸附（ELISA）法分别检测核提取物中NF－кB活性和细胞培养上清中TNF－α含量。结果：LPS组NF－кB活性和TNF－α含量在刺激后3显著高于对照组；IL－10＋LPS组和NO＋LPS组NF－кB活性和TNF－α含量均显著低于LPS组。结果：LPS诱导PMAM宾NF－кB活化，导致TNF－α基因表达增强；白介素－10和外源性NO可抑制NF－кB活化而减少TNF－α的释放。     

Th1/Th2类细胞因子失衡和一氧化氮合酶在内毒素休克性肺损伤中的作用机制

目的　观察内毒素 (LPS)诱导的急性肺损伤 (ALI)大鼠血Th1/Th2类细胞因子浓度以及肺组织一氧化氮合酶 (NOS)活性和NOS基因表达 ,以探讨它们在ALI中的发病机制。方法　采用颈静脉注入LPS复制大鼠急性肺损伤模型 ,用ELISA法检测其外周血单个核细胞产生IFN -γ、IL - 4水平及IFN -γ/IL - 4比值 ;用放射免疫 (RIA)的方法测定LPS注射后大鼠肺组织NOS活性 ;采用逆转录聚合酶链反应 (RT -PCR)检测LPS注射大鼠肺组织内源型一氧化氮合酶 (eNOS)、诱导型一氧化氮合酶 (iNOS)mRNA表达情况。结果　与正常对照组相比 ,急性肺损伤组外周血PBMC产生IFN -γ水平、IFN -γ/IL - 4比值明显升高 (P <0 0 5 ,P <0 0 0 1) ,而IL - 4水平差异无显著性 (P >0 0 5 ) ,同时伴随NOS活性 [( 0 30± 0 0 5 )U/mgpro]明显高于对照组 [( 0 2 4± 0 0 3) ,P <0 0 5 ]。iNOSmRNA表达( 0 70± 0 2 0 )显著高于对照组 (P <0 0 5 ) ,eNOSmRNA表达未见明显变化 (P >0 0 5 )。肺组织病理切片显示大鼠发生ALI。结论　LPS休克肺损伤时 ,体内存在Th1/Th2类细胞因子水平失衡 ,同时伴有NOS活性增高 ,而NOS的主要来源为iNOS基因表达增强     

电刺激迷走神经对感染性休克大鼠血浆肿瘤坏死因子α、一氧化氮合酶及一氧化氮的影响

目的 研究电刺激迷走神经对感染性休克大鼠血浆肿瘤坏死因子α(TNF-a)、一氧化氮合酶(NOS)及一氧化氮(NO)水平的影响.方法 成年雄性SD大鼠40只,采用盲肠结扎穿孔法(CLP)复制感染性休克模型,随机分为5组:假CLP组、CLP组、迷切组、电刺激左侧迷走神经组、电刺激右侧迷走神经组.各组动物均行颈总动脉置管连续监测平均动脉压,ELISA法检测血浆 TNF-α,生化法检测血浆中NOS活性和NO水平.结果 CLP组术后平均动脉血压进行性下降,2 h时血浆TNF-α、NOS及NO水平显著升高;与CLP组比较,电刺激组动物平均动脉压下降幅度减轻,血浆TNF-α、NOS及NO水平显著降低.结论 电刺激左、右迷走神经均可能缓解CLP致感染性休克大鼠的进行性血压下降,降低血浆TNF-α、NOS及NO水平,有助于抗休克.     

羟乙基淀粉对内毒素感染大鼠血浆细胞因子表达和单个核细胞NF—κB活性的影响

目的　研究羟乙基淀粉溶液 (HES 2 0 0 /0 5 )对内毒素腹腔感染大鼠炎症反应的影响 ,并探讨分子机制。方法　雄性Wistar大鼠随机分为对照组、内毒素组 (LPS 6mg/kg)、LPS HES组 (HES 3 75、7 5、15、30mL/kg)及HES对照组 (30mL/kg)。分别于LPS注入后 4h检测血浆肿瘤坏死因子 (TNF -α)和细胞因子诱导的中性粒细胞趋化因子 (CINC)浓度 ,2h检测循环血单个核细胞核转录因子kappaB(NF -κB)水平。结果　大鼠内毒素感染时血浆TNF -α和CINC浓度及单个核细胞NF -κB活性明显上升 (P <0 0 5 )。 3 75和 7 5mL/kgHES能明显降低TNF -α和NF -κB水平 (P <0 0 5 ) ;3 75、7 5和 15mL/kgHES能明显降低CINC水平 (P <0 0 5 )。结论　较低剂量HES具有抑制内毒素腹腔感染大鼠炎症反应的作用 ,这种作用的产生与其对NF -κB的抑制有关。HES对感染状态有保护作用。     

内毒素耐受大鼠肺部iNOS和NO表达的动态变化和意义

目的 研究内毒素血症时内毒素耐受大鼠肺部诱导型一氧化氮合酶(iNOS)、一氧化氮(NO)的动态变化.方法 72只SD大鼠随机分为对照组(NC组)和内毒素耐受组(ET组).腹腔注射小剂量内毒素(LPS),第1天0.1 mg/只;第2～5天0.5 mg/只,建立内毒素耐受模型.NC组腹腔注射同等剂量生理盐水.最后一次注射LPS 72 h后,两组均腹腔注射大剂量LPS(10 mg/kg).各组按注射LPS前(0 h),注射后2、4、6、12、24 h分为六小组(n=6).通过比色法(即Griess法)测量肺组织iNOS、NO、丙二醛(MDA)及髓过氧化物酶(MPO)含量.同时在第6、12 h取大鼠左下肺组织行组织病理形态学观察.用SPSS13.0统计软件进行统计分析.结果 NC组大鼠在大剂量LPS刺激后肺组织iNOS和NO在4 h开始升高,6～12 h达到高峰(P＜0.05);MDA和MPO含量在2 h即开始升高,4～12 h达到高峰(P＜0.05).ET组大鼠在大剂量LPS刺激前肺组织iNOS、NO、MDA和MPO即有微量升高(P＞0.05),大剂量LPS刺激后肺组织iNOS、NO、MDA和MPO亦有升高,但与NC组相比明显降低(P＜0.05).病理学检查显示,ET组肺组织损伤明显较NC组减轻.结论 内毒素耐受时,大剂量内毒素血症引起的大鼠肺部损伤减轻与肺部iNOS、NO低表达有关.     

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.