血管回声跟踪技术评价动脉血管弹性变化的动物实验

目的 应用血管回声跟踪(ET)技术评价兔腹主动脉粥样硬化动脉弹性变化,探讨其评价动脉硬化弹性变化的病理基础及应用价值.方法 雄性新西兰兔30只,随机分为三组,A组为对照组;B、C组为实验组,分别高脂喂养8周、12周.A、B两组于喂养8周,A、C两组于喂养12周时应用ET技术检测兔腹主动脉弹性参数(Ep)、僵硬化系数(β)、脉搏波传导速度(PwVp)、增大指数(AI)、顺应性(AC)等参数,同时对比观察腹主动脉二维超声及病理变化.结果 各组二维超声均未见明显腹主动脉管壁增厚及斑块形成.ET检测指标显示:C组Ep、β、PWVβ较A、B组高,AC低于A、B两组,差异有统计学意义(均P<0.05);AI各组间差异无统计学意义(P>0.05).病理检查B组腹主动脉内膜泡沫细胞形成,动脉弹力层及平滑肌层未见明显破坏.C组腹主动脉内膜大量胆固醇结晶形成,动脉弹力层及平滑肌层破坏断裂.结论 ET技术可早于二维超声发现腹主动脉粥样硬化时动脉弹性改变.当动脉粥样硬化引起其管壁弹力层、平滑肌层破坏时,ET即能检测到相关参数变化,因此弹力层、平滑肌层损伤可能是动脉弹性改变的病理基础.     

血流灰阶显像技术评价兔腹主动脉粥样硬化的实验研究

目的 探讨超声血流灰阶显像(BFI)技术对兔腹主动脉粥样硬化的诊断价值.方法 兔16只,高脂饮食喂养12周,建立兔腹主动脉粥样硬化模型.于实验前及实验后第4,8,12周末进行超声检查,检查兔腹主动脉前壁及后壁内-中膜厚度,观察斑块形成情况;对比启用BFI技术前后动脉内膜及斑块的显像差异,应用超声组织定征技术对内膜及斑块灰阶进行定量分析,并与病理检查对照.结果 使用BFI技术后,动脉内膜回声明显增强,部分斑块回声增强,且新发现4例软斑块.结论 BFI技术能显著提高动脉粥样硬化早期诊断的灵敏度和斑块的检出率.     

血管回声跟踪技术评价辛伐他汀对高脂喂养兔血管弹性的影响

目的 探讨血管回声跟踪技术评价辛伐他汀干预高脂喂养兔血管弹性的效果.方法 27只兔随机分成3组:正常对照组(A组)、高脂喂养组(B组)、高脂+辛伐他汀组(C组),各组分别于喂养第4周、第8周末超声检测腹主动脉(AO)及股动脉(FA)弹性,8周末处死兔并截取动脉,免疫组化法检测诱导型一氧化氮合酶(iNOS)蛋白表达.结果 B组兔于喂养第4周时FA僵硬度(β)、弹性系数(Ep)、脉搏波传导速度(PWVβ)值较A组升高,顺应性(AC)值较A组减低,差异有统计学意义(P＜0.05);AO于喂养第8周时β、Ep、PWVβ值较A组升高,AC值较A组减低,差异有统计学意义(P＜0.05).C组兔于喂养第8周时FAβ、Ep、PWVβ值较B组减低,AC值较B组升高,差异有统计学意义(P＜0.05),AO各指标与B组比较差异无统计学意义.结论 短期服用辛伐他汀能提高兔FA的血管弹性,AO则无明显改变.     

动脉粥样硬化兔斑块易损性的血管内超声评价

目的应用血管内超声（IVUS）技术评价易损斑块的影像学特征。方法30只实验兔给予球囊损伤腹主动脉＋高脂饲料喂养，12周末将实验兔随机分为A、B两组，在A组腹主动脉斑块处转染携带人野生型P53基因的重组腺病毒载体，2周后给予所有兔中国斑点蝰蛇毒（CRVV）和组胺触发，14周末进行体表超声、血管内超声和病理学检查。结果A组斑块破裂率较B组显著增高（P〈0．05）。IVUS示斑块破裂组的血管外弹力膜面积（EEMA）、斑块面积（PA）、管腔面积狭窄百分率（LAS%）及偏心指数（EI）显著大于未破裂组（P〈0．01～0．05）；斑块破裂组的内一中膜厚度（IMT）、收缩期峰值流速（Vp）显著大于未破裂组，而平均回声强度的校正值（AIIc％）显著低于未破裂组（P均〈0．05）。结论应用野生型P53基因转染可导致斑块的不稳定性，IVUS能够准确识别易损斑块，为临床早期发现易损斑块并预测斑块破裂提供了可靠的方法。     

高脂饲料喂养与动脉内膜球囊损伤结合建立兔腹主动脉粥样硬化模型

背景:以往研究多采用单纯饲喂高脂饲料、正常或高脂血症动物动脉内膜损伤致动脉粥样硬化狭窄模型.目的:拟采用喂养高脂饲料与动脉内膜球囊损伤相结合的方法建立腹主动脉粥样硬化的模型.设计、时间及地点:对比观察实验,于2007-01/03在解放军总医院动物实验中心完成.材料:新西兰白兔20只,随机分为单纯饲喂高脂饲料组、高脂饲料与动脉内膜损伤结合组,每组10只.高脂饲料由普通颗粒饲料+4%胆固醇+10%猪油组成+10%蛋黄粉组成.方法:单纯饲喂高脂饲料组单纯喂养高脂饲料,高脂饲料与动脉内膜损伤结合组喂养高脂饲料4周后,行腹丰动脉内膜球囊损伤术.主要观察指标:12周后取主动脉行病理检查,计算机计算脂纹脂斑厚度,内、中膜厚度,内膜厚度比值,并进行血清总胆固醇、三酰甘油和高密度脂蛋白胆固醇、低密度脂蛋白胆固醇的测定.结果:12周后,两组兔血脂血清总胆固醇、三酰甘油、高密度脂蚩白胆固醇、低密度脂蛋白胆固醇均升高,高脂饲料与动脉内膜损伤结合组升高更明显(P<0 05).喂养高脂饲料的两组动物均出现动脉粥样硬化斑块,横段而纤维斑块切片出现钙化.与单纯饲喂高脂饲料组比较,高脂饲料与动脉内膜损伤术结合组内膜明显增厚,形成了明显的斑块及纤维帽结构,斑块厚度与内中膜厚度比值增加明显(P<0.01).结论:所诱导产生的斑块与人类斑块成分具有一定相似性,包括斑块的纤维帽、钙化、脂核等,提示采用动脉内膜损伤与高脂饮食结合方式来制作动脉粥样硬化斑块的模型是可行的、实用的.     

超声结合病理评估多种制备兔腹主动脉粥样硬化斑块模型方法

目的采用多种方法制备兔腹主动脉粥样硬化斑块模型,寻求可靠的动脉粥样硬化斑块模型制备方法。方法采用单纯高脂喂养(对照组)、高脂喂养+腹主动脉球囊拉伤术(实验组1)、高脂喂养+注射小牛血清白蛋白(实验组2)、高脂喂养+腹主动脉球囊拉伤术+注射小牛血清白蛋白(实验组3)4种方法建立兔腹主动脉粥样斑块模型,对比评估斑块形成情况。结果实验组腹主动脉内中膜复合体厚度(IMT)均明显高于对照组,实验组与对照组兔腹主动脉粥样斑块回声类型的占比均有显著性差异,实验组粥样斑块形成数目明显多于对照组,其中实验组3的斑块数量较实验组1、实验组2多。结论高脂喂养+腹主动脉球囊拉伤术+注射小牛血清白蛋白是一种稳定、高效的兔腹主动脉粥样硬化斑块模型建立方法,其建模效果优于其他3种方法,是一种稳定、高效的建立斑块模型方法。     

血管内超声评价祛瘀消斑胶囊和辛伐他汀稳定易损斑块的作用

目的应用血管内超声技术（IVUS）评价祛瘀消斑胶囊和辛伐他汀对易损斑块的稳定作用。方法43只实验兔采用球囊损伤腹主动脉＋高脂饲料喂养;12周末改喂普通饲料并随机分为A（对照）、B（祛瘀消斑胶囊）、C（辛伐他汀）组,药物干预12周;24周末对3组实验兔斑块局部转染携带P53基因的腺病毒载体;26周末,应用蝰蛇毒和组胺进行药物触发。测定血脂并行体表超声、IVUS和病理学检测。结果与A组比较,B组和C组斑块破裂率显著降低（P均〈0.05）,血清总胆固醇（TC）、低密度脂蛋白胆固醇（LDL-C）（P〈0.05～0.01）、内中膜厚度（IMT）（P均〈0.01）、斑块面积（PA）（P均〈0.01）、管腔面积狭窄率（LAS%）（P均〈0.01）、病理测量IMT（P分别〈0.05和0.01）显著降低,平均回声强度的校正值（AIIc%）（P均〈0.05）、纤维帽厚度及纤维帽/IMT比值（P〈0.05～0.01）显著升高。C组TC和LDL-C（P分别〈0.05和0.01）,IMT（P〈0.05）,PA（P〈0.05）显著低于B组。结论祛瘀消斑胶囊和辛伐他汀能有效稳定易损斑块,IVUS可为观察各种干预治疗前后斑块的稳定性和消退提供一种可靠手段。     

不稳定斑块血管内超声特征的实验研究

目的　明确不稳定斑块的血管内超声 (IVUS)影像学特点。方法　 2 7只雄性新西兰纯种兔随机分成A组 (17只 )与B组 (10只 ) ,A组用球囊损伤腹主动脉 高脂喂养 10周 ,B组仅给予高脂喂养 10周。于 8周末将A组在腹主动脉斑块形成处转染携带人野生型 p5 3基因的重组腺病毒载体 ,于 10周末 ,两组实验兔分别给予中国斑点蝰蛇毒和组胺药物触发斑块破裂。应用IVUS分别测量、比较斑块破裂前的腹主动脉同一血管段中多个病变部位及其参考部位的IVUS指标 ,明确不稳定斑块的IVUS影像学特点。结果　破裂与未破裂斑块的参考部位的血管外弹力膜面积 (EEMA)、管腔面积、斑块面积及管腔面积狭窄率相比 ,差异无显著性意义 (P >0 .0 5 )。与未破裂斑块相比较 ,破裂斑块具有较大的偏心性 (P <0 .0 0 1) ,EEMA、斑块面积及管腔面积狭窄率明显大于前者 ,差异有显著性意义 (均P <0 .0 0 1)。破裂斑块呈现明显的正性重构 ,而稳定斑块主要表现为负性重构。结论　IVUS应用于已建立的动脉粥样硬化不稳定斑块动物模型上 ,能够准确地识别动脉粥样硬化不稳定斑块 ,本研究为临床早期发现不稳定斑块并预测斑块破裂奠定了实验基础。     

超声技术评价兔主动脉的动脉粥样硬化

目的　评价超声技术在检测动脉粥样硬化兔主动脉形态学与组织特征方面的应用价值。方法　将 40只兔分为正常组与动脉粥样硬化组 (AS) ,于实验开始、4、8、12周末行超声检测 :包括主动脉内中膜校正回声强度 (AIIc % )、主动脉内膜 中膜厚度 (IMT)、主动脉收缩期直径 (Ds)、收缩期主动脉峰值流速 (Vp) ,并同期行血脂检测 ,于实验设定的时相点宰杀动物 ,获取主动脉标本 ,进行病理组织学、超微结构及免疫组化检测。结果　AS组主动脉AIIc %值随实验时间延长而显著增高 (P <0 .0 1)。IMT测值增大 ;Ds增大 ;Vp增快 ;组织学及超微结构观察发现AS组主动脉内膜平滑肌细胞明显增殖及大量弹力纤维形成 ;免疫组化检测结果显示AS组主动脉内中膜蛋白表达随实验时间延长而逐渐增强。结论　超声技术有助于评价主动脉粥样硬化 ,AS组主动脉内中膜AIIc %值增大的超微基础在于血管平滑肌细胞的明显增殖及大量弹力纤维的形成。     

高脂饲料加球囊扩张动脉粥样硬化兔腹主动脉模型的建立

目的 建立高脂饲料加球囊扩张动脉粥样硬化兔腹主动脉模型。方法 将30只新西兰大耳白兔随机分为高脂饲料和普通饲料两组喂养,每组15只,2周后,用相同方法损伤兔腹主动脉血管内皮细胞,定期测量体质和血脂类指标,18周处死动物,观察腹主动脉形态结构。结果 高脂饲料兔血脂类指标升高,血管内壁脂质沉积,镜下见内皮细胞脱落缺失,多层泡沫细胞堆积,平滑肌细胞减少或增生,弹力蛋白和胶原糖蛋白基质成分增多等改变。结论 动脉粥样硬化兔腹主动脉模型建立成功。     

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.     

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.     

Molecular characterization of virulence and antimicrobial resistance profile of Shigella species isolated from children with moderate to severe diarrhea in northeastern Brazil

Molecular characterization of virulence and antimicrobial resistance profiles were determined for Shigella species isolated from children with diarrhea in Fortaleza, Brazil. Fecal specimens were collected along with socioeconomic and clinical data from children with moderate to severe diarrhea requiring emergency care. Shigella spp. were isolated by standard microbiological techniques, and we developed 4 multiplex polymerase chain reaction assays to detect 16 virulence-related genes (VRGs). Antimicrobial susceptibility tests were performed using disk diffusion assays. S. flexneri and S. sonnei were the predominant serogroups. S. flexneri was associated with low monthly incomes; more severe disease; higher number of VRGs; and presence of pic, set, and sepA genes. The SepA gene was associated with more intense abdominal pain. S. flexneri was correlated with resistance to ampicillin and chloramphenicol, whereas S. sonnei was associated with resistance to azithromycin. Strains harboring higher numbers of VRGs were associated with resistance to more antimicrobials. We highlight the correlation between presence of S. flexneri and sepA, and increased virulence and suggest a link to socioeconomic change in northeastern Brazil. Additionally, antimicrobial resistance was associated with serogroup specificity in Shigella spp. and increased bacterial VRGs.     

护理干预对面部中重度寻常型痤疮的临床疗效影响分析

目的研究护理干预对面部中重度寻常型痤疮的临床疗效影响。方法选取本院在2014年4月~2016年7月诊治的136例面部中重度寻常型痤疮患者,随机分为研究组与对照组,每组68例;所有患者均依据其情况给予对应的治疗,其中对照组在治疗期间给予常规护理,研究组在对照组的基础上再给予综合性护理干预,比较两组的治疗效果及护理满意度情况等。结果患者在接受治疗和护理后,研究组中度与重度患者的治疗效果较对照组均明显提高(P0.05),研究组护理满意度较对照组明显增高(P0.05)。结论对面部中重度寻常型痤疮患者在其治疗期间给予综合性护理干预,具有良好的效果。