1,721,085 research outputs found
Acute hepatitis caused by green tea infusion: a case report
No full textThe green tea is obtained by an unfermented process of leaves of Camellia sinensis and the main chemical components are polyphenols, particularly epigallocatechin gallate and epicatechin gallate that could be associated to adverse hepatic reactions. We present a case of acute hepatitis caused by the use of green tea. A 62-year-old woman was hospitalized because of the persistent high levels of liver function tests. After the hospitalization a lot of instrumental exams and blood checks were performed. The presence of heavy metals in the used green tea infusions was performed using an inductively coupled-plasma mass spectrometry; high performance liquid chromatography-electro spray ionization-mass spectrometry analysis was done to characterize the metabolite profiles of the infusions of green tea. The blood check showed in particular alanine aminotransferase (780 U/L) and total bilirubin (1.15 mg/dL) levels abnormal. The abdominal echography and other blood parameters were normal, but liver biopsy described a “drug toxic damage”. Every day over the previous 9 months the patient drank two or three cups of several brands of green tea infusions and she stopped this behavior when abdominal pain was persistent. Her medical history didn’t report the use of other drugs or toxic products. After four months of stopping the use of green tea infusions, the liver function tests were normalized. The presence of heavy metals in tea infusion cannot justify the observed liver toxicity in our patient. Instead, the highest levels of epigallo catechin methyl gallate derived from epigallocatechin gallate observed in the sample consumed by the patient, arise a possible correlation between the catechins in green tea and the hepatotoxic effect. It is conceivable that the mechanism of damage can be idiosyncratic-metabolic or allergic
The influence of diet on intra and inter-individual variability of urinary excretion of arsenic species in Italian healthy individuals
No full textBiomarkers of exposure to aromatic hydrocarbons and methyltert-butyl ether in petrol station workers
No full textField comparison of a personal cascade impactor sampler, an optical particle counter and CEN-EU standard methods for PM10, PM2.5 and PM1 measurement in urban environment
No full textThe need to evaluate personal exposure to aerosol instead of simply measuring outdoor concentrations is now evident. In this connection, Personal Cascade Impactor Samplers (PCIS) and Optical Particle Counters (OPC) are likely to be widely deployed in the near future because their characteristic light weight and low cost make them suitable for the purpose by minimizing interferences in human activities. The study here presented assesses the performances of the two aforementioned instruments by making a comparison with CEN-EU standardized procedures in 24h concurrent measurements of urban PM10, PM2.5 and PM1. The comparison between PM concentrations measured by OPC and CEN-UE standard procedure showed an unsatisfactory agreement: systematic differences, dependent on PM concentration, were evidenced with an underestimation of PM by OPC in the days with low concentrations and an overestimation at higher levels of PM concentration. On the contrary, PCIS can be considered statistically equivalent to CEN-EU standard methods for the determination of PM10, PM2.5 and PM1 with 95% confidence level except that systematic errors in the determination of water soluble inorganic ions (ion chromatography) and some relevant metals (ICP-MS) were evidenced, which could be mainly attributed to a different size cut-off and particle bouncing-off phenomena inside the multi-stage sampler. However, the seasonal mean concentrations of those species measured with PCIS and CEN-EU standard methods were substantially comparables. Thus, PCIS can be considered reliable in studies of PM characterization focused on personal exposure and effects of urban aerosol
Determination of hexavalent chromium in exhaled breath condensate and environmental air among chrome plating workers
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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
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