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141.
Carl N. McDaniel Laura K. Hartnett Karla A. Sangrey 《The Plant journal : for cell and molecular biology》1996,9(1):55-61
Employing genotypes of day-neutral tobacco that exhibit a wide range in the number of nodes produced, it has been established that node number, and plant size, in tobacco is regulated, in large part, by two endogenous signals and one developmental state, competence. All genotypes have the same level of a root signal that maintains a vegetative pattern during early growth. The number of nodes produced before the formation of the terminal flower, as well as plant size, is a function of the strength of the floral stimulus from the leaves and the competence of the terminal meristem to respond to the floral stimulus by initiating the terminal flower. 相似文献
142.
Antonio Hernandes Chaves Neto Karla Cristiana Queiroz Renato Milani Edgar Julian Paredes‐Gamero Giselle Zenker Justo Maikel P. Peppelenbosch Carmen Veríssima Ferreira 《Journal of cellular biochemistry》2011,112(1):71-77
Despite numerous reports on the ability of ascorbic acid and β‐glycerophosphate (AA/β‐GP) to induce osteoblast differentiation, little is known about the molecular mechanisms involved in this phenomenon. In this work, we used a peptide array containing specific consensus sequences (potential substrates) for protein kinases and traditional biochemical techniques to examine the signaling pathways modulated during AA/β‐GP‐induced osteoblast differentiation. The kinomic profile obtained after 7 days of treatment with AA/β‐GP identified 18 kinase substrates with significantly enhanced or reduced phosphorylation. Peptide substrates for Akt, PI3K, PKC, BCR, ABL, PRKG1, PAK1, PAK2, ERK1, ERBB2, and SYK showed a considerable reduction in phosphorylation, whereas enhanced phosphorylation was observed in substrates for CHKB, CHKA, PKA, FAK, ATM, PKA, and VEGFR‐1. These findings confirm the potential usefulness of peptide microarrays for identifying kinases known to be involved in bone development in vivo and in vitro and show that this technique can be used to investigate kinases whose function in osteoblastic differentiation is poorly understood. J. Cell. Biochem. 112: 71–77, 2011. © 2010 Wiley‐Liss, Inc. 相似文献
143.
Karla Jean Fullner 《Journal of bacteriology》1998,180(2):430-434
Nonpolar virB mutants of Agrobacterium tumefaciens were tested for RSF1010 mobilization and extracellular complementation. virB2 to virB11 were essential for transfer in both assays. virB1 was essential only for high frequency transfer of RSF1010 and VirE2. Coordinated transfer of a preassembled T complex is supported by these data and competition studies. 相似文献
144.
Elizabeth Ortiz-Gutiérrez Karla García-Cruz Eugenio Azpeitia Aaron Castillo María de la Paz Sánchez Elena R. álvarez-Buylla 《PLoS computational biology》2015,11(9)
Cell cycle control is fundamental in eukaryotic development. Several modeling efforts have been used to integrate the complex network of interacting molecular components involved in cell cycle dynamics. In this paper, we aimed at recovering the regulatory logic upstream of previously known components of cell cycle control, with the aim of understanding the mechanisms underlying the emergence of the cyclic behavior of such components. We focus on Arabidopsis thaliana, but given that many components of cell cycle regulation are conserved among eukaryotes, when experimental data for this system was not available, we considered experimental results from yeast and animal systems. We are proposing a Boolean gene regulatory network (GRN) that converges into only one robust limit cycle attractor that closely resembles the cyclic behavior of the key cell-cycle molecular components and other regulators considered here. We validate the model by comparing our in silico configurations with data from loss- and gain-of-function mutants, where the endocyclic behavior also was recovered. Additionally, we approximate a continuous model and recovered the temporal periodic expression profiles of the cell-cycle molecular components involved, thus suggesting that the single limit cycle attractor recovered with the Boolean model is not an artifact of its discrete and synchronous nature, but rather an emergent consequence of the inherent characteristics of the regulatory logic proposed here. This dynamical model, hence provides a novel theoretical framework to address cell cycle regulation in plants, and it can also be used to propose novel predictions regarding cell cycle regulation in other eukaryotes. 相似文献
145.
Karpe A. V. Dunn M. S. Taylor M. C. Nguyen T. Ong C. Karla T. Rockman S. Beale D. J. 《Metabolomics : Official journal of the Metabolomic Society》2018,14(12):1-1
Metabolomics - The identification of metabolomic dysregulation appears promising for the prediction of type 1 diabetes and may also reveal metabolic pathways leading to beta-cell destruction.... 相似文献
146.
Daniel Brown Leigh Ann Samsa Cade Ito Hong Ma Karla Batres Rima Arnaout Li Qian Jiandong Liu 《Journal of cellular and molecular medicine》2018,22(3):2007-2017
The Neuregulin‐1 (Nrg1)/ErbB pathway plays multiple, critical roles in early cardiac and nervous system development and has been implicated in both heart and nerve repair processes. However, the early embryonic lethality of mouse Nrg1 mutants precludes an analysis of Nrg1's function in later cardiac development and homeostasis. In this study, we generated a novel nrg1 null allele targeting all known isoforms of nrg1 in zebrafish and examined cardiac structural and functional parameters throughout development. We found that zebrafish nrg1 mutants instead survived until young adult stages when they exhibited reduced survivorship. This coincided with structural and functional defects in the developing juvenile and young adult hearts, as demonstrated by reduced intracardiac myocardial density, cardiomyocyte cell number, swimming performance and dysregulated heartbeat. Interestingly, nrg1 mutant hearts were missing long axons on the ventricle surface by standard length (SL) 5 mm, which preceded juvenile and adult cardiac defects. Given that the autonomic nervous system normally exerts fine control of cardiac output through this nerve plexus, these data suggest that Nrg1 may play a critical role in establishing the cardiac nerve plexus such that inadequate innervation leads to deficits in cardiac maturation, function and survival. 相似文献
147.
Karla Berenice Carrazco-Peña Katia Farías-Moreno Benjamín Trujillo-Hernández 《Revista espa?ola de geriatría y gerontología》2018,53(1):23-25
Objective
To determine the frequency of successful aging (SA) and its relationship with frailty in an elderly population.Material and methods
An analytical cross-sectional study of subjects ≥60 years of age seen as outpatients in a general hospital. Successful aging was defined as scores of ≥ 90 in the Barthel index and ≤ 2 in the Pfeiffer test. Frailty was determined using the Fried criteria.Results
The study included 400 subjects (272 women and 128 men), with a mean age of 71.6 ± 8.2 years. The SA frequency was 40.4%. frail status was statistically higher in non-successful aging subjects than in SA subjects (161.7 versus 7.9%; P<.001). Women were more frequently frail, while being a pensioner/retired and married were associated less frequently with frailty.Conclusions
Successful aging is associated with a lower level of frailty. 相似文献148.
149.
Karla Poewe 《American anthropologist》2001,103(3):834-837
Mein Freund Maleboch. Christoph Sonntag. Ulrich van der Heyden. ed. Berlin: Edition Ost, 1999. 256 pp.
Von der philologischen zur volkischen Religionswissenschaft. Horst Junginger. Stuttgart: Franz Steiner Verlag, 1999. 399 pp.
Die Afrikaw issenschaften in der DDR. Ulrich van der Heyden. Miinster. LIT Verlag, 1999. 640 pp. 相似文献
Von der philologischen zur volkischen Religionswissenschaft. Horst Junginger. Stuttgart: Franz Steiner Verlag, 1999. 399 pp.
Die Afrikaw issenschaften in der DDR. Ulrich van der Heyden. Miinster. LIT Verlag, 1999. 640 pp. 相似文献
150.