1,720,957 research outputs found
Fatal cardiac perforation and pulmonary embolism of leaked cement after percutaneous vertebroplasty
Full text linkPercutaneous vertebroplasty consists of percutaneous injection of polymethylmethacrylate (PMMA) via a transpedicular approach for the treatment of collapsed osteoporotic or metastatic vertebrae. Even if percutaneous vertebroplasty is considered to be minimally invasive, threatening complications can occur. Cement leakage is the most common complication of percutaneous vertebroplasty. Rigorous patient selection and individual therapeutic strategy may reduce the occurrence of leakage, in particular the risk of cement entry into the venous system and the spinal canal is the potent major hazard of this technique. Cement pulmonary and cardiac embolism are reported in literature as a cause of unexpected death after percutaneous vertebroplasty. Authors report a fatal case of pulmonary cement embolization occurred after vertebroplasty with haemopericardium, due to the perforation of the right atrium wall from a cement solidified fragment. A complete post mortem examination documented the presence of multiple cement fragments in the pulmonary arteries and transmural perforation of the wall of the right atrium by a whitish needle-like foreign body. Pulmonary microembolization was observed under polarized ligh
Hospital autopsy for prevention of sudden cardiac death
Full text linkIn the past 20 years, cardiovascular mortality has decreased in highincome countries in response to the adoption of preventive measures to reduce the burden of coronary artery disease and heart failure. Despite these encouraging results, cardiovascular diseases are responsible for approximately 17 million deaths every year in the world, approximately 25% of which are sudden cardiac death. The risk of sudden cardiac death is higher in men than in women, and it increases with age due to the higher prevalence of coronary artery disease in older age. Accordingly, the sudden cardiac death rate is estimated to range from 1.40 per 100 000 person-years in women to 6.68 per 100 000 person-years in men. Sudden cardiac death in younger individuals has an estimated incidence of 0.46–3.7 events per 100 000 person-years, corresponding to a rough estimate of 1100–9000 deaths in Europe and 800–6200 deaths in the USA every year.
Cardiac diseases associated with sudden cardiac death differ in young vs. older individuals. In the young there is a predominance of channelopathies and cardiomyopathies, myocarditis and substance abuse, while in older populations, chronic degenerative diseases predominate. In younger persons, the cause of sudden cardiac death may be elusive even after autopsy, because conditions such as inherited channelopathies or drug-induced arrhythmias that are devoid of structural abnormalities are epidemiologically relevant in this age group. Identification of the cause of an unexpected death provides the family with partial understanding and rationalization of the unexpected tragedy, which facilitates the coping process and allows an understanding of whether the risk of sudden death may extend to family members. Accordingly, author present their
experience with autopsies of unexplained sudden death young victims in which a cardiac origin was suspected and the relevance of a standardized protocol for heart examination and histological sampling, as well as for toxicology and molecular investigation
Autopsy as an outcome and performance measure: three years of hospital autopsy as an instrument of clinical audit
Full text linkAn extensive literature documents a high prevalence of errors in clinical diagnosis discovered at autopsy. Multiple studies have suggested no significant decrease in these errors over time. Despite these findings, autopsies have dramatically decreased in frequency in the United States and many other countries. In 1994, the last year for which national U.S. data exist, the autopsy rate for all non-forensic deaths fell below 6%. The marked decline in autopsy rates from previous rates of 40–50% undoubtedly reflects various factors, including reimbursement issues, the attitudes of clinicians regarding the utility of autopsies in the setting of other diagnostic advances, and general unfamiliarity with the autopsy and techniques for requesting it, especially among physicians-in-training. The autopsy is valuable for its role in undergraduate and graduate medical education, the identification and characterization of new diseases, and contributions to the understanding of disease pathogenesis. Although extensive, these benefits are difficult to quantify. This review of the last three years of hospital autopsy in Lucca studied the more easily quantifiable benefits of the autopsy as a tool in performance measurement and improvement. Such benefits largely relate to the role of the autopsy in detecting errors in clinical diagnosis and unsuspected complications of treatment. It is hoped that characterizing the extent to which the autopsy provides data relevant to clinical performance measurement and improvement will help inform strategies for preserving the benefits of routinely obtained autopsies and for considering its wider use as an instrument for quality improvement
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
- …
