76 research outputs found

    Unusual Beach Deposits in Oolite Carbonate Environments Mississippian and Recent

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    Thousands of small fossils were collected from unusual lenses within the Cyathophyllum Zone, Gilmore City Limestone (Mississippian) in a large quarry near Humboldt, Iowa. These rare lenses occur in an interval 1-2.5m thick that shows an extreme variability of facies. An intensive search of other Gilmore City outcrops revealed no similar lenses. The rest of the interval, outside the lenses, contained larger fossils and fossil fragments. The small fossils in the lenses are remarkably well preserved, the gastropods particularly so. Comparison of the Gilmore City Limestone with Recent oolitic deposits at Paradise Island in the Bahamas leads to the conclusion that these unusual lenses probably were a backshore deposit. The Bahamian deposits provide evidence for interpretation of these fossils as size-sorted rather than dwarfed. Early carbonate coating is hypothesized to explain the exceptional preservation of the Mississippian fossils

    A Preliminary Stratigraphic Study of the Galena Group of Winneshiek County, Iowa

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    The rocks of the Galena Group have proved to be problematic in correlation. This problem is due to a variable lithofacies development. A preliminary investigation, although based upon exposures studied just within Winneshiek County, provides a method for field identification in Iowa of stratigraphic units currently used by the Illinois State Geological Survey within Illinois. Units under consideration at this time are restricted to the Dunleith, Wise Lake, and Dubuque Formations. Methods of identification and correlation employ in part such physical features as sequences of nodular chart bands, discontinuity surfaces, and sparry calcarenite bands. Investigation has disclosed a close relationship of these three features. A composite graphic column is provided, with key identification factors, for each of the subdivisions together with reference localities where the strata under investigation may be observed in sequence

    Stratigraphy of the Dubuque Formation (Upper Ordovician) in Iowa

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    The Dubuque Formation of Upper Ordovician age crops out in the Upper Mississippi Valley. It comprises interbedded carbonate and argillaceous rocks that are approximately 35 feet thick in Iowa and Illinois, but thicken to a maximum of approximately 45 feet in southern Minnesota. Three proposed informal subdivisions: Frankville, Luana, and Littleport beds, are differentiated on the basis of bed surface topography ranging upward from nearly planar beds in the Frankville to prominently undulose surfaces in the Littleport beds. The Frankville beds represent a transition from the massive dolomite of the underlying Stewartville Member of the Wise Lake Formation to the overlying interbedded carbonate rocks and shale of the upper Dubuque. The base of the Dubuque Formation in Iowa and Minnesota is placed at a prominent, approximately 8 inch thick, carbonate bed at the base of the Frankville beds. This \u27\u27marker bed\u27\u27 provides a more precise datum for lithostratigraphic correlation than the lowest prominent shale parting employed by previous workers to identify the base of the Dubuque

    Assessment of the proliferative, apoptotic and cellular renovation indices of the human mammary epithelium during the follicular and luteal phases of the menstrual cycle

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    Introduction During the menstrual cycle, the mammary gland goes through sequential waves of proliferation and apoptosis. in mammary epithelial cells, hormonal and non-hormonal factors regulate apoptosis. To determine the cyclical effects of gonadal steroids on breast homeostasis, we evaluated the apoptotic index ( AI) determined by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling ( TUNEL) staining in human mammary epithelial cells during the spontaneous menstrual cycle and correlated it with cellular proliferation as determined by the expression of Ki-67 during the same period.Methods Normal breast tissue samples were obtained from 42 randomly selected patients in the proliferative ( n = 21) and luteal ( n = 21) phases. Menstrual cycle phase characterization was based on the date of the last and subsequent menses, and on progesterone serum levels obtained at the time of biopsy.Results the proliferation index ( PI), defined as the number of Ki-67-positive nuclei per 1,000 epithelial cells, was significantly larger in the luteal phase (30.46) than in the follicular phase (13.45; P = 0.0033). the AI was defined as the number of TUNEL-positive cells per 1,000 epithelial cells. the average AI values in both phases of the menstrual cycle were not statistically significant ( P = 0.21). However, the cell renewal index ( CRI = PI/AI) was significantly higher in the luteal phase ( P = 0.033). A significant cyclical variation of PI, AI and CRI was observed. PI and AI peaks occurred on about the 24th day of the menstrual cycle, whereas the CRI reached higher values on the 28th day.Conclusions We conclude that proliferative activity is dependent mainly on hormonal fluctuations, whereas apoptotic activity is probably regulated by hormonal and non-hormonal factors.Universidade Federal de São Paulo, Dept Gyneol, Mastol Div, São Paulo, BrazilStanford Univ, Sch Med, Dept Neurosurg, Stanford, CA 94305 USAAPC Pathol, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Gyneol, Mastol Div, São Paulo, BrazilWeb of Scienc

    Transport of organic anions and cations in murine embryonic kidney development and in serially-reaggregated engineered kidneys

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    Recent advances in renal tissue engineering have shown that dissociated, early renogenic tissue from the developing embryo can self-assemble into morphologically accurate kidney-like organs arranged around a central collecting duct tree. In order for such self-assembled kidneys to be useful therapeutically or as models for drug screening, it is necessary to demonstrate that they are functional. One of the main functional characteristics of mature kidneys is transport of organic anions and cations into and out of the proximal tubule. Here, we show that the transport function of embryonic kidneys allowed to develop in culture follows a developmental time-course that is comparable to embryonic kidney development in vivo. We also demonstrate that serially-reaggregated engineered kidneys can transport organic anions and cations through specific uptake and efflux channels. These results support the physiological relevance of kidneys grown in culture, a commonly used model for kidney development and research, and suggest that serially-reaggregated kidneys self-assembled from separated cells have some functional characteristics of intact kidneys

    Uma visão da produção científica internacional sobre a classificação internacional para a prática de enfermagem

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    A Classificação Internacional para a Prática de Enfermagem (CIPE®) é um sistema classificatório que visa padronizaruma linguagem universal para Enfermagem. Este artigo propõe identificar os estudos desenvolvidos noâmbito mundial abordando a CIPE®, categorizando-os segundo suas finalidades. Trata-se de uma revisão de literatura,em base de dados da Biblioteca Virtual em Saúde, pelo o termo “ICNP”, com abrangência até 2009. Foramencontrados 124 artigos; 65 analisados, cujo conteúdo foi agrupado em nove categorias: abordagens gerais;aplicabilidade à prática; avaliação de classificações; experiências com recursos computacionais; desenvolvimento einclusão de termos; abordagem sobre sistemas classificatórios; uso para ancorar a construção de declarações deenfermagem; traduções; e outros. Verificou-se que poucos trabalhos apresentam projetos ou avaliam resultados deaplicações práticas da CIPE®; a maioria aborda aspectos conceituais ou realiza comparações com outras classificações.Diversos trabalhos concluem sobre a adequação e relevância da CIPE®, mas apontam a necessidade de aperfeiçoamento

    Molecular biology of baculovirus and its use in biological control in Brazil

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