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1.
Arq. bras. med. vet. zootec. (Online) ; 72(2): 379-386, Mar./Apr. 2020. tab, graf
Artículo en Portugués | LILACS, VETINDEX | ID: biblio-1128266

RESUMEN

Objetivou-se avaliar o poder preditivo do modelo do National Research Council (NRC) para gado leiteiro em estimar o consumo de matéria seca (CMS) por vacas mestiças, em pastagens tropicais. Foi efetuada uma análise conjunta de cinco estudos, contemplando três forrageiras. Foram avaliadas 132 estimativas individuais do CMS observado (CMSObs), obtidas por meio do indicador externo Cr2O3. O CMS também foi predito por meio do software do NRC (CMSPred), que, por sua vez, foi abastecido com inputs referentes aos animais e ao ambiente de criação. Os valores de CMSPred (12,7±1,6kg/d) foram semelhantes aos de CMSObs (12,3±3,3kg/d). Foram obtidas as seguintes estimativas da avaliação do poder preditivo do modelo: viés médio (-0,419kg/d), coeficiente de determinação (0,029), coeficiente de correlação (0,17; P=,051), quadrado médio do erro de predição (11,844±20,034), fator de eficiência do modelo (-0,081), coeficiente de determinação do modelo (4,1032) e fator de correção do viés (0,767). A comparação entre CMSObs e CMSPred permitiu identificar a tendência de superestimação das predições se considerado o ajuste por meio de regressão robusta para o modelo linear simples sem intercepto. Nas condições avaliadas, o modelo produz predições de CMS com satisfatória exatidão, porém com baixa precisão.(AU)


The aim of the present study was to evaluate the predictive power of estimating the dry matter intake (DMI) of crossbred cows on tropical pastures by the National Research Council (NRC) equation for dairy cattle. A joint analysis of five studies covering three forages was performed in which 132 individual estimates of observed DMI obtained through Cr2O3 as a marker. DMI was also predicted from the NRC (DMIPred) software with inputs concerning animals and breeding environment of the studies used. Predicted DMIPred average values (12.7±1.6kg/d) were similar to the observed DMIObs ones (12.3±3.3kg/d). We obtained the following estimates of the evaluation of the predictive power of the model: average bias (- 0.419kg/d), coefficient of determination (0.029), Person's correlation coefficient (0.17, P= 0.051), mean square error of prediction (11,844±20,034), model efficiency factor (- 0.081), coefficient of determination (4.1032), and bias correction factor (0.767). The comparison between DMIObs and DMIPred values allowed the identification of the overestimating tendency of the predictions demonstrated by the robust regression fit of the simple linear no intercept model. Nevertheless, the model yields predictions with satisfactory accuracy, but with low precision.(AU)


Asunto(s)
Animales , Femenino , Bovinos , Pastizales , Predicción/métodos , Ingestión de Alimentos , National Academy of Sciences, U.S.
2.
Braz. j. morphol. sci ; 31(1): 14-17, 1/3/2014. ilus
Artículo en Inglés | LILACS | ID: biblio-911259

RESUMEN

Introduction: Currently, two types of atlas provide anatomical studies: those with two-dimensional images, and those compiled by interactive pictures; mostly drawn virtually. In recent decades, the development of virtual anatomical atlases has been encouraged and prioritized by both the technological advances and the need to facilitate and complement medical education. The aim of this study was to develop an interactive virtual atlas of the upper limbs. Material and Methods: A systematic dissection of three upper limbs (shoulder, arm, forearm and hand) of legally preserved cadavers in Anatomy Laboratory of São José do Rio Preto Medical School, SP (FAMERP) has been carried out. Results: A website has been developed to facilitate the learning of superficial and deep structures of the limbs comprising ten pictures showing the steps and the various structures and display devices (naming demarcated structures and text with relevant information about these). In addition, the website includes a photo gallery with subtitled images of the dissected upper limbs. Conclusion: In conclusion, virtual study of Anatomy by means of interactive-image display of dissected parts can facilitate and enhance the learning of the upper limbs.(AU)


Asunto(s)
Atlas como Asunto , Interfaz Usuario-Computador , Extremidad Superior/anatomía & histología , Realidad Virtual , Anatomía
3.
Braz. j. med. biol. res ; 42(6): 515-522, June 2009. ilus, tab, graf
Artículo en Inglés | LILACS | ID: lil-512765

RESUMEN

Future clinical applications of human embryonic stem (hES) cells will require high-yield culture protocols. Currently, hES cells are mainly cultured in static tissue plates, which offer a limited surface and require repeated sub-culturing. Here we describe a stirred system with commercial dextran-based microcarriers coated with denatured collagen to scale-up hES cell production. Maintenance of pluripotency in the microcarrier-based stirred system was shown by immunocytochemical and flow cytometry analyses for pluripotency-associated markers. The formation of cavitated embryoid bodies expressing markers of endoderm, ectoderm and mesoderm was further evidence of maintenance of differentiation capability. Cell yield per volume of medium spent was more than 2-fold higher than in static plates, resulting in a significant decrease in cultivation costs. A total of 10(8) karyotypically stable hES cells were obtained from a unitary small vessel that needed virtually no manipulation during cell proliferation, decreasing risks of contamination. Spinner flasks are available up to working volumes in the range of several liters. If desired, samples from the homogenous suspension can be withdrawn to allow process validation needed in the last expansion steps prior to transplantation. Especially when thinking about clinical trials involving from dozens to hundreds of patients, the use of a small number of larger spinners instead of hundreds of plates or flasks will be beneficial. To our knowledge, this is the first description of successful scale-up of feeder- and Matrigel™-free production of undifferentiated hES cells under continuous agitation, which makes this system a promising alternative for both therapy and research needs.


Asunto(s)
Animales , Humanos , Ratones , Técnicas de Cultivo de Célula/métodos , Diferenciación Celular/fisiología , Dextranos/farmacología , Células Madre Embrionarias/citología , Técnicas de Cultivo de Célula/instrumentación , Diferenciación Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Citometría de Flujo , Inmunohistoquímica
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