衍射增强成像(DEI)动物实验研究

目的通过动物样品的衍射增强成像(DEI),获得衬度及分辨率,并与常规吸收成像比较,对DEI方法进行分析和评价。方法在北京高能物理研究所同步辐射装置(BSRF)形貌站(4W1A束线)上,取大鼠脏器在摇摆曲线上进行扫描,并与常规吸收像进行比较,通过放大法获得分辨率。结果大鼠的肝脏、肾脏样本的DEI均显示较好的衬度和分辨率,并且扫描位置对图像显示具有较大影响。结论DEI从相位衬度角度进行成像,是一种有望开发运用于临床的先进成像技术。     

同步辐射技术应用于冠状动脉成像的实验初探

目的比较衍射增强成像（DEI）和单色光成像两种方法冠状动脉成像效果,评价同步辐射方法在冠状动脉成像上的意义。方法DEI装置及白光成像装置下,分别对大鼠心脏进行成像,在DEI成像时,采用离体心脏样品;在单色光成像时,采用活体大鼠,并静注60%碘造影剂1ml,迅速采集图像,以图像衬度和空间分辨率作为评价指标。结果两种方法均能显示大鼠的冠状动脉。虽然DEI不用造影剂,从成像效果上来说稍差于单色光技术效果,但两种成像方法获得的图像没有显著性差异。结论DEI用于冠状动脉成像是可行的,但受成像条件和方法的限制,同步辐射的优良特性尚未得到充分利用。     

磁共振扩散张量加权成像显示正常和病变肾脏的超微结构变化

背景:磁共振弥散张最可对每个体素水分子扩散的各向异性作出准确的检测.利用扩散张量成像评价肾脏及其病变内水分子运动特征,可反映出肾组织超微结构的变化,有利于病变的早期诊断.目的:验证磁共振扩散张量成像对正常肾脏和肾脏病变的临床诊断价值.方法;选择健康对照组12例和24例肾脏病变患者行肾脏扩散张量成像检查,肾脏病变患者中肾癌7例,肾囊肿7例,肾积水10例.观察肾脏皮质、髓质以及病灶表观扩散系数,分数各向异性的变化,并行髓质纤维束成像.结果与结论:正常肾脏中,肾皮质的表观扩散系数显著高于肾髓质(P=0.003),而肾髓质的分数各向异性显著高于肾皮质(P<0.05).肾癌表观扩散系数低于正常肾皮质、髓质(P<0.05),瘤体内分数各向异性显著低于正常肾髓质(P<0.05).肾囊肿表观扩散系数显著高于正常肾皮质、髓质(P<0.05),分数各向异性显著低于肾皮质和髓质(P<0.05).扩散张量纤维束示踪图可重建出肾髓质纤维束的形态,从而反映出肾小管和集合管的结构变化.提示扩散张量成像能显示正常肾脏和肾脏病变的超微结构变化,可用于肾脏病变的早期诊断和病情监控.     

同步辐射装置(BSRF)上的衍射增强医学成像实验

目的：利用衍射增强成像（DEI）技术成像机制的特异性，进行医学样品的成像研究，并进行分析评价。方法：使用衍射增强成像（DEI）技术对肝、肾样本进行成像，通过显微放大法获得图像分辨率，并对摇摆曲线上的不同位置成像结果进行分析，与病理和常规吸收像图像进行比较。结果：获得的成像具有较高的分辨率、可以显示更多的微细结构，摇摆曲线上的不同位置对成像具有较大的影响。结论：DEI对样品，尤其是弱吸收组织（软组织）显示具有较强的特异性，可望在临床上具有广阔的应用前景。     

衍射增强技术应用于医学成像的实验研究

目的本实验通过各类样品的DEI成像，获得衬度及分辨率，并与常规吸收成像比较，对衍射增强成像（DEI）方法进行分析和评价。方法在北京高能物理研究所同步辐射装置（BSRF）形貌站（4W1A束线）上，取人及动物脏器在摇摆曲线上进行扫描，并与常规吸收像进行比较，通过显微放大法获得分辨率。结果不同组织之间存在不同的衍射增强，DEI均显示较好的衬度和分辨率，图像分辨率达到微米级，并且扫描位置对图像显示具有较大影响。结论DEI从相位衬度角度进行成像，极大地改进了成像质量，理论上来说是安全的，有望运用于临床。     

比较同步辐射衍射增强与同轴技术小鼠肾脏成像

目的 通过评价同步辐射相位衬度成像技术在小鼠肾脏微细结构的成像过程,比较同轴成像技术(IOXI)与衍射增强成像(DEI)的差异,探索相位成像技术的应用价值。方法 在北京同步辐射装置(BSRF)形貌站4W1A和上海光源(SSRF)成像线站BL13W上,分别对小鼠肾脏进行成像,以组织衬度与空间分辨力作为评价指标。结果 肾脏微细结构在IOXI与DEI中均得以显示,尤其是IOXI可显示肾小球。通过显微放大法获得的图像空间分辨力达10 μm。结论 包括IOXI与DEI在内的相位衬度成像技术在软组织及血管结构的显示中均具有较高的应用价值。IOXI由于获得成像信息更多,且光路较为简单、图像可直接获得,在生物医学应用研究中的价值可能更高。     

同步辐射类同轴技术应用于肾脏成像的实验研究

目的 应用同步辐射光源的相干性,进行肾脏组织的类同轴成像研究,旨在评价相位衬度成像技术在软组织成像方面的意义.方法 在北京同步辐射装置形貌站4W1A束线上,取经过4%甲醛溶液固定后的人体肾脏组织样品,置于类同轴光路的样品架上进行成像,以空间分辨率和组织衬度作为评价标准.结果 在样品与成像板距离Z为150 mm时获得的肾脏成像,具有较高的组织衬度,包括肾小囊在内的结构均能较好显示,通过显微放大法获得的空间分辨率达到30 μm.结论 类同轴技术能较好显示肾脏的微细解剖结构,对于以轻元素为主的脏器成像有较好的应用价值.     

离体生物样本无对比剂血管成像:硬X线同轴轮廓相衬成像术的实验研究

目的 X线相衬成像能够在无对比剂和降低曝光量的情况下观察生物组织尤其是软组织的内部结构.该实验利用同步辐射相干X线,根据同轴轮廓成像原理,在无对比剂的情况下,观察新西兰大白兔和人的离体肝组织标本内部的血管结构.方法所有样品经10%甲醛溶液固定,并切成6 mm厚,10 mm×10 mm大小备用.成像胶片为富士工业胶片(Fuji-IX80).实验是在北京同步辐射实验室4W1A光束上进行的,实验装置类似于全息成像,最大光斑为20 mm×10 mm,光子能量为8 keV.改变样品和胶片的距离,以获得最佳的成像质量.结果兔肝标本的血管树得到清晰显示,人肝硬化标本的扭曲的异常血管也得到清晰显示.显示的最小的血管直径小于20 μm.结论在第一代同步辐射上,在无对比剂的情况下,肝脏样本内部的血管结构可以通过X线同轴轮廓成像的方法得到显示.     

兔股骨头软骨缺损同步辐射X线相衬成像研究

目的采用同步辐射X线相衬成像技术进行兔股骨头软骨组织缺损的观察.方法取新西兰大白兔双侧股骨头,一侧制成软骨缺损,对侧股骨头未缺损作为对照.以同步辐射宽带光对股骨头进行类同轴全息相衬成像.所有标本行普通X线成像以对比观察.结果同步辐射相衬X线成像技术可见清晰的50 μm左右软骨微缺损.结论同步辐射相衬X线成像技术可检测到普通X线成像技术无法检测到的软骨微缺损,并可进一步分析病变的细微结构.     

离体生物软组织同步辐射相衬CT成像

目的 探讨同步辐射相衬CT对离体生物软组织成像的可行性。方法 将手术切除人贲门标本3块、食管及食管癌标本各2块及自尸体标本提取的大脑中动脉组织2块固定并自然干燥,之后行同步辐射相衬CT成像,观察成像显示的软组织结构,并与病理结果进行对照。结果 同步辐射相衬CT图像清晰显示正常贲门及食管壁3层结构,即黏膜层、黏膜下层及肌层,黏膜面光整;在食管癌标本则显示癌组织浸润食管壁;对大脑中动脉组织可清晰显示脑动脉管壁及血管腔内状况。结论 同步辐射相衬CT成像能清晰显示离体生物软组织的细微结构。     

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.     

Systematic Reviews Published in the January 2011 Issue of The Cochrane Library

ABSTRACT

The Cochrane Library of Systematic Reviews is published quarterly as a DVD and monthly online. The January 2011 issue (first quarterly DVD for 2011) contains 4515 complete reviews, 1985 protocols for reviews in production, and 13,521 one-page summaries of systematic reviews published in the general medical literature. In addition, there are citations of 641,000 randomized controlled trials, and 14,018 cited papers in the Cochrane methodology register. The health technology assessment database contains over 9300 citations. One hundred and seven new reviews have been published in the last 3 months, of which five have potential relevance for practitioners in pain and palliative medicine.     

Interprofessional approaches to creating safe,high quality health care

Three supplementary perspectives are presented arguing that interprofessional collaboration is both necessary and desirable. Nonetheless, there are often too many serious intra-professional barriers and obstacles to interprofessional collaboration to make it successful. Some of these barriers, it is argued and illustrated, are found in the multiple ways in which professional identity is tacitly acquired and embodied in the practitioners' habitual, everyday practice. The paper then explores ways in which reflection, especially Second order reflection, can help to elucidate and overcome these obstacles, as well as increasing professional adaptability and competence.     

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.     

Prise en charge des entorses externes de cheville : étude clinique préliminaire sur l’efficacité du dispositif Myolux™

Ankle sprains are the most common injury of the musculoskeletal system and are associated with significant societal and economic impacts. It has been proven that classical therapeutic strategies may not be effective in preventing recurrent injuries: the recurrence rates reported in the literature can reach 73%. In order to provide an effective rehabilitation solution, a destabilizing orthosis was developed. This device is equipped with a mechanical articulator reproducing the subtalar mechanics and placed under the heel. In this paper, we present the main results of a preliminary clinical study conducted between 2004 and 2007. All subjects included in this study were treated with the abovementioned orthosis during 10 rehabilitation sessions of 30 minutes each. Data show a relatively low recurrence rate of 12% for the overall population. Moreover, it's of primary importance to note that this satisfactory ratio is largely reduced (3% of recurrence rate) for the 29 patients who performed one training session per month after the 10th initial rehabilitation sessions. Hence, the destabilizing orthosis appears to be an effective solution to prevent recurrent ankle sprains. However, joint protection requires long-term and regular training sessions. This result has motivated the development of a similar device allowing patients to perform training sessions at home. Finally, data obtained in this study are promising awaiting the final results of the comparative, multicentric and independent clinical trials currently managed by the Hospices Civils de Lyon.     

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.