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At least 199 records · Page 11Linked to original sources

PubMed1998

Conceptual integration of information databases into an Intranet.

Large information systems handle massive volume of data stored in heterogeneous sources of information. Each server has its own model of concepts representation with regard to its aims. One of the main problems encountered by end-users when accessing different servers is to match their own viewpoint on biomedical concepts with their various representations that are made in the database servers. The aim of the project ARIANE is to provide end-users with easy-to-use and natural means to access and query heterogeneous information databases. The objectives of this research work consist in building a conceptual interface by means of the Internet technology inside an enterprise Intranet, and to propose a method to realize it. Moreover, this method provides designers of web sites with a powerful tool to manage them on the basis of an ontology of the biomedical domain. This method is based on the knowledge sources provided by the Unified Medical Language System project of the U.S. National Library of Medicine and exploits intensively the conceptual graphs theory.

Computer Communication Networks↗

PubMed2003

Married women's satisfaction with their choice of contraception.

Fertility reduction has been promoted in Taiwan for almost 40 years. However, little research has been done into women's satisfaction with the methods of contraception they use. The purpose of this study is to explore their level of satisfaction, along with the related factors of demographic data, giving birth and types of contraceptives used. Employing a cross-sectional design, self-administered questionnaires were distributed to women in the northern area of Taiwan. Purposive sampling was used to collect data from 97 women. The results reveal a mean age of 37.21 years. The mean length of marriage was 13.53 years. The majority (43.29 %) of the subjects were graduates of high school or vocational school. Of the subjects, 92.78 % had given birth, while 35.05 % had experienced abortion. IUDs (Intrauterine Devices) were the most commonly used form of contraceptive, while 63.92 % used other types. Satisfaction was divided into four categories: satisfaction with contraceptive services, satisfaction with contraceptive knowledge source, satisfaction with contraceptive experience and satisfaction with spousal support. Overall, subjects were happy with the contraceptive methods they used. There was no statistical difference in satisfaction between demographic variances, fertility or contraceptive methods applied. Though subjects showed satisfaction with contraception, we feel women's subjective experiences should be investigated in order to promote even better satisfaction. Possible future studies could include random sampling and an examination of the related factors of contraceptive satisfaction.

Adult↗

PubMed2002

[Why controlled studies may lead to misleading and unconfirmed therapeutic concepts--a critical view of evidence-based medicine].

The concept of evidence-based medicine has gathered widespread support during recent years. While this concept has clear merits in compiling and qualifying up-to-date information for clinical decisions, it should be viewed with caution as the sole valid knowledge source for clinical decision-making. The limitations of such an approach are particularly striking when reviewing two key developments in modern cardiology, fibrinolysis and acute percutaneous intervention in acute myocardial infarction. In both cases, early studies and meta-analyses showed no benefit for these therapeutic interventions over earlier treatment. Only after further refinement (mainly in dosage, time window, concomitant heparin therapy for fibrinolysis, and the introduction of stents and IIb/IIIa inhibitors for acute intervention) did these therapies become universally acknowledged. It is therefore crucial to understand that especially for physicians actively participating in the development of a clinical field clinical decisions cannot be exclusively based on published evidence. Another important problem to consider is the time gap between the emergence of new therapies and the publication and reception by the medical audience, in particular in rapidly evolving fields as cardiology. While it is clear that clinical decision-making must be backed by solid knowledge of the published evidence, in particular the specialist involved in-depth in the field may use not yet proven therapeutic concepts and measures to the patient's advantage.

Angioplasty, Balloon, Coronary↗

PubMed2006

Particulate matter over a seven year period in urban and rural areas within, proximal and far from mining and power station operations in Greece.

Lignite mining operations and lignite-fired power stations result in major particulate pollution (fly ash and fugitive dust) problems in the areas surrounding these activities. The problem is more complicated, especially, for urban areas located not far from these activities, due to additional contribution from the urban pollution sources. Knowledge of the distribution of airborne particulate matter into size fraction has become an increasing area of focus when examining the effects of particulate pollution. On the other hand, airborne particle concentration measurements are useful in order to assess the air pollution levels based on national and international air quality standards. These measurements are also necessary for developing air pollutants control strategies or for evaluating the effectiveness of these strategies, especially, for long periods. In this study an attempt is made in order to investigate the particle size distribution of fly ash and fugitive dust in a heavy industrialized (mining and power stations operations) area with complex terrain in the northwestern part of Greece. Parallel total suspended particulates (TSP) and particulate matter with an aerodynamic diameter less than 10 microm (PM10) concentrations are analyzed. These measurements gathered from thirteen monitoring stations located in the greater area of interest. Spatial, temporal variation and trend are analyzed over the last seven years. Furthermore, the geographical variation of PM10 - TSP correlation and PM10/TSP ratio are investigated and compared to those in the literature. The analysis has indicated that a complex system of sources and meteorological conditions modulate the particulate pollution of the examined area.

Air Pollutants↗

PubMed1999

Attitudes to water fluoridation in South Africa 1998. Part I. Analysis by age, sex, population and province.

The successful implementation of water fluoridation (WF) depends upon support from the public. A survey was conducted in 1998 by the Human Sciences Research Council to assess attitudes of the South African population towards WF. A representative sample of 2,220 persons over the age of 18 years was interviewed. Questions relating to current knowledge, sources of information, the purpose of water fluoridation and its desirability as a public health measure were put to respondents. Only 25% of the population had heard or read of WF. The major sources of information were the electronic and printed media (40% and 27% respectively), while 2.5% heard about it from dentists. Just over a third of the sample (35.5%) identified the purpose of WF as protecting teeth from decay; 28% said it was to purify water and 28.5% were uncertain of, or did not know its purpose. Nearly two-thirds (61.9%) indicated that fluoride should be added to drinking water if it can reduce tooth decay, while 9% were not in favour and 29% were uncertain. The results suggest that most people do not know what WF is or does, though most were in agreement that it should be implemented to reduce tooth decay.

Adolescent↗

PubMed2002

When is schematic knowledge used in source monitoring?

Source monitoring involves judgments regarding the origin of information (M. K. Johnson, S. Hashtroudi, & D. S. Lindsay, 1993). When participants cannot remember the source in a source-monitoring task, they may guess according to their prior schematic knowledge (U. J. Bayen, G. V. Nakamura, S. E. Dupuis, & C.-L. Yang, 2000). The present study aimed at specifying conditions under which schematic knowledge is used in source monitoring. The authors examined the time course of schema-based guesses with a response-signal technique (A. V. Reed, 1973), and multinomial models that separate memory and guessing bias. Use of schematic knowledge was observed only when asymptotic old-new recognition was low. The time course of schematic-knowledge retrieval followed an exponential growth function. Implications for theories of source monitoring are discussed.

Adolescent↗

PubMed2004

Web-accessible proteome databases for microbial research.

The analysis of proteomes of biological organisms represents a major challenge of the post-genome era. Classical proteomics combines two-dimensional electrophoresis (2-DE) and mass spectrometry (MS) for the identification of proteins. Novel technologies such as isotope coded affinity tag (ICAT)-liquid chromatography/mass spectrometry (LC/MS) open new insights into protein alterations. The vast amount and diverse types of proteomic data require adequate web-accessible computational and database technologies for storage, integration, dissemination, analysis and visualization. A proteome database system (http://www.mpiib-berlin.mpg.de/2D-PAGE) for microbial research has been constructed which integrates 2-DE/MS, ICAT-LC/MS and functional classification data of proteins with genomic, metabolic and other biological knowledge sources. The two-dimensional polyacrylamide gel electrophoresis database delivers experimental data on microbial proteins including mass spectra for the validation of protein identification. The ICAT-LC/MS database comprises experimental data for protein alterations of mycobacterial strains BCG vs. H37Rv. By formulating complex queries within a functional protein classification database "FUNC_CLASS" for Mycobacterium tuberculosis and Helicobacter pylori the researcher can gather precise information on genes, proteins, protein classes and metabolic pathways. The use of the R language in the database architecture allows high-level data analysis and visualization to be performed "on-the-fly". The database system is centrally administrated, and investigators without specific bioinformatic competence in database construction can submit their data. The database system also serves as a template for a prototype of a European Proteome Database of Pathogenic Bacteria. Currently, the database system includes proteome information for six strains of microorganisms.

Bacterial Proteins↗

PubMed1994

Knowledge-based cephalometric analysis: a comparison with clinicians using interactive computer methods.

In modern orthodontic practice great reliance is placed on systematic and objective methods of characterizing craniofacial forms, using measurements based on both hard and soft tissue landmarks. Lateral skull X-ray images are routinely used in cephalometric analysis to provide quantitative measurements useful to clinical orthodontists. It is argued that a model- and knowledge-based methodology provides the best approach in successfully interpreting digitized lateral skull radiographs. A rule-based segmentation system, making use of an image appearance model, is used to extract image features from gray-level images. Complex image features and cephalometric landmarks are constructed from these segmented component features. A predictive model, defining picture structure, allows location hypotheses to be made for image features. The underlaying structure of the location model provides the basis for a geometric constraint model of use in discriminating between image feature candidates. A blackboard system is used to organize these tasks hierarchically, with individual knowledge sources grouped according to function and the individual stages of the adopted image interpretation cycle. Quantitative results demonstrate the superiority of this complex system over its component segmentation system run on its own. Comparisons with clinicians demonstrate both the strengths and the weaknesses of the present system. Comparisons with previous systems are favorable.

Cephalometry↗

PubMed2001

[Physicians, internet and new knowledge. Utilization and efficiency of new continuing education media in the hospital].

BACKGROUND AND OBJECTIVES: The application of new information technologies will have a lasting impact on the physicians' working environment. Not only will classic learning methods change, but also ways of communication and strategies to find relevant information. This survey is designed to demonstrate current methods of and demand for continuing medical education and communication. METHODS: 110 participating physicians (26% female, 74% male) in nine different regional hospitals were asked regarding "continuing medical education", "communication" and "use of computerized technology". RESULTS: Most physicians regard their colleagues, scientific journals, textbooks and scientific meetings as most useful. The internet, scientific staff at research institutions and pharmaceutical representatives were valued as less useful. Physicians regarded scientific basis, speed and user-friendliness as the most important features of potential data and knowledge sources. Case specificity, German language and interactivity were viewed as less important. Most physicians expressed a growing need for education regarding use of e-mail as a communication tool and internet research techniques. CONCLUSION: Continuing medical education is in strong demand. The successful introduction of modern information technologies into physicians' daily work may and should be enhanced by specifically tailored training courses.

Adult↗

PubMed2002

The completeness of existing lexicons for representing radiology report information.

Although most medical lexicons contain up to 80% of clinical terms used in an ambulatory patient medical records archive, preliminary research suggests that they may be far less complete for radiology terms. We therefore compared the likelihood that several existing medical lexicons would contain terms found in a radiology report to the likelihood they would contain terms found in an ambulatory care medical record. We used three samples of imaging terms to assess the completeness of existing lexicons for medical imaging: (1) a random sample of imaging terms from the Unified Medical Language System Large Scale Vocabulary Test (UMLS-LSVT; n = 218), (2) terms actually used in the first 80 clinical knee magnetic resonance imaging reports generated by the routine clinical use of a structured reporting system (eDictation, Marlton, NJ; n = 76), and (3) terms listed in a glossary of thoracic imaging prepared by the Fleischner Society (n = 173). Using the UMLS Web-based Knowledge Source Server (http://umlsks.nlm.nih. gov/), we measured the rate at which terms in each of the above three sources were found in the UMLS and two of its major constituent terminologies: ICD-9-CM and SNOMED International. ICD-9-CM contained matches for 3%, 8%, and 11% of terms from the Fleischner Society Glossary, eDictation, and NLM-LSVT, respectively. SNOMED International contained matches for 32%, 46%, and 36% of terms from the Fleischner Society Glossary, eDictation, and NLM-LSVT, respectively. The UMLS contained matches for 36%, 50%, and 45% of terms from the Fleischner Society Glossary, eDictation, and NLM-LSVT, respectively. The assessed vocabularies were least likely to contain a term from the Fleischner Society Glossary and most likely to contain a term from the eDictation lexicon. The UMLS was the most complete, and ICD-9 was the least complete of the three systems evaluated. No lexicon achieved greater than 50% completeness for any test set of imaging terms. Our results show that no single lexicon is sufficiently complete to allow comprehensive indexing, search, and retrieval of radiology report information. These results confirm the few results available from the medical literature indicating that existing controlled vocabularies are insufficiently complete to represent the contents of radiology reports. A subjective analysis of these results may identify particular imaging sub-areas for which new terms should be developed.

Humans↗

PubMed1990

Use of condoms as contraceptive and disease preventive measures among residents of Jos, northern Nigeria.

The effectiveness, acceptability and protective aspects of condoms as both contraceptive and disease control measures was evaluated in 168 male residents of Jos in Nigeria. They were aged between 15 and 40 years and were attending the Family Planning Clinic of the Jos University Teaching Hospital. The results showed that the majority (87.5%) of our patients were in the 21 to 30 years age group and most of the clients had used condoms for between 1 to 5 years. A good number of our clients (40.5%) used condom because it protects them against venereal disease while others felt it was safe and effective. The Family Planning Clinic was the main source of knowledge of the condom among our clients (42.9%), and the condom was rated as good or excellent by 137 (81.5%) clients. The only side effect of condom usage which featured prominently among our clients was reduced sexual excitement. The results were compared with studies carried out elsewhere. It was concluded that the condom could be an acceptable and effective form of contraception in this population. The users must, however, be highly motivated so as to use it during every act of coitus for optimal efficacy.

Adolescent↗

PubMed1995

Free text analysis.

In the context of hospital information systems (HIS) medical free text analysis is reviewed with respect to current automated approaches to literature retrieval, case retrieval and fact retrieval from textual data in the patient record. The Unified Medical Language System (UMLS) project has enormously stimulated current research. It is expected that UMLS knowledge sources and SNOMED III (which need a translation into other languages as soon as possible) as well as the conceptual graphs formalism, could become standards to utilize free text information contained in HIS databases.

Abstracting and Indexing↗

PubMed1994

The role of the UMLS in 'storing' and 'sharing' across systems.

We will argue that 'sharing', 're-use', 're-purposing', and 'addition' of health care information is difficult, intrinsically; that the best way to overcome the difficulty is to start doing it, as soon as possible, and that the UMLS Knowledge Sources provide the best place to start. We recommend that the UMLS be used as a default source of biomedical concept names and relationships, as a comprehensive, data-based, 'reference model', and as an example of a large, ecumenical, evolving, continuously updated source of re-usable health care information.

Computer User Training↗

PubMed1976

The cross-reactivity of IgE antibodies with pollen allergens. II. Analyses of various species of ragweed and other fall weed pollens.

Although the antigenic composition of short ragweed pollen has been extensively investigated, very few studies have analyzed the allergenic cross-reactivity among various types of ragweed pollens. Using a serum pool from patients sensitive to short ragweed, we studied the cross-reactivity of IgE antibodies to six ragweeds by the radioallergosorbent test. Extracts were analyzed for their inhibitory activities with solid-phase allergens prepared from all of the ragweed pollens. Also, samples of serum were absorbed with the various solid-phase allergens and the reactivity of the remaining IgE antibodies was determined. Two patterns of reactivity were observed. Short, giant, western, and false ragweeds displayed comparable reactivity in both inhibition and absorption experiments. Slender and southern ragweed were considerably less active, indicating that they lacked allergenic groupings possessed by the other species. These same patterns of cross-reactivity were found using ragweed pollens from four commercial sources. Knowledge of these patterns of cross-allergenicity is of importance for diagnosis and treatment of sensitive patients as well as for in vitro standardization of extracts.

Absorption↗

PubMed1990

Overcoming deficiencies of the rule-based medical expert system.

One of the current deficiencies of the rule-based expert system is its static nature. As these systems are applied to medicine, this shortcoming becomes accentuated by: the rapid speed at which new knowledge is generated, the regional differences associated with the expression of many diseases, and the rate at which patient demographics and disease incidence change over time. This research presents a solution to the static nature of the rule-based expert system by proposing a hybrid system. This system consists of an expert system and a statistical analysis system linked to a patient database. The additional feature of a rule base manager which initiates automatic database analysis to refresh the statistical correlation of each rule ensures a dynamic, current, statistically accurate rule base. The philosophical differences between data and knowledge are also addressed as they apply to this type of hybrid system. The system is then used to generate four rule bases from different knowledge sources. These rule bases are then compared.

Artificial Intelligence↗

PubMed1993

Facial cutaneous reconstructive surgery: facial flaps.

Basic principles of aesthetics and function important for successful facial cutaneous reconstructive surgery with local flaps include the use of appropriate tissue donor sources, knowledge of the mechanisms, dynamics, and effects of tissue movement, and techniques for scar camouflage. Useful flaps for defects in each of the facial cosmetic units are reviewed with these principles used as guidelines.

Cheek↗

PubMed2006

Mémoire: A framework for semantic interoperability of case-based reasoning systems in biology and medicine.

OBJECTIVE: Mémoire is a framework for sharing and distributing case bases and case-based reasoning (CBR) systems in biology and medicine. METHODS AND MATERIAL: This paper first introduces the semantic Web approach to build a better Web where search engines, knowledge sources and servers, applications and services can live, work, and learn in cooperation. This semantic approach is particularly well suited for biomedical domains because significant ontologies have been developed there and constitute a sound basis for the standardization effort required for the semantic Web. Case-based reasoning systems in biomedicine have also benefited from these biomedical ontologies and models. RESULTS: This article demonstrates for three such systems how a semantics infused approach in CBR gives better, more accurate results in CBR. From this previous work on a semantic approach in CBR in biomedicine, the Mémoire framework has evolved. CONCLUSION: Mémoire proposes a unified OWL-based representation language for cases and case-based ontologies in biomedicine, where a Web Ontology Language (OWL) is a language to represent ontologies on the Web. Mémoire provides a set of tools for building case-based reasoning systems compliant with its language. Mémoire is extensible and can be adapted to different types of biomedical application domains, tasks, and environments. Mémoire will permit bridging the gap within the multiple case-based reasoning systems dedicated to a single domain, and make available to agents and Web services the case-based competency of the CBR systems adopting its interchange language. The approach could be extended to other application domains of CBR.

Artificial Intelligence↗

PubMed2006

Using ontologies linked with geometric models to reason about penetrating injuries.

OBJECTIVE: Medical assessment of penetrating injuries is a difficult and knowledge-intensive task, and rapid determination of the extent of internal injuries is vital for triage and for determining the appropriate treatment. Physical examination and computed tomographic (CT) imaging data must be combined with detailed anatomic, physiologic, and biomechanical knowledge to assess the injured subject. We are developing a methodology to automate reasoning about penetrating injuries using canonical knowledge combined with specific subject image data. METHODS AND MATERIAL: In our approach, we build a three-dimensional geometric model of a subject from segmented images. We link regions in this model to entities in two knowledge sources: (1) a comprehensive ontology of anatomy containing organ identities, adjacencies, and other information useful for anatomic reasoning and (2) an ontology of regional perfusion containing formal definitions of arterial anatomy and corresponding regions of perfusion. We created computer reasoning services ("problem solvers") that use the ontologies to evaluate the geometric model of the subject and deduce the consequences of penetrating injuries. RESULTS: We developed and tested our methods using data from the Visible Human. Our problem solvers can determine the organs that are injured given particular trajectories of projectiles, whether vital structures--such as a coronary artery--are injured, and they can predict the propagation of injury ensuing after vital structures are injured. CONCLUSION: We have demonstrated the capability of using ontologies with medical images to support computer reasoning about injury based on those images. Our methodology demonstrates an approach to creating intelligent computer applications that reason with image data, and it may have value in helping practitioners in the assessment of penetrating injury.

Diagnosis, Computer-Assisted↗