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2.
Arne Skretting Elin Strandmyr Mette W. Lindegaard 《European journal of nuclear medicine and molecular imaging》1990,17(1-2):10-14
A prototype version of a recently developed transmission phantom for simulation of radionuclide bone studies was used in a Norwegian nationwide quality assurance project. The design of the phantom made it possible to perform a receiver operation characteristic (ROC) examination with respect to the detection of radionuclide accumulation in the ribs. The participants were also asked to report accumulation in the spinal column. Images obtained by means of a uniform source and a four-quadrant bar pattern were used to judge resolution and homogeneity with the collimator used in the bone studies. The overall performance of the laboratories was satisfactory, but considerable variations were found. There was a marked correlation between the physician's performance and the resolution and homogeneity of the camera. Reports from stationary imaging were generally better than those that were based on whole-body scans. 相似文献
3.
Physical and biological properties of U.S. standard endotoxin EC after exposure to ionizing radiation.
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Techniques that reduce the toxicity of bacterial endotoxins are useful for studying the relationship between structure and biological activity. We used ionizing radiation to detoxify a highly refined endotoxin preparation. U.S. standard endotoxin EC. Dose-dependent changes occurred by exposure to 60Co-radiation in the physical properties and biological activities of the endotoxin. Sodium dodecyl sulfate-polyacrylamide slab gel electrophoresis showed gradual loss of the polysaccharide components (O-side chain and R-core) from the endotoxin molecules. In contrast, although endotoxin revealed a complex absorption pattern in the UV range, radiation treatment failed to modify that pattern. Dose-related destruction of the primary toxic component, lipid A, was suggested by the results of activity tests: both the pyrogenicity and limulus reactivity of the endotoxin were destroyed by increasing doses of radiation. The results indicate that the detoxification is probably due to multiple effects of the ionizing radiation on bacterial lipopolysaccharides, and the action involves (i) the destruction of polysaccharide moieties and possibly (ii) the alteration of lipid A component of the endotoxin molecule. 相似文献
4.
Role of endotoxemia in cardiovascular dysfunction and lethality: virulent and nonvirulent Escherichia coli challenges in a canine model of septic shock.
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W D Hoffman R L Danner Z M Quezado S M Banks R J Elin J M Hosseini C Natanson 《Infection and immunity》1996,64(2):406-412
We investigated whether the severity of septic shock is determined by virulence factors associated with or the levels of endotoxemia produced by two Escherichia coli strains. Canines were challenged intraperitoneally with an E. coli strain (O6:H1:K2) that has virulence factors associated with human disease or with an equal dose of a nonvirulent strain (O86:H8) that lacks these factors. Both strains were administered in viable, heat-killed, and purified endotoxin forms. Median survival times with the virulent strain compared with the nonvirulent strain were shorter with viable bacteria (5 x 10(10) CFU/kg) (144 h versus > 672 h; Wilcoxon, P = 0.03), longer with heat-killed bacteria (5 x 10(9) CFU/kg) ( > 676 h versus 26 h; P = 0.03), and similar with purified endotoxin (15 mg/kg) (28 h versus 48 h; P = 0.71). However, whether the challenge contained viable bacteria, heat-killed bacteria, or purified endotoxin, the virulent strain produced less endotoxemia (P = 0.001). Hence, the changing outcomes with differing forms of the two strains cannot be attributed solely to endotoxin levels. The viable virulent strain caused less endotoxemia but more harm, and this does not appear to be explained by a more potent endotoxin or other heat-stable component. This study suggests that circulating endotoxin levels per se are less important in the outcome of septic shock than virulence factors associated with E. coli strains. Furthermore, the data call into question the significance of the endotoxin concentration in the blood in predicting the severity of shock and the lethality of gram-negative infections. 相似文献
5.
D J Lawrie R J Elin V J Gill T L Lewis J D MacLowry F G Witebsky 《Journal of clinical microbiology》1979,10(6):861-875
The computer system used by the Microbiology Service of the Clinical Pathology Department, Clinical Center, National Institutes of Health is discussed. This microbiology subsystem is a part of a dedicated on-line laboratory computer system used by the entire department. The laboratory computer is connected on-line to a hospital computer which provides patient admission, transfer, and discharge data. Mark sense worksheets and cathode ray tube terminals are used for result entry and correction. Cumulative patient reports are printed. Results for both active and completed accessions can be easily retrieved on cathode ray terminals in the laboratory. All laboratory data are archived on magnetic tape from which a research data base and microfiched laboratory records are generated. The manner in which the system is integrated in the routine operation of the microbiology laboratory is emphasized. In addition, some of the costs, benefits, liabilities, and pitfalls associated with the introduction of the computer in the laboratory are reviewed. Finally, we have presented our concept of some of the future enhancements to our present system and some of the directions in which any future microbiology system might develop. 相似文献
6.
Knut Hagen Lars J Stovner Frank Skorpen Elin Pettersen John-Anker Zwart 《BMC medical genetics》2007,8(1):34
Background
The catechol-O-methyltransferase (COMT) gene contains a functional polymorphism, Val158Met which has been related to common diseases like cancer, psychiatric illness and myocardial infarction. Whether the Val158Met polymorphism is associated with survival has not been evaluated in the general population. The aim of this prospective study was to evaluate the impact of codon 158 COMT gene polymorphism on survival in a population-based cohort. 相似文献7.
8.
Persistent organochlorines, sedentary occupation, obesity and human male subfertility 总被引:4,自引:0,他引:4
Magnusdottir EV Thorsteinsson T Thorsteinsdottir S Heimisdottir M Olafsdottir K 《Human reproduction (Oxford, England)》2005,20(1):208-215
BACKGROUND: Studies have suggested that the quality of human semen has been declining over recent decades, presumably because of lifestyle or environmental factors. METHODS: Polychlorinated biphenyls and organochlorine pesticides were analysed in the plasma of 25 men with poor semen quality, 20 men with normal semen quality and idiopathic subfertility and 27 men with normal semen quality and female factor subfertility. Samples of seminal fluid were also analysed to assess the relationship between the levels in blood and semen. RESULTS: The results indicate no difference in the levels of organochlorines between the groups. The levels of organochlorines in seminal fluid were proportional to the levels in plasma, but approximately 40 times lower. Men with poor semen quality were three times more likely to be obese than men with normal semen quality. There was also a significant negative correlation between semen quality parameters and body mass index among men with normal semen quality. The prevalence of sedentary work was lowest among men with the best semen quality. CONCLUSIONS: Poor semen quality was found to be associated with sedentary work and obesity but not with plasma levels of persistent organochlorines. More research is needed to assess whether sedentary lifestyle and obesity are causal factors in the decline of semen quality. 相似文献
9.
Comparison of automated and manual methods for urinalysis 总被引:1,自引:0,他引:1
R J Elin J M Hosseini J Kestner M Rawe M Ruddel H H Nishi 《American journal of clinical pathology》1986,86(6):731-737
The authors compared results for accuracy and precision obtained by a semiautomated prototype International Remote Imaging Systems, Inc. (IRIS) urinalysis workstation (IUW) with those from quantitative manual urinalysis (QMU). Three technologists skilled in urinalysis each performed 172 urinalyses with both the IUW and QMU methods. The results show that the IUW method is likely to yield comparable counts for particulate analytes compared with the QMU, except for casts. The QMU reported significantly (P less than 0.001) more casts than the IUW method. This difference is related to at least a ninefold greater volume of untreated urine examined by the QMU method than the IUW method. The IUW method may provide a more accurate result than the QMU method at very low and high concentrations of particulate analytes. The result from 24 blind duplicate urines also analyzed by each of the three technologists with both methods showed comparable precision for particulate analytes between the two methods except for red blood cells; the QMU method had significantly (P less than 0.001) better precision for this analyte. 相似文献
10.
Aanesen Fiona Øiestad Britt Elin Grotle Margreth Løchting Ida Solli Rune Sowden Gail Wynne-Jones Gwenllian Storheim Kjersti Eik Hedda 《Journal of occupational rehabilitation》2022,32(2):306-318
Journal of Occupational Rehabilitation - Purpose To perform a process evaluation of a stratified vocational advice intervention (SVAI), delivered by physiotherapists in primary care, for people on... 相似文献