二次谐波显像评价正常犬肝脏声学造影的实验研究

目的： 评价二次谐波显像在正常肝脏声学造影中的造影增强效果及动态变化规律,并与常规基波显像进行对比分析。方法： ６ 只健康杂种犬经外周静脉注射相同剂量的氟碳声学造影剂, 分别用二次谐波和基波显像扫描肝脏。结果： 声学造影后正常肝脏的灰阶影像有显著的视觉造影效果和视频密度定量值提高; 基波造影前后视频密度值分别为 ９３±１０３８ 和１０６±１２１９; 二次谐波造影前后视频密度值分别为９５±１１６７ 和１２８±１８４９。结论： 新型声学造影剂结合二次谐波显像技术可以明显增强正常肝脏的二维超声影像、反映肝脏血流灌注情况。二次谐波显像明显优于常规基波显像。     

肝脏VX2肿瘤声学造影-剂量与效应关系

目的： 探讨不同声学造影剂剂量在肝脏 ＶＸ２ 肿瘤显影中的增强效果及变化规律。方法： １３ 只患有ＶＸ２ 肝肿瘤的新西兰白兔分别经外周静脉注射氟碳声学造影剂０．０１、０．０２、０．０４ｍ ｌ／ｋｇ, 按常规连续显像和延迟显像方式然后用高频基波显像和二次谐波显像观察肿瘤造影效果。结果： 基波显像在０．０１、０．０２、０．０４ 剂量水平产生的视觉肿瘤显影评分显著低于二次谐波显像 （Ｐ＜ ０．０１）, 基波显像在０．０１、０．０２、０．０４ 剂量水平产生的肿瘤显影视频密度值分别为２３．２３±７．５４、４０．０２±１０．１８ 和４３．７８±１０．４, 二次谐波显像的对应值是６５．５５±１１．３３、８７．８３±１７．０３和１１２．１６±２３．３８ （Ｐ＜ ０．０１）。结论： 声学造影剂量－效应关系在二次谐波显像中变化敏感, 在基波显像中变化相对不敏感。     

微泡声学造影剂气体构成对二次谐波显像的作用

目的探讨二次谐波成像条件下改变微泡造影剂的气体构成是否能够增强经静脉注射后的心肌显像效果。方法对１０条开胸犬经静脉注射含有不同气体的声振右旋糖酐白蛋白微泡造影剂ＲＡ（空气,ｒｏｏｍａｉｒ）、ＳＦ６（六氟化硫,ｓｕｌｆｕｒｈｅｘａｆｌｕｏｒｉｄｅ）、ＦＸ系列（含有氟碳气体Ｃ３Ｆ８、Ｃ４Ｆ１０、Ｃ５Ｆ１２）。二次谐波显像条件下取左心室短轴切面观,观察心肌造影效果。结果含有氟碳气体的微泡造影剂经静脉注射后二次谐波显像下产生强烈的心肌显影,心肌声学密度分别为（１４．７２±２．７）ｄＢ（ＦＸ３３０）、（１４．３±２．４ｄＢ）（ＦＸ４３０）、（１３．７８±２．２４）ｄＢ（ＦＸ５３０）;氟硫气体仅存在轻微的心肌显像［（６．２４±１．５８）ｄＢ］,但心腔显影强烈［（２９．４８±６．０２）ｄＢ］,空气造影剂经静脉注射后几乎不产生心肌显影［（２．５３±０．７８）ｄＢ］,心腔内造影剂亦较弱［（１１．３±４．９６）ｄＢ］。结论不同气体构成的微泡声学造影剂二次谐波显像效果差异显著。氟碳气体声振右旋糖酐白蛋白是较好的经静脉声学造影剂。     

新型声学造影方法评价兔肾脏VX2肿瘤血流灌注的实验研究

目的　探索新型声学造影技术在评价肾脏ＶＸ２ 肿瘤血流灌注方面的诊断价值。方法　５ 只患有ＶＸ２肾肿瘤的新西兰白兔经耳缘静脉注射ＦＸ５３０ 声学造影剂,用二次谐波和基波显像观察兔肾造影效果,分析使用视觉评分和视频密度定量。结果　新型声学造影方法显著地增强了肾肿瘤的超声影像、实时显示了肿瘤异常血流灌注状态,即呈“充盈缺损”状负性显影。ＶＸ２ 肿瘤与肾皮质的视频密度灰阶差值从造影前的１６６ 提高到４５８３（ 基波）和８０１７（ 二次谐波） 。结论　新型声学造影技术可以反映肾脏ＶＸ２ 肿瘤的异常血流灌注,显著提高肿瘤影像清晰度。     

声学密度定量评价正常兔肝脏谐波显像声学造影的价值

目的：探讨声学密度定量评价间歇谐波显像在正常肝脏声学造影中的价值。方法：10只正常家兔经外周静脉注射自制的白蛋白氟碳声学造影剂，分别用间歇基波显像，间歇谐波显像观察肝脏，并用声学密度定量（AD）分析造影效果。结果：间歇基波显像及间歇谐波显像AD参数：峰值强度（PI），曲线下面积（AUC）造影后均较造影前有明显的增加，而平均渡越时间（MTT），降半时间（HT）造影后均较造影前有明显的降低，造影前后两种显像方式各参数间亦有显著性差异。结论：声学密度定量可作为评价肝脏声学造影血流灌注的定量指标。     

心肌声学造影与二次谐波技术

１．二次谐波显像的基本原理目前测定左、右室血流的方法是用Ｄｏｐｐｌｅｒ技术,而心肌内的血流由于量少（仅占心肌的６％）,血流速度很低,很难用Ｄｏｐｐｌｅｒ技术测出。一些研究用冠脉内注射造影剂与常规超声结合,也不能明确区分出正常心肌与缺血心肌〔１〕。为了区分血流与周围组织,现发明一种新的技术—Ｈａｒｍｏｎｉｃ成像技术〔１、２〕,使用新型声学造影剂静脉内注射和二次谐波技术相结合,经胸超声即可证实心肌灌注的情况。二次谐波显像又称谐波显像,其理论基于超声波与声学造影剂的微泡的相互作用。在声场交替声压的作用…     

灌注-延迟显像方法在兔肝脏VX2肿瘤声学造影中的价值

目的： 探讨灌注－延迟显像方法在肝脏ＶＸ２ 肿瘤声学造影中的增强效果及变化规律。方法： ９ 只患有ＶＸ２ 肝肿瘤的新西兰白兔经外周静脉注射氟碳声学造影剂, 按常规连续显像方法和灌注－延迟显像方法分别用高频二次谐波显像观察肿瘤造影效果。结果： 灌注－延迟显像产生的视觉肿瘤显影评分显著高于常规二次谐波显像 （Ｐ＜０．０１）, 灌注－延迟显像和常规显像的肿瘤显影视频密度值分别为１１８．３８±１８．４１ 和８７．８３±１７．０３ （Ｐ＜ ０．０１）。常规显像方法和灌注－延迟显像方法在对于 ５－１０ｍ ｍ 肿瘤结节的超声检出率分别为 ６３．６％ 和９０．９％ 。结论： 灌注－延迟显像方法在确保观察到肿瘤血管早期增强现象的同时, 可以显著提高ＶＸ２ 肿瘤声学造影的影像对比度和诊断敏感性。     

声学造影评价肾实质血流灌注的实验研究

目的自制的造影剂结合新型声学造影方法评估正常肾脏的血流灌注变化及造影增强效果。方法新西兰白兔20只,实验分为基波显像、谐波显像、间歇式显像,并在不同剂量水平观察。结果基波显像效果明显弱于二次谐波显像(P<0.01)。基波显像多为1级,二次谐波显像多为2~3级,间歇式谐波显像的效果最佳。肾髓质的造影灌注较皮质晚1~2s,且造影增强较肾皮质明显差。剂量0.05ml/kg时,二次谐波造影后的峰值视频密度差较基波显像高(142.83±13.70vs81.18±6.63,P<0.01),间歇式谐波显像视频密度值最高达170.74±3.72。造影峰值半降时间在间歇式显像延长(8.6±1.8)s vs(13.7±2.6)s,P<0.01。结论声学造影可以增强肾脏的二维超声影像,反映肾脏的血流灌注情况。     

间歇式谐波显像声学造影评价肾实质血流灌注

目的：评价间歇式谐波显像观察肾实质血流灌注声学造影的优越性。方法：自制的白蛋白包裹氟碳气体的造影剂对８只兔外周静脉造影。分别用基波显像、基波间歇显像、二次谐波显像、间歇式谐波显像四种成像方式观察造影效果。结果：间歇式谐波显像的视觉效果分级最高,视频密度值高达１６０．７４±３．７２,与其它组差异显著（Ｐ＜０．０１）,较基波显像延长造影峰值半降时间（１６．７±３．６ｓ,８．４±１．８ｓ）,差异显著（Ｐ＜０．０１）。结论：间歇式谐波显像能增强肾实质造影信号强度,延长造影时间,是一种较好的造影显像方法。     

二次谐波显像评价正常兔肾脏声学造影的实验研究

目的：评价二次谐波显像在正常兔肾脏声学造影中的造影增强效果，并与基波显像进行对比分析。方法：10只正常新西兰大白兔经耳缘静脉注入氟碳声学造影剂，分别用基波与二次谐波成像扫描肾脏 ，造影效果评价使用视觉评分和视频密度分析。结果：与基波相比，二次谐波成像显著提高了肾脏（主要为肾皮质）的造影效果。结论：二次谐波显像在肾脏造影中明显优于常规基波成像，它将进一步提高超声诊断肾脏疾病的水平。     

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.