酰胺质子转移成像的临床研究进展

酰胺质子转移(Amide Proton Transfer,APT)成像作为一种新型的磁共振成像方法,可以通过水信号变化来检测水中游离原蛋白、多肽酰胺质子和水质子的化学交换特征,从中反映组织中蛋白质和p H的变化。临床近年来已开展如脑肿瘤、多发性硬化、肝性脑病及子宫颈癌等方面的应用研究,是一种无辐射且无损伤的磁共振分子成像新技术。该研究对APT技术原理及其在临床上的应用现状进行综述,并对其在小儿腹部肿瘤应用前景进行展望。     

磁共振成像检查在直肠癌术前诊断中的应用

目的探讨磁共振成像技术用于直肠癌术前诊断的临床应用价值。方法选取我院2010年1月~2013年1月期间收治的直肠癌患者35例,应用磁共振成像技术进行检查,与术后病理证实结果进行对比分析。结果磁共振成像诊断肿瘤分期共29例诊断正确,诊断准确率为82.86%,肿瘤分期越高,诊断准确率越高,磁共振成像诊断周围脂肪侵润准确率为85.71%,周围器官以及骨盆侵润准确率94.29%,淋巴结转移准确率97.1 4%。结论磁共振成像技术可以比较准确地诊断肿瘤的肠壁浸润深度以及淋巴结的转移情况,对于术前诊断直肠癌及其分期具有较大的参考价值。     

浅谈肺部MRI成像新技术

MRI与CT比较的最直接优势为可进行多平面成像 ,由于肺的含气量高 ,质子密度较小 ,所以在磁共振成像中被认为不及X -CT。然后纵膈内血管、脂肪组织丰富 ,在磁共振成像中可获得良好的天然对比 ,是纵膈病变的首选影像学方法。随着MRI成像技术的不断发展 ,针对肺脏的MRI成像 ,解决了肺组织质子密度不足的问题。在传统的肺脏MR成像中 ,具有非常短的TE和单次激发快速SE序列已可以显示肺实质 ,为肺脏的MRI提供了一个基本平台。在其基本平台上的功能成像 ,更好的显示肺部图像 ,包括肺脏MRI的灌注成像、通气成像及通气 -灌注成像。1　肺脏…     

谈抑制磁共振图像运动伪影的几种方法

本文介绍了磁共振成像中的运动伪影产生的原因,以及梯度瞬间置零、快速成像、预期门迭、触发、自适应校正、空间预饱和等抑制伪影的几种方法,并加以比较。     

膝关节磁共振成像技术临床应用研究

目的:探讨膝关节磁共振扫描成像技术.方法:50例患者MR扫描序列包括斜矢状位PDW[、SET1WI;冠状位PDWI、SET1WI;横轴位FSET2WI.所有PDW[采用化学饱和法脂肪抑制技术.结果:本组病例中膝关节挫伤25例;20例半月板退变,其中3例伴半月板撕裂;韧带损伤5例.结论:磁共振扫描参数的优化组合和选择正确的扫描方法、恰当的线圈及应用脂肪抑制技术更有助于显示正常膝关节解剖结构及病变的定位和诊断.     

0.35T磁共振系统上心脏成像技术及其应用（上）

目的:探索低场磁共振成像系统上进行心脏成像的可行性及技术和方法.方法:将高场系统上的心脏成像序列和技术进行调整和优化,用于0.35T磁共振成像系统,进行心脏结构和功能的显示.结果:在硬件、软件优化设计的低场磁共振成像系统上获得的显示心脏结构和功能的图像,可满足临床诊断的需求.结论:在低场磁共振成像系统上进行心脏检查,包括冠状动脉成像和心肌灌注成像等高级应用,值得进一步探索和期待.     

磁共振弥散加权成像技术在脑梗死诊断中的应用

磁共振检查已从过去单一的观测生理、病理条件下的生物体解剖结构以及形态学上的变化,发展到研究生物体功能与活动机制,并进入到分子影像与功能性磁共振成像（fMRI）,而弥散加权磁共振成像技术（DWI）就是这其中之一,主要用于脑梗死的早期诊断。通过对磁共振弥散加权成像技术、DWI鉴别急性和非急性脑梗死的病理生理基础、DWI检查的时间价值的阐述,认为应用DWI区分急性和非急性脑梗死对临床治疗该疾病有着积极的意义,临床医师可以根据脑梗死的不同时期采取有针对性的治疗方案,回避不安全的治疗,避免不必要的具有风险性的治疗方法。     

MRI的运动和流动伪影的形成与抑制技术

磁共振成像时,运动和流动伪影常严重降低图像质量,二者产生的机制非常复杂。对运动和流动伪影的前处理抑制技术,包括改变磁共振成像参数、使用空间预饱和脉冲、抑制呼吸运动伪影的门控和触发等技术,以及抑制运动和流动伪影的磁共振成像序列的进展等进行描述,并简要介绍了磁共振运动和流动伪影的后处理矫正技术。     

磁共振磁敏感加权成像技术及其临床价值

目的：探讨磁共振磁敏感加权成像（SWI）的序列特点和临床价值。方法：回顾分析近期有关SWI临床应用的国内外相关文献。结果：SWI作为一种新型无创的对磁化率因素极为敏感的MRI检查技术,在许多疾病的诊断中发挥着重要作用。特别是在大脑血管性病变、外伤、脑肿瘤以及退行性神经病变等疾病的诊断中,其与传统MRI检查方法相比较具有独特的价值,同时在脑功能成像（fMRI）以及磁共振靶向成像方面有着较大的发展潜能。结论：SWI是一种对缺氧血、铁和钙等顺磁性物质具有极高敏感性的磁共振检查方法,在神经障碍性疾病领域得到了广泛使用。     

磁共振成像技术及其优越性

计算机磁共振成像技术是继断层扫描后出现的一项新兴技术,主要用于影像诊断,其成像技术原理是,在外磁场的作用下,基于物质内部不同结构环境中释放出的能量而得到的结构成像,图像清晰反映了物质的内部结构,有利于进行下一步的探究。目前,计算机磁共振成像技术不仅在化学、物理等领域展现出明显优势,也广泛运用于医学领域,提高了临床医学影像诊断水平,是辅助医师进行临床诊治的有效手段。该文对计算机磁共振成像技术的原理、使用及优越性分别进行综述,旨在为临床影像学诊断提供理论依据。     

Calcium intake in the elderly: validation of a dietary questionnaire

Epidemiological studies of calcium and osteoporosis have been hampered by the lack of a suitable tool for assessing calcium intake. This report describes a new frequency and amount questionnaire for measuring present and past calcium intake in the elderly. The validity of the questionnaire was tested against two commonly used standards of dietary assessment, five-day duplicate diets and seven-day weighed dietary inventories. The resulting correlation coefficients were, respectively, r = 0.76 and r = 0.69, while that for repeatability was r = 0.84. Furthermore, the questionnaire categorized subjects into thirds of the distribution of intake with almost no gross misclassification. It is suggested that the present findings may be extended to the majority of normal, healthy elderly subjects, implying wide application for the questionnaire in the assessment of calcium intake in the elderly.     

Self-reported health problems among Swedish miners one year after unemployment

Unemployment is considered to be a public health concern sincedeterioration in the health of the unemployed is often anticipated.However, for some groups, such as miners, unemployment mightimprove health due to a cessation of potentially harmful occupationalexposures. This study evaluates the health of 79 miners in oneSwedish iron-ore mine, and 226 age-matched controls from thegeneral population, during one year after the closure of themine. The participants received a questionnaire regarding medicalhistory and subjective symptoms at the beginning of the studyperiod, and after one year. Statistically significant negativeeffects on self-reported health attributable to unemploymentwere not found, although neuropsychiatric symptoms were morecommon among the unemployed miners. The miners reported a statisticallysignificant improvement in grip force (p=0.031). They had asignificantly higher prevalence of symptoms associated withmining related exposures when compared with the population controls;pain in the upper extremities [relative risk (RR)=2.27, 95%confidence interval (Cl)=1.44–3.59), back pain (RR=1.84;Cl=1.237–2.75), vasospastic disease of the fingers (RR=2.05;Cl=1.18–3.57) and obstructive respiratory symptoms (attacksof dyspnea and wheezing: RR=3.67; Cl=1.167–11.6).     

Excès de cas humains et animaux de tularémie en France au cours de l’hiver 2007–2008 : émergence ou phénomène isolé ?

Context

Tularemia is a zoonosis affecting humans and hares in France. We describe the results of surveillance in both species, in 2007 and 2008.

Methods

Human tularemia cases are mandatorily notifiable in France since 2003. In hares, surveillance relies on volunteer hunter associations in all districts of the country. Data from mandatory reports and volunteer surveillance in 2007/2008 were analyzed and compared with previous results.

Results

In 2007/2008, 144 cases were reported in humans and 117 cases in hares. This was a 100% increase compared to previous years. Human cases differed from those of previous years only by the frequency of contact with breeding animals. Human cases without any documented risk exposure were also more frequent.

Conclusion

An increase of tularemia cases occurred in 2007/2008 in both species. Complementary studies are needed to identify the species reservoir in France to understand the causes of this peak of cases.     

Occupational health hazards in mining: an overview

This review article outlines the physical, chemical, biological, ergonomic and psychosocial occupational health hazards of mining and associated metallurgical processes. Mining remains an important industrial sector in many parts of the world and although substantial progress has been made in the control of occupational health hazards, there remains room for further risk reduction. This applies particularly to traumatic injury hazards, ergonomic hazards and noise. Vigilance is also required to ensure exposures to coal dust and crystalline silica remain effectively controlled.     

Manufacture and use of nanomaterials: current status in the UK and global trends

This paper provides an overview of the production and use of nanomaterials (NMs), particularly in the UK. Currently, relatively few companies in the UK are identifiable as NM manufacturers, the main emphasis being the bulk markets in metals and metal oxides, and some niche markets such as carbon nanotubes and quantum dots. NM manufacturing in the UK does not reflect the global emphasis on fullerenes, nanotubes and fibres. Some assumptions have been made about the types of NM that are likely to be imported into the UK, which currently include fullerenes, modified fullerenes and other carbon-based NMs including nanotubes. Many university departments, spin-offs and private companies have developed processes for the manufacture of NMs but may only be producing small quantities for research and development (R&D) purposes. However, some have the potential to scale up to produce large quantities. The nanotechnology industry in the UK has strong R&D backup from universities and related institutions. This review has covered R&D trends at such institutions, and appropriate information has been added to a searchable database. While several companies are including NMs in their products, only a few (e.g. manufacturers of paints, coatings, cosmetics, catalysts, polymer composites) are using nanoparticles (NPs) in any significant quantities. However, this situation is likely to change rapidly. There is a need to collect more information about exposure to NPs in both manufacturing and user scenarios. As the market grows, and as manufacturers switch from the micro- to the nanoscale, the potential for exposure will increase. More research is required to quantify any risks to workers and consumers.     

深圳公立医院管理体制改革制度设计

深圳公立医院管理体制改革实行政事分开、管办分开,在理事会架构下按法定机构模式组建市医管中心,落实公立医院运营管理自主权.作者从当前公立医院管理体制的弊端入手,介绍了深圳市进行公立医院管理体制改革的基本思路及改革方案设计的主要举措,深入剖析了的改革方案的特点,并对改革效果进行了预测.     

Effects of nitrogen dioxide on red blood cells of rats: Changes in components of red cell membranes during in vivo exposure to NO2

Red cell membranes, prepared from red blood cells of rats exposed to 4, 10, or 20 ppm nitrogen dioxide (NO₂) for 1 to 10 days, were examined for evidence of changes in membrane components. Appreciable changes were not found in contents of phospholipid and cholesterol during exposure to 10 ppm NO₂. By contrast, protein content altered with the time of exposure. Moreover, changes in protein composition were observed by employing sodium dodecyl sulfate — polyacrylamide gel electrophoresis. Twenty-four-hour exposure to NO₂ at the concentration above 10 ppm resulted in a marked increase in the percentage of lysophosphatidylethanolamine (LysoPE) to the total phospholipids. The prolonged exposure to 10 ppm NO₂ gave rise to a further increase in LysoPE, whereas the percentage of phosphatidylethanolamine (PE) showed a gradual decrease. A 1-day exposure to 4.0 ppm NO₂ also caused an increase in sialic acid content and decreases in those of PE and hexose. In addition to contents of these components the percentage of LysoPE increased 5 days after exposure and the elevated values were maintained up to the end of exposure period. These results demonstrate that red blood cells in circulation exhibit different membrane properties in terms of lipid and carbohydrate composition during 10 days of exposure to 4.0 ppm NO₂.     

Investigating clusters in the workplace and beyond

Clusters of disease are common and occur in the workplace and in the general community. They often arouse considerable concern among the population. Investigations have sometimes lead to exciting new knowledge, but in general the investigation of clusters is difficult and often unrewarding, especially for community clusters. In the workplace, investigations are more likely to find associations and even new causes, but still many clusters remain enigmatic. Despite this, there are many reasons for investigating clusters, including allaying community concern and identifying uncontrolled exposures. A structure for investigating clusters in the workplace is suggested.