1,721,021 research outputs found
Different mechanism of tachykinin NK2 receptor blockade by SR 48968 and MEN 10,627 in the guinea-pig isolated gallbladder and colon
No full textThe mechanism of action of the tachykinin NK2 receptor antagonists, SR 48968 ((S)-N-methyl-N[4-acetylamino-4-phenyl-piperidino)-2-(3,4- dichlorophenyl)butyl]benzmide) and MEN 10,627 (cyclo[Met-Asp-Trp-Phe-Dap-Leu) cyclo (2β-5β)]), was compared in the guinea-pig isolated gallbladder and circular muscle of proximal colon by using neurokinin A and [βAla8]neurokinin A-(4-10) as agonists. The experiments performed with colon were in the presence of the tachykinin NK1 receptor-selective antagonist, (±)-CP-96345 (([2-(diphenylmethyl)-N-[(2-methoxyphenyl]-methyl]-11-azabicyclo[2,2,2]octan-3-amine]) SR 48968 caused an insurmountable antagonism of tachykinin NK2 receptor-mediated contraction in both preparations; its blockade was essentially irreversible, since it was not reversed by washout (up to 2 h) and was increased by prolonging the incubation from 15 to 120 min. In contrast, MEN 10,627 produced simple competitive antagonism, which was time-independent and fully reversible in both preparations. In both preparations, the simultaneous administration of SR 48968 and MEN 10,627 produced an intermediate antagonism of the responses to the agonists, as compared to the antagonism produced by each antagonist alone. The present results are discussed in the light of the reported interaction of SR 48968 with tachykinin NK2 receptors at a recognition epitope distinct from that of agonist(s
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
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
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
Evidence that tachykinins are the main NANC excitatory neurotransmitters in the guinea-pig common bile duct
No full text1. Application of electrical field stimulation (EFS; trains of 10 Hz, 0.25 ms pulse width, supramaximal voltage for 60 s) to the guinea-pig isolated common bile duct pretreated with atropine (1 μM), produced a slowly-developing contraction ('on' response) followed by a quick phasic 'off' contraction ('off peak' response) and a tonic response ('off late' response), averaging 16 ± 2, 73 ± 3 and 20 ± 4% of the maximal contraction to KCl (80 mM), n = 20 each, respectively. Tetrodotoxin (1 μM; 15 min before) abolished the overall response to EFS (n = 8). 2. Neither in vitro capsaicin pretreatment (10 μM for 15 min), nor guanethidine (3 μM, 60 min before) affected the excitatory response to EFS (n = 5 each), showing that neither primary sensory neurons, nor sympathetic nerves were involved. N(ω)-nitro-L-arginine (L-NOARG, 100 μM, 60 min before) or naloxone (10 μM, 30 min before) significantly enhanced the 'on' response (294 ± 56 and 205 ± 25% increase, respectively; n = 6-8, P < 0.01) to EFS. The combined administration of L-NOARG and naloxone produced additive enhancing effects (655 ± 90% increase of the 'on' component, n = 6, P < 0.05). 3. The tachykinin NK2 receptor-selective antagonist MEN 11420 (1 μM) almost abolished both the 'on' and 'off late' responses (P < 0.01; n = 5 each) to EFS, and reduced the 'off-peak' contraction by 55 ± 8% (n = 5, P < 0.01). The subsequent administration of the tachykinin NK1 receptor-selective antagonist GR 82334 (1 μM) and of the tachykinin NK3 receptor-selective antagonist SR 142801 (30 nM), in the presence of MEN 11420 (1 μM) did not produce any further inhibition of the response to EFS (P > 0.05; n = 5 each). At 3 μM, GR 82334 significantly reduced (by 68 ± 9%, P < 0.05, n = 6) the 'on' response to EFS. 4. The contractile 'off peak' response to EFS observed in the presence of both MEN 11420 and GR 82334 (3 μM each) was abolished (P < 0.01; n = 6) by the administration of the P2 purinoceptor antagonist pyridoxalphosphate-6-azophenyl-2',4'-disulphonic acid (PPADS, 30 μM). PPADS (30 μM) selectively blocked (75 ± 9 and 50 ± 7% inhibition, n = 4 each) the contractile responses produced by 100 and 300 μM ATP. 5. Tachykinin-containing nerve fibres were detected by using immunohistochemical techniques in all parts of the bile duct, being distributed to the muscle layer and lamina propria of mucosa. In the terminal part of the duct (ampulla) some labelled ganglion cells were observed. 6. In conclusion, this study shows that in the guinea-pig terminal biliary tract tachykinins, released from intrinsic neuronal elements, are the main NANC excitatory neurotransmitters, which act by stimulating tachykinin NK2 (and possibly NK1) receptors. ATP is also involved as excitatory neurotransmitter. Nitric oxide and opioids act as inhibitory mediators/modulators in this preparation
Effects of capsaicin, tachykinins, calcitonin gene-related peptide and bradykinin in the pig iris sphincter muscle.
No full textkoamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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