1,721,067 research outputs found
The effect of prolonged fasting on levels of growth hormone-binding protein and free growth hormone.
No full textOBJECTIVE: There are limited data on growth hormone-binding protein (GHBP) and free GH levels during the physiological challenge of a prolonged fast. Our aim was to explore the relationships between GHBP, free GH, total GH and non-esterified fatty acid (NEFA) levels during overnight and 24-hour fasts in healthy young adults. DESIGN: We measured nocturnal levels of GHBP at three time-points (22:00, 03:00, 08:00), NEFA every 60 min and ultra-filtered free GH and total GH at 15-minute intervals for 10 h (22:00-08:00) during an overnight and a 24-hour fast in 7 female and 4 male normal-weight subjects aged 24.8 years (range: 22.8-26.9) with BMI 22.5 kg/m² (range: 18-27). RESULTS: Spontaneous free and total GH levels were closely related during the overnight and 24-hour fasts (r=0.99, p<0.0001 and r=0.99, p<0.0001 respectively). 24 h of fasting led to an increase in levels of basal free GH (p=0.03), mean free GH (p=0.04), mean total GH (p=0.04) and NEFA (p<0.0001) whilst GHBP levels remained similar (p=0.8). Percentage free (over total) GH was similar during the overnight and prolonged fasts (p=0.3). There were no associations between levels of NEFA and free (r=0.24, p=0.5) or total GH (r=0.20, p=0.6). CONCLUSIONS: A 24-hour fast led to parallel increases in free and total GH levels whilst there was no discernable change in GHBP levels or the fraction of free GH. This suggests that GHBP plays a role in limiting variations of circulating free GH levels. NEFA levels increased during the prolonged fast but they were not correlated with free or total GH levels
Adiponectin and left ventricular structure and function in healthy adults. J Clin Endocrinol Metab. 2008
No full textContext: Adiponectin inhibits protein synthesis in cardiac myocytes, thereby opposing the effect
of cardiac workload and trophic factors (in particular, insulin) on left ventricular (LV) mass and wall
thickness (WT).
Objective:Wetested whether adiponectinandits isoforms are related toLVmass,WT,andfunction
independently of metabolic factors.
Design: This was a cross-sectional study.
Subjects: The study included 77 healthy volunteers (42 men) aged 30–59 yr with normal LV structure
and function.
Main Outcome Measures: Insulin response and insulin sensitivity were assessed by oral glucose
tolerance test and euglycemic hyperinsulinemic clamp. LV mass, WT, stroke work, chamber function,
and myocardial longitudinal function were evaluated by standard Doppler echocardiography
and tissue Doppler imaging. Total and molecular isoforms of adiponectin were measured in
plasma.
Results: By multivariate analysis, independent factors affecting LV mass were sex, body mass index,
stroke work, and current smoking (R2 0.66). Independent correlates of LV WT were age, stroke
work, and plasma adiponectin (standardized r0.28, 0.41, and0.26, P at least0.005, R20.48).
LV longitudinal late diastolic velocity was independently related to age, body mass index, and
adiponectin (standardized r 0.20, 0.26, 0.33, P at least 0.05, R2 0.30). High-molecularweight
adiponectin (47% of total), but not lower molecular-weight isoforms, insulin sensitivity, or
other metabolic factors, was inversely and independently related to WT (standardized r0.27,
P 0.01) and myocardial longitudinal late diastolic velocity (standardized r 0.28, P 0.05).
Conclusion: In healthy subjects, circulating total and high-molecular-weight adiponectin are related
to LV WT and diastolic function, independently of age and metabolic factor
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
Adiponectin and left ventricular structure and function in healthy adults
No full textContext: Adiponectin inhibits protein synthesis in cardiac myocytes, thereby opposing the effect of cardiac workload and trophic factors ( in particular, insulin) on left ventricular (LV) mass and wall thickness (WT). Objective: We tested whether adiponectin and its isoforms are related to LVmass, WT, and function independently of metabolic factors. Design: This was a cross-sectional study. Subjects: The study included 77 healthy volunteers ( 42 men) aged 30-59 yr with normal LV structure and function. Main Outcome Measures: Insulin response and insulin sensitivity were assessed by oral glucose tolerance test and euglycemic hyperinsulinemic clamp. LV mass, WT, stroke work, chamber function, and myocardial longitudinal function were evaluated by standard Doppler echocardiography and tissue Doppler imaging. Total and molecular isoforms of adiponectin were measured in plasma. Results: By multivariate analysis, independent factors affecting LV mass were sex, body mass index, stroke work, and current smoking (R-2 = 0.66). Independent correlates of LV WT were age, stroke work, and plasma adiponectin (standardized r = 0.28, 0.41, and - 0.26, P at least < 0.005, R-2 = 0.48). LV longitudinal late diastolic velocity was independently related to age, body mass index, and adiponectin ( standardized r = 0.20, 0.26, - 0.33, P at least < 0.05,R-2 = 0.30). High-molecular-weight adiponectin ( 47% of total), but not lower molecular-weight isoforms, insulin sensitivity, or other metabolic factors, was inversely and independently related to WT ( standardized r = - 0.27, P < 0.01) and myocardial longitudinal late diastolic velocity ( standardized r = - 0.28, P < 0.05). Conclusion: In healthy subjects, circulating total and high-molecular-weight adiponectin are related to LV WT and diastolic function, independently of age and metabolic factors
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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