应变率成像评价2型糖尿病患者左室局部功能早期损害的临床研究

目的探讨应变率成像技术评价2型糖尿病患者左室局部功能早期损害的临床价值。方法选取左室构型正常的2型糖尿病患者（糖尿病组）20例,健康者20例为对照组。应用常规超声心动图测量二尖瓣口舒张期血流E峰、A峰,计算E／A,应变率成像技术测量左室长轴方向18节段的心肌收缩期峰值应变率（SRs）、舒张早期峰值应变率（SRe）和舒张晚期峰值应变率（SRa）,并计算SRe／SRa,比较两组各参数的差异。结果糖尿病组E峰、E／A低于对照组,A峰高于对照组,糖尿病组各节段室壁运动收缩期SRs低于对照组,糖尿病组舒张期SRe、SRa和SRe／SRa均低于对照组（均P〈0．05）。结论应变率成像技术可以定量评价糖尿病患者的左室局部心肌应变率异常,SRs可以作为评价左室局部收缩功能的有效指标,SRe、SRa和SRe／SRa可以作为评价左室局部舒张功能的有效指标。     

心肌背向散射积分参数评价乳腺癌术后患者表阿霉素心脏毒性的价值

目的应用超声背向散射积分（IBS）技术研究表阿霉素治疗乳腺癌的心脏毒性的背向散射参数的变化特征，探讨其临床应用价值。方法133例乳腺癌术后患者分为3组：A组45例，给予表阿霉素总剂量180～240mg／m^2；B组48例，给予表阿霉素总剂量≥360mg／m^2；C组40例，为对照组，未予化疗。对3组患者心脏进行常规超声测量及IBS参数测定。结果A组与C组间常规超声参数及IBS参数无显著性差异（P〉0．05）。A组与B组间常规超声参数无显著性差异（P〉0．05），B组与C组常规超声参数（E／A除外）无显著性差异（P〉0．05）。B组参数E／A、CVIB显著减低，IBS％显著升高，与A组、C组有显著性差异（P〈0．05、P〈0．01）。结论心肌背向散射技术可作为早期评价乳腺癌术后患者表阿霉素心脏毒性的手段之一。     

应变率显像对缺血心肌收缩和舒张功能评价的研究

目的通过应变率显像评价冠心病患者缺血心肌的局部收缩和舒张功能。方法30例冠心病患者,测定缺血心肌的应变率数值（SR）,包括收缩期峰值（SRs）、舒张早期峰值（SRe）和舒张晚期峰值（SRa）,并测量左室射血分数（EF）;正常组选取30人作为对照。结果冠心病组节段心肌SRs和SRe均低于正常组相应节段的测值（P〈0．05）,而两组间的EF差异无统计学意义。结论心肌应变率显像是一项实用的诊断心肌缺血的新方法。     

定量组织速度成像评价乳腺癌患者表阿霉素心脏毒性左心室功能的变化

目的探讨定量组织速度成像（QTVI）技术评价乳腺癌患者表阿霉素化疗心脏毒性左心室功能变化的价值。 方法133例乳腺癌术后患者分为3组：A组45例，给予表阿霉素总剂量180～240mg／m^2；B组18例，给予表阿霉素总剂量≥360mg／m^2；C组40例，为对照组，未给予化疗。对3组患者心脏进行常规超声测量及心肌各节段QTVI参数测定。 结果A组与C组间常规超声参数及QTVI各参数均无显著性差异（P＞0．05）；B组与C组间常规超声参数（E／A除外）无显著性差异（P＞0.05），B组参数E／A显著减低，与C组有显著性差异（P＜0．01）；Va明显增高与A组、C组有显著性差异（P＜0．05）。B组Vs无明显变化（P＞0．05），B组参数Ve、Ve／Va显著减低，与A组、C组有显著性差异（P＜0．01）。 结论QTVI技术可以准确评价乳腺癌患者表阿霉索心脏毒性左心室功能的变化。     

应变及应变率评价系统性红斑狼疮患者的左室功能

目的 应用应变(ε)及应变率(SR)技术评价系统性红斑狼疮(SLE)患者的左室收缩和舒张功能.方法 20例临床确诊的SLE患者(病例组)与20例健康人(对照组),获取左室各壁基底段和中间段的ε和SR曲线,测量收缩期峰值应变率(SRs),舒张早期峰值应变率(SRe),舒张晚期峰值应变率(SRa),收缩期峰值应变(ε).同时测量左室射血分数(EF)及二尖瓣口血流峰值速度E,A,计算E/A值.结果 SLE组各节段的SRs,SRe,ε均明显低于对照组相应节段测值(P＜0.05),大部分SRa明显低于对照组相应节段测值,而两组的EF值和E/A值无显著性差异(P＞0.05).结论 某些SLE患者心肌有明显受损,应用ε及SR技术可以检测SLE患者心肌受损.     

定量组织速度成像评价左乳腺癌患者放疗左心室功能的变化

目的探讨定量组织速度成像（QTVI）技术评价左乳腺癌术后患者放疗左心室功能的变化的价值。 方法35例左乳腺癌术后患者按照放疗进程分为A组（对照组，35例）：放疗前；B组（35例）：放疗时间3周、累积剂量30Gy；C组（35例）：放疗结束，时间5周，累积剂量50Gy。对3组患者心脏进行常规超声测量及心肌各节段QTVI参数测定。 结果C组左室舒张功能（E／A）较A组减低差异具有显著性意义（P＜0．01）；B组常规超声各指标与A组比较差异无显著性意义（P＞0．05）。B组心肌各节段QTVI参数与A组的比较无显著性差异（P＞0．05）。C组二尖瓣环前壁、前间隔的舒张晚期峰值速度（Va）明显增高，与A组比较有显著性差异（P＜0．01），舒张早期峰值速度（Ve）、Ve／Va与A组的比较明显减低（P＜0．01），而C组收缩期峰值速度（Vs）与A组的比较无显著性差异（P＞0．05）；C组二尖瓣环下壁、后壁各指标与A组的比较均无显著性差异（P＞0．05）。 结论QTVI技术可以准确评价左乳腺癌术后放疗患者早期左心室功能的变化。     

应变率成像评价高通量血液透析对尿毒症患者左室局部功能的影响

目的探讨高通量血液透析（HFHD）对尿毒症患者左室局部舒缩功能的影响。方法选取30例尿毒症患者,分别于HFHD治疗前及治疗后6个月应变率成像测量其左室局部应变率参数：室间隔、侧壁、下壁、前壁的基底段及中间段的收缩期峰值应变率（SRs）、舒张早期应变率（SRe）、舒张晚期应变率（SRa）,计算SRe／SRa。结果治疗后各室壁节段的SRs、SRe及SRe／SRa均较HFHD治疗前增高,SRa较治疗前减低,差异均有统计学意义（P〈0．05）。结论HFHD能够改善尿毒症患者左室局部舒缩功能,应变率成像可敏感反映HFHD治疗前后左室局部舒缩功能的变化。     

应变率显像评价2型糖尿病患者左室功能的临床研究

目的应用组织多普勒显像检测糖尿病患者左室心肌组织运动速度及应变率特征,评价左室舒张功能的改变,为早期诊断及治疗糖尿病心肌病变提供依据。方法2型糖尿病患者52例及正常人20例。A组：30例,糖尿病无微血管病变,B组：22例,糖尿病合并微血管病变。C组：20例,健康人对照。超声心动图检查测定左室收缩功能、舒张功能及左室心肌质量指数（LVMI）。定量组织速度成像（QTVI）测定心肌组织运动速度参数;应变率显像（SRI）测定心肌组织应变与应变率参数。结果与对照组及A组相比,B组收缩期应变率峰值（SRs）及舒张早期应变率峰值（SRe）,舒张早晚期组织速度比值PVe/PVa降低（P〈0.05）,各组心房收缩期应变率峰值（SRa）和收缩期速度（PVs）无显著性差异。结论应变率显像技术可评价2型糖尿病患者的左室心肌收缩、舒张功能。     

应变率显像结合定量组织速度显像评价冠心病患者支架置入术前后左室功能

目的探讨应变率显像（SRI）技术结合定量组织速度显像（QTVI）技术在评价冠心病患者冠状动脉支架置入术前后左室功能的临床价值。方法28例冠状动脉中重度狭窄的冠心病患者,分别于支架置入术前、术后1周和1个月行超声心动图检查：QTVI测量二尖瓣环收缩期、舒张早期、舒张晚期峰值运动速度Sa、Ea和Aa,SRI测量各狭窄冠脉供血节段（缺血节段）收缩期、舒张早期、舒张晚期心肌长轴峰值应变率SRs、SRe和SRa;计算Ea／Aa和SRe／SRa;比较分析支架置入前后各检测指标。结果①与术前比较,术后1周Ea／Aa显著增高（P〈0．01）;与术前及术后1周比较,术后1个月sa、Ea和Ea／Aa均显著增高（P〈0．05或〈0．01）。②与术前比较,术后1周SRe、SRe／SRa显著增高（P〈0．01）,与术前及术后1周比较,术后1个月SRs、SRe、SRe／SRa均显著增高（P〈0．05或〈0．01）。⑧术前、术后1周、术后1个月Ea／Aa与SRe／SRa均呈显著正相关（P〈0．01）。结论SRI结合QTVI可对支架置入术前后心脏局部和整体功能作出全面客观的评价,从而为术前手术指征的确定及术后疗效的判定提供一个新思路。     

应变率成像技术评价胸部放疗部位与心脏早期损伤的关系

目的采用应变率成像技术（SRI）分析胸部放疗部位与心脏早期损伤的关系,评价其在心脏损伤方面的临床应用价值。方法60例接受胸部放疗的肿瘤患者分为A组（经前胸照射）和B组（经前胸、后背对穿照射）。放疗前后对两组分别进行常规超声心动图测量和SRI参数测定。结果放疗后与放疗前比较,A组左心室前壁、前间隔的收缩期最大应变率（SRs）、舒张早期最大应变率（SRe）明显减低（P〈0．01）;B组左心室前壁、前间隔、后壁的SRs、SRe减低（P〈0．05）;A组、B组左室舒张功能（E／A）减低（P〈0．01）;放疗后A组左心室前壁、前间隔的SRs、SRe较B组减低（P〈0．05）,B组后壁的SRs、SRe较A组明显减低（P〈0．01）。结论放射线直接照射部位心肌功能较易受到损伤,应变率成像技术可定量分析胸部放疗患者心脏的早期损伤。     

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.     

Guns and Knives in New Mexico: Patterns of Penetrating Trauma, 1978–1993

Objective: To identify patterns of nonfatal and fatal penetrating trauma among children and adults in New Mexico using ED and medical examiner data.
Methods: The authors retrospectively sampled in 5-year intervals all victims of penetrating trauma who presented to either the state Level-1 trauma center or the state medical examiner from a 16-year period (1978–1993). Rates of nonfatal and fatal firearm and stabbing injury were compared for children and adults.
Results: Rates of nonfatal injury were similar (firearm, 34.3 per 100,000 person-years; stabbing, 35.1). However, rates of fatal injury were significantly different (firearm, 21.9; stabbing, 2.7; relative risk: 8.2; 95% confidence interval: 5.4, 12.5). From 1978 to 1993, nonfatal injury rates increased for children (p = 0.0043) and adults (p < 0.0001), while fatal penetrating injury remained constant. The increase in nonfatal injury in children resulted from increased firearm injury rates. In adults, both stabbing and firearm nonfatal injury rates increased.
Conclusions: Nonfatal injury data suggest that nonfatal violence has increased; fatal injury data suggest that violent death rates have remained constant. Injury patterns vary by age, mechanism of trauma, and data source. These results suggest that ED and medical examiner data differ and that both are needed to guide injury prevention programs.