1,721,012 research outputs found
Analisi molecolare di ceppi di parvovirus felino (FPV) e canino (CPV-2).
No full textIl Virus della Panleucopenia Felina (FPV), è un virus a DNA appartenente alla famiglia Parvoviridae, genere Parvovirus, sottogruppo del parvovirus felino, di cui rappresenta il capostipite. Il FPV infetta felidi domestici e selvatici determinando una patologia, la panleucopenia felina, caratterizzata da leucopenia, gastroenterite e sintomi nervosi. Oltre al FPV, anche le nuove varianti antigeniche del parvovirus canino CPV-2a/2b/2c hanno esteso lo spettro d'ospite al gatto, determinando una malattia simile alla panleucopenia. Nonostante le strette correlazioni genomiche ed antigeniche esistenti tra il FPV e il CPV-2, le due specie virali hanno mostrato un differente comportamento evolutivo. Mentre il FPV è rimasto stabile nel tempo, il CPV-2 si è evoluto rapidamente, originando le nuove varianti 2a/2b/2c. Nel presente studio preliminare è stata effettuata un'indagine molecolare allo scopo di caratterizzare i ceppi di parvovirus che
circolano nella popolazione felina.
Sono stati analizzati 16 ceppi di Parvovirus isolati da gatti con sintomatologia riferibile a panleucopenia felina, raccolti tra il 2000 e il 2008. Ai fini della caratterizzazione genomica e antigenica, il gene VP2 è stato amplificato e sequenziato; le sequenze nucleotidiche ed aminoacidiche ottenute sono state sottoposte ad analisi filogenetica ed evolutiva utilizzando diversi softwares. Inoltre, per alcuni ceppi virali si è proceduto al clonaggio e successiva analisi dei cloni.
L'analisi delle sequenze ha evidenziato che 14 ceppi virali erano tipici FPV, mentre 2 ceppi erano rispettivamente CPV-2c e 2a. L'analisi dei cloni dei ceppi di Parvovirus canino, ha permesso di stabilire che nei soggetti infettati da CPV-2, vi era un'elevata complessità genetica con la presenza di più popolazioni virali nello stesso animale, nonché una co-infezione con presenza nello stesso animale di CPV-2 e FPV.
Nei gatti analizzati è stata riscontrata una netta prevalenza del tipico FPV, che conferma la stabilità di questo virus; invece l'elevata complessità genetica rilevata nei ceppi di CPV-2, conferma la tendenza del CPV-2 ad evolversi con un tasso di mutazione
particolarmente elevato, comparabile ad un RNA virus. Inoltre si tratta della prima segnalazione di un'infezione mista da Parvovirus felino e canino nel gatto, che insieme alle caratteristiche di quasispecie dei ceppi evidenziati, fa ipotizzare un importante ruolo epidemiologico svolto dal gatto, ai fini dell'emergenza di nuove varianti di Parvovirus
Antimicrobial susceptibility of vancomycin-susceptible and -resistant enterococci isolated in Italy from raw meat products, farm animals, and human infections.
Get PDFThe susceptibility of vancomycin-resistant (VRE) and vancomycin-susceptible (VSE) enterococci to 10 antimicrobial agents was evaluated. The strains, belonging to different species, were isolated in Italy from raw meat products, farm animals, and human clinical infections in the years 1997–2000. High frequency of resistance to tetracycline and erythromycin was observed in all the groups of strains. On the contrary, chloramphenicol was the only drug that showed a relatively low rate of resistance in all the groups examined. In general, the resistance rates observed for VSE did not differ from those observed for VRE of the same species and origin. Some differences could be noticed among the different enterococcal species, with Enterococcus faecium strains being usually more resistant to beta-lactams, and Enterococcus faecalis strains more resistant to gentamicin. However, the strongest differences were observed when the strains were compared according to their source, the human isolates
being usually more resistant than the isolates of animal origin. No significant difference was observed between isolates of swine and poultry origin. Among VRE E. faecium, multiple resistance was much more frequent among the human strains (90%) than among poultry (48.9%) and swine (26.5%) strains. These results show that in Italy VRE isolates from human clinical infections are usually more resistant than isolates from meat products and farm animals, and possess different antimicrobial resistance profiles
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Get PDFWe 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
Get PDFWe 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
koamabayili/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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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