1,720,969 research outputs found
The action of polypeptides, amines and prostaglandins on isolated smooth muscle preparations of seminal vesicles and deferent ducts
The spasmogenic effect of 11 biogenic polypeptides, 2 prostaglandins and 3 amines was assayed, in parallel, on the isolated seminal vesicles and deferent ducts of the rat, guinea pig and hamster. The smooth muscle preparations were contracted by most of the examined compounds, but none of the preparations appeared to be particularly sensitive, and not infrequently bioassay was made difficult by tachyphylaxis. Thus, the smooth muscle preparations of the male genital tract, although containing receptors for biogenic polypeptides and amines, cannot be considered as test objects of first choice in the qualitative and quantitative bioassay of these compounds
The use of preparations of urinary bladder smooth muscle for bioassay of and discrimination between polypeptides.
Eleven polypeptides, two prostaglandins and three amines were assayed, in parallel, by measurement of their spasmogenic effect on the isolated urinary bladder of eight animal species, the in situ bladder of three species and the isolated ureter of three species. Several of the smooth muscle preparations examined proved to be sensitive and suitable test-objects for the quantitative bioassay of different peptides. At the same time they appeared to be useful for discriminating not only between peptides belonging to different groups, but also between members of the same peptide family. It is tentatively suggested that biogenic peptides may interfere in the physiological control of motility and tone of the urinary tract smooth muscle
Produzione di preparati a base di piante medicinali o salutari: normativa europea e proposte di regolamentazione
OCULAR PHARMACOKINETICS OF DAPIPRAZOLE
Dapiprazole is a drug having specific alpha1 adrenergic blocking properties. Following topical instillation on the eye, it crosses the corneal epithelium reaching high concentrations in the ocular tissue and producing a prompt miotic and hypotensive effect. The high concentration ratio between ciliary bodies and iris versus aqueous humor suggests a peculiar affinity for these structures containing adrenoceptors of the alpha type. The very low concentrations in the plasma, as compared to those after systemic administration, and in the fellow eye indicate that the systemic absorption is negligible. © 1986
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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