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Objectives Curriculum reform poses significant challenges for medical schools across the globe. Understanding the medical educator’s personal and lived experience of curriculum change is paramount. This paper illustrates the use of narrative inquiry as a means of exploring the author’s own evolving professional identity as a medical educator engaged in planning and leading curriculum reform and in understanding the meanings she and other medical educators attribute to their roles as agents of change in a medical school. Context In 2002 it was decided to radically reform a school of medicine’s (SoM) traditional 6‐year medical degree course (converting it to a 5‐year, integrated, case‐based programme). This followed a decade of adverse external reports by the national accreditation agency. The 2001 accreditation report was the most significant catalyst for change, and drew attention to the School’s need for a ‘collective will’ to introduce a series of specific curriculum reforms. To support this reform, a new curriculum working group (NCWG) supported by a dedicated medical education unit (MEU) was established. In late 2002 the author joined the School as the director of that unit. Methods This paper draws on a 3‐year study which captured the stories of the curriculum planning project between 2002 and 2005, as well as stories of curriculum reform from past deans of the same medical school dating back to 1965. Narrative inquiry is used as a means of probing the author’s own lived experience as coordinator of the new curriculum project and the experiences of key members of the NCWG, including the dean, and of former deans from the same medical school over its 40‐year history. Conclusions Through a living, telling and retelling of the story of curriculum change, narrative inquiry has a role to play in both elucidating the individual lived experience of curriculum change and shaping the evolving professional identity of the medical educator as an agent of change.  相似文献   
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Preparing a medical school for institutional review can be a challenging undertaking for any institution requiring an understanding of the international standards being used and adequate preparation and planning (MacCarrick et al. in Med Teach 32(5):e227–e232, 2010). This series examines each of the nine standards developed by the World Federation for Medical Education (WFME in Basic Medical Education: Global Standards for Quality Improvement, University of Copenhagen Denmark, 2003) with practical advice on their use in both self-review and independent accreditation processes. The WFME standards and their purpose are described and the use of these standards to ‘drive’ the quality improvement agenda in undergraduate medical education is also discussed.  相似文献   
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A cross sectional study was done between October 1999 and February 2000 to determine antimicrobial susceptibility patterns of consecutive bacterial isolates of 102 clinical samples among surgical in-patients at Lilongwe Central Hospital (LCH), Malawi. Antimicrobial susceptibility was determined using comparative disc diffusion techniques. 83 (81.4%) samples were culture positive for bacterial growth while 19 (18.6%) grew nothing. Of the 93 culture positive specimens, Staphylococcus aureus was the predominant organism 43(51.8%) followed by Proteus species 8(9.6%) and E. coli 7(8.4%). Overall, 98.6% of all isolates tested against ciprofloxacin were susceptible, and against gentamicin and flucloxacin were 84.8% and 66.7% respectively. 59.3% of isolates tested against chloramphenicol were resistant. We recommend a review on the use of chloramphenicol as first-line antimicrobial therapy among surgical in-patients at Lilongwe Central Hospital. We also recommend restricted use of antimicrobials so as to minimise development of drug resistance. Periodic susceptibility studies are necessary to guide judicious use of antibiotics.  相似文献   
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Erythropoietin kinetics in rats: generation and clearance   总被引:1,自引:0,他引:1  
Steinberg  SE; Garcia  JF; Matzke  GR; Mladenovic  J 《Blood》1986,67(3):646-649
Detailed studies to analyze the early events of erythropoietin (Ep) secretion and clearance were performed in a rat model using a double antibody radioimmunoassay. Ep clearance was determined following intravenous injection of 1 mL of Ep-rich plasma, 1,080 mU/mL, obtained from phlebotomized rats. Analysis revealed a disappearance curve that conformed to a two-compartment model with an alpha half-life t1/2 of 3.6 minutes and a beta t1/2 of 86 minutes. The volume of distribution was similar to the calculated plasma volume. In anephric animals, there was no change in the plasma clearance rate or the volume of distribution. Rapid Ep secretion was elicited by a single 15 mL/kg phlebotomy (hematocrit decrement 45% to 30%), so that levels reached 20 to 30 times baseline (524 +/- 76 v 24 +/- 7 mU/mL) at five hours, whereas they plateaued for at least 33 hours. The increase in the rate of secretion was geometric, from 9.9 mU/h baseline secretion to 429 mU/h. These data identify a very sensitive and rapidly responsive system for Ep modulation in the rat.  相似文献   
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There is a long-standing controversy as to whether a single bone marrow (BM)-derived cell can differentiate along both hematopoietic and stromal lineages. Both primitive hematopoietic and stromal progenitor cells in human BM express the CD34 antigen but lack expression of other surface markers, such as CD38. In this study we examined the CD34+, CD38- fraction of human fetal BM by multiparameter fluorescence- activated cell sorting (FACS) analysis and single-cell sorting. CD34+, C38- cells could be divided into HLA-DR+ and HLA-DR- fractions. After single-cell sorting, 59% of the HLA-DR+ cells formed hematopoietic colonies. In contrast, the CD34+, CD38-, HLA-DR- cells were much more heterogeneous with respect to their light scatter properties, expression of other hematopoietic markers (CD10, CD36, CD43, CD49b, CD49d, CD49e, CD50, CD62E, CD90w, CD105, and CD106), and growth properties. Single CD34+, CD38-, HLA-DR- cells sorted into individual culture wells formed either hematopoietic or stromal colonies. The presence or absence of CD50 (ICAM-3) expression distinguished hematopoietic from stromal progenitors within the CD34+, CD38-, HLA-DR- population. The CD50+ fraction had light scatter characteristics and growth properties of hematopoietic progenitor cells. In contrast, the CD50- fraction lacked hematopoietic progenitor activity but contained clonogenic stromal progenitors at a mean frequency of 5%. We tested the hypothesis that cultures derived from single cells with the CD34+, CD38- , HLA-DR- phenotype could differentiate along both a hematopoietic and stromal lineage. The cultures contained a variety of mesenchymal cell types and mononuclear cells that had the morphologic appearance of histiocytes. Immunophenotyping of cells from these cultures indicated a stromal rather than a hematopoietic origin. In addition, the growth of the histiocytic cells was independent of the presence or the absence of hematopoietic growth factors. Based on sorting more than 30,000 single cells with the CD34+, CD38-, HLA-DR- phenotype into individual culture wells, and an analysis of 864 stromal cultures initiated by single CD34+ BM cells, this study does not support the hypothesis of a single common progenitor for both hematopoietic and stromal lineages within human fetal BM.  相似文献   
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ABSTRACT: The number of people with diabetes and pre-diabetes are exponentially increasing. Studies on humans have shown the beneficial effects of Zinc supplementation in patients with diabetes. The present study aims to systematically evaluate the literature and meta-analyze the effects of Zinc supplementation on diabetes. A systematic review of published studies reporting the effects of Zinc supplementations on diabetes mellitus was undertaken. The literature search was conducted in the following databases; PubMed, Web of Science and SciVerse Scopus. A meta-analysis of studies examining the effects of Zinc supplementation on clinical and biochemical parameters in patients with diabetes was performed. The total number of articles included in the present review is 25, which included 3 studies on type-1 diabetes and 22 studies on type-2 diabetes. There were 12 studies comparing the effects of Zinc supplementation on fasting blood glucose in patients with type-2 diabetes. The pooled mean difference in fasting blood glucose between Zinc supplemented and placebo groups was 18.13mg/dl (95%CI:33.85,2.41; p<0.05). 2-h post-prandial blood sugar also shows a similar distinct reduction in (34.87mg/dl [95%CI:75.44; 5.69]) the Zinc treated group. The reduction in HbA1c was 0.54% (95%CI:0.86;0.21) in the Zinc treated group. There were 8 studies comparing the effects of Zinc supplementation on lipid parameters in patients with type-2 diabetes. The pooled mean difference for total cholesterol between Zinc supplemented and placebo groups was 32.37mg/dl (95%CI:57.39,7.35; p<0.05). Low-density lipoprotein cholesterol also showed a similar distinct reduction in the Zinc treated group, the pooled mean difference from random effects analysis was 11.19mg/dl (95%CI:21.14,1.25; p<0.05). Studies have also shown a significant reduction in systolic and diastolic blood pressures after Zinc supplementation. This first comprehensive systematic review and meta-analysis on the effects of Zinc supplementation in patients with diabetes demonstrates that Zinc supplementation has beneficial effects on glycaemic control and promotes healthy lipid parameters. Further studies are required to identify the exact biological mechanisms responsible for these results.  相似文献   
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