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991.
992.
D Lieberman P Shvartzman D Lieberman M Ben-Yaakov Z Lazarovich S Hoffman R Mosckovitz B Ohana M Leinonen D Luffy I Boldur 《Canadian Metallurgical Quarterly》1998,17(10):685-689
A prospective study was conducted over a 3-month winter period in three general practice clinics in an urban population in southern Israel to identify the etiological agents of respiratory tract infections (RTI) in adults. RTI was defined as an acute febrile illness with cough, coryza, sore throat or hoarseness. Serum samples were taken from all patients in both the acute and convalescent phases of their illness. Tests were conducted for detection of 17 microorganisms known to cause RTI, including serological tests for 16 known pathogens. An etiological diagnosis was established in 80 (66%) of the 122 patients who participated in the study. The distribution of the etiological agents was as follows: influenza B virus in 27 (22%) patients. Chlamydia pneumoniae in 22 (18%), Legionella spp. in 15 (12%), Mycoplasma pneumoniae in 13 (11%), influenza A virus in 11 (9%), Bordetella pertussis in 9 (7%), adenovirus in 4, Epstein Barr virus in 4, Haemophilus influenzae in 3, beta-hemolytic streptococci in 3, Streptococcus pneumoniae in 2, respiratory syncytial virus in 2, parainfluenza 1 virus in 2 and parainfluenza 2 virus in 1. No patients were found to be infected with Coxiella burnetii, Moraxella catarrhalis or parainfluenza 3 virus. More than one pathogen was identified in 27 (34%) patients in whom an etiological diagnosis was established. It is concluded that RTI is caused by a broad spectrum of etiological agents, a considerable number of patients having evidence of infection with more than one pathogen. The therapeutic significance of these findings should be elucidated in further studies. 相似文献
993.
JL Forster DM Murray M Wolfson TM Blaine AC Wagenaar DJ Hennrikus 《Canadian Metallurgical Quarterly》1998,88(8):1193-1198
The aim of this in vitro study was to investigate the effect of troglitazone, a new oral antidiabetic agent, on LDL catabolism. HepG2 cells, which are cells from a well-differentiated cell line of hepatoma cells, were cultured and used to study LDL catabolism. Different concentrations of troglitazone, all within the therapeutic range for humans, were incubated in culture medium with 125I-labeled LDL to measure cell-associated and degraded 125I-LDL. Troglitazone increased cell-associated and degraded 125I-LDL by approximately 30%. We also investigated if this effect occurred through a LDL receptor-mediated pathway or a non-LDL receptor pathway. By using dextran sulfate, a substance known to release bound LDL from its receptor, we found that troglitazone upregulated LDL receptor activity by approximately 35%. In addition, we found that troglitazone increased the expression of the LDL receptor mRNA. The effect of troglitazone was comparable with that of a 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor, fluvastatin, with troglitazone having an upregulatory effect similar to that of fluvastatin. Insulin within human physiological concentrations also increased LDL receptor activity. We found that troglitazone and insulin had an additive effect on LDL catabolism. Also, the effect of troglitazone on LDL catabolism was studied in the presence of cyclosporine, an immunosuppressant drug that reduces LDL catabolism mainly by decreasing LDL receptor activity. The results showed that troglitazone can compensate for the reduced LDL receptor activity induced by cyclosporine, but that cyclosporine had a residual effect on the action of troglitazone. Thus troglitazone enhanced LDL binding, cell association, and degradation by increasing LDL receptor mRNA expression, with a subsequent increase in LDL receptor activity. 相似文献
994.
995.
LE Ferris H Barkun J Carlisle B Hoffman C Katz M Silverman 《Canadian Metallurgical Quarterly》1998,158(11):1473-1479
Ontario's Medical Expert Panel on Duty to Inform was formed to consider the duty of Ontario physicians in circumstances where a patient threatens to kill or cause serious bodily harm to a third party. The panel was concerned about the implications of any duty to inform on the integrity of the physician-patient relationship, particularly with respect to confidentiality. The panel agreed that regulations safeguarding the confidentiality of patient information ought to be changed only if there is a critical reason for doing so, but, after deliberation, the panel members concluded that the need to protect the public from serious risk of harm is a paramount concern that should supersede the duty of confidentiality. The recommendations reported here were endorsed in principle by the panelists and the groups they represented (the Royal College of Physicians and Surgeons of Canada, the Canadian Medical Protective Association, the College of Physicians and Surgeons of Ontario, the Ontario College of Family Physicians and the Ontario Medical Association) and are being implemented by the College of Physicians and Surgeons of Ontario. 相似文献
996.
M John T Pajak M Flam J Hoffman A Markoe H Wolkov K Paris 《Canadian Metallurgical Quarterly》1996,2(4):205-211
The synthesis of guanidinosuccinic acid (GSA) increases in uremics, and GSA is implicated as a uremic toxin. The GSA synthesis increases roughly in proportion to the serum urea level that increases in patients with renal failure. Urea is a specific inhibitor of argininosuccinase, the fourth urea cycle enzyme, and might lead to the increase of argininosuccinate (ASA). We found that GSA is formed from ASA by reactive oxygen species in vitro. In this paper, we investigated GSA synthesis from ASA in isolated rat hepatocytes and the effect of reactive oxygen species on this synthesis. When isolated rat hepatocytes were incubated with 5 mmol/l ASA, GSA was formed linearly with time up to 6 h (16 nmol/g wet liver/6 h). GSA was formed depending on the ASA concentration up to 10 mmol/l. Dimethylsulfoxide, a hydroxyl radical scavenger, inhibited GSA synthesis by 65%. GSA was actively formed when the hepatocytes were incubated with 32 mmol/l urea. The GSA formation in the presence of urea was also inhibited by dimethylsulfoxide, although the inhibition was less marked. FeCl2, that increases the hydroxyl radical generation, increased GSA synthesis. These results indicate that GSA is formed from ASA in isolated hepatocytes. The results also suggest that reactive oxygen species are important for GSA synthesis in the cells. 相似文献
997.
998.
Making Sense of Sensemaking 2: A Macrocognitive Model 总被引:3,自引:0,他引:3
999.
Patterson D. R.; Hoffman H. G.; Palacios A. Garcia; Jensen M. J. 《Canadian Metallurgical Quarterly》2006,115(4):834
The individual and combined effects of posthypnotic suggestion (PHS) and virtual reality distraction (VRD) on experimentally induced thermal pain were examined using a 2 × 2, between-groups design. After receiving baseline thermal pain, each participant received hypnosis or no hypnosis, followed by VRD or no VRD during another pain stimulus. Consistent with the hypothesis that hypnosis and VRD work via different mechanisms, results show that posthypnotic analgesia was moderated by hypnotizability but VRD analgesia was not. The impact of PHSs for analgesia was specific to high hypnotizables, whereas VRD was effective independent of hypnotizability. Results also show a nonsignificant but predicted pattern for high hypnotizables: Audio hypnosis combined with VRD reduced worst pain 22% more and pain unpleasantness 25% more than did VRD alone. Theoretical and clinical implications are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
1000.
In one of the earlier essays in this department, we discussed a number of acronyms all having to do with system design, and all having the form "x-centered design." The purpose of that essay was to demonstrate a broad framework within which to understand human-centered computing (HCC), and also to show the various convergences and divergences of the communities of practice that have introduced their own x-centered-design designations. Among them are learner-centered design, client-centered design, designer-centered design, decision-centered design, and work-oriented design. 相似文献