1,721,021 research outputs found
Molecular modeling, theoretical calculations and property evaluation of three muscarinic agonists, X-ray structures of LU 25-109 and WAL 2014
No full textLU 25-109 (II) and WAL 2014 (talsaclidine, III) are two M1 muscarinic agonists chemically related to the natural substance arecoline (I). All these compounds have beneficial effects on memory and cognition in animals and humans, and they have been proposed in the treatment of Alzheimer's disease, but only III will likely find a place in therapy. In this work we have investigated the solid state structures of II and III and the X-ray structures of the two molecules and of the parent compound I have been used to input a series of computational chemistry efforts. In particular, the X-ray geometries have been manipulated to model 20 molecular structures (1-20) which have been submitted to ab initio, semiempirical quantum mechanics and molecular mechanics calculations. The conformational space accessible to the 20 structures has been assessed by means of potential energy maps. The reactivities of 1-20 have been estimated by examining at the graphics terminal the composition and the extension of the frontier orbitals (HOMOs and LUMOs) and of the molecular electrostatic potential. The information obtained has been interpreted to explain the different degrees of activity shown by I-III. Our data indicate that III has better in vivo activity for its intermediate size, less polar surface, conformational rigidity and orientation of reactive domains. (C) 2000 Elsevier Science B.V. All rights reserved
INCREASED URINARY LEVEL OF NEUTROPHIL GELATINASE-ASSOCIATED LIPOCALIN (NGAL) IN PATIENTS WITH CIRRHOSIS AND TYPE 1 HRS
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TERLIPRESSIN AND ALBUMIN VS MIDODRINE PLUS OCTREOTIDE AND ALBUMIN IN THE TREATMENT OF HRS IN PATIENTS WITH CIRRHOSIS: RESULTS OF A CONTROLLED CLINICAL TRIAL BY AISF
No full textGoing 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
ProSPs: Protein Sites Prediction Based on Sequence Fragments
Full text linkIdentifying interacting sites of proteins is a relevant aspect for drug and vaccine design, and it provides clues for understanding the protein function. Although such a prediction is a problem extensively addressed in the literature, just a few approaches consider the protein sequence only. The use of the protein sequences is an important issue because the three-dimensional structure of proteins could be unknown. Moreover, such a structural determination experimentally is expensive and time-consuming, and it may contain errors due to experimentation. On the other hand, sequence based method suffers when the knowledge of sequence is incomplete.In this work, we present ProSPs, a method for predicting the protein residues considering protein sequence fragments, which are obtained using sliding windows and become the samples for an unbalance binary classification problem. We use the Random Forest classifier for data training. Each amino acid is enriched using a selected subset of physicochemical and biochemical amino acid characteristics from the AAIndex1 database. We test the framework on two classes of proteins, Antibody-Antigen and Antigen-Bound Antibody, extracted from the Protein-Protein Docking Benchmark 5.0. The obtained results evaluated in terms of the area under the ROC curve (AU-ROC) on these classes outperform the sequence-based algorithms in the literature and are comparable with the ones based on three-dimensional structure
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
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