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536
Formation of pluripotent stem cells in the mammalian embryo depends on the POU transcription factor Oct4
- Cell
, 1998
"... cell types, including germ cells. The ICM and its succes-sor the epiblast are highly regulative stem cell popula-tions that can adjust to various perturbations including major alterations in cell number and cell position (Hogan et al., 1994). The pool of stem cells remains pluripotent ..."
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Cited by 279 (14 self)
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cell types, including germ cells. The ICM and its succes-sor the epiblast are highly regulative stem cell popula-tions that can adjust to various perturbations including major alterations in cell number and cell position (Hogan et al., 1994). The pool of stem cells remains pluripotent
Optimal Birth Control of Population Dynamics. II. Problems with Free Final Time, Phase Constraints, and Mini-Max Costs*
, 1988
"... We study optimal birth control of population systems of McKendrick type which is a distributed parameter system involving first order partial differential equations with nonlocal bilinear boundary control. New results on problems with free final time, phase constraints, and mini-max costs are presen ..."
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Cited by 1 (0 self)
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problem is a special case (but relaxing many convexity assumptions). Systems with phase constraints are also studied. Finally, mini-max control for popula-tion regulation is characterized. It is assumed that the reader is familiar with the terminology and notation of [ 11. 5. FREE FINAL TIME PROBLEM
AN EPIDEMIOLOGICAL SURVEY ON THE PREVALENCE
"... Abstract The aim of the study was to evaluate the prevalence of Salmonella spp. in swine herds in Italy. Samples of faeces from finishing swine farms, cecal contents and ileo-cecal lymphnodes from pigs at slaughter were analysed for Salmonella. Samples of blood serum and meat juice were collected fr ..."
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, sulfonamides, streptomycin and ampicillin. Introduction The recent European Regulation, regarding the control of zoonosis in animal popula-tions (Regulation CE 2160/2003 and Directive 2003/99), will require, in the next years, the imple-mentation of monitoring programs for Salmonella in swine. From
Self-determination and persistence in a real-life setting: Toward a motivational model of high school dropout.
- Journal of Personality and Social Psychology,
, 1997
"... The purpose of this study was to propose and test a motivational model of high school dropout. The model posits that teachers, parents, and the school administration's behaviors toward students influence students' perceptions of competence and autonomy. The less autonomy supportive the so ..."
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Cited by 183 (19 self)
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, especially as pertains to their antecedents and consequences. Finally, such a model, if proven valid, should provide a better understanding of the process involved in dropping out of high school, thereby leading to potential insights concerning future interventions with this population. Below, we present
POPULATION ECOLOGY
"... Abstract Density dependence plays a key role in life-history characteristics and population ecology of large, herbivorous mammals. We designed a manipulative experiment to test hypotheses relating effects of density-dependent mechanisms on physical condition and fecundity of North American elk (Cerv ..."
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on the role of spring and summer nutrition on popula-tion regulation in large, northern herbivores.
Population Fluctuations in Urceolaria mitra (Peritricha) and Enchytraeus albidus (Oligochaeta) and their Bearing on Regulation
"... Publication within the same year of two di-vergent views on the regulation of animal popula-tions (Nicholson, 1954; Andrewartha nd Birch, 1954) has re-focussed the scrutiny of ecologists ..."
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Publication within the same year of two di-vergent views on the regulation of animal popula-tions (Nicholson, 1954; Andrewartha nd Birch, 1954) has re-focussed the scrutiny of ecologists
Regulating gene drives
"... Regulatory gaps must be filled before gene drives could be used in the wild cannot be used to engineer populations of viruses or bacteria. Second, a newly released drive will typically take dozens of genera-tions to affect a substantial proportion of a target population, unless drive-containing orga ..."
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-containing organisms are released in numbers consti-tuting a substantial fraction of the popula-tion. The process may require only a year or less for some invertebrates, but centuries for organisms with long generation times. Studies have evaluated the possibility of releasing transgenic mosquitoes to combat
Thy-1 expression regulates the ability of rat lung fibroblasts to activate transforming growth factor-beta in response to fibrogenic stimuli
- Am. J. Pathol
, 2004
"... Distinct subpopulations of fibroblasts contribute to lung fibrosis, although the mechanisms underlying fibrogenesis in these subpopulations are not clear. Differential expression of the glycophosphatidyli-nositol-linked protein Thy-1 affects proliferation and myofibroblast differentiation. Lung fibr ..."
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Cited by 8 (1 self)
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fibroblast popula-tions selected on the basis of Thy-1 expression by cell sorting were examined for responses to fibrogenic stimuli. Thy-1 () and Thy-1 () fibroblast popula-tions were treated with platelet-derived growth factor-BB, interleukin-1 , interleukin-4, or bleomycin and assessed for activation
Gradients in density variations of small rodents – the importance of latitude and snow cover
- Oecologia
, 1985
"... Summary. Microtine rodents are known to show extreme population variations (cycles) but non-cyclic populations have also been recognized uring recent years. The cyclic populations have been widely thought o be regulated by intrinsic mechanisms. However, such predictions for cyclic populations are us ..."
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Cited by 69 (1 self)
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Summary. Microtine rodents are known to show extreme population variations (cycles) but non-cyclic populations have also been recognized uring recent years. The cyclic populations have been widely thought o be regulated by intrinsic mechanisms. However, such predictions for cyclic populations
A molecular link between stem cell regulation and floral patterning in Arabidopsis
- Cell
, 2001
"... The homeotic gene AGAMOUS (AG) has dual roles in specifying organ fate and limiting stem cell prolifera-tion in Arabidopsis flowers. We show that the floral identity protein LEAFY (LFY), a transcription factor ex-pressed throughout the flower, cooperates with the homeodomain protein WUSCHEL (WUS) to ..."
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Cited by 42 (1 self)
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) to activate AG in the center of flowers. WUS was previously identified because of its role in maintaining stem cell populations in both shoot and floral meristems. The unsuspected additional role of WUS in regulating floral homeotic gene expression supports the hypothesis that floral patterning uses a general
Results 1 - 10
of
536
