Medical informatics = Medecine et informatique最新文献

It is increasingly recognized that the appropriate application of information and communication technology can substantially improve communication and cooperative work processes in terms of quantity, quality and cost-effectiveness. Within large organizations, strategic decision making is one of the key cooperative processes which have to be faced. In this paper the authors discuss one example of this class of cooperative processes: research planning within the World Health Organization (WHO). The paper presents conceptual details of a process designed to assist in creating global networks of scientists, planners and field workers interested in cooperating to promote health development activities of WHO. The implementation of this process was realized in an Internet-based system to support global research planning. In particular, this application shows that the utilization of information and communication technology can not only quantitatively change existing processes, but can create new ones--and on a qualitatively improved level.

Professional mailing lists are one of the more useful and popular medical resources on the Internet. Some concern has been raised about the reliability of these uncontrolled forums. We have studied some quality aspects of a subset of Internet mailing lists on nephrology. From November 1996 to March 1997 the mailing lists NEPHROL, PDIAL-L and HYPERTEL were studied. The subscribers that posted, and a representative sample of the total number of subscribers of each list, were searched in the Medline Silver-Platter database, and their individual impact factors were obtained from the Science Citation Index. In addition, the first authors of the original articles, and short communications from the more established nephrology journals, were searched similarly, in order to compare the mailing lists with the journals. NEPHROL was the most active list (7 postings/day on average). HYPERTEL had the best average impact factor among the subscribers who posted (6.6). In general, the journals showed higher average impact factors than the mailing lists, but without statistically significant differences. HYPERTEL, PDIAL-L and NEPHROL are high quality nephrology mailing lists, and can be considered as a complement to the specialized nephrology journals.

To answer the challenges of physiologically based (PB) modelling and to enhance the research efforts in this area, a WWW site (http:/(/)www.capkr.man.ac.uk) was launched at The Centre for Applied Pharmacokinetic Research, School of Pharmacy and Pharmaceutical Sciences, University of Manchester. The site provides instant access to all the resources (data, methodology and tools), necessary to start a PB modelling study. The contents include PB modelling databases and knowledgebases, software resources, glossaries of terms, symbols and notation, and discussion groups on PB modelling and related topics. The overall aim of the WWW site is to reduce the time and the effort necessary to develop a PB model and to provide a forum for exchange of ideas between the scientists involved in the field. According to our evaluation, using the information available may reduce the duration of a typical PB modelling exercise from at least a couple of months to not more than a couple of weeks. The site's contents is targeted both to scientists with a general interest in pharmacokinetic models, and to researchers undertaking specific PB modelling projects. An additional benefit is the standardization of the procedures, rules, and data-sets, which improves the comparability of the results achieved.

The World-Wide Web is an unstructured, multimedia and multilingual information network. While most efforts have addressed the structuring issue, very few attempts have been proposed to provide support for multilingual information retrieval. Yet, medical information is now available all over the world. The MARVIN (Multi-Agent Retrieval Vagabond on Information Network) softbot and its associated medical search engine MedHunt (Medical Hunter) are a solution for helping people, who only understand a few languages, to access multilingual information.

Analysis software for medical image data tends to be expensive and usable only in a restricted environment. Therefore the aim of the current project was to implement a flexible framework for medical image processing and visualization which is portable among platforms and open to different data formats including DICOM 3.0. The software was designed as a set of tools which encapsulate specialized functionality. The tools are full stand alone applications, but they are also able to present a co-operating environment within which images and other information are communicated in real time. Currently, the emphasis is on quantitative analysis of PET data by kinetic modelling. However, general viewing capabilities are included, and the design is flexible enough that other types of processing can easily be integrated by simply plugging in Java classes. The software is successfully applied to PET data quantitation in clinical research studies and even patient studies. Portability was aimed at by encoding the programs in Java. Experience shows that the implementation of such a complex and computationally demanding Java application is feasible. Although there are major portability issues to consider, configurations can be found on which the software runs stably and at a speed comparable to C code if just-in-time compilation is available.

An analogue computer model has been constructed to simulate the dynamic behaviour of the human cardiorespiratory system for studying the effect of changes in different system-variables--as alveolar ventilation, functional residual capacity (FRC) of the human lung and the cardiac output--on the partial pressure of carbon dioxide in the arterial and mixed venous blood (pCO2a, pCO2v). The respiratory analogue computer model (RACM) simulates reliably well-known clinical physiological as well as pathological phenomena. Reducing FRC or breath rate an oscillation of pCO2a has been developed, but the mean value has not been changed. In alveolar hypoventilation the pCO2 of blood increases in good conformity with the clinical experience. Reducing cardiac output a characteristic dissociation appeared: pCO2v and pCO2a diverged from each other by increasing pCO2v and decreasing pCO2a. Since in general clinical practice of intensive care only arterial blood gas values are checked regularly, the conclusion that the patient's condition is improving by decreasing pCO2a is a serious misinterpretation in this case, because peripheral tissues are in balance with the increasing venous carbon dioxide tension, and consequently cannot get rid of this toxic agent. The computer-model-based conclusion has led to the practice of sampling both arterial and venous carbon dioxide tensions for better state assessment of seriously ill patients.

In this work the investigations of the electrical field generated by the heart, carried out using a computer simulation method are presented. Two models have been constructed approximating the chest region for the following conditions: (a) normal heart activity, and (b) open chest during the cardiac surgery. For the above models the distribution of potentials on the heart surface are determined. The source field investigated takes the following forms: dipole, multidipole, and multipole. Numerical experiments for these models show a difference between normal heart activity and of the heart in the condition when the chest is open during surgery.

In this article the problem of the construction of the geometrical-conductivity model of a human chest in a computer simulation of the cardiac electrical field, applying image diagnostic data (CT, conventional radiography and 2D projections of a torso) is presented. On the basis of these data parameters are defined which allow the determination of locations and sizes of significant chest organs. Calculations and comparison of the values of these parameters for CT and radiographic data of the example patient, using image processing methods, have been carried out. A numerical experiment has been performed to determine the epicardial maps, applying two geometrical-conductivity models of the individual patient based on CT (accurate) and radiographic (approximate) image data, respectively. The credibility of the results obtained is discussed.