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21.
Jacinta E. Browne Louise M. Cannon Ronan McDermott Max Ryan Andrew J. Fagan 《Ultrasound in medicine & biology》2017,43(11):2733-2740
A device for the training and quantitative assessment of the competency of trainee radiologists in the technically challenging area of breast sonography was developed and evaluated. Currently, suitable commercially available devices are lacking, and there is a growing realization that the reliance on direct exposure to patients for learning may not represent best practice from either the trainees' or patients' perspective. Three devices (PI, PII and PIII) were designed to produce very realistic sonographic images of breast morphology with a range of embedded pathologies. The pilot evaluation used a case study research design to evaluate the role of the anthropomorphic breast sonography training device in training and assessment in a clinical environment. Through the case study, it was possible to evaluate the process and relationships when using this type of training intervention for a small group of radiology resident trainees. The investigation involved a baseline assessment of trainees' (n = 4) ability to detect and characterize all lesions in PI, followed by a 4-wk training period on PII and a post-training assessment using PIII. The evaluation revealed an improvement of 30% ± 8% in the trainee's performance from pre- to post-training. It was expected that the performance of the trainees would improve as the training phantom described in this study aligns with the learning theory of constructivism and fits the ideal specifications of a medical training device in terms of its realism and facilitation of self-directed learning and deliberate practice of the trainees. The device provides a useful platform upon which training and assessment can be facilitated. 相似文献
22.
Timothy Ronan Leahy Eyal Cohen Upton D Allen 《The Canadian Journal of Infectious Diseases & Medical Microbiology》2012,23(3):137-139
A three-year-old boy presented with community-acquired pneumonia complicated by empyema. Streptococcus pyogenes (group A streptococcus) was identified on culture of the pleural fluid. The patient improved with antibiotic therapy and drainage of the empyema.During his convalescence, the patient developed persistent fever, lethargy and anorexia. His inflammatory markers were elevated, and repeat cultures were negative. Although the patient had none of the classical mucocutaneous features of Kawasaki disease, an echocardiogram was performed, which revealed coronary artery dilation.The patient was diagnosed with incomplete Kawasaki disease and treated with intravenous immunoglobulin and high-dose acetylsalicylic acid. The fever subsided within 48 h.To the authors’ knowledge, the present report is the first report of Kawasaki disease associated with complicated S pyogenes pneumonia. It emphasizes the importance of considering incomplete Kawasaki disease among children with persistent fever, the role of echocardiography in diagnosis, and the potential link between Kawasaki disease and superantigen-producing organisms such as S pyogenes. 相似文献
23.
K Michielsen R Beauclair W Delva K Roelens R Van Rossem M Temmerman 《BMC public health》2012,12(1):729
ABSTRACT: BACKGROUND: While the HIV epidemic is levelling off in sub-Saharan Africa, it remains at an unacceptably high level. Young people aged 15-24 years remain particularly vulnerable, resulting in a regional HIV prevalence of 1.4% in young men and 3.3% in young women. This study assesses the effectiveness of a peer-led HIV prevention intervention in secondary schools in Rwanda on young people's sexual behavior, HIV knowledge and attitudes. METHODS: In a non-randomized longitudinal controlled trial, fourteen schools were selected in two neighboring districts: Bugesera (intervention) and Rwamagana (control). Students (n = 1950) in eight intervention and six control schools participated in three surveys (baseline, six and twelve months in the intervention). Analysis was done using linear and logistic regression using generalized estimation equations adjusted for propensity score. RESULTS: The overall retention rate was 72%. Time trends in sexual risk behavior (being sexually active, sex in last six months, condom use at last sex) were not significantly different in students from intervention and control schools, nor was the intervention associated with increased knowledge, perceived severity or perceived susceptibility. It did significantly reduce reported stigma. CONCLUSIONS: Analyzing this and other interventions, we identified several reasons for the observed limited effectiveness of peer education: 1) intervention activities (spreading information) are not tuned to objectives (changing behavior); 2) young people prefer receiving HIV information from other sources than peers; 3) outcome indicators are not adequate and the context of the relationship in which sex occurs. Effectiveness of peer education may increase through integration in holistic interventions and redefining peer educators' role as focal points for sensitization and referral to experts and services. Finally, we argue that a narrow focus on sexual risks will never significantly turn the tide. 相似文献
24.
The development of targeted agents for metastatic esophageal or gastroesophageal junction (GEJ) tumors has been limited when compared with that for other common tumors. To date, the anti‐human epidermal growth factor receptor‐2 (HER‐2) antibody, trastuzumab, in combination with chemotherapy, is the only approved novel agent for these cancers, and its use is limited to the small population of patients whose tumors overexpress HER‐2. Despite recent progress in the field, median overall survival remains only 8–12 months for patients with stage IV esophageal or GEJ cancer. In this article, we examine the molecular aberrations thought to drive the development and spread of esophageal cancer and identify promising targets for specific tumor inhibition. Data from clinical studies of targeted agents are reviewed, including epidermal growth factor receptor antibodies, tyrosine kinase inhibitors, HER‐2, and vascular endothelial growth factor‐directed therapy. Current and future targets include MET, fibroblast growth factor receptor, and immune‐based therapies. Evidence from trials to date suggests that molecularly unselected patient cohorts derive minimal benefit from most target‐specific agents, suggesting that future collaborative investigation should focus on preselected molecular subgroups of patients with this challenging heterogeneous disease. 相似文献
25.
26.
Human Parathyroid Hormone: Amino-Acid Sequence of the Amino-Terminal Residues 1-34 总被引:6,自引:3,他引:6
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H. B. Brewer Jr. T. Fairwell R. Ronan G. W. Sizemore C. D. Arnaud 《Proceedings of the National Academy of Sciences of the United States of America》1972,69(12):3585-3588
Human parathyroid hormone has been isolated in highly purified form from human parathyroid adenomas. The primary sequence of the amino-terminal 34 residues of the human hormone was obtained by automated degradation with a Beckman Sequencer. The phenylthiohydantoin amino acids were identified by gas chromatography and mass spectrometry. The first 34 residues of human parathyroid hormone differ from the bovine hormone by six residues, and from the porcine hormone by five residues. The amino-terminal residue is serine, similar to the porcine parathyroid hormone; bovine parathyroid hormone contains an amino-terminal alanine. Human parathyroid hormone contains two methionine residues, similar to the bovine species, whereas porcine parathyroid hormone contains a single methionine residue. Amino-acid residues in the first 34 that are unique to the human sequence include an asparagine at position 16, glutamine at position 22, lysine at position 28, and a leucine at position 30. 相似文献
27.
Ronan Roussel Pierre G. Carlier Jean-Jacques Robert Gilberto Velho Gilles Bloch 《Proceedings of the National Academy of Sciences of the United States of America》1998,95(3):1313-1318
The muscle intracellular (IC) free glucose concentration and the rate of muscle glycogen synthesis were measured by using in vivo 13C and 31P NMR spectroscopy in normal volunteers under hyperinsulinemic (≈300 pM) clamp conditions at the following three plasma glucose levels: euglycemia (≈6 mM), mild (≈10 mM), and high (≈16 mM) hyperglycemia. In keeping with biopsy studies, muscle IC free glucose concentration at euglycemia (−0.03 ± 0.03 mmol/kg of muscle, mean ± SEM, n = 10) was not statistically different from zero. A small but statistically significant amount of IC free glucose was observed during mild and high hyperglycemia: 0.15 ± 0.08 (n = 5) and 0.43 ± 0.20 mmol/kg of muscle (n = 5), respectively. Muscle glycogen synthesis rate, in mmol per kg of muscle per min, was 111 ± 11 at euglycemia (n = 10), 263 ± 29 during mild hyperglycemia (n = 5), and 338 ± 42 during high hyperglycemia (n = 5), these three rates being significantly different from each other. As previous in vitro and in vivo studies, these rates suggest a Km (concentration at which unidirectional glucose transport reaches half-maximal rate) of the muscle glucose transport system in the 15–25 mM range under hyperinsulinemic conditions. The low concentrations of muscle IC free glucose observed under hyperinsulinemic conditions were interpreted, with this estimate and in the framework of metabolic control theory, as glucose transport being the predominant step controlling muscle glucose flux not only at euglycemia but also during hyperglycemia. 相似文献
28.
Bright I Nwaru Mome Mukherjee Ramyani P Gupta Angela Farr Martin Heaven Andrew Stoddart Amrita Bandyopadhyay Deborah Fitzsimmons Michael Shields Ceri Phillips George Chamberlain Colin Fischbacher Christopher Dibben Chantelle Aftab Colin R Simpson Ronan Lyons David Strachan Gwyneth A Davies Brian McKinstry Aziz Sheikh 《Journal of the Royal Society of Medicine》2015,108(11):433-439
29.
Update on magnetic resonance cholangiopancreatography 总被引:2,自引:0,他引:2
MRCP is a useful tool in the diagnosis of a wide variety of pathologic entities including congenital anomalies, biliary obstruction and stricture, biliary calculi, pancreatitis, neoplasms, and trauma. ERCP and MRCP both have important roles in the management of patients with suspected pancreaticobiliary disease. Knowledge of the advantages and disadvantages of each technique is needed to determine the appropriate work-up of patients with these pathologies. 相似文献
30.
Turner S Iliffe S Downs M Wilcock J Bryans M Levin E Keady J O'Carroll R 《Age and ageing》2004,33(5):461-467
OBJECTIVE: To measure general practitioners' knowledge of, confidence with and attitudes to the diagnosis and management of dementia in primary care. SETTING: 20 general practices of varying size and prior research experience in Central Scotland, and 16 similarly varied practices in north London. Participants: 127 general practitioners who had volunteered to join a randomised controlled trial of educational interventions about dementia diagnosis and management. METHODS: Self-completion questionnaires covering knowledge, confidence and attitudes were retrieved from practitioners prior to the educational interventions. RESULTS: General practitioners' knowledge of dementia diagnosis and management is good, but poor awareness of its epidemiology leads to an over-estimate of caseload. Knowledge of local diagnostic and support services is less good, and one third of general practitioners expressed limited confidence in their diagnostic skills, whilst two-thirds lacked confidence in management of behaviour and other problems in dementia. The main difficulties identified by general practitioners were talking with patients about the diagnosis, responding to behaviour problems and coordinating support services. General practitioners perceived lack of time and lack of social services support as the major obstacles to good quality care more often than they identified their own unfamiliarity with current management or with local resources. Attitudes to the disclosure of the diagnosis, and to the potential for improving the quality of life of patients and carers varied, but a third of general practitioners believed that dementia care is within a specialist's domain, not that of general practice. More experienced and male general practitioners were more pessimistic about dementia care, as were general practitioners with lower knowledge about dementia. Those reporting greater difficulty with dementia diagnosis and management and those with lower knowledge scores were also less likely to express attitudes endorsing open communication with patient and carer. CONCLUSION: Educational support for general practitioners should concentrate on epidemiological knowledge, disclosure of the diagnosis and management of behaviour problems in dementia. The availability and profile of support services, particularly social care, need to be enhanced, if earlier diagnosis is to be pursued as a policy objective in primary care. 相似文献