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Biomedical subjects

F Norman

Publications and source records attributed to F Norman.

10 recordsLinked to original sources
PubMed2006

Auto-ignition and upper explosion limit of rich propane-air mixtures at elevated pressures.

The auto-ignition limits of propane-air mixtures at elevated pressures up to 15 bar and for concentrations from 10 mol% up to 70 mol% are investigated. The experiments are performed in a closed spherical vessel with a volume of 8 dm3. The auto-ignition temperatures decrease from 300 degrees C to 250 degrees C when increasing the pressure from 1 bar to 14.5 bar. It is shown that the fuel concentration most sensitive to auto-ignition depends on initial pressure. A second series of experiments investigates the upper flammability limit of propane-air mixtures at initial temperatures up to 250 degrees C and pressures up to 30 bar near the auto-ignition area. Finally the propane auto-oxidation is modelled using several detailed kinetic reaction mechanisms and these numerical calculations are compared with the experimental results.

Air↗
PubMed2005

Long-term persistence of molecular disease after histological remission in low-grade gastric MALT lymphoma treated with H. pylori eradication. Lack of association with translocation t(11;18): a 10-year updated follow-up of a prospective study.

BACKGROUND: Localized low-grade gastric mucosa-associated lymphoid tissue (MALT) lymphoma can regress after Helicobacter pylori eradication, but IgV(H) gene monoclonality may persist. We studied the long-term histological and molecular follow-up of 24 patients and the possible association of t(11;18) with the persistent monoclonality. PATIENTS AND METHODS: From January 1994, 24 untreated patients with stage I low-grade gastric MALT lymphoma associated with H. pylori were prospectively studied. They all received eradication treatment and were sequentially followed-up with endoscopies for histological and molecular studies. Rearrangement of the IgV(H) gene was studied by PCR analysis. MALT1 locus alterations were studied by FISH. RESULTS: Twenty-two of the 24 patients (91%) achieved disappearance of the lymphoma. Eighteen (82%) of the 22 histologically cured patients and 16 of the 19 (84%) with long follow-up had monoclonality. Three patterns of development of IgV(H) gene rearrangements were observed: four patients (21%) had polyclonal rearrangements; eight (58%) had maintained/intermittent monoclonality and four (21%) had occasional monoclonality, mostly after H. pylori reinfection. Only one patient (6%) with persistent monoclonality relapsed. The remaining 18 patients maintained the remission, despite the persistent monoclonality in 15, for a median of 66 months (range 20-113). t(11;18) was not found in any of the patients with persistent monoclonality. Time and the number of endoscopies performed were not related with the occurrence of monoclonality. CONCLUSIONS: In stage I low-grade gastric MALT lymphoma eradication of H. pylori achieves prolonged histological remission in 90% of patients, but molecular remission is not accomplished in most cases. Molecular disease persists for years, but is not associated with t(11;18).

Anti-Bacterial Agents↗
PubMed1999

Genetic information resources: a new field for medical librarians.

The Human Genome Project is generating unprecedented quantities of new genetic information. The new discipline of bioinformatics has created many new molecular biology databanks to store the results of the Human Genome Project. This data is expected to be the information source for biomedical science in the 21st century. As molecular biology research moves out of the laboratory and becomes molecular medicine, a growing number of people need access to genetic information. Medical students, healthcare practitioners and patients need help in finding appropriate information. Medical librarians should know how to search key genetic information resources and should have a basic understanding of the type of information contained in each.

Databases, Bibliographic↗
PubMed1997

Digital libraries--a quality concept.

The idea of digital libraries is not new, but recent developments have made the realisation of this idea more of a practical possibility than ever before. In particular, the availability of tools for easy access to information and for easy production of new information has encouraged traditional publishers to make their information available in digital networked form. but also made it possible for many individual authors to directly publish their own information on the Internet, bypassing traditional publishers and established bibliographic systems. Managing these new information resources is the task of Internet digital libraries such as OMNI. A key issue is the need to signpost the quality of information sources. A variety of ways of doing this are possible.

Computer Communication Networks↗
PubMedDate not supplied

Organizing medical networked information (OMNI).

The Internet has become a major source of biomedical information over the last 5 years. Several projects have recently been established to help users find respectable information sources quickly. OMNI (Organizing Medical Networked Information) is one such filtering and indexing project. OMNI has focused on the quality of information and the application to Internet resources of standard tools for organizing information such as the National Library of Medicine's Medical Subject Headings and the Dublin Core metadata format. Now two years old, the OMNI project fulfils a valuable role for the UK biomedical community, through its gateway service (http:@omni.ac.uk), its printed resource guides and its training workshop programme. OMNI is also a focus for biomedical metadata activities in the UK. The gateway continues to grow in size and further work on information quality issues and integration is planned.

Abstracting and Indexing↗
PubMedDate not supplied

Shear thickening of DNA in SDS lysates.

Cells of Escherichia coli were subjected to lysis by an alkali detergent treatment (sodium dodecyl sulphate). The rate of detergent lysis was not first order. The rheological properties of the lysate were measured using a controlled stress rheometer. Detergent-lysed cells produced a lysate which showed marked non-Newtonian properties. The material showed a shear thickening at specific low shear stress conditions. The acceleration of the cone during the ascent stage of a flow curve, influenced the shape of the flow curves. These findings are discussed in relation to the form of bacterial DNA in solution.

DNA, Bacterial↗