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951.
952.
Marlies Vaz Nunes 《Journal of theoretical biology》1981,92(3):227-239
A graphical method is presented which allows the prediction of phase resetting curves of circadian rhythms for both type 1 and type 0 resetting, starting from one experimentally determined phase resetting curve. Calculations were based on literature data for the pupal eclosion rhythm of Drosophila pseudoobscura. The method is based on the assumption that for all practical purposes the rhythm may be approached as a “simple clock”, i.e. an oscillator with only one state variable, namely its phase or circadian time, CT. Besides predicting both “types” of phase resetting the method is capable to locate the “position” of the phase singularity and thus the transition from type 1 to type 0 resetting. This graphical method is an elaboration of the “transformation method”, developed in 1972 by A. Johnsson and H. G. Karlsson, which was effective in predicting phase resetting by “strong” stimuli, but failed in the case of “weak” stimuli. Predictions made using the extended transformation method are in good agreement with experimental results obtained with Drosophila. Also for the flesh fly, Sarcophaga argyrostoma, a prediction is made of the position of the phase singularity of the eclosion rhythm and compared with experimental results. 相似文献
953.
White William T. Vaz Diego F. B. Ho Hsuan-Ching Ebert David A. de Carvalho Marcelo R. Corrigan Shannon Rochel Elisabeth de Carvalho Murilo Tanaka Sho Naylor Gavin J. P. 《Ichthyological Research》2015,62(2):213-229
Ichthyological Research - The somniosid species Scymnodon ichiharai Yano and Tanaka 1984 is redescribed based on the type specimens and additional material from Taiwan and Japan. The range of this... 相似文献
954.
Aline B.M. Vaz Andre G.F.C. da Costa Lucélia V.V. Raad Aristóteles Góes-Neto 《Fungal biology》2014,118(3):277-286
Fungal endophytes associated with Myrtaceae from Brazil and Argentina were isolated at three levels of nesting: leaf, individual host trees, and site collection. The alternating logistic regression (ALR) was used to model the data because it offers a computationally convenient method for fitting regression structures involving large clusters. The objectives of this study were to determine: (i) whether the colonization pattern is influenced by environmental variables, (ii) if there is some leaf part they prefer to colonize; (iii) if there is some fungal endophyte aggregation between hierarchical levels; (iv) what the distance effect is on the fungal association. The environmental variables were statistically significant only for Xylaria, i.e., when the elevation and water precipitation increase and the temperature decreases, the odds ratio of finding another fungal endophyte of that genus previously found increases. Sordariomycetes, Xylariales, and Xylaria exhibited leaf fragment preference to petiole and tip. Fungal endophytes showed association within leaf. The horizontal transmission mode and the dispersal limitation may explain this association at the leaf level. Moreover, our results suggest that when a fungal endophyte infects a leaf or host tree individual, the odds ratio of dispersal inside them is greater. 相似文献
955.
Release of immunoreactive-neuropeptide by rat platelets 总被引:4,自引:0,他引:4
A K Myers M Y Farhat C A Vaz H R Keiser Z Zukowska-Grojec 《Biochemical and biophysical research communications》1988,155(1):118-122
Neuropeptide Y, a potent vasoconstrictor and cardiac depressant, is re-leased from sympathetic nerve endings. Its presence in megakaryocytes suggests this peptide might be stored in platelet granules and released during aggregation. Immunoreactive-neuropeptide Y was measured in platelet rich and platelet poor plasma, and was substantially greater in the former. Addition of collagen to platelets resulted in release of neuropeptide Y which paralleled, in a concentration-dependent manner, the degree of platelet aggregation. Adenosine diphosphate, at concentrations which induce only the first phase of aggregation and not the release reaction, caused only a minor release of neuropeptide Y. These results suggest that platelet release could be a major source of circulating neuropeptide Y and could contribute to hemodynamics of pathophysiological states involving platelet activation. 相似文献
956.
957.
Edmarcia Elisa de Souza Heidi Hehnly Arina Marina Perez Gabriela Vaz Meirelles Juliana Helena Costa Smetana Stephen Doxsey J?rg Kobarg 《Cell cycle (Georgetown, Tex.)》2015,14(4):656-667
The mitotic spindle apparatus is composed of microtubule (MT) networks attached to
kinetochores organized from 2 centrosomes (a.k.a. spindle poles). In addition to this
central spindle apparatus, astral MTs assemble at the mitotic spindle pole and attach to
the cell cortex to ensure appropriate spindle orientation. We propose that cell
cycle-related kinase, Nek7, and its novel interacting protein RGS2, are involved in
mitosis regulation and spindle formation. We found that RGS2 localizes to the mitotic
spindle in a Nek7-dependent manner, and along with Nek7 contributes to spindle morphology
and mitotic spindle pole integrity. RGS2-depletion leads to a mitotic-delay and severe
defects in the chromosomes alignment and congression. Importantly, RGS2 or Nek7 depletion
or even overexpression of wild-type or kinase-dead Nek7, reduced γ-tubulin from the
mitotic spindle poles. In addition to causing a mitotic delay, RGS2 depletion induced
mitotic spindle misorientation coinciding with astral MT-reduction. We propose that these
phenotypes directly contribute to a failure in mitotic spindle alignment to the
substratum. In conclusion, we suggest a molecular mechanism whereupon Nek7 and RGS2 may
act cooperatively to ensure proper mitotic spindle organization. 相似文献
958.
959.
The purpose of this review was to build upon a recent review by Weigelt et al. which examined visual search strategies and face identification between individuals with autism spectrum disorders (ASD) and typically developing peers. Seven databases, CINAHL Plus, EMBASE, ERIC, Medline, Proquest, PsychInfo and PubMed were used to locate published scientific studies matching our inclusion criteria. A total of 28 articles not included in Weigelt et al. met criteria for inclusion into this systematic review. Of these 28 studies, 16 were available and met criteria at the time of the previous review, but were mistakenly excluded; and twelve were recently published. Weigelt et al. found quantitative, but not qualitative, differences in face identification in individuals with ASD. In contrast, the current systematic review found both qualitative and quantitative differences in face identification between individuals with and without ASD. There is a large inconsistency in findings across the eye tracking and neurobiological studies reviewed. Recommendations for future research in face recognition in ASD were discussed. 相似文献
960.
Luís M. B. B. Estronca Hugo A. L. Filipe Armindo Salvador Maria Jo?o Moreno Winchil L. C. Vaz 《Journal of lipid research》2014,55(6):1033-1043
The rate of noncatalyzed transfer of cholesterol (Chol) among lipoproteins and cells in the blood is of fundamental importance as a baseline to assess the role of active transport mechanisms, but remains unknown. Here we address this gap by characterizing the association of the Chol analog, ergosta-5,7,9(11),22-tetraen-3β-ol (DHE), with the lipoproteins VLDL, LDL, HDL2, and HDL3. Combining these results with data for the association of DHE with liposomes, we elaborated a kinetic model for the noncatalyzed exchange of free Chol among blood compartments. The computational results are in good agreement with experimental values. The small deviations are explained by the nonequilibrium distribution of unesterified Chol in vivo, due to esterification and entry of new unesterified Chol, and eventual effects introduced by incubations at low temperatures. The kinetic profile of the homeostasis of unesterified Chol in the blood predicted by the model developed in this work is in good agreement with the observations in vivo, highlighting the importance of passive processes. 相似文献