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1.
Pharmacol Biochem Behav ; 20(5): 731-8, 1984 May.
Artículo en Inglés | MEDLINE | ID: mdl-6146144

RESUMEN

Tonic immobility in chickens was influenced by a variety of drugs that act on the adrenergic neurochemical system of the body. Alpha 1 agonists such as methoxamine and phenylephrine produced decreases in the duration of immobility, although the former compound also caused a significant increase in the immobility response at high dosages. Alpha 2 agonists such as clonidine, naphazoline, and guanfacine enhanced the duration of immobility, but clonidine also produced an apparent reversal of this effect at high dosages. Subsequent experiments examined more fully the biphasic effects by methoxamine and clonidine on tonic immobility through interactions with alpha antagonists. Yohimbine, an alpha 2 blocker, attenuated the duration of immobility, either alone or in conjunction with various dosages of methoxamine. Prazosin, an alpha 1 blocker, had no direct effect on tonic immobility, but potentiated the duration of the response when given in conjunction with various dosages of methoxamine. When these antagonists were given in conjunction with clonidine, yohimbine reduced immobility durations, while prazosin had no apparent effect on this response. These results are discussed in terms of the relative contributions of the alpha 1 and alpha 2 adrenoceptors to the duration of the immobility response.


Asunto(s)
Agonistas alfa-Adrenérgicos/farmacología , Antagonistas Adrenérgicos alfa/farmacología , Conducta Animal/fisiología , Animales , Pollos , Clonidina/farmacología , Guanfacina , Guanidinas/farmacología , Metoxamina/farmacología , Nafazolina/farmacología , Fenilacetatos/farmacología , Fenilefrina/farmacología , Prazosina/farmacología , Restricción Física , Factores de Tiempo , Yohimbina/farmacología
2.
Math Popul Stud ; 2(3): 209-27, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-12283028

RESUMEN

"Official forecasts of mortality depend on assumptions about target values for the future rates of decline in mortality rates. Smooth functions connect the jump-off (base-year) mortality to the level implied by the targets. Three alternative sets of targets are assumed, leading to high, middle, and low forecasts. We show that this process can be closely modeled using simple linear statistical models. These explicit models allow us to analyze the error structure of the forecasts. We show that the current assumption of perfect correlation between errors in different ages, at different forecast years, and for different causes of death, is erroneous. An alternative correlation structure is suggested, and we show how its parameters can be estimated from the past data. The effect of the level of aggregation on the accuracy of mortality forecasts is considered." The geographical focus is on the United States. (SUMMARY IN FRE)


Asunto(s)
Factores de Edad , Causas de Muerte , Predicción , Modelos Teóricos , Mortalidad , Proyectos de Investigación , Estadística como Asunto , Américas , Demografía , Países Desarrollados , América del Norte , Población , Características de la Población , Dinámica Poblacional , Investigación , Estados Unidos
4.
J Am Stat Assoc ; 86(416): 839-63, 1991 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-12155391

RESUMEN

"We describe a methodology for estimating the accuracy of dual systems estimates (DSE's) of population, census estimates of population, and estimates of undercount in the census. The DSE's are based on the census and a post-enumeration survey (PES). We apply the methodology to the 1988 dress rehearsal census of St. Louis and east-central Missouri and we discuss its applicability to the 1990 [U.S.] census and PES. The methodology is based on decompositions of the total (or net) error into components, such as sampling error, matching error, and other nonsampling errors. Limited information about the accuracy of certain components of error, notably failure of assumptions in the 'capture-recapture' model, but others as well, lead us to offer tentative estimates of the errors of the census, DSE, and undercount estimates for 1988. Improved estimates are anticipated for 1990." Comments are included by Eugene P. Ericksen and Joseph B. Kadane (pp. 855-7) and Kenneth W. Wachter and Terence P. Speed (pp. 858-61), as well as a rejoinder by Mulry and Spencer (pp. 861-3).


Asunto(s)
Censos , Recolección de Datos , Métodos , Crecimiento Demográfico , Proyectos de Investigación , Estadística como Asunto , Américas , Países Desarrollados , América del Norte , Características de la Población , Investigación , Estados Unidos
5.
J Am Stat Assoc ; 80(390): 306-14, 1985 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12340317

RESUMEN

"Errors in population forecasts arise from errors in the jump-off population and errors in the predictions of future vital rates. The propagation of these errors through the linear (Leslie) growth model is studied, and prediction intervals for future population are developed. For U.S. national forecasts, the prediction intervals are compared with the U.S. Census Bureau's high-low intervals." In order to assess the accuracy of the predictions of vital rates, the authors "derive the predictions from a parametric statistical model and estimate the extent of model misspecification and errors in parameter estimates. Subjective, expert opinion, so important in real forecasting, is incorporated with the technique of mixed estimation. A robust regression model is used to assess the effects of model misspecification."


Asunto(s)
Demografía , Predicción , Métodos , Modelos Teóricos , Reproducibilidad de los Resultados , Proyectos de Investigación , Estadística como Asunto , Américas , Países Desarrollados , Países en Desarrollo , América del Norte , Investigación , Estados Unidos
6.
J Am Stat Assoc ; 85(411): 609-16, 1990 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12155387

RESUMEN

"The Office of the Actuary, U.S. Social Security Administration, produces alternative forecasts of mortality to reflect uncertainty about the future.... In this article we identify the components and assumptions of the official forecasts and approximate them by stochastic parametric models. We estimate parameters of the models from past data, derive statistical intervals for the forecasts, and compare them with the official high-low intervals. We use the models to evaluate the forecasts rather than to develop different predictions of the future. Analysis of data from 1972 to 1985 shows that the official intervals for mortality forecasts for males or females aged 45-70 have approximately a 95% chance of including the true mortality rate in any year. For other ages the chances are much less than 95%."


Asunto(s)
Estudios de Evaluación como Asunto , Predicción , Modelos Teóricos , Mortalidad , Probabilidad , Proyectos de Investigación , Factores Sexuales , Estadística como Asunto , Américas , Demografía , Países Desarrollados , América del Norte , Población , Características de la Población , Dinámica Poblacional , Investigación , Estados Unidos
7.
Stat Report ; 81(8): 377-81, 1981.
Artículo en Inglés | MEDLINE | ID: mdl-12264999

RESUMEN

PIP: The authors summarize the highlights of a 1980 report prepared by the Panel on Small-Area Estimates of Population and Income to evaluate the procedures used by the U.S. Bureau of the Census in making post-censal estimates of population and per capita income for local areas.^ieng


Asunto(s)
Demografía , Estudios de Evaluación como Asunto , Crecimiento Demográfico , Estadística como Asunto , Américas , Países Desarrollados , Geografía , Renta , América del Norte , Población , Densidad de Población , Investigación , Estados Unidos
8.
J Am Stat Assoc ; 88(423): 1,080-91, 1993 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12155394

RESUMEN

"In July 1991 the [U.S.] Census Bureau recommended to its parent agency, the Department of Commerce, that the 1990 census be adjusted for undercount. The Secretary of Commerce decided not to adjust, however. Those decisions relied at least partly on the Census Bureau's analyses of the accuracy of the census and of the proposed undercount adjustments based on the Post-Enumeration Survey (PES).... This article describes the total error analysis and loss function analysis of the Census Bureau. In its decision not to adjust the census, the Department of Commerce cited different criteria than aggregate loss functions. Those criteria are identified and discussed."


Asunto(s)
Censos , Estudios de Evaluación como Asunto , Política , Proyectos de Investigación , Estadística como Asunto , Américas , Países Desarrollados , América del Norte , Características de la Población , Investigación , Estados Unidos
9.
Cancer Detect Prev ; 19(4): 374-80, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-7553680

RESUMEN

Since 1974, and as of March, 1993, we have used T/Tn antigen vaccine in safe, specific, effective, long-term intradermal vaccination against recurrence of advanced breast carcinoma (CA). Staging is by the pathologic TNM system. Treatment is ad infinitum. Of 19 consecutive breast carcinoma patients vaccinated, six Stage IV, six Stage III, and seven Stage II all survived > 5 years postoperatively. Three Stage III, three Stage IV, and five Stage II patients (i.e., 11) survived > 10 to > 18 years. Five others are alive but have not reached 10 years; three of them have no evidence of disease (NED). Three patients died of CA before reaching 10 years. An additional three breast CA patients are being treated for > 2 years, but, < 5 years postoperatively, they are NED. The vaccination are presented as a delayed-type hypersensitivity reaction with significant inflammation with increase of helper T lymphocytes and decrease of T suppressor/cytotoxic cell ratio.


Asunto(s)
Antígenos de Carbohidratos Asociados a Tumores/administración & dosificación , Antígenos Virales de Tumores/administración & dosificación , Neoplasias de la Mama/prevención & control , Vacunas/administración & dosificación , Neoplasias de la Mama/inmunología , Neoplasias de la Mama/patología , Femenino , Humanos , Hipersensibilidad Tardía/inmunología , Inyecciones Intradérmicas , Estadificación de Neoplasias , Recurrencia , Estudios Retrospectivos , Tasa de Supervivencia
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