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Expresión de factor estimulante de colonias-1 (CSF-1), proteína quimiotáctica de monocitos-3 (MCP-3) y catepsina-K en periodontitis apical crónica y tejido periapical sanoOsorio Alfaro, Constanza Andrea January 2009 (has links)
Trabajo de Investigación Requisito para optar al Título de Cirujano Dentista / Autor no autoriza el acceso a texto completo de su documento / Introducción: La periodontitis apical crónica (PAC) es una patología
inmunoinflamatoria de origen infeccioso que se caracteriza por la destrucción del
tejido óseo periapical y está asociada a la expresión de diversos mediadores
inflamatorios. MCP-3 proteína quimiotáctica de monocitos, CSF-1 factor que
estimula la diferenciación de células precursoras de osteoclastos y Catepsina K,
enzima asociada a la destrucción ósea, son moléculas que debido a su función
podrían estar relacionadas con la osteólisis apical presente en los dientes con
PAC. Por esta razón, el objetivo de este estudio fue caracterizar la expresión de
CSF-1, MCP-3 y Catepsina K en quiste radicular inflamatorio (QRI), granuloma
periapical (GP) y en tejido periapical sano.
Materiales y Métodos: Se seleccionaron 20 individuos con diagnóstico
clínico de PAC e indicación de extracción. Luego de la exodoncia, las lesiones
periapicales (LPAs) fueron biopsiadas y se realizó el diagnóstico anátomopatológico.
Posteriormente se realizó la tinción inmunohistoquímica, para
finalmente examinar los cortes en un microscopio óptico.
Resultados: De un total de 20 muestras, 5 se diagnosticaron como QRI, 7
correspondieron a GP y 7 LPA sanos. La expresión de MCP-3 se observó en QRI
epitelio, endotelio e infiltrado inflamatorio; en GP su distribución fue similar,
aunque no se identificó en endotelio vascular. CSF-1 se expresó en QRI a nivel
del epitelio, células mesenquimales, endotelio e infiltrado inflamatorio, mientras
que en GP se identificó en endotelio e infiltrado inflamatorio. Catepsina K se
observó en epitelio, células mesenquimales e infiltrado inflamatorio de QRI;
mientras que en GP se localizó en células mesenquimales e infiltrado inflamatorio.
No se observó inmunoreactividad en tejido periapical sano.
Conclusiones: MCP-3, CSF-1 y Catepsina K se expresan en forma similar
en QRI y GP, mientras que no se observaron en tejido periapical sano. Nuestros
resultados sugieren que existe participación de estos mediadores en la
patogénesis de la PAC.
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Cognitive processing in complex situations : the dynamics of information flowLee, Robert Bruce January 1974 (has links)
The thesis describes and develops a new theoretical approach to the study of human cognitive processing performance in complex situations, so this approach utilises and integrates existing theoretical and empirical data from a number of traditionally separate areas of information processing psychology, such as cognition, perception, memory, imagery, skill and vigilance. Contemporary cognitive psychology considers perception, memory and imagery as functionally inter-related and inter-dependent processes characterised by active, constructive, conscious information processing. In the present thesis the implications of this view are extended, in that this processing is considered to occupy the cognitive processing capacity of the subject in qualitatively the same way as does normal decision-making, problem-solving, or conscious Internalised thought processing of any kind. The theoretical approach of the thesis stresses and accepts the functional inter-relationship and inter-dependence of the various higher mental processes, and is primarily concerned with the sustained dynamic performance properties of the total system. The nature of the research emphasis and direction of the thesis originates from the author's direct concern with applied problems resulting from the increasing cognitive load imposed upon human operators in present complex man-machine systems, such as jet aircraft, for example. Performance failure of the human operator in these systems often has very serious consequences. There is a critical lack of knowledge regarding the fundamental nature and limitations of human information processing in such situations. The basic motivation behind the work reported in the thesis was that, in order to study meaningfully the relevant aspects of the applied situation, further pure research, both theoretical and empirical, had to be undertaken to clarify particular issues. A new conceptual approach to vigilance-type situations is suggested by the theory developed in the thesis, A task was devised in which the signals to be detected were clearly visible, but embedded at random in complex visual patterns (photographs). These patterns were presented on a television screen at regular intervals, over 600 times to subjects during a single testing session. At each of these presentations subjects had to respond with respect to the identification of the picture shown; and to the presence or absence of a signal within it. From the theory it was predicted that where the complex pattern remained the same throughout the testing session, signal detection performance would show a typical vigilance decrement. However, when the set of possible pictures in which the signal may or may not be embedded is vastly increased, and the subject' has to respond at each event in the manner described, it was predicted that signal detection performance would be significantly improved in relation to the single picture condition. These predictions were empirically confirmed at a highly significant level. (On the basis of visual signal-to-noise ratios only, a signal detection analysis of the experimental situation would predict a result opposite to that actually obtained in the experiment). A computer simulation program based on fundamental theoretical ideas outlined in the thesis was developed. The program was used to simulate the vigilance experiment reported in the dissertation. The purpose and implications of the use of this technique as an applied research tool are discussed. The final chapter discusses the results achieved, and outlines the proposed application of the theoretical ideas, and empirical results of the research to the cognitive load problems of human operators in real man-machine systems, in particular aircrew flying advanced jet aircraft.
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An analysis of selected aspects of demographic change in the border counties of Scotland, 1755-1961Soulsby, Eve M. January 1971 (has links)
No description available.
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Idiographic Emotion Structures in Subjective Emotional ExperiencesJanuary 2017 (has links)
abstract: Psychological theories often reduce descriptions of people’s emotional experiences to a small number of underlying dimensions that capture most of the variation in their responses. These underlying dimensions are typically uncovered by comparing the self-reported emotions of many individuals at one specific time point, to infer a single underlying structure of emotion for all people. However, theoretical work suggests that underlying dimensions uncovered in this way may not hold when modeling how people change over time. Individuals may differ not just in their typical score on a given dimension of emotion, but in what dimensions best characterize their patterns of emotional experience over time. In this study, participants described two emotional events per day for 35 days, and analyses compared individualized structures of emotion to those generated from many people at one point in time. Analyses using R-technique factor analysis, which compares many people at one time point, most often uncovered a two-factor solution corresponding to positivity and negativity dimensions - a solution well-established in the literature. However, analyses using P-technique factor analysis, which compares many emotional events for one person, uncovered a broader diversity of underlying dimensions. Individuals needed anywhere from one to five factors to best capture their self-reported emotions. Further, dimensions specifically related to romantic relationships were much more common when examining the experiences of individuals over time. This suggests that external factors, such as pursuing or being in a romantic relationship, might lead to a qualitative shift in how emotions are experienced. Research attempting to characterize emotion dynamics, including those attempting to help people shift or regulate their emotions, cannot assume that typical two dimensional structures of emotional experience apply to all people. Instead we must account for how individuals describe their own emotional experiences. / Dissertation/Thesis / Doctoral Dissertation Psychology 2017
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Rol del Factor de Crecimiento Nervioso (NGF) en la Regulación de la Proliferación y Angiogénesis del OvarioLozada González, Patricia Emita January 2006 (has links)
Memoria para optar al título de Bioquímico / El factor de crecimiento nervioso (NGF) es una neurotrofina, que inicialmente fue
descrita en el cerebro, y que en los últimos años ha adquirido importancia, debido a que actúa en
sitios no-neuronales, entre ellos el ovario, donde se ha encontrado que NGF participa en el
desarrollo ovárico, proliferación y diferenciación de células somáticas y en la esteroidogénesis.
Una de las etapas importantes que ocurren durante el desarrollo folicular y del cuerpo lúteo es la
angiogénesis, una de las moléculas importantes en este proceso es el factor de crecimiento de
endotelio vascular (VEGF).
NGF aumenta la expresión de VEGF en diversos tipos celulares. VEGF es regulado en
forma directa por el gen inducible por hipoxia (HIF-1) y en forma indirecta por c-Myc. Además
c-Myc, es un gen involucrado en la proliferación celular. En este trabajo se investigó el rol que
cumple NGF en la regulación de VEGF y la proliferación celular. Para este fin se utilizaron
células de granulosa humana, provenientes de pacientes del programa de fertilización asistida,
las cuales se cultivaron por 2, 4, 8 y 18 horas con NGF (50 ng/ml). Se midieron los niveles del
ARNm de VEGF, c-Myc e HIF-1 alfa por RT-PCR. En este trabajo el ARNm de las isoformas
de VEGF 165 y 121 aumentaron a las 4 y 8 horas respectivamente, los niveles del ARNm de
HIF-1 alfa se mantuvieron inalterados a todos los tiempos estudiados. Los niveles de ARNm de
c-Myc aumentaron a las 8 y 18 horas por efecto de NGF. Por Inmunocitoquímica se determinó
Ki67, un marcador de proliferación celular. La proteína Ki67 aumentó a las 8 y 18 horas por
efecto de NGF, concordando con la expresión génica de c-Myc.
Los resultados indican que NGF presenta la capacidad de aumentar, tanto la expresión
del ARNm de VEGF, como la proliferación en forma independiente, y que este aumento en la
proliferación sería en una etapa posterior al alza de VEGF y que probablemente el VEGF
expresado en las células de granulosa humana en cultivo, éste involucrado en la proliferación
directamente, esto podría suponer que una falla en la producción de NGF por parte del folículo podría llevar a éste a un crecimiento y maduración deficiente, debido a que no ocurriría una
angiogénesis y proliferación adecuada / The nerve growth factor (NGF) is a neurothrophin, initially described in the brain, that
has acquired importance in the last few years, because it has several functions in non-neuronal
tissues. One of these tissues is the ovary, where NGF participates in the ovarian development,
proliferation and differentiation of somatic cells and steroidogenesis. Angiogenesis is an
essential stage during follicular and luteal development, and one of the most important
molecules in this process is the vascular endothelial growth factor (VEGF).
NGF increases VEGF expression in different cell types. VEGF is directly regulated by
hypoxia inducible factor-1(HIF-1) and indirectly by c-Myc. c-Myc is also a gene involved in cell
proliferation. This work investigated the role of NGF in regulating VEGF and cell proliferation.
To this aim, granulosa cells obtained from patients undergoing in vitro fertilization were cultured
for 2, 4, 8 and 18 hours with NGF (50 ng/ml). The levels of VEGF, c-Myc and HIF-1alpha
mRNA were evaluated by RT-PCR. mRNA for VEGF 165 and VEGF 121 isoforms increase at 4
and 8 hours respectively. HIF-1alpha mRNA levels did not change at any time. NGF (50ng/ml)
induces c-Myc mRNA increase at 8 and 18 hours. Ki67 protein, a cell proliferation marker, was
determined by immunocytochemistry. Ki67 protein increases at 8 and 18 hours with NGF
stimulation, and no change was observed at 4 hours, agreeing with the genic expression of c-
Myc.
The results indicate that NGF is able to increase VEGF mRNA expression and cell
proliferation by independent ways, and that the increase in the proliferation would be a later
stage to VEGF's rise. It is probable that the VEGF expressed in cultured human granulosa cells
acts directly on cell proliferation, suggesting that fails in follicular NGF production might induce a deficient follicular growth and maturation, due to impairment in angiogenesis and cell
proliferation
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Aplicación de factores de inversión: value, volatility, quality y momentum en la Bolsa de Valores de Lima / Application of investment factors: value, volatility, quality and momentum in the Lima stock exchangeJacinto Gutarra, Jorge Lorenzo, Agüero Baldeon, Luis Ricardo 20 July 2019 (has links)
En la presente tesis de aplicación de Factores de Inversión: Value, Volatility, Quality y Momentum en la Bolsa de Valores de Lima (BVL), se utilizó como Benchmark el Índice General de la Bolsa de Valores de Lima (IGBVL), conformada por 39 valores, que mediante filtros de liquidez y tiempo de cotización en la Bolsa quedaron 27, por falta de datos se llegó finalmente a 25 valores.
Luego, se definen las variables de cada factor. Para el Factor Value: PER y PBV (Price to Book). Para el Factor Momentum la variable momento de los precios. Para el Factor Quality la variable ROE. Para el Factor Volatility la variable Volatilidad total. Seguidamente, se aplican procedimientos para analizar las variables de los cuatro factores a los datos para escoger aquellos que puedan superar al Benchmark.
Finalmente, se demuestra que en los últimos diez años que el portafolio, con valores que tengan un ratio PER (Variable del Factor Value) inferior al promedio de la Bolsa y actualizando la cartera de manera trimestral, tiene un mejor rendimiento que el Benchmark y el portafolio conformado por empresas con ratio PER superior al promedio de la Bolsa. Los resultados han sido enmarcados en un nivel de confianza al 95%. / In this thesis of application of Investment Factors: Value, Volatility, Quality and Momentum in the Lima Stock Exchange (BVL), the General Index of the Lima Stock Exchange (IGBVL) was used as Benchmark, consisting of 39 values, which by means of liquidity filters and time of quotation in the Stock Exchange were 27, due to lack of data, finally 25 values were reached.
Then, the variables of each factor are defined. For the Value Factor: PER and the Price to Book. For the Momentum Factor the price momentum variable. For the Quality Factor, the variable ROE. For the Volatility Factor the variable Total Volatility. Next, procedures are applied to analyze the variables of the four factors to the data to choose those that can surpass the Benchmark.
Finally, it is shown that in the last ten years that the portfolio, with values that have a PER (Variable Value Factor) ratio lower than the average of the Exchange and updating the portfolio quarterly, has a better performance than the Benchmark and the portfolio made up of companies with a PER ratio higher than the average of the Stock Exchange. The results have been framed at a 95% confidence level. / Trabajo de investigación
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Factores claves en la administración del tiempoAlania Vera, Ricardo Humberto 12 September 2013 (has links)
Explica que la administración del tiempo implica un control de las emociones y ansiedades de la persona, puesto que el ser humano es influenciable y sensible a los hechos que suceden en nuestro contexto, tanto personal como laboral. Por tanto, indica que la inteligencia emocional es un factor determinante para tomar mejor decisiones, lo cual devendrá en el uso eficiente del tiempo. Asimismo, agrega que la planificación del tiempo es importante, así como programar las contingencias.
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Spurious Thrombocytopenia Produced by the Interaction of Rheumatoid Factor With Antiplatelet AntibodyPoskitt, Thomas R., Poskitt, Paula K.F. 01 January 1985 (has links)
A patient had spurious thrombocytopenia resulting from a mechanism not previously described. Whereas in prior reports the in vitro phenomenon of platelet clumping has been effected by either EDTA‐dependent or temperature‐dependent antibodies capable of direct platelet agglutination, neither the IgG nor the IgM fractions of this patient's serum demonstrated such activity. However, agglutination was produced by incubating allogeneic platelets with the IgG fraction followed by a room temperature incubation with the rheumatoid factor‐positive IgM fraction. The data support a new mechanism for spurious thrombocytopenia resulting from the interaction of a cold‐reactive rheumatoid factor with antiplatelet antibody.
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Pre-Analytical and Analytical Variables Affecting the Measurement of Plasma-Derived Microparticle Tissue Factor ActivityLee, R. D., Barcel, D. A., Williams, J. C., Wang, J. G., Boles, J. C., Manly, D. A., Key, N. S., MacKman, N. 01 January 2012 (has links)
Introduction: Elevated levels of tissue factor positive (TF +) microparticles (MPs) are observed in plasma from a variety of patients with an increased risk of thrombosis. We and others have described the measurement of TF activity in MPs isolated from plasma. The aim of this study was to investigate the effects of pre-analytical and analytical variables on TF activity of MPs isolated from blood of healthy volunteers either untreated or treated ex vivo with bacterial lipopolysaccharide. Materials and methods: We evaluated the following parameters: use of different centrifugation speeds to isolate the MPs; comparison of TF activity of MPs isolated from platelet poor plasma versus platelet free plasma; effect of freeze/thaw on MP TF activity; and comparison of the MP TF activity assay with the measurement of TF protein by ELISA or flow cytometry. Results: MPs prepared from platelet poor plasma by centrifugation at 20,000 × g or 100,000 × g for 15 minutes had similar levels of TF activity. However, significantly less TF activity was found in MPs isolated from platelet free plasma compared with platelet poor plasma. Interestingly, freeze/thawing of the plasma showed donor to donor variation in MP TF activity, with a moderate increase in some individuals. Conclusion: TF + MPs can be quantitatively isolated from platelet poor or platelet free plasma by centrifugation at 20,000 × g for 15 minutes. Measurement of MP TF activity in plasma may be used to detect a prothrombotic state in patients with various diseases.
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Exploring the Effects of a Corticotropin Releasing Factor (CRF) Receptor Antagonist on Habit ExpressionHaines, Kari 12 1900 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Some individuals with alcohol use disorder (AUD) continue to drink because they have developed a habit in which they are not considering the consequences of their actions. Habitual actions persist despite changes in reward and are often studied using devaluation procedures. Stress hormones, such as corticotropin releasing factor (CRF), have been linked to AUD when examining binge-like drinking and withdrawal in rodents. Stress has been examined in the switch from goal-directed to habitual behavior, and CRF has often mimicked the effects of stress exposure. This study looked at the possible direct effects of CRF on habit expression in rats using an operant paradigm. Finding possible novel mechanisms of habit could create an avenue for future novel treatment options. Female and male Long Evans rats were trained on a variable interval schedule using sucrose as a reward. Rats then underwent devaluation procedures including both sensory-specific satiety and conditioned taste aversion (CTA) to test for habitual behaviors. Prior to an extinction session post-CTA, animals were treated with either 20 mg/kg R121919, a CRF1 receptor antagonist, or vehicle. A second extinction session was conducted where animals received the alternative treatment. Lever presses were recorded as a measure of goal-directed or habitual behavior. Sensory-specific satiety devaluation tests revealed that animals were not sensitive to devaluation. This was further supported by both post-CTA extinction sessions. R121919 had no effect on lever pressing in either devalued or valued groups. Further research is needed to explore how a CRF receptor antagonist may affect habit formation or the transition from goal-directed to habit behaviors. Future studies should also examine any possible interaction effects CRF may have with alcohol or stress on habitual behaviors.
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