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1.
It has long been debated whether the mind consists of specialized and independently evolving modules, or whether and to what extent a general factor accounts for the variance in performance across different cognitive domains. In this study, we used a hierarchical Bayesian model to re-analyse individual level data collected on seven primate species (chimpanzees, bonobos, orangutans, gorillas, spider monkeys, brown capuchin monkeys and long-tailed macaques) across 17 tasks within four domains (inhibition, memory, transposition and support). Our modelling approach evidenced the existence of both a domain-specific factor and a species factor, each accounting for the same amount (17%) of the observed variance. In contrast, inter-individual differences played a minimal role. These results support the hypothesis that the mind of primates is (at least partially) modular, with domain-specific cognitive skills undergoing different evolutionary pressures in different species in response to specific ecological and social demands. 相似文献
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F. Rollo A. La Marca A. Amici 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1987,73(4):501-505
Summary Twelve seed specimens of varying ages and from different archaeological sites were analyzed for the presence of polymerized DNA and RNA. Amongst the samples tested, one of Vitis vinifera from an archaeological site in Iran (2,000–3,000 B.C.) was found to be completely devoid of nucleic acids. Zea mais seeds of Precolumbial age from Peru (about 800 A.D.) contained depolymerized DNA and RNA. Samples of Vitis vinifera and Rubus sp. from a Lombard archaeological site (800 A.D.) as well as radiocarbon dated seeds from the site of the Spring Sanctuary near Metaponto (I–IV century B.C.) were found to contain polymerized DNA and rRNA bands. However the electrophoretic properties of the rRNAs in one case and hybridization experiments performed with cloned seed DNA in the other, clearly demonstrated that the polymerized nucleic acids were not of plant origin. 相似文献
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E Perez G Zamboni R Amici L Fadiga M Calasso P L Parmeggiani 《Bollettino della Società italiana di biologia sperimentale》1989,65(1):41-45
In control conditions preoptic cAMP concentration during wakefulness was significantly higher than during synchronized sleep. No differences in nucleotide concentration were observed in the cerebral cortex. Propranolol decreases brain cAMP concentration. This change was associated with the suppression of the difference observed between wakefulness and synchronized sleep in the preoptic region. 相似文献
7.
Roberta Colombo Raffaella Cerana Piera Lado Antonio Peres 《The Journal of membrane biology》1988,103(3):227-236
Summary The patch-clamp technique in whole-cell configuration was used to study the electrical properties of the tonoplast in isolated vacuoles fromAcer pseudoplatanus cultured cells. In symmetrical KCl or K2 malate solutions, voltage- and time-dependent inward currents were elicited by hyperpolarizing the tonoplast (inside negative), while in the positive range of potential the conductance was very small. The specific conductance of the tonoplast at –100 mV, in 100mm symmetrical KCl was about 160 S/cm2. The reversal potentials (E
rev) of the current, measured in symmetrical or asymmetrical ion concentrations (cation, anion or both) were very close to the values of the K+ equilibrium potential. Experiments performed in symmetrical or asymmetrical NaCl indicate that Na+ too can flow through the channels. NeitherE
rev nor amplitude and kinetics of the current changed by replacing NaCl with KCl in the external solution. These results indicate the presence of hyperpolarization-activated channels in tonoplasts, which are permeable to K+ as well as to Na+. Anions such as Cl– or malate seem to contribute little to the channel current. 相似文献
8.
Anna Maria Greco Pasquale Gambardella Raffaella Sticchi Diego D'aponte Pietro De Franciscis 《Chronobiology international》1988,5(3):217-225
Circadian rhythms of serotonin (5HT), its precursors tryptophan (TP) and 5-hydroxy-tryptophan (5HTP) and its acid catabolite 5-hydroxy-indoleacetic acid (5HIAA), were determined in the hypothalamus of control rats and rats which had been treated continuously with subcutaneous imipramine (10 mg/kg/day) for 2 weeks.
Rats were individually housed and entrained to LD12:12. Controls showed the 5HT and TP peaks in the light and dark periods respectively, as reported in the literature, but no inverted correlation (antiphase) between SHT and 5HIAA rhythms.
Imipramine significantly modified circadian rhythm characteristics: the 5HT acrophase was advanced, that of TP and 5HIAA was delayed. Imipramine also significantly increased hypothalamic SHT and TP concentrations. 相似文献
Rats were individually housed and entrained to LD12:12. Controls showed the 5HT and TP peaks in the light and dark periods respectively, as reported in the literature, but no inverted correlation (antiphase) between SHT and 5HIAA rhythms.
Imipramine significantly modified circadian rhythm characteristics: the 5HT acrophase was advanced, that of TP and 5HIAA was delayed. Imipramine also significantly increased hypothalamic SHT and TP concentrations. 相似文献
9.
The metabolism of glucose 1-phosphate and glucose 6-phosphate and their influence on the metabolism of glucose in rat-diaphragm muscle 总被引:6,自引:4,他引:2
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10.
Raffaella Scardigli Silvia Soddu Rita Falcioni Marco Crescenzi Letizia Cimino Ada Sacchi 《Experimental cell research》1996,227(2):223
Integrin β4subunit is present in association with α6chain on both normal and transformed epithelial cells. Recently α6β4heterodimer was found on the endothelium of medium-sized blood vessels and on immature thymocytes. In this report we show, by Northern blotting, indirect immunofluorescence, immunoprecipitation, and Western blotting, that β4subunit is expressed also on cells of mesenchymal origin such as fibroblasts, myoblasts, and myotubes. Increased expression of α6β4has been related to the aggressive metastatic phenotype of human and murine carcinomas. The transforming growth factor β1(TGF-β1) has been found to modulate the expression of several integrins and intracellular matrix proteins, as well as to stimulate cell invasion and metastatic potential. To evaluate whether α6β4expression is modulated by TGF-β1, we transfected 3T3 fibroblasts with an expression vector carrying the human TGF-β1cDNA driven by the SV40 early promoter. We observed by indirect immunofluorescence a modification in the subcellular distribution of β4subunit, which acquires a perinuclear localization. This finding suggests this integrin subunit correlates with the cytoskeletal reorganization induced by TGF-β1. 相似文献