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Validazione istologica della tecnica di caratterizzazione tissutale ultrasonica delle lesioni aterosclerotiche.
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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
Cardiovascular effects of isovolumetric distension of the proximal stomach in healthy humane
No full textIntravascular Doppler technique for monitoring renal venous blood flow in man
No full textBackground: To measure renal blood flow (RBF) from the renal veins in men using the intravascular Doppler technique (IVD). Methods: In nine hypertensive male patients (age 46-64 years) undergoing diagnostic renal artery angiography and renal vein catheterization to determine plasma renin activity (PRA), a 3F Doppler catheter was positioned in the renal veins using a 7F guide catheter with a "basket" shaped tip. The radiopaque sectors of the catheter, leaning against the vessel wall, serve to measure the internal diameter of renal veins, and therefore to calculate RBF, by multiplying renal vein cross-sectional area by mean blood flow velocity. The resulting RBF from the left and right renal veins were compared with those obtained by the local thermodilution method (TD). Results. We found good agreement (Bland and Altman's method) between the RBF measurements made with IVD (ranging from 46 mL/min to 1220 mL/min) and with the TD technique (45-1030 mL/min) (mean bias, 1320 mL/min, 95% CI -54.77 to 28.77 mL/min). In stenotic kidneys a significant correlation was found between the renal vein PRA and RBF calculated with both methods (IVD: r = 0.96, p = 0.002; TD: r = 0.90, p = 0.01). Conclusions. The IVD technique applied to the venous side of the renal circulation provides a simple and reliable method for separate measurement of RBF in kidneys with and without renal artery stenosis
Cardiovascular effects of gastric intubation and distension in healthy humans
No full textFew data exist on the effect of upper gut stimuli on the cardiovascular system. Aim of our study was to evaluate the cardiovascular effects of gastric intubation and distension. Eleven healthy subjects (eight men, aged 21-30 years) were studied and a non-invasive beat-to-beat cardiovascular monitoring system was used. After 15-min basal recording, a bag catheter was positioned in the proximal stomach and connected to a barostat. Recordings were first performed for 15 min with the bag deflated, then during inflation of air using a 100 mL per 2 min stepwise protocol until epigastric discomfort was reported, and finally for 15 min with the bag inflated at 75% of discomfort volume separed from the preceding period by 10 min with the bag deflated. Presence of the deflated bag catheter significantly increased mean arterial pressure. Stepwise distension progressively increased heart rate and cardiac index, while mean arterial pressure was affected only at discomfort volume. Peripheral resistances and systemic plasma catecholamines were unaffected. During prolonged distension, the effect on heart rate and cardiac index was transient. In conclusion, both gastric intubation and distension alter cardiovascular parameters, but the effect of distension undergoes rapid adaptation. Experimentally induced gastric distension is a valuable stimulus to study viscero-cardiovascular reflexes and their mechanisms using beat-to-beat measurements
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
Angiotensin II reduces the rate of rise of coronary sinus blood flow during isometric exercise
No full textClassificazione istologica delle lesioni aterosclerotiche carotidee mediante caratterizzazione tessutale ultrasonica
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