1,720,957 research outputs found
Patologia parodontale e aterosclerosi : Identificazione dei batteri parodontali nella placca carotidea
No full textFormazione di Biofilm da Enterococcus faecalis in diversi preparati endodontici: valutazione mediante metodi molecolari
No full textObjective: The adhesion abilities of Enterococcus Faecalis in the root
canals represent the essential condition during endodontic pathologies,
because of the biofilm nature of these diseases. In this contest,
the present study investigated the adhesion of E Faecalis in 3 different
endodontic medicaments by a biofilm model in vitro of E Faecalis: (i)
CPD, (ii) Endoidrox, (iii) PulpCanalSealer.
Methods: The adhesion index of the samples was evaluated for 10 days
after shaking the cultures at 37°C, by using quantitative real-time PCR
for the 16S rRNA gene.
Results: The highest concentration of adherent bacteria was found after
9 days in the PulpCanalSealer (maximum level of the adhesion index =
2.9x104), followed by CPD (2.7x103), while Endoidrox showed the lowest
adhesion index (5x102). None of these intracanalar preparations showed
antibacterial activity against E Faecalis.
Conclusions: The present study confirmed the E Faecalis ability to persist
in any endodontic medicament. In addition our work evaluated
the adhesion index of E Faecalis biofilm in three different medicament
preparations. Our results may contribute to the explanation of how
the microorganism can survive inside filled chambers
A rapid sample method for HLA haplotype typization. A preliminary study on celiac patients
No full textAbstract
AIM:
The aim of the present work was to determine the human leukocyte (HLA) haplotype in 64 Sardinian patients affected with celiac disease, using a rapid and easy to apply sampling method that permits samples from blood drawing to be stored more easily. Numerous studies have demonstrated how the HLA system plays a very important role in immune system regulation, determining a link between this gene and a high number of pathologies including celiac disease. In fact a genetic susceptibility exists in celiac sprue, linked to HLA-DQB1*0201 and -DQB1*0302 genes which represent sierologic groups -DQ2 and -DQ8 whose early identification could be fundamental in obtaining a diagnosis of celiac disease.
METHODS:
To realize this study a collecting method of samples was developed through the brushing of oral mucosa, which is extremely less traumatic than the classic sampling method using blood drawing, and which also allows a long conservation period before sample analysis. Samples were later analyzed with Van Embden's DNA extraction method to extract the patient's DNA, on which we executed the Polymerase Chain Reaction (PCR). To obtain the HLA haplotype from each patient we used 8 specific primers that amplified the HLA-DQB1 allele in low-resolution.
RESULTS:
Out of the 64 patients we found 26 HLA-DQB1*02 homozygotes, 28 HLA-DQB1*02 heterozygotes and 10 negative samples for the HLA-DQB1*02 allele, thus confirming what had emerged from previous blood draws.
CONCLUSION:
These results show how the method we developed using oral brushing is a sure method to obtain samples for determining the HLA haplotype in extra-hospital areas. This could allow the use of this method to obtain early diagnosis for chronic pathologies linked to the HLA groups and for recognizing this genotype in extensive population studie
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
- …
