Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 69
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Med Teach ; 33(4): 311-8, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21456989

RESUMO

BACKGROUND: E-learning has the potential to make important contributions to medical education, but there has been limited study of a blended approach in which the digital resources are introduced alongside traditional teaching methods such as lectures. METHODS: We describe the successful embedding of an e-learning resource into 3 of the 5 weeks of cardiovascular system teaching for 164 first-year medical students by providing scheduled slots in the timetables. A questionnaire completed by the students at the end of the 5 weeks had a response rate of 66%. Students varied in how they made use of the resource, some systematically working through it and others browsing and studying sections felt to be personally most relevant. RESULTS: Almost all (96%) rated the e-learning resources as probably or definitely of value: they particularly valued interactive activities, animations, video demonstrations, video clips of experts and self-assessment exercises. Graduate students had a significantly more favourable assessment of the e-learning resources than their undergraduate colleagues, while female students felt the value in supporting existing learning opportunities more strongly than male students. CONCLUSIONS: It should not be assumed that all students will choose to use an e-learning resource in the same way and instructional design should enable alternative approaches. The sequence in which the e-learning resource is used in relation to the other learning opportunities, such as lectures and PBL group discussions, may be important and merits further consideration. The experiences reported in this study provide encouragement and pointers for others engaged in the integration of e-learning in their curriculum.


Assuntos
Currículo , Faculdades de Medicina , Integração de Sistemas , Interface Usuário-Computador , Comportamento do Consumidor , Feminino , Humanos , Masculino , Estudantes de Medicina/psicologia , Inquéritos e Questionários
3.
Int J Lab Hematol ; 31(2): 142-50, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18177437

RESUMO

We report the first large-scale evaluation of the Hemochron Junior Signature (HJS) Microcoagulation System for community monitoring of oral anticoagulation and establishment of a programme of internal and external quality assurance. Over 1600 HJS results, with a simultaneous venous sample for central analysis, were obtained over a 19 month period. Monitoring of an initial period of HJS results (n = 135) revealed an International Normalized Ratio (INR) over estimation (mean +1.05), with only 27% of results within 0.5 of the central laboratory INR. A correction factor was introduced which reduced the INR bias to +0.07 and improved the percentage of results within 0.5 of the central laboratory INR to 76% (n = 353). A revised correction factor was later introduced to adjust for an under estimation at higher INR values. This changed the INR bias to -0.05, with 76% of results within 0.5 of the central laboratory INR (n = 1174). Local external quality assurance samples were distributed monthly with a total of 791 samples during the study period. 84% of test results were within 15% of the median value (range 73-97% per month). These results emphasize the value of a robust quality assurance programme when using point-of-care devices for community monitoring of oral anticoagulation.


Assuntos
Anticoagulantes/administração & dosagem , Testes de Coagulação Sanguínea/instrumentação , Monitoramento de Medicamentos/instrumentação , Sistemas Automatizados de Assistência Junto ao Leito , Varfarina/administração & dosagem , Administração Oral , Humanos , Coeficiente Internacional Normatizado/normas , Controle de Qualidade
5.
Leukemia ; 16(5): 785-90, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-11986938

RESUMO

The potential contribution of abnormal marrow stromal function to ineffective haemopoiesis in the myelodysplastic syndromes is unclear. We have compared the ability of stromal layers from normal (n = 7) and myelodysplastic (n = 9) marrow to alter proliferation and survival of the granulocyte-macrophage colony-stimulating factor/interleukin-3-dependent cell line F-36P. Co-cultures for 72 h in the absence of exogenous cytokines were either in direct contact with stroma or separated by transwell inserts. On normal stromal layers, the ratio of adherent F-36P cells relative to stromal cells increased from a mean of 0.2 +/- 0.01 (s.d.) at 4 h of co-culture to 0.34 +/- 0.08 after 72 h (n = 7). Corresponding values on myelodysplastic stroma (0.2 +/- 0.02 at 4 h and 0.35 +/- 0.05 at 72 h; n = 9) indicated that the ability of myelodysplastic stromal layers to regulate short-term proliferation of F-36P cells may be similar to normal. Apoptosis of F-36P cells was quantified after co-culture with normal or myelodysplastic stroma: results from myelodysplastic co-cultures were standardized as a fraction of values from co-cultures with paired normal stroma (apoptotic ratio). Augmented apoptosis of F-36P cells was detected in 8/9 co-cultures with myelodysplastic stroma (mean = 15.7 +/- 9.7%, n = 9), compared with corresponding normal stroma (mean = 12.4 +/- 4.6%, n = 7, P < 0.05) with a mean apoptotic ratio of 1.4 +/- 0.5 (P < 0.05). There was no correlation between stroma-related apoptosis and FAB type, tumour necrosis factor-alpha concentrations in the culture supernatant or numbers of stromal macrophages, and no evidence of involvement of the Fas pathway. Increased apoptosis was detected in cells grown in transwell inserts over stroma (23.8 +/- 3%, n = 5) compared to adherent cells in cultures with normal stromal layers, but this survival difference was not observed in co-cultures with myelodysplastic stroma. These results suggest that abnormal stromal function in patients with myelodysplastic syndromes may contribute to increased apoptosis of haemopoietic cells within the marrow microenvironment. The effect appears to be dependent on close cellular contact, rather than the release of soluble factors, but the exact mechanism remains unclear.


Assuntos
Células da Medula Óssea/patologia , Comunicação Celular , Síndromes Mielodisplásicas/patologia , Síndromes Mielodisplásicas/fisiopatologia , Células Estromais/patologia , Idoso , Apoptose , Estudos de Casos e Controles , Divisão Celular , Linhagem Celular , Sobrevivência Celular , Técnicas de Cocultura , Fator Estimulador de Colônias de Granulócitos e Macrófagos , Células-Tronco Hematopoéticas/citologia , Humanos , Interleucina-3
6.
Haematologica ; 86(10): 1038-45, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11602409

RESUMO

BACKGROUND AND OBJECTIVES: The regulation of hematopoiesis by marrow stroma in vitro, has been shown to be abnormal in some patients with myelodysplastic syndromes (MDS). This study was performed to assess whether a range of mechanisms may be altered within the MDS microenvironment. DESIGN AND METHODS: The effects of diffusible factors produced by normal or MDS stromal layers on hematopoietic cells were studied by comparing the ability of media conditioned (CM) by normal or MDS stroma to regulate migration of target normal marrow CD34+ cells across 5 microm transmembranes. The ability of CM to stimulate hematopoietic cells was also assessed: changes in membrane polarity of KG-1a cells on exposure to stroma CM were compared. Subsequently, contact-mediated interactions between normal marrow CD34+ cells and normal and MDS stroma were studied: survival of allogeneic normal marrow CD34+ cells on live and glutaraldehyde-fixed normal and myelodysplastic stroma after 24h of co-culture was measured using 7-aminoactinomycin D staining. To determine whether hematopoietic cell survival on normal and MDS stroma was related to oxidative stress within the stromal microenvironment, intracellular superoxide levels, both constitutively and induced by tumor necrosis factor-a were measured within live stromal cells by FACScan analysis of ethidium bromide stained cells. RESULTS: The ability of CM from normal and MDS stroma to regulate short-term migration and activation of hematopoietic cells was similar. The mean percentage of apoptotic CD34+ cells (13+/-11%) adherent to glutaraldehyde-fixed myelodysplastic stroma was higher than on paired fixed normal stroma (11+/-10%) (n=6, p=0.056). Constitutive mean levels of superoxide in myelodysplastic cultures (9.5+/-2.1) were greater than in normal stromal cultures (4.9+/-0.6; n=6). However, following treatment with tumor necrosis factor-a, the mean value for superoxide in myelodysplastic stromal cultures was unchanged (fractional change=0.99+/-0.56), compared with an increase in normal stroma (fractional change=1.6+/-0.1, p<0.05). No correlation was observed between superoxide levels, proportion of apoptotic CD34+ cells and percentage of CD14+ stromal cells [mean 8%, range 0-37% (myelodysplastic); mean 1.3%, range 0-5% (normal)]. INTERPRETATION AND CONCLUSIONS: Abnormalities of stromal function in myelodysplastic syndromes are likely to be heterogeneous in origin: altered matrix molecules and changes in superoxide within stromal cells may contribute to abnormal survival and development of hematopoietic cells within the myelodysplastic marrow microenvironment


Assuntos
Hematopoese , Síndromes Mielodisplásicas/patologia , Células Estromais/patologia , Células Estromais/fisiologia , Idoso , Idoso de 80 Anos ou mais , Células da Medula Óssea/patologia , Células da Medula Óssea/fisiologia , Técnicas de Cultura de Células , Meios de Cultivo Condicionados/farmacologia , Células-Tronco Hematopoéticas/efeitos dos fármacos , Células-Tronco Hematopoéticas/metabolismo , Células-Tronco Hematopoéticas/fisiologia , Humanos , Pessoa de Meia-Idade , Superóxidos/metabolismo
7.
Clin Lab Haematol ; 23(2): 119-24, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11488851

RESUMO

The pattern of emergence of multipotential (CFU-A) and committed (CFU-GM and BFU-E) progenitor cells in peripheral blood has been examined in patients with Hodgkin's disease and non-Hodgkin's lymphoma. Mobilization protocols used chemotherapy with or without granulocyte colony-stimulating factor (n=8 and n=5, respectively). In all patients, the numbers of CFU-A, CFU-GM and BFU-E peaked simultaneously, rather than sequentially, suggesting that marrow regeneration after these mobilization protocols occurred from progenitors at all stages of differentiation. We conclude that peripheral blood stem cell harvest strategies based on peak values for total progenitor numbers will also capture maximum numbers of multipotential progenitors. However, the variable relationship between CFU-A and CFU-GM numbers suggests that overall progenitor cell numbers can give only a broad estimate of the absolute numbers of multipotential progenitors in an individual harvest.


Assuntos
Células-Tronco Hematopoéticas/patologia , Doença de Hodgkin/patologia , Linfoma não Hodgkin/patologia , Adulto , Idoso , Feminino , Hematopoese , Mobilização de Células-Tronco Hematopoéticas , Doença de Hodgkin/sangue , Humanos , Linfoma não Hodgkin/sangue , Masculino , Pessoa de Meia-Idade , Fatores de Tempo
8.
Med Teach ; 23(4): 357-366, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12098382

RESUMO

The introduction of an outcome-based approach to education at Dundee Medical School in Scotland instigated a search for assessment methods that would appropriately assess the students' achievements in terms of the learning outcomes. Portfolio assessment has been developed for this purpose and has been adopted for the summative assessment of students in their final examination in Dundee. The contents of the portfolio and the assessment process have been defined and the first cohort of students to be assessed in this way has been studied. The evaluation of the approach demonstrated strong staff support. Students were also positive although with some reservations. It is concluded that portfolio assessment is a powerful approach to assessing a range of curriculum outcomes not easily assessed by other methods and is worthy of inclusion in the assessor's toolkit.

9.
Med Teach ; 23(6): 535-551, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12098472

RESUMO

This guide is intended to inform medical teachers about the use of portfolios for student assessment. It provides a background to the topic, reviews the range of assessment purposes for which portfolios have been used, identifies possible portfolio contents and outlines the advantages of portfolio assessment with particular focus on assessing professionalism. The experience of one medical school, the University of Dundee, is presented as a case study. The current state of understanding of the technical, psychometric issues relating to portfolio assessment is clarified. The final part of the paper provides a practical guide for those wishing to design and implement portfolio assessment in their own institutions. Five steps in the portfolio assessment process are identified: documentation, reflection, evaluation, defence and decision. It is concluded that portfolio assessment is an important addition to the assessor's toolkit. Reasons for using portfolios for assessment purposes include the impact that they have in driving student learning and their ability to measure outcomes such as professionalism that are difficult to assess using traditional methods.

13.
J Clin Pathol ; 51(1): 73-4, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9577377

RESUMO

Genetic testing for hereditary haemochromatosis is likely to be a significant workload for diagnostic laboratories. The C282Y and H63D mutations in the HFE gene associated with hereditary haemochromatosis have previously been detected using a number of methods including alterations in the restriction digest pattern of polymerase chain reaction (PCR) amplified products. An amplification refractory mutation system (ARMS) has been developed that will simultaneously detect both hereditary haemochromatosis mutations. Comparison of the results obtained from the analysis of 46 samples referred for hereditary haemochromatosis testing showed no discrepancies between ARMS and restriction enzyme digestion. Furthermore, consistent results were obtained by ARMS from both blood and buccal mouthwash samples. The ARMS test is quicker and less expensive in terms of consumables and scientist time than restriction enzyme analysis, and is therefore suited to the routine diagnostic analysis of hereditary haemochromatosis.


Assuntos
Cromossomos Humanos Par 6 , Genes MHC Classe I/genética , Hemocromatose/genética , Mutação Puntual , Bochecha/patologia , Análise Mutacional de DNA/métodos , Hemocromatose/diagnóstico , Humanos , Reação em Cadeia da Polimerase , Mapeamento por Restrição , Irrigação Terapêutica
14.
Clin Nephrol ; 48(1): 1-8, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9247771

RESUMO

Much progress has been made in recent years in the management of anemia associated with chronic and renal failure with recombinant human erythropoietin (r-Hu EPO). However, there remains much debate surrounding the diagnosis and treatment of iron deficiency. To ensure that full benefit from erythropoietin therapy is received, most patients require iron supplement during treatment. There are, however, few guidelines for the use of iron therapy. Iron deficiency results in an inadequate response to r-Hu EPO and is the main cause of resistance to this treatment. Oral iron therapy is of limited value in patients receiving r-Hu EPO. Thus, intravenous iron supplementation should be administered only in patients who do not tolerate available intravenous iron preparations or who are on continuous ambulatory peritoneal dialysis with no evidence of functional iron deficiency. This article provides guidelines for the diagnosis of absolute or functional iron deficiency in patients with renal anemia and suggests treatment schedules for intravenous iron supplementation. We hope that all dialysis patients will be able on this basis to achieve a satisfactory iron status and benefit fully from r-Hu EPO therapy.


Assuntos
Anemia Ferropriva/tratamento farmacológico , Anemia/tratamento farmacológico , Eritropoetina/uso terapêutico , Ferro/uso terapêutico , Falência Renal Crônica/complicações , Anemia/etiologia , Anemia Ferropriva/etiologia , Ferritinas/sangue , Humanos , Infusões Intravenosas , Ferro/administração & dosagem , Falência Renal Crônica/terapia , Diálise Peritoneal Ambulatorial Contínua , Proteínas Recombinantes/uso terapêutico , Diálise Renal
18.
Br J Haematol ; 82(2): 445-54, 1992 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1419827

RESUMO

The effects on iron absorption of variation in erythroid activity, haemoglobin and iron stores were studied in six anaemic dialysis-dependent subjects in whom iron stores were increased from previous red cell transfusions. Gastrointestinal mucosal uptake and whole body retention of oral iron were measured at the beginning of the study, after starting treatment with recombinant erythropoietin (but before significant increase in haemoglobin), after partial correction of anaemia, after further reduction of iron stores by repeated phlebotomy, and when erythropoiesis decreased from the discontinuation of treatment with erythropoietin. Between successive measurements, valid comparisons were made in five subjects. Correction of anaemia decreased whole body retention of iron through decreased mucosal uptake (P = 0.032). Further reduction in iron stores through repeated phlebotomy whilst the increase in haemoglobin was maintained by treatment with erythropoietin, tended to increase whole body retention of iron through an increase in mucosal transfer (P = 0.010). With initial enhancement of erythropoiesis in anaemic iron-loaded subjects there was no change in any measured component of iron absorption. However, after correction of anaemia and reduction of iron stores, a decrease in erythropoiesis was associated with decreased whole body iron retention in all subjects through decreased mucosal transfer (P = 0.028). The data suggest that anaemia upregulates mucosal iron uptake, and that erythroid activity upregulates mucosal transfer but that this latter effect may be counter-balanced by iron overload which downregulates mucosal transfer.


Assuntos
Eritropoetina/uso terapêutico , Ferro/farmacocinética , Falência Renal Crônica/metabolismo , Proteínas Recombinantes/uso terapêutico , Adulto , Transfusão de Sangue , Sangria , Eritropoese/efeitos dos fármacos , Feminino , Ferritinas/análise , Hemoglobinas/análise , Humanos , Absorção Intestinal/efeitos dos fármacos , Ferro/sangue , Falência Renal Crônica/terapia , Masculino , Pessoa de Meia-Idade , Diálise Renal , Fatores de Tempo
20.
J Intern Med ; 230(4): 361-2, 1991 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1919430

RESUMO

A 64-year-old lady with a personal and family history of autoimmune disease developed chronic myelomonocytic leukaemia and multiple myeloma simultaneously. Her sister died of acute myelomonocytic leukaemia, but showed no evidence of autoimmune disease. It is possible that chronic immunological stimulation, perhaps by an autoantigen, may predispose toward malignant transformation in both plasma cell and monocyte series. However, the present observations raise the alternative possibility of a primary disorder of monocytes that predisposes toward both autoimmune disease and a clonal disorder of plasma cells.


Assuntos
Doenças Autoimunes/complicações , Leucemia Mielomonocítica Crônica/imunologia , Mieloma Múltiplo/imunologia , Neoplasias Primárias Múltiplas/imunologia , Feminino , Humanos , Pessoa de Meia-Idade
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...