1,721,014 research outputs found
Hamartoma of mature cardiomyocytes presenting with atypical angina, 18F-fluorodeoxyglucose positron emission tomography uptake, and myocardial bridging: a case report
Full text linkAim
Hamartoma of mature cardiomyocytes is a rare tumor and the present case shows a complex diagnostic pathway to understand its nature and treatment options in a young patient. The myocardial bridge was also part of the clinical evaluation discovered during the diagnostic workout.
Methods and results
A 27-year-old woman with atypical chest pain and a normal electrocardiogram received the diagnosis of neoformation of the interventricular septum with 18F-fluorodeoxyglucose (18F-FDG) uptake, and evidence of myocardial bridging on coronary angiography. On suspicion of malignancy, coronary unroofing and surgical biopsy was performed. The final diagnosis was hamartoma of mature cardiomyocytes.
Conclusion
This case offers great insight into medical reasoning and decision-making process. Given the history of chest pain, the patient was evaluated for possible ischemic, embolic, or vascular causes. Given a left ventricular wall thickness ≥15 mm, hypertrophic cardiomyopathy (HCM) should always be suspected; nuclear magnetic resonance imaging is essential to distinguish between HCM. The magnetic resonance imaging is also critical in distinguishing HCM itself from tumoral phenocopies. To rule out a neoplastic process, 18F-FDG positron emission tomography (PET) was used. A surgical biopsy was performed, and the final diagnosis was completed after the immune-histochemistry study. A myocardial bridge was found during preoperative coronagraphy and was treated accordingly.
Hamartoma of mature cardiomyocytes is a rare tumor and the present case shows a complex diagnostic pathway to understand its nature and treatment options in a young patient. The myocardial bridge was also part of the clinical evaluation discovered during the diagnostic workout.
Methods and results
A 27-year-old woman with atypical chest pain and a normal electrocardiogram received the diagnosis of neoformation of the interventricular septum with 18F-fluorodeoxyglucose (18F-FDG) uptake, and evidence of myocardial bridging on coronary angiography. On suspicion of malignancy, coronary unroofing and surgical biopsy was performed. The final diagnosis was hamartoma of mature cardiomyocytes.
Conclusion
This case offers great insight into medical reasoning and decision-making process. Given the history of chest pain, the patient was evaluated for possible ischemic, embolic, or vascular causes. Given a left ventricular wall thickness ≥15 mm, hypertrophic cardiomyopathy (HCM) should always be suspected; nuclear magnetic resonance imaging is essential to distinguish between HCM. The magnetic resonance imaging is also critical in distinguishing HCM itself from tumoral phenocopies. To rule out a neoplastic process, 18F-FDG positron emission tomography (PET) was used. A surgical biopsy was performed, and the final diagnosis was completed after the immune-histochemistry study. A myocardial bridge was found during preoperative coronagraphy and was treated accordingly
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Occult primary cardiac lymphomas causing unexpected/sudden death or acute heart failure
No full textThree cases of unexpected/sudden death (N = 2) or acute heart failure (N = 1) were investigated in our centre. The first patient died unexpectedly after surgery for cardiac tamponade and constrictive pericarditis; at autopsy, gross features mimicked a pericardial mesothelioma. The second patient died suddenly after recovering from a respiratory insufficiency episode; autopsy revealed an epicardial mass encircling the right coronary artery. The third patient presenting symptoms mimicked a fulminant myocarditis and she underwent endomyocardial biopsy. In all cases, histology disclosed a diffuse large B cell non-Hodgkin lymphoma, localized to the pericardium together with the right ventricle and the conduction system, to the epicardium and the right coronary artery or to the myocardium, respectively. Histology was crucial for the diagnosis, the atypical presentation favouring other diagnostic hypotheses. Although primary cardiac lymphoma is uncommon and usually shows a sub-acute onset, it may also cause unexpected/sudden death or acute heart failure
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