1,723,751 research outputs found
Effects of BDF 9198 on left ventricular contractility in advanced spontaneously hypertensive rats with heart failure
In the first part of this study, we characterized 24-month-old Wistar Kyoto (WKY) rats and spontaneously hypertensive rats (SHRs), their heart weights, and the responses of the isolated left ventricles to electrical stimulation. In the main part of the study, we tested whether the positive inotropic effects of BDF 9198, which prevents the closure of the cardiac sodium channel, were present in senescence and heart failure. Thus, we studied the effects of BDF 9198 on the left ventricle strips of 24-month-old WKY rats (senescence) and SHRs using contractility methods. In comparison with WKY rats, the left ventricles of 24-month-old SHRs were hypertrophied and had prolonged times to peak contraction. BDF 9198 (10(-8) to 10(-6) m) was a positive inotrope on the left ventricles of WKY rats, with a maximum augmenting effect of 122% with BDF 9198 at 10(-7) m. The magnitude of the augmenting effects of BDF 9198 were reduced in SHR heart failure, with a maximum augmenting effect of 26% at 10(-7) m. BDF 9198 at 10(-6) m attenuated the responses of the SHR left ventricle to electrical stimulation. In conclusion, the potential of drugs that prevent closure of the sodium channel as positive inotropes in the treatment of heart failure should be further considered
Linked collectors and determiners for: Specimens from the National Herbarium of Trinidad and Tobago.
Natural history specimen data linked to collectors and determiners held within, "Specimens from the National Herbarium of Trinidad and Tobago". Claims or attributions were made on Bionomia by volunteer Scribes, <a href="http://bionomia.net/dataset/3c9aeaf9-3a57-4b26-9198-ffa15a8f95a3">https://bionomia.net/dataset/3c9aeaf9-3a57-4b26-9198-ffa15a8f95a3</a> using specimen data from the dataset aggregated by the Global Biodiversity Information Facility, <a href="https://gbif.org/dataset/3c9aeaf9-3a57-4b26-9198-ffa15a8f95a3">https://gbif.org/dataset/3c9aeaf9-3a57-4b26-9198-ffa15a8f95a3</a>. Formatted as a Frictionless Data package
Effects of BDF 9198 on action potentials and ionic currents from guinea-pig isolated ventricular myocytes.
BDF 9198 (a congener of DPI 201 - 106 and BDF 9148) was found to be a positive inotrope on guinea-pig isolated ventricular muscle strips. The effects of BDF 9198 on action potentials and ionic currents from guinea-pig isolated ventricular myocytes were studied using the whole cell patch clamp method. In normal external solution, at 37 degrees C, action potential duration at 50% repolarization (APD(50)) was 167.4+/-8.36 ms (n=37). BDF 9198 produced a concentration-dependent increase in APD(50) (no significant increase at 1x10(-10) M; and APD(50) values of 273.03+/-35.8 ms at 1x10(-9) M; n=6, P<0.01 and 694.7+/-86.3 ms at 1x10(-7) M; P<0.001, n=7). At higher concentrations in the range tested, BDF 9198 also induced early and delayed and after-depolarizations. Qualitative measurements of I(Na) with physiological [Na](o) showed prolongation of the current by BDF 9198, and the appearance of transient oscillatory inward currents at high concentrations. Quantitative recording conditions for I(Na) were established using low external [Na] and by making measurements at room temperature. The current - voltage relation, activation parameters and time-course of I(Na) were similar before and after a partial blocking dose of Tetrodotoxin (TTX, 1 microM), despite a 2 fold difference in current amplitude. This suggests that voltage-clamp during flow of I(Na) was adequately maintained under our conditions. Selective measurements of I(Na) at room temperature showed that BDF 9198 induced a concentration-dependent, sustained component of I(Na) (I(Late)) and caused a slight left-ward shift in the current - voltage relation for peak current. The drug-induced I(Late) showed a similar voltage dependence to peak current in the presence of BDF 9198. Both peak current and I(Late) were abolished by 30 microM TTX and were sensitive to external [Na]. Inactivation of control I(Na) during a 200 ms test pulse to -30 mV followed a bi-exponential time-course. In addition to inducing a sustained current component, BDF 9198 left the magnitude of the fast inactivation time-constant unchanged, but increased the magnitude of the slow inactivation time-constant. Additional experiments with a longer pulse (1 s) raised the possibility that in the presence of BDF 9198, I(Na) inactivation may be comprised of more than two phases. No significant effects of 1x10(-6) M BDF 9198 were observed on the L-type calcium current, or delayed and inward rectifying potassium currents measured at 37 degrees C. It is concluded that the prolongation of APD(50) by BDF 9198 resulted from selective modulation of I(Na). Reduced current inactivation induced a persistent I(Na), increasing the net depolarizing current during the action potential. This action of the drug indicates a potential for 'QT prolongation' of the ECG. The observation of after-depolarizations suggests a potential for proarrhythmia at some drug concentrations
Entre humilité et autorité : Jean Miélot, scribe-traducteur au travail (BnF fr. 9198)
La chronique du musée de Clunyhttps://museecluny.hypotheses.org/11098À partir d'une étude comparée des folios 2 et 19 du ms. BnF fr. 9198, il s'agit d'examiner les postures d'auteurs et leur matériel d'écriture
Entre humilité et autorité : Jean Miélot, scribe-traducteur au travail (BnF fr. 9198)
Par Florence Bouchet, professeure à l'Université Toulouse – Jean Jaurès, PLH, EA 4601 Vie et Miracles de Notre Dame, Paris, BnF, fr. 9198, fol. 19: Jean Miélot dans son atelier. Vie et Miracles de Notre Dame, Paris, BnF, fr. 9198, fol. 2 : saint Jérôme écrivant. ***** Jean Miélot a travaillé à la cour de Bourgogne à partir de 1448, au service de Philippe le Bon jusqu’à la mort de celui-ci en 1467, puis de Charles le Téméraire et de Louis de Luxembourg. Il était à la fois traducteur, copiste ..
Going Beyond Counting First Authors in Author Co-citation Analysis
The 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
“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
We 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
We 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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