1,720,988 research outputs found
[Positive indicators in scintigraphic diagnosis in pneumology (studies with Na75Se, 197HgCl2, 67Ga in 292 subjects].
No full textPermeabilità bronchiale transepiteliale. Basi anatomo-funzionali e implicazioni cliniche
No full textErratum: Nitric oxide attenuates platelet-activating factor induced nasal airway plasma extravasation in healthy subjects (European Journal of Clinical Investigation (2002) 32 (858-861))
No full textNitric oxide attenuates platelet-activating factor-induced nasal airway plasma extravasation in healthy subjects
No full textBackground: Paranasal sinuses and the nose are important sources of nitric oxide (NO) in humans but the relevance of NO production to the control of nasal airway plasma exudation and its response to inflammatory mediators such as platelet-activating factor (PAF) in healthy subjects is not well known. Design: In this study we aimed to evaluate the effect of the nitric oxide synthase (NOS) inhibitor NG L-arginine methyl ester (L-NAME) on nasal airway plasma extravasation at baseline and after an acute challenge with PAF that induces most symptoms of rhinitis. Eleven healthy subjects were enrolled in the study. Plasma extravasation in the nasal airway was assessed by measuring the albumin content of nasal lavage. Results: PAF challenge caused a significant increase in concentrations of albumin in the nasal lavage fluid (from 0.59 ± 0.13 mg dL-1 to 2.46 ± 0.45 mg dL-1) after placebo. Pretreatment with L-NAME significantly prevented the increase of albumin in the nasal lavage fluid induced by PAF as compared to placebo (from 0.53 ± 0.11 mg dL-1 to 1.70 ± 0.28 mg dL-1; P < 0.005). Conclusion: Topical administration of a NO inhibitor is able to attenuate the nasal airway plasma extravasation induced by PAF, suggesting that NO release in vivo is involved in the nasal response to PAF
Effect of nitric oxide inhibition on nasal airway resistance after nasal allergen challenge in allergic rhinitis
No full textBackground - Nitric oxide has been detected by chemiluminescence in the lumen of nasal airway, which is increased in nasal breathing in patients with seasonal rhinitis during a chronic exposure. The purpose of this study was to determinate the effect of a NO-synthase inhibitor NGL-arginine methyl ester (L-NAME) on nasal airway resistance (NAR) in patients with seasonal allergic rhinitis after an acute challenge to the allergen. Methods - Nitric oxide levels in the nose were measured by the chemiluminescence method in nine non-atopic volunteers and in seven patients with seasonal rhinitis at rest and after an acute challenge with the allergen. NAR were measured by active anterior rhinomanometry. Results - Basal nasal NO concentration in allergic rhinitis was 496.5 ± 151.4 parts per billion (ppb). (n = 7) and it was not significantly different from levels found in the control group: 458.4 ± 105.9 ppb (n = 9). The topical administration of L-NAME in allergic rhinitis reduced the NO concentration (338.6 ± 99.3 ppb, P < 0.001; n = 7). In the rhinitic patients the challenge with the allergen did not modify the nasal NO levels (504.5 ± 138.5 ppb). The application of the allergen after the pretreatment with placebo caused a significant increase in NAR (from 0.32 ± 0.11 Pa s cm-3 to 1.01 ± 0.12 Pa s cm-3;, P < 0.001; n = 7). Pre-treatment with L-NAME did not prevent the increase in NAR induced by allergen challenge (from 0.36 ± 0.15 Pa s cm-3 to 1.06 ± 0-26 Pa s cm-3). Conclusions - The results indicate that nasal administration of a NOS inhibitor L-NAME, at doses capable of decreasing nasal NO levels, has no effect on NAR and it does not prevent the NAR increase induced by an acute challenge with allergen in subjects with seasonal rhinitis
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
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