1,720,959 research outputs found
Caratterizzazione della sintesi della molecola segnale ossido nitrico in Paramecium primaurelia
No full textCaratterizzazione della sintesi della molecola segnale ossido nitrico in Paramecium primaurelia.
No full textDictyostelium discoideum: un modello cellulare per lo studio degli effetti di campi elettromagnetici di bassa intensità e frequenza.
No full textEffetti dell'esposizione a campi elettromagnetici di bassa intensità e frequenza sul protista sarcodino Dictyostelium discoideum.
No full textNitric oxide production is inhibited by xenobiotic compounds in the protozoan Paramecium primaurelia.
No full textThe notable increase in agricultural and industrial activities over the last decades has caused a
considerable increase in anthropogenic waste and, consequently, the presence of pollutants in both
water and sediments. For this reason, there is great interest in identifying alternative models and
bioassays complying with the 3Rs strategy (aimed at Reducing, Refining and Replacing tests on
vertebrate organisms in toxicological studies). Protozoa seem to be well suited to this strategy and it is
widely accepted that assays with protozoa are relevant to the study of environmental modifications due
to the presence of xenobiotic compounds.
Recently, we detected the presence of nitric oxide synthase (NOS)-related NADPH-diaphorase activity
and neuronal NOS-relatedmolecules, immunologically recognized by the anti-rat brain NOS antibody, in
a single-cell freshwater eukaryote, Paramecium primaurelia. In this work we have looked for the basal NO
production in living cells of P. primaurelia using the specific fluorescent probe 4,5-diaminofluorescein
diacetate (DAF-2 DA) and measuring the intracellular NO levels with image analysis. The NO production
was sensitive to compounds modulating NOS activity such as: S-methyl-tiocitrulline, an NOS activity
inhibitor, L-NAME, an analogue of arginine that inhibits NO production, arginine, an NOS substrate, or
sodium nitroprusside, an NO donor. The NO production in P. primaurelia was also shown to be sensitive
to mM concentrations of heavy metals (HgCl2 and CdCl2), or mM concentrations of pesticides (diazinon
and AFD 25), thus representing a potential biomarker for environmental biomonitoring. The possible
involvement of cellular Ca2+ concentration, assayed by the fluorescent probe chlortetracycline
hydrochloride, in NO production was examined after xenobiotic exposure
Effetti dell'esposizione in vivo e in vitro a composti xenobiotici, sulle attività cellulari di Euplotes crassus.
No full textNitric oxide production inhibited by xenobiotic compounds in the protozoan Paramecium primaurelia
No full textThe notable increase in agricultural and industrial activities over the last decades has caused a considerable increase in anthropogenic waste and, consequently, the presence of pollutants in both water and sediments. For this reason, there is great interest in identifying alternative models and bioassays complying with the 3Rs strategy (aimed at Reducing, Refining and Replacing tests on vertebrate organisms in toxicological studies). Protozoa seem to be well suited to this strategy and it is widely accepted that assays with protozoa are relevant to the study of environmental modifications due to the presence of xenobiotic compounds. Recently, we detected the presence of nitric oxide synthase (NOS)-related NADPH-diaphorase activity and neuronal NOS-related molecules, immunologically recognized by the anti-rat brain NOS antibody, in a single-cell freshwater eukaryote, Paramecium primaurelia. In this work we have looked for the basal NO production in living cells of P. primaurelia using the specific fluorescent probe 4,5-diaminofluorescein diacetate (DAF-2 DA) and measuring the intracellular NO levels with image analysis. The NO production was sensitive to compounds modulating NOS activity such as: S-methyl-tiocitrulline, an NOS activity inhibitor, l-NAME, an analogue of arginine that inhibits NO production, arginine, an NOS substrate, or sodium nitroprusside, an NO donor. The NO production in P. primaurelia was also shown to be sensitive to μM concentrations of heavy metals (HgCl2 and CdCl2), or μM concentrations of pesticides (diazinon and AFD 25), thus representing a potential biomarker for environmental biomonitoring. The possible involvement of cellular Ca2+ concentration, assayed by the fluorescent probe chlortetracycline hydrochloride, in NO production was examined after xenobiotic exposure. © 2009 Elsevier Ltd. All rights reserved
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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