1,720,960 research outputs found
The role of ras gene expression and transforming growth factor alpha production in the etiology and progression of rodent and human breast cancer
No full textOver-expression of the epidermal growth factor receptor in human breast cancer cells fails to induce an estrogen-independent phenotype
No full textTransformation of mouse mammary epithelial cells with the Ha-ras but not with the neu oncogene results in a gene dosage-dependent increase in transforming growth factor-alpha production
No full textDifferential growth factor expression in transformed mouse NIH‐3T3 cells
No full textThe expression of growth factor‐specific mRNA transcripts and the presence of biologically active growth factors in the conditioned medium and in the cell extracts from mouse NIH‐3T3 cells transformed by different oncogences (Ki‐ras, mos, src, fms, fes, met, and trk), by DNA tumor virus (SV40), or by a chemical carcinogen (N‐nitrosomethylurea) were studied. In contrast to NIH‐3T3 cells or simain virus 40 (SV40)‐transformed 3T3 cells, all the other transformed NIH‐3T3 cell lines express a 4.5 kb transforming growth factor‐α (TGFα)‐specific mRNA transcript and secreted immunoreactive and biologically active TGFα ranging from 100 to 225 ng/108 cell/48 h. In addition, in the transformed cell lines that were secreting elevated levels of biologically active TGFα, there was a 75–95% reduction in the total number of epidermal growth factor receptors on these cells. A 2.6 kb TGFβ mRNA transcript and TGFβ protein in the conditioned medium (30–140ng/108 cells/48h) was also detected in those lines expressing TGFα. Basic fibroblast growth factor‐like activity (11–50 ng/108 cells) was detected in the cell lysates from NIH‐3T3 cells transformed with N‐nitrosomethylurea or with trk, where expression of specific 6.9 and 3.9 kb mRNA transcripts for basic fibroblast growth factor could also be found. B chain (c‐sis) expression of platelet‐derived growth factor was present only in trk‐transformed NIH‐3T3 cells in which specific c‐sis 6.5 and 4.6 kb transcripts were identified. In contrast, platelet‐derived growth factor A chain expression of 2.9 and 2.3 kb transcripts was found in ras‐, met‐, mos‐, and fms‐transformed NIH‐3T3 cells. These results suggest that the expression of different sets of growth factors is controlled in part by structurally distinct groups of transforming genes. Copyright © 1990 Wiley‐Liss, Inc
Stromal influences on transformation of human mammary epithelial cells overexpressing c-myc and SV40T
No full textThe int-2 gene product acts as a growth factor and substitutes for basic fibroblast growth factor in promoting the differentiation of a normal mouse mammary epithelial cell line
No full textThe mouse int-2 gene exhibits basic fibroblast growth factor activity in a basic fibroblast growth factor-responsive cell line
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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
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