1,721,006 research outputs found
Can prior vaccinations against certain infections confer protection against developing melanoma?.
No full textAbstract. Currently available, relatively safe vaccines may help tackle this serious and increasing public health problem
Lung cancer risk: effect of dairy farming and the consequence of removing that occupational exposure
No full textAbstract
The aim of this study was to confirm the exposure-dependent reduction in lung cancer risk reported for dairy farmers exposed to endotoxin and to evaluate the consequence of leaving dairy farming and taking employment in industry or services, where exposure to microbial agents is lower. Standardized mortality ratios, with 95% confidence intervals, for 2,561 self-employed dairy farmers were estimated, considering the general population of Veneto, Italy, from 1970 to 1998 as the reference. Sixty-two lung cancer cases, whose information was checked against clinical records, were compared with 333 controls in a cohort-nested case-control study. Odds ratios with 95% confidence intervals were estimated by logistic regression analysis. A downward trend of standardized mortality ratios for lung cancer across tertiles of number of dairy cattle on the farm was significant (p 15 years had elapsed from the end of work to the end of follow-up. In conclusion, increased levels of endotoxin (or other associated environmental factors) might be protective against lung cancer; protection diminishes over time after that exposure is removed
STUDIO EPIDEMIOLOGICO PER INDAGARE L’EFFETTO PROTETTIVO DELLAVACCINAZIONE CONTRO LA FEBBRE GIALLA SULL’INCIDENZA DIMELANOMA
No full textIntroduzione. Uno studio multicentrico europeo caso-controllo ha mostrato una riduzione del rischio di
melanoma associato alla vaccinazione BCG e antivaiolosa nella prima infanzia e/o a malattie infettive
occorse in età adulta. Sulla base di queste osservazioni è stata proposta un’ipotesi d’immuno-sorveglianza
per il melanoma . Questa ipotesi postula l'esistenza di un “marcatore cellulare di rischio di melanoma”,
identificato con la proteina HERV-K-MEL, codificata da Human Endogenous Retro Virus K (HERV-K).
La proteina HERV-K-MEL è un antigene che presenta inaspettate omologie con antigeni di origine
batterica e virale. Una reazione immune diretta contro questi ultimi antigeni porterebbe all'inattivazione
della stessa proteina HERV-K-MEL. L'analogia con l'HERV-K-MEL è particolarmente elevata per una
poliproteina indotta dal virus della febbre gialla. Lo scopo del nostro lavoro è di verificare che nei
soggetti vaccinati contro la febbre gialla l’incidenza del melanoma sia più bassa rispetto a quelli non
vaccinati per febbre gialla.
Metodi. Lo studio è di tipo osservazionale coorte prospettico-storico. La coorte è costituita da soggetti
residenti nella Regione Veneta, vaccinati contro la febbre gialla e/o contro altre malattie presso gli Uffici
Vaccinazioni Internazionali del Veneto per il rilascio dei certificati validi per uso internazionale. E’ stato
eseguito uno studio caso-controllo innestato su coorte. I controlli erano 1074 soggetti affetti da tumore
non melanoma, i casi 60 soggetti con melanoma. Gli esposti erano i vaccinati contro la febbre gialla, i
non esposti i soggetti vaccinati contro altre malattie. Per calcolare gli odds ratio (OR) per melanoma è
stata applicata una regressione logistica, stratificata per centro, aggiustata per sesso età alla vaccinazione
ed età all’insorgenza del tumore.
Risultati. I risultati dimostrano che la categoria degli esposti al vaccino contro la febbre gialla da più di
10 anni hanno un OR significativamente più basso rispetto a coloro che hanno eseguito la vaccinazione da
O a 5 anni (reference category).
Discussione. Sono stati scelti soggetti affetti da altri tumori come controlli per più motivi: innanzitutto
sono soggetti che provengono dalla stessa popolazione che da origine ai casi quella individuata dal
registro tumori; sono affetti da patologie che non sembrano essere associate all’esposizione “febbre
gialla”; la probabilità di selezione di ogni soggetto tra i controlli è proporzionale al tempo per cui esso ha
contribuito al denominatore del tasso che si sarebbe dovuto calcolare qualora uno studio coorte fosse stato
condotto, infatti sono stati selezionati i casi di tumore evidenziati dal Registro Tumori nelle stesse aree
geografiche che hanno individuato i casi di melanoma e che quindi hanno lo stessa dimensione spaziotemporale;
inoltre “l’utilizzo di controlli costituiti da soggetti con una malattia che si manifesta con le
stesse modalità della malattia di interesse (melanoma) potrebbe eliminare una sorgente di ^selection
bias^, se questa malattia con simili manifestazioni non è associata all’esposizione di interesse questi
controlli sono da ritenersi ideali”(Miettinen); infine abbiamo utilizzato come controlli soggetti affetti da
più tumori in quanto usando una varietà di diagnosi si ha il vantaggio della diluizione dell’effetto di bias
che si verifica nell’includere un singola specifica categoria diagnostica che sia eventualmente associata
all’esposizione Le conclusioni del nostro studio evidenziano che la vaccinazione contro la febbre gialla è
protettiva contro il melanoma qualora si venga vaccinati da più di 10 anni prima della manifestazione
clinica della malattia ma non è efficace se somministrato dopo
Inverse association between melanoma and previous vaccinations against tubercolosis and smallpox: results of the FEBIM study
No full text
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
Widespread occurrence of Mycobacterium tuberculosis DNA from 18th-19th century Hungarians
No full textA large number (265) of burials from 1731-1838 were discovered in sealed crypts of the Dominican Church, Vac, Hungary in 1994. Many bodies were naturally mummified, so that both soft tissues and bones were available. Contemporary archives enabled the determination of age at death, and the identification of family groups. In some cases, symptoms before death were described and, occasionally, occupation. Initial radiological examination of a small number of individuals had indicated calcified lung lesions and demonstrable acid-fast bacteria suggestive of tuberculosis infection. Tuberculosis was endemic in 18th-19th century Europe, so human remains should contain detectable Mycobacterium tuberculosis complex (MTB) DNA, enabling comparisons with modern isolates. Therefore, a comprehensive examination of 168 individuals for the presence of MTB DNA was undertaken. Specific DNA amplification methods for MTB showed that 55% of individuals were positive and that the incidence varied according to age at death and sampling site in the body. Radiographs were obtained from 27 individuals and revealed an association between gross pathology and the presence of MTB DNA. There was an inverse relationship between PCR positivity and MTB target sequence size. In some cases, the preservation of MTB DNA was excellent, and several target gene sequences could be detected from the same sample. This information, combined with MTB DNA sequencing data and molecular typing techniques, will enable us to study the past epidemiology of TB infection, and extends the timeframe for studying changes in molecular fingerprints. Am J Phys Anthropol 120:144-152, 2003. (C) 2003 Wiley-Liss, Inc
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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