1,721,051 research outputs found
Exhaled nitric oxide and exercise performance in heart failure
No full textIn heart failure abnormalities of pulmonary function are frequently observed particularly during exercise, which is characterized by hyperpnea, low tidal volume, early expiratory flow limitation and reduced lung compliance. Exhaled nitric oxide (NO) is increased in asthma. We evaluated whether a correlation between exhaled NO and lung mechanics exists during exercise in heart failure
Exercise-induced changes in exhaled nitric oxide in heart failure
No full textIn heart failure abnormalities of pulmonary function are frequently observed as shown by hyperpnea, reduced lung compliance, reduced alveolar-capillary gas diffusion, positive methacholine challenge and, during exercise, early expiratory flow limitation. Nitric oxide (NO) might be related to all the above abnormalities
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
Cardiopulmonary interaction in heart failure
No full textIn heart failure lung dysfunction is frequent and is greater the greater the heart failure severity. It can be evaluated in terms of lung mechanics and gas diffusion. Indeed heart-lung interaction is related to heart dimensions and lung fluid content; furthermore heart-lung interaction is influenced by the body position. Lung diffusion is also altered in patients with chronic heart failure, and a low gas diffusion is associated with a reduced performance. During exercise, heart-lung interaction becomes more evident. Heart failure patients show an abnormal hyperventilation due to a progressively increased respiratory rate, and a lower tidal volume; hyperventilation is due to different causes including enhanced responses from chemo- and metabolo-receptors, increased CO(2) production and increased dead space ventilation. Several drugs affect the ventilatory pattern in heart failure patients: ACE-inhibitors and anti-aldosteronic drugs improve lung diffusion and ventilatory efficiency during exercise; beta-blockers reduce exercise-induced hyperventilation. Furthermore, ultrafiltration improves lung mechanics, both at rest and during exercise, through body fluid content reduction
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
Subclinical pulmonary edema in endurance athletes
Full text linkStrenuous exercise may cause progressive and proportional haemodynamic overload damage to the alveolar membrane, even in athletes. Despite the high incidence of arterial desaturation reported in endurance athletes has been attributed, into other factors, also to the damage of the alveolar-capillary membrane this evidence is equivocal. Some studies demonstrated flood of the interstitial space and consequent increase in pulmonary water content, but most of them were able to show this through indirect signs of interstitial oedema. The present review illustrates the literature's data in favour or against pulmonary interstitial edema due to intense exercise in athletes
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
Impeded alveolar-capillary gas transfer with saline infusion in heart failure
No full textThe microvascular pulmonary endothelium barrier is critical in preventing interstitial fluid overflow and deterioration in gas diffusion. The role of endothelium in transporting small solutes in pathological conditions, such as congestive heart failure (CHF), has not been studied. Monitoring of pulmonary gas transfer during saline infusion in CHF was used to probe this issue. Carbon monoxide diffusion (DL(CO)), its membrane diffusion (D(M)) and capillary blood volume (V(C)) subcomponents, and mean right atrial (rap) and mean pulmonary wedge (wpp) pressures after saline or 5% D-glucose solution infusions were compared with baseline in 26 moderate CHF patients. Saline was also tested in 13 healthy controls. In patients, 750 mL of saline lowered DL(CO) (-8%, P < 0.01 versus baseline), D(M) (-10%, P < 0.01 versus baseline), aldosterone (-29%, P < 0.01 versus baseline), renin (- 52%, P < 0.01 versus baseline), and hematocrit (-6%, P < 0.05 versus baseline) and increased V(C) (20%, P < 0.01 versus baseline), without changing rap and wpp. Saline at 150 mL produced qualitatively similar results regarding DL(CO) (-5%, P < 0.01 versus baseline), D(M) (-7%, P < 0.01 versus baseline), V(C) (9%, P < 0.01 versus baseline), rap, wpp, aldosterone (-9%, P < 0.05 versus baseline), and renin (-14%, P < 0.05 versus baseline). Glucose solution (750 mL), on the contrary, increased DL(CO) (5%, P < 0.01 versus 750 mL of saline) and D(M) (11%, P < 0.01 versus 750 mL of saline) and decreased V(C) (-9, P < 0.01 versus 750 mL of saline); aldosterone (-40%), renin (- 41%), hematocrit (-3%), rap, and wpp behaved as they did after saline infusion. In controls, responses to both saline amounts were similar to responses in CHF patients regarding aldosterone, renin, hematocrit, rap, and wpp, whereas DL(CO), D(M), and V(C) values tended to rise. Hindrance to gas transfer (reduced DL(CO) and D(M)) with salt infusion in CHF, despite an increase in V(C) and no variations in pulmonary hydrostatic forces, indicates an upregulation in sodium transport from blood to interstitium with interstitial edema. Redistribution of blood from the lungs, facilitating interstitial fluid reabsorption, or sodium uptake from the alveolar lumen by the sodium-glucose cotransport system might underlie the improved alveolar- capillary conductance with glucose
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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