1,720,962 research outputs found
Glycemic index, glycemic load and risk of gastric cancer
No full textBackground: Dietary carbohydrates have been directly associated with gastric cancer risk and have been considered general indicators of a poor diet. However, elevated levels of glucose and insulin elicited by consumption of high amounts of refined carbohydrates may stimulate mitogenic and cancer-promoting insulin-like growth factors (IGF). Glycemic index (GI) and glycemic load (GL), which represent indirect measures of dietary insulin demand, were analysed to understand further the association between carbohydrates and gastric cancer. Patients and methods: Data were derived from a hospital-based case-control study on gastric cancer, conducted in Italy between 1985 and 1997, including 769 cases with incident, histologically confirmed gastric cancer and 2081 controls admitted to the same hospital network as cases for acute, non-neoplastic diseases. All subjects were interviewed using a reproducible food frequency questionnaire. Results: The multivariate odds ratios (OR) for subsequent quartiles of dietary GL were 1.44 [95% confidence interval (CI) 1.11-1.87], 1.62 (95% CI 1.24-2.12) and 1.94 (95% CI 1.47-2.55). No consistent pattern of risk was seen with GI. The associations were consistent in different strata of age, education and body mass index, and were stronger in women. Conclusions: This study supports the hypothesis of a direct association between GL and gastric cancer risk, thus providing an innovative interpretation, linked to excess circulating insulin and related IGFs, for the association between carbohydrates and risk of gastric cancer
Alcohol consumption and acute myocardial infarction: A benefit of alcohol consumed with meals?
No full textBackground: The apparent favorable effect of alcohol on the risk of acute myocardial infarction (MI) may be related to its hypoinsulinemic effect when consumed with meals. We studied how the timing of alcohol consumption in relation to meals might affect the risk of MI in a population with relatively high regular alcohol consumption. Methods: We conducted a case-control study between 1995 and 1999 in Milan, Italy. Cases were 507 subjects with a first episode of nonfatal acute MI, and controls were 478 patients admitted to hospitals for other acute diseases. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated by multiple logistic regression models. Results: Compared with nondrinkers, an inverse trend in risk was observed when alcohol was consumed during meals only (for greater than or equal to3 drinks per day: OR=0.50; 95% CI=0.30-0.82). In contrast, no consistent trend in risk was found for subjects drinking outside of meals (for greater than or equal to3 drinks per day: 0.98; 0.49-1.96). The pattern of risk was similar when we considered people who drank only wine. Conclusions: Alcohol drinking during meals was inversely related with risk of acute MI, whereas alcohol drinking outside meals only was unrelated to risk
Dietary glycemic index and glycemic load, and breast cancer risk: A case-control study
No full textBackground: Certain types of carbohydrates increase glucose and insulin levels to a greater extent than others. In turn, insulin may raise levels of insulin-like growth factors, which may influence breast cancer risk. We analyzed the effect of type and amount of carbohydrates on breast cancer risk, using the glycemic index and the glycemic load measures in a large case-control study conducted in Italy. Patients and methods: Cases were 2569 women with incident, histologically-confirmed breast cancer interviewed between 1991 and 1994. Controls were 2588 women admitted to the same hospital network for a variety of acute, non-neoplastic conditions. Average daily glycemic index and glycemic load were calculated from a validated 78-item food frequency questionnaire. Results: Direct associations with breast cancer risk emerged for glycemic index (odds ratio, OR for highest vs. lowest quintile = 1.4; P for trend <0.01) and glycemic load (OR = 1.3; P < 0.01). High glycemic index foods, such as white bread, increased the risk of breast cancer (OR = 1.3) while the intake of pasta, a medium glycemic index food, seemed to have no influence (OR = 1.0). Findings were consistent across different strata of menopausal status, alcohol intake, and physical activity level. Conclusions: This study supports the hypothesis of moderate, direct associations between glycemic index or glycemic load and breast cancer risk and, consequently, a possible role of hyperinsulinemia/insulin resistance in breast cancer development. RI Jenkins, David/A-1992-2009; Parpinel, Maria/B-1605-201
Glycemic index and load and risk of upper aero-digestive tract neoplasms (Italy)
No full textBackground: The ability of dietary carbohydrates to affect blood glucose and insulin levels by dietary carbohydrates is best measured by the glycemic index (GI) and glycemic load (GL) which have been directly associated with risk of several chronic conditions, including cancer. Patients and methods: Three case - control studies were conducted between 1992 and 2000 in Italy. The first one included 598 hospital patients with incident, histologically confirmed oral and pharyngeal cancer and 1491 controls admitted to the same hospital networks for acute, non-neoplastic diseases; the second study included 304 subjects with squamous cell oesophageal cancer and 743 controls; the third one included 460 cases with laryngeal cancer and 1088 controls. All subjects were interviewed using a validated food frequency questionnaire. Results: The odds ratios ( OR) of upper aero-digestive tract neoplasms for the highest versus the lowest quintile of dietary GI and GL were 1.5 (95% confidence interval [CI]: 1.1 - 2.0) and 1.8 ( 95% CI: 1.1 - 2.9), respectively. The associations were in the same direction for various cancer sites. The ORs were apparently stronger in women, in those with high body mass index and reporting low alcohol consumption. Conclusions: This study supports the hypothesis that high dietary GI and GL are associated with cancers of the upper aero-digestive tract. RI Jenkins, David/A-1992-200
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
Glycemic index, glycemic load and risk of prostate cancer
No full textDietary carbohydrates have different glycemic and insulinemic potentials depending on type (glycemic index, GI) and amount (glycemic load, GL) of carbohydrate consumed or both. Insulin in turn has been implicated as a risk factor for several cancers, including that of the prostate. We assessed the relationship of GI and GL with prostate cancer risk in a multicenter case-control study. Cases and controls were recruited between 1991 and 2002 in the network of major teaching and general hospitals in 4 Italian areas. Cases were 1,204 men (age range 46-74 years) admitted for incident, histologically confirmed prostate cancer. Controls were 1,352 men (age range 46-74 years) admitted for acute, nonmalignant conditions unrelated to long-term modifications of diet. ORs of prostate cancer and the corresponding 95% Cls were derived using unconditional multiple logistic regression, including terms for age, study center, education, family history of prostate cancer, smoking, body mass index, physical activity, alcohol consumption, intake of energy, fiber and lycopenes. Compared to the lowest quintile of GI, the ORs were 1.23, 1.24, 1.47 and 1.57 for subsequent levels of GI. The corresponding values for GL were 0.91, 1.00, 1.20 and 1.41. No heterogeneity was found among strata of selected covariates. We found direct relations between dietary GI and GL and prostate cancer risk. Correcting for potential confounding factors did not substantially modify these associations. (C) 2004 Wiley-Liss, Inc. RI Jenkins, David/A-1992-200
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
- …
