1,720,985 research outputs found
Post-liver Transplantation Pancreatic Pseudocyst without Pancreatitis
Pancreatic pseudocysts rarely complicate acute pancreatitis after liver transplantation. We describe a case of post-transplant pancreatic pseudocyst occurring in the absence of pancreatitis.
A 53-year-old post-hepatitis C cirrhotic man with no history of pancreatic or biliary abnormalities underwent liver transplantation. However, at the time of surgery, a T-tube cholangiogram revealed a mild dilation of the native bile duct and, two months later, a large pancreatic pseudocyst was diagnosed and surgically resected. After two years, biochemical cholestasis developed and a liver biopsy showed biliary damage. ERCP revealed a stenosis of Vater’s papilla, which was successfully treated by sphincterotomy.
Pancreatic pseudocyst may arise as a complication of OLT in the absence of postoperative acute pancreatitis or a history of chronic pancreatitis. In our patient, it is suspected that ampullary dysfunction associated with ischemic pancreatic injury and bacterial infection played a role in generating both the early pancreatic pseudocyst and the late cholestasis
Going Beyond Counting First Authors in Author Co-citation Analysis
The 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
“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
We 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
We 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
Portal vein arterialization for hepatic artery thrombosis in liver transplantation : a case report, Doppler-ultrasound aspects, and review of the literature
Portal vein arterialization (PVA) is a salvage procedure for insufficient hepatic arterial or portal vascularization. It plays a role in auxiliary and orthotopic liver transplantation (OLT). In OLT, current indications for PVA include hepatic artery thrombosis (HAT), pre-OLT or post-OLT extended splanchnic vein thrombosis, intraoperative low portal flow, and anatomic variations like the absence of portal and mesenteric veins. Out of the transplantation domain, PVA is used both in extensive surgery for malignancies of the liver, biliary tract, and pancreas and in the treatment of fulminant hepatic failure (FHF) due to intoxications. We describe a case of acute post-OLT HAT successfully treated with PVA as a short bridge to retransplantation. By Doppler ultrasound of clinical PVA we detected an increased intrahepatic portal flow velocity, with disappearance of the arterial spikes, a finding that needs further investigation. PVA represents a rare surgical procedure. In fact, it has been used most of all in urgent conditions or in case of abrupt vascular complications during surgery. According to the literature, PVA emerges as a salvage procedure for poor arterial or portal hepatic flow, both in OLT and in general abdominal surgery. The outcome of this procedure is unpredictable. The aim of the shunt is to gain time, awaiting the onset of collateral arterial vessels or the performance of definitive surgery. Its early thrombosis may be a catastrophic event, due to acute liver ischemia. In contrast, a late occlusion is often well tolerated. Strict surveillance is always useful because sometimes it is mandatory to embolize the arterioportal fistula to treat or to prevent the onset of portal hypertension
Ultrasonography and hepatic involvement of early onset lymphoma after liver transplantation
Ultrasonography and hepatic involvment of earlyonset lymphoma after liver transplantation
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