基层医院CR、DR摄影中一些问题的探讨

X线数字化摄影开拓了X线影像技术的新领域,随着CR、DR的诞生与发展,医院数字X线摄影设备的发展问题摆在我们的面前。电子信息、数字化已经给我们的工作带来的巨大变化。医学影像设备和计算机的发展,常规X线摄影实现了数字存储和传输,由计算机X线摄影(CR)到直接数字X线摄影(DR),彻底改变了放射科传统的摄影模式,实现了普通X线摄影的数字化革命。适合我国国情的X线投照标准、放射工作人员以及公众的年辐射剂量当量也已日趋完善并统一。     

计算机X线摄影与传统X线摄影的对比

随着医学影像高、精、尖技术的迅猛发展,传统X线摄影已逐步显示其弊端。校医院也面临着机遇与发展两大主题,放射科的发展起着关键的作用。我们结合清华大学医院放射科一年发展的现状,分析20例胸部传统X线摄影与计算机X线摄影对比的情况,希望能提供参考意见。     

计算机X线摄影与传统X线摄影的对比

随着医学影像高、精、尖技术的迅猛发展,传统X线摄影已逐步显示其弊端[1]。校医院也面临着机遇与发展两大主题,放射科的发展起着关键的作用。我们结合清华大学医院放射科一年发展的现状,分析20例胸部传统X线摄影与计算机X线摄影对比的情况,希望能提供参考意见。传统的X线成像是经X线摄照,将影像信息记录在胶片上,在显定影处理后,影像才能于照片上显示。计算机X线成像(computedradio graphy,CR)则是将X线摄照的影像信息记录在影像板(imageplate,IP)上,经读取装置读取,由计算机计算出一个数字化图像,经数字/模拟转换器转换,于荧屏上显示…     

直接数字化影像（DR）技术特点及临床应用

随着医学影像设备和计算机的发展，常规X线摄影也实现了数字存储和传输，由计算机X线摄影（CR）到直接数字X线摄影（DR），彻底改变了放射科传统的摄影模式，实现了普通X线摄影的数字化革命。数字X线设备，极大地提高了影像的对比度和分辨率，强大的图像后处理（图像的放大、反转、滤波、降噪、灰阶变换、不同窗宽、窗位的调整等技术）很大程度上扩展了影像的动态观察范围，DR系统对X线敏感性高，直接转换技术使X线的吸收率高于间接转换的3～4倍，图像灰度精度更高，层次丰富。能极大地提高医院的诊断水平和工作效率，直接数字X线摄影各大医院相继推广应用。     

成像板对计算机X线图像质量的影响

在医学影像领域内计算机X线摄影正在取代普通X线摄影,新设备的引进使医学影像发生了质的变化,解决了图像的存储、传送和管理,CR(计算机X线摄影术)系统的关键在于使用了可接受模拟信息又可实现模拟信息数字化的成像板(简称IP板)代替了普通摄影中的屏/胶组合,从而实现了数字化影像的重建和显示以及网络传输和管理.IP板的正确使用对图像质量有着重要的影响.     

激光照相机的结构、原理和特点

医用激光照相机是现代医学成像系统中最先进的硬拷贝技术。目前广泛地应用于CR、CT、MRI、DSA等数字化医学影像检查设备。由于计算机X线摄影(computed radioyraphy,CR)系统使用的是数字化成像技术,可以将所得的信息按诊断的要求进行图像处理,为X线影像的长期保存和高效率的检索提供了可能性。     

数字化X线摄影的进展与实施

医学影像数字化主要是指影像以数字方式输出,影像数据利用计算机强大的高速运算处理能力方便快速地进行存储、处理、传输和显示。随着计算机和电子技术的飞速发展,CT、MRI、DSA、US、ECT等全新的成像技术进入医学领域,不仅提高了影像诊断的水平,同时实现了诊断信息的数字化,为逐步建立的医学影像图像存档传输系统PACS和远程医疗奠定了基础[1]。 传统X线摄影是医学影像领域中应用最早、迄今仍最广泛的检查方法,但也是医学影像学中最晚实现数字化的成像技术。21世纪将是数字化、网络化的时代,传统X线摄影数字化是医学影像…     

X射线摄影技术数字化研究进展

明确了X射线摄影的概念和重要性,概述了胶片X射线摄影技术、计算机X射线摄影技术、数字化X射线摄影技术以及X射线摄影数字化的研究进展,重点介绍了数字化X射线摄影技术中的非直接数字化X射线摄影技术和直接数字化X射线摄影技术,分析了各种X射线摄影技术之间的差别与优势,指出数字化X射线摄影技术及系统是当今国内医疗仪器行业重要研究课题之一,是医学影像数字化发展的必然趋势。     

浅谈对数字X线机摄影过程的优化

本文通过对传统屏片系统与数字X线摄影进行比较,阐明数字X线摄影使摄影工作流程简化,并从RIS-PACS系统的集成和摄影技术参数的调整来阐述数字X线摄影过程的优化,提高了医学影像质量。     

数字化X线摄影成像及评价

数字化影像技术在近20 a得到迅速的发展,因此被评价为20世纪医学发展的重要成就之一.电子计算,信息技术的飞速发展,为医学影像技术的发展提供了充足的动力,数字化已成为医学影像技术发展的必然方向,计算机X线摄影(CR)等数字化影像系统及应用已成为国内医学界的关注[1].全新的数字化影像技术应用于临床,丰富了形态医学诊断的信息、层次,逐步改变了传统放射技术并与快速发展的计算机,网络技术融合,大大提高了医学影像的质量.     

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.     

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.     

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.     

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.