1,720,967 research outputs found
Heredity and colorectal cancer
No full textColorectal cancer is the second leading cause of death from malignancies in Western Countries. In spite of advances in treatment, little change in survival has been accomplished in last decades and this mandates greater importance to prevention and early detection. Although dietary factors have received primary attention familial clustering suggests that susceptibility to KCR is inherited. Hereditary colorectal cancer can arise on Familial Adenomatous Polyposis (HCC) or not on polyposis (HNPCC) and members of these families are at high risk of such neoplasias. Anyway, even in "sporadic" forms of KCR first-degree relatives have a 2 to 3-fold increased risk of the same cancer. The most desirable screening protocol would be a simple procedure involving only a blood test to identify gene defect by molecular biology techniques. Unfortunately, this is not practically possible, for lack of specific genetic alterations, out of FAP, and only the study of family history can enable targeted surveillance and cost-effective management strategies
Update on epidemiology and risk factors of colorectal carcinoma [Attualità in tema di epidemiologia e fattori di rischio del carcinoma colo-rettale]
No full textEtiology of colorectal cancer is not completely clear. Epidemiologic studies, especially those on migrant populations, demonstrate the importance of environmental factors, particularly dietary, in cancerogenesis. Anyway, familial aggregation within a given population shows that genetic factors play an important role. General risk factors are represented by age, sex, physical activity... while some pathologies increased the risk of developing KCR or are frankly precancerous (adenomas, ulcerative colitis, Crohn's disease...)
Diffuse cutaneous metastases as the only sign of extranodal tumor spread in a patient with adenocarcinoma of the colon
Full text linkCutaneous metastases from large bowel cancer are uncommon and are usually associated with organ involvement. Localization of lesions to the skin is mainly attributed to vascular and anatomical relationship, since most of them are seen in the abdominal wall or in a surgical scar. We report a 73-year-old woman in whom metastatic nodules from a poorly differentiated adenocarcinoma of the right colon developed throughout the skin (buttock, trunk, chest wall, arms, and neck) and remained the only sign of extranodal tumor spread until patient's death, seven months later. This unusual behaviour suggests that localization of neoplastic cells to the skin may be a site-specific process, determined by adhesion molecules and/or by growth factors found at that sit
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
Germline mutations of mismatch repair genes (MMR) in patients with HNPCC-LIKE syndrome: preliminary results
No full text
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
- …
