1,721,021 research outputs found
Cancerogénesis química experimental en anfibios
Get PDFFil: Matos, Elena L.. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina
Cancerogénesis química experimental en anfibios
No full textFil: Matos, Elena L.. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina
Teratogenic effects induced in tail of Bufo arenarum tadpoles following treatment with carcinogens
No full textSi descrivono gli effetti teratogeni indotti nella coda del girino delBufo arenarum in uno stadio premetamorfosico, come conseguenza dell'impianto di cristalli di idrocarburi cancerigeni. Tanto il MC come il BP o il DMBA producono alette sopranumerarie che ripetono le strutture istologiche delle alette normali; ed inoltre il DMBA induce la formazione di una seconda notocorda parallela alla normale.Fil: Sacerdote de Lustig, Eugenia. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Oncología "Ángel H. Roffo"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Matos, Elena L.. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Oncología "Ángel H. Roffo"; ArgentinaUnidad documental simpl
Evaluation of the Response of Bufo arenarum larvae to 20-Methylcholanthrene
No full textWe inoculated 214 animals with a 20-Methylcholanthrene suspension in olive oil. The first reaction, 3 to 9 days after inoculation, is an intensive epithelial hyperplasia with cellular disorientation, anisocytosis and increased mitotic activity limited to the site of inoculation. Superimposed on this background of epithelial disorganization an inflammatory process is observed both in treated and control animals. Later a perforation of the basal membrane can occur with invasion of muscle and mesonephros or with pseudotumoral nodular formations. In other cases a papillomatous formation is observed. After 20 days a regressive phase of these processes sets in. The larvae of Bufo arenarum respond to 20-Methylcholanthrene treatment very promptly.Fil: Matos, Elena L.. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Oncología "Ángel H. Roffo"; ArgentinaFil: Sacerdote de Lustig, Eugenia. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Oncología "Ángel H. Roffo"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaUnidad documental simpl
Teratogenic effects of carcinogen implantation in a regenerative field in Bufo arenarum tadpoles
No full textImplantation of 20‐methylcholanthrene (MC), 3,4 benzopyrerne (BP), and 7,12‐dimethylbenz [a] anthracene in the tail of Bufo arenarum tadpoles induced toratogenic effects as well as lymphocyte or pleomorphic cell nodule formation. The development of nodules was modified by a regenerative field. The incidence and intensity of the teratogenic effects (supernumerary fins, accessory notochords—the latter reported here for the first time in amphibia) were enhanced by a regenerative field caused by tail amputation. MC and BP produced only supernumerary fins, and did so infrequently; whereas DMBA produced both defects, and in relative large frequencies.Fil: Matos, Elena L.. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Oncología "Ángel H. Roffo"; ArgentinaFil: Sacerdote de Lustig, Eugenia. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Oncología "Ángel H. Roffo"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaUnidad documental simpl
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Morphological Alterations Induced in Organ Cultures of Human Fetal Trachea and Bronchi by Diethylnitrosamine (DEN)
No full textHuman fetal respiratory tract was exposed to the action of N-nitrosodiethyl-amine (DEN), a potent carcinogen for other species, in an organ culture system. The dose of 15 μl/ml DEN elicited an intensive proliferative response of the respiratory epithelium while higher doses were toxic.Fil: Matos, Elena L.. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Oncología "Ángel H. Roffo"; ArgentinaFil: Bal, Elisa Dora. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Oncología "Ángel H. Roffo"; ArgentinaFil: Sacerdote de Lustig, Eugenia. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Oncología "Ángel H. Roffo"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaUnidad documental simpl
Variations on the Author
Get PDF“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
Get PDFWe 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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