1,720,958 research outputs found
Familial colorectal cancer: a concept revisited
No full textOBJECTIVE: The family history of patients with colorectal cancer (CRC) shows an increased risk of disease although evident inherited syndromes are demonstrable in only a small percentage of patients. The purpose of this study was to identify factors that might suggest an inherited component in the transmission of CRC.
METHOD: The study monitored 880 consecutive patients between 1980 and 2005 treated for CRC.
RESULTS: Familial adenomatous polyposis (FAP) was found in only one patient, and a classical mutation of hereditary nonpolyposis colon cancer was found in only two patients. The risk assessment was possible mainly because of factors such as early onset CRC, the presence of multiple primary tumours and a high risk family history. Considering these 36 more patients were suspected to be high risk and referred for further genetic testing. At least one first-degree relative with CRC was reported in 140 patients. In 49 patients, CRC was diagnosed before 50 years of age. Multiple primary tumours, colonic or extra colonic, synchronous or metachronous were found in 136 patients.
CONCLUSION: Our study suggests that if only patients with identified mutations are taken into consideration, then the percentage of evident hereditary colon cancer is very low, but this percentage quickly increases if we make marginal adjustments to the identifying criteria. It seems that it is the physician's clinical suspicion, more than the fulfillment of rigid criteria, which plays a fundamental role in the timely identification and a subsequent focused treatment of patients with hereditary CR
Renal transplant from very old donors: how far can we go?
No full textThe organ shortage has led many transplant centers to accept kidneys from old, suboptimal deceased donors, and make increasing use of old-for-old allocation systems. We report the experience of an Italian transplant center in the utilization of "ultra-old" (>75 years old) donors.
Methods. Sixty grafts from donors aged 75 years or older (mean age 79.1 years, range 75-90 years) were used for 38 patients: 16 as single and 22 as double transplants.
Results. The actuarial graft survival rate was 73.7% for year 1, 69.8% for year 2, and 64.0% for year 3. The patient survival rate was 81.2% and remained stable for years 1, 2, and 3. The delayed graft function rate was 57.9%. Acute rejection and chronic allograft nephropathy rates were comparable with our other expanded criteria donors. The majority of the patients had stable creatinine levels, between 2 and 3 mg/mL after the second month, with sufficient creatinine clearance.
Conclusions. Our results seems encouraging with patient and graft survival rates, complication rates, and renal function parameters being slightly worse than in expanded criteria donors, but still generally acceptable. The use of old kidneys in old recipients, bearing in mind their usual life expectancy, gives them a properly functioning kidney and improved quality of life
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
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