经胸超声心动图代替经食道超声心动图引导房间隔缺损封堵术

目的：研究经胸超声心动图(TTE)代替经食道超声心动图(TEE)引导Amplatzer房间隔缺损(ASD)封堵器经导管治疗ASD。方法：64例有外科手术适应症的Ⅱ孔型ASD患者行TTE检查，如果可清楚观察ASD及其周边残存房间隔、周围功能性结构状况，能明确判断适合封堵即可选择TTE引导封堵。否则进行TEE检查，符合封堵条件者采用TEE引导。TTE引导时，心尖四腔切面观察封堵器呈规整‘00’形，大动脉短轴切面呈规整‘00’形或‘Y’形，剑下两房切面呈规整‘吕’字形；TEE引导时，观察封堵器腰部卡于房缺处、两伞平行地夹于房间隔两侧。同时超声观察到封堵器位置稳定，无残余分流，不影响周围结构功能，封堵成功。结果：5例封堵失败，其中TEE3例TTE2例。TEE成功引导26例封堵器置入，TTE33例。4例患者封堵2次，第2次住院封堵3例成功，TTE和TEE各引导2例。TTE随访，术后24小时每组各有1例患者少量残余分流(分流束宽≤2mm)，3个月时1例TTE引导的患者尚有少量残余分流。结论：大部分适合封堵的Ⅱ孔型ASD患者，TTE能清楚观察ASD及其周边残存房间隔状况、ASD边缘至周围功能性结构距离，可以代替TEE筛选患者、引导Amplatzer ASD封堵器置入。     

超声心动图在Ⅱ孔型房间隔缺损Amplatzer封堵治疗术中的应用

目的探讨超声心动图在筛选Ⅱ孔型房间隔缺损（ASD）病例并引导Amplatzer封堵伞介入方法关闭ASD中的应用价值。方法应用经食管超声心动图（TEE）按Amplatzer封堵法适应证条件筛选7例Ⅱ孔型ASD,经胸超声心动图（TTE）及X线引导进行Amplatzer封堵术。结果1例患者因ASD最大伸展径大于34mm,无相应的封堵伞而放弃封堵术,另1例患者因ASD缺损口距右房顶距离小于3mm,置入Amplatzer封堵伞未能封堵成功,放弃手术治疗,余5例成功进行了Amplatzer封堵术。所有病例TEE测量的ASD直径显著小于ASD最大伸展径［（17.2±1.9）mmvs（26.8±1.3）mm］,5例成功病例术后即刻、24h、1个月、3个月行TTE检查,术后无残余分流,术中、术后无并发症。结论超声心动图在Ⅱ孔型房间隔缺损介入治疗中占有极为重要、不可替代的地位。     

超声心动图在房间隔、室间隔缺损和动脉导管未闭Amplatzer封堵术中的应用研究

目的探讨超声心动图在Amplatzer封堵器封堵房间隔缺损(ASD)、室间隔缺损(VSD)及动脉导管未闭(PDA)中的应用价值.方法应用经胸超声心动图(TTE)或/和经食管超声心动图(TEE)对21例ASD、9例VSD和12例PDA患者行经导管Amplatzer封堵术治疗.结果41例患者Amplatzer封堵术成功,术中及术后均无并发症,1例巨大PDA合并肺动脉高压近期存在少量残余分流.结论超声心动图对于Amplatzer封堵ASD、VSD、PDA术前病例选择、术中指导监测、选择封堵器型号与术后疗效评价及随访均有重要价值.     

超声心动图在房间隔缺损封堵术中的应用

目的 评价超声心动图在房间隔缺损（ASD）封堵术中的应用价值。方法 应用经胸超声心动图（TTE）和／或经食道超声心动图（TEE），按ASD封堵适应症筛选32例ASD患者，经导管在X线引导下进行封堵，术中超声心动图实时监测，术后即刻、1、3、6、12、24个月超声心动图随访。结果 1例患者因ASD残端过薄且软，无法支撑封堵器而放弃封堵术，余31例（96．88％）患者封堵成功。26例（83．87％）术中超声显示即刻过隔血流束消失，5例（16．13％）存在微量残余分流，随访至6个月后，残余分流全部消失。所有病例均未出现其他并发症。结论 超声心动图在ASD封堵术中，对术前筛选病例、术中实时监测、术后定期随访发挥不可替代的作用。     

超声在房间隔膨出瘤并继发孔型房间隔缺损封堵术中的应用

目的 探讨超声心动图在房间隔膨出瘤（ASA）并发继发孔型房间隔缺损（ASD）封堵治疗中的应用价值。方法 应用经食管超声心动图（TEE）或经胸超声心动图（TTE）诊断ASA并发ASD17例，所有患者均在X线和术中TTE监测下行封堵治疗，术后TTE跟踪复查评价其疗效。结果 17例患者封堵器置人均获成功，共放置24个封堵器。封堵器选择的大小与术前判断大小相关性好（r=0．91，P〈0．001）。术后即刻显示17例患者21个封堵器处穿隔血流消失，有3例患者3个封堵器处仍有微量残余分流，术后1个月至3年复查1例有微量分流。结论 ASA并发ASD的患者可行封堵治疗且疗效确切，而超声心动图在病例选择、术中引导等方面有其特殊性，应引起超声医生和临床医生的重视。     

经食管超声心动图引导经胸微创封堵术治疗房间隔缺损的应用价值

目的探讨经食管超声心动图(TEE)在引导经胸微创封堵术治疗中央型房间隔缺损(ASD)中的应用价值。方法选取单纯ASD患者83例,所有患者均应用经胸超声心动图筛选适宜行经胸微创封堵术。术中先应用TEE测量ASD最大直径和房间隔长度,观察ASD形态及其与上下腔静脉的关系,确定合适的Amplatzer ASD封堵器号数,再经TEE引导下监测封堵,即刻观察手术效果。术后24 h和出院前经胸超声复查确定疗效。结果83例患者ASD最大直径4~26 mm,平均(16.76±1.21)mm;ASD最大直径与封堵器大小相关性良好(r=0.936,P0.01)。TEE引导房间隔穿刺、输送鞘管放置及封堵器输送释放,83例患者中除4例封堵失败改为体外循环下外科手术治疗外,余79例均成功完成经胸微创封堵术,手术成功率95.18%。出院前经胸超声复查仅1例有少量残余分流。结论 TEE能准确评估ASD形态及大小并选择合适封堵器,引导房间隔穿刺、封堵器输送及成功释放,即刻评价封堵器位置和残余分流,该手术方法创伤小、无辐射,临床应用价值高。     

心外科房间隔缺损封堵术中经食管超声心动图的应用价值

目的评价经食管超声心动图（TEE）监测房间隔缺损封堵术的临床价值。方法手术前应用经胸超声心动图（TTE）及TEE筛选符合条件的100例单纯房间隔缺损（ASD）患者行封堵术;手术中TEE监测整个封堵过程和引导封堵伞的放置;手术后评价封堵效果、残余分流或并发症等。结果 100例患者均应用TTE和TEE确诊,导引和监测成功闭合房间隔缺损。技术成功96例,成功率96%;4例失败,失败率4%。手术后复查无1例残余分流,3例胸腔积液。经胸超声心动图与TEE诊断结果完全一致率40%,TEE诊断对手术前TTE诊断做出补充或修正诊断的有60例（60%）。结论 TEE对选择适合行封堵术者、选择封堵器大小、指导封堵器的释放、以及疗效评价均具有重要的作用。     

超声心动图在小儿及疑难房间隔缺损介入治疗病例中的应用探讨（附126例报告）

目的：评价超声心动图在继发孔型房间隔缺损（ASD）介入封堵治疗中的应用价值。方法2008年9月～2012年12月,126例继发型房间隔缺损患儿,其中男38例,女88例,年龄2.3～17.0岁,平均6.7±3.5岁。单一ASD 117例,多发性ASD 9例。其中1例合并肺动脉瓣狭窄（PS）,3例合并房间隔膨出瘤（ASA）。126例患儿均行经胸超声心动图（TTE）检查,少数肥胖患儿行经食管超声心动图（TEE）检查,根据检查结果选择封堵器型号,术中用TTE或TEE引导封堵器释放。术后采用TTE随访。结果124例患儿其中含边缘不足的7例疑难病例,应用进口或国产封堵器均成功封堵,成功率98.4%。经TTE或TEE测量ASD最大直径3.3～26.0mm,平均16.5±3.4mm。所选封堵器直径6.0～30.0mm,平均19.0±4.0mm。7例多发性ASD选用1枚封堵器,1例选用2枚封堵器获得成功。1例合并PS者同时完成介入治疗。124例患儿术后TTE随访发现,2例存在微量残余分流,并于1个月后自愈。结论超声心动图在小儿ASD介入适应症选择及介入过程中引导、术后随访中的作用仍不可替代。     

彩色多普勒超声心动图评价房间隔缺损封堵术患者的心功能改变

目的：评价房间隔缺损(ASD)患在经导管Amplatzer伞封堵治疗术后的疗效及随访中左、右心功能及血流动力学的变化。方法：26例继发孔型房间隔缺损患术前经食管超声心动图(TEE)检查示ASD直径平均为20.49mm士6.27mm(7.5mm～34mm)。所有病例均在透视及经胸和／或经食管超声心动图(TEE)监视下经导管置入Amplatzer封堵器封堵ASD。在经胸或经食管超声心动图监测下行Amplatzer闭合器封堵房间隔缺损。术后24～48小时、1个月、3个月及1年分别行经胸超声心动图(TTE)检查，测量左、右室及右房大小、肺动脉内径及肺动脉压、左室每搏量及左室射血分数、左室偏心率，评价治疗效果。结果：ASD Amplatzer伞封堵术后，左室内径增大，左室每搏量、左室射血分数增高。右室、右房及肺动脉内径缩小，肺动脉压明显下降，92.3％恢复正常，左室偏心率变小，心脏重构在随访中持续逆转，心脏血流动力学明显改变。结论：ASD封堵治疗既减轻了右心负荷，也改善了左室收缩功能，并且逆转了心脏重构，血流动力学明显改善，术后三月时大多数患可恢复到正常水平。     

超声心动图在多孔的2型房间隔缺损封堵术中的应用价值

目的 探讨超声心动图在多孔的2型房间隔缺损（ASD）封堵治疗中的应用价值。 方法 应用经食管超声心动图（TEE）或经胸超声心动图（TTE）诊断多孔的2型ASD23例，所有患者均在X-线和术中TTE监测下行封堵治疗，术后TTE跟踪复查评价其疗效。 结果23例患者封堵器置入均获成功，共放置38个封堵器。封堵器选择的大小与术前判断大小相关性非常好，相关系数r=0．9，P〈0．001。术后即刻显示18例患者33个封堵器处穿隔血流消失，有5例患者5个封堵器处仍有微量残余分流，术后1个月～3年复查2例有微量分流。 结论 多孔的2型ASD患者可行封堵治疗且疗效确切，但超声心动图对病例选择、术中引导等方面有其特殊性，应引起超声医师和临床医师的高度重视。     

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.