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    Transforming activity of DNA extracted from BKV-transformed hamster cells after passages in culture

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    Primary fetal rat fibroblasts (FRF cells) were transfected with DNA extracted from BKV-transformed hamster kidney cells at low passage after transformation (HKBKlp cells) and at high passage after transformation (HKBKhp cells). Two transformed rat cell lines were obtained, FRF-DNA-HKBKlp cells and FRF-DNA-HKBKhp cells, transformed by DNA extracted from HKBKlp cells and HKBKhp cells, respectively. They were characterized by a number of biological properties and by tumorigenicity and metastatic ability in newborn hamsters. The two transformed FRF cell lines exhibited exactly inverted properties in comparison with HKBK cells, in particular FRF-DNA-HKBKlp cells showed a low level of nuclear T antigen and a diffuse appearance of TSTA at the cell surface, whereas FRF-DNA-HKBKhp cells demonstrated a high level of T antigen and the capping of TSTA in the cell membrane. The tumorigencity and the metastatic ability were greater with FRF-DNA-HKBKlp cells, while FRF-DNA-HKBKhp cells appeared to be less tumorigenic and metastatic in newborn hamsters

    Decrease of cellular growth potential in "in vitro" culture of amnions with premature rupture of membranes

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    The "in vitro" cellular growth of 8 amniotic membranes from preterm deliveries with premature rupture of membrane (PROM) in absence of risk factors as cervical or vaginal infection (microbiologic negativity), cervical incontinence and other mechanical factors, was compared with cellular growth of 9 amnions from preterm deliveries without PROM. Amniotic membranes were set up in the Eagle basal medium with Earle salts and heat-inactivated fetal bovine serum (10%), gentamicin 50 micrograms/ml and amphotericin B 0.5 micrograms/ml. The results suggested that the growth potential of the cells (epithelial cells and fibroblasts) obtained from amnions with PROM was lower than that of cells obtained from amnions without PROM. We postulated that the premature rupture of membranes in patients without risk factors for PROM, would be conditioned by an intrinsic decrease of cellular growth potential

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The 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

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    “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

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    We 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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