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991.
Carmen González-Lluch Joaquín L. Sancho-Bru Pablo-Jesús Rodríguez-Cervantes 《Computer methods in biomechanics and biomedical engineering》2014,17(10):1108-1118
Many studies have investigated the effect of different parameters of the endodontically restored tooth on its final strength, using in vitro tests and model simulations. However, the differences in the experimental set-up or modelling conditions and the limited number of parameters studied in each case prevent us from obtaining clear conclusions about the relative importance of each parameter. In this study, a validated 3D biomechanical model of the restored tooth was used for an exhaustive sensitivity analysis. The individual influence of 20 different parameters on the mechanical performance of an endodontic restoration with prefabricated posts was studied. The results bring up the remarkable importance of the loading angle on the final restoration strength. Flexural loads are more critical than compressive or tensile loads. Young's modulus of the post and its length and diameter are the most influential parameters for strength, whereas other parameters such as ferrule geometry or core and crown characteristics are less significant. 相似文献
992.
Flavio Flamigni Gabriele Campana Lucia Carboni Carmen Rossoni Santi Spampinato 《Biochimica et Biophysica Acta (BBA)/General Subjects》1994,1201(1):101-105
Addition of Zn2+_ to cell medium inhibited the induction of ornithine decarboxylase (ODC) activity in ODC overproducing L1210-DFMOr cells. A significant effect was observed at a concentration as low as 0.01 mM, however a more marked inhibition was caused by the addition of 0.1 mM Zn2+. The inhibition of the induction of ODC activity was accompanied by a proportional decrease in the content of immunoreactive ODC protein, whereas the level of ODC mRNA, detemined by a solution hybridization RNase protection assay, was not affected signigicantly. Instead, some acceleration of ODC turnover was observed. the addition of 0.1 mM Co2+ or Mn2+, but not of other divalent metal ions, also inhibited ODC induction; differently from Zn2+ however, these metals affected cell viability and/or cell growth. Removal of endogenous Zn2+ by a chelator also provoked a strong decrease of ODC induction, which was reversed by Zn2+. However, addition of Zn2+ in excess of the chelator proved to be markedly inhibitory. These results indicate that both a restricted Zn2+ availability and an enhanced presence of the metal can inhibit the induction of ODC in L1210-DFMOr cells. 相似文献
993.
Francesca Pennacchietti Stefania Abbruzzetti Aba Losi Carmen Mandalari Roberta Bedotti Cristiano Viappiani Francesca Cella Zanacchi Alberto Diaspro Wolfgang G?rtner 《PloS one》2014,9(9)
We report thermal recovery kinetics of the lit state into the parental dark state, measured for the blue light-sensing photoreceptor YtvA inside overexpressing E. coli and B. subtilis bacterial cells, performed for the wild type and several mutated proteins. Recovery was followed as a recovery of the fluorescence, as this property is only found for the parental but not for the photochemically generated lit state. When cells were deposited onto a microscope glass plate, the observed thermal recovery rate in the photocycle was found ca. ten times faster in comparison to purified YtvA in solution. When the E. coli or B. subtilis colonies were soaked in an isotonic buffer, the dark relaxation became again much slower and was very similar to that observed for YtvA in solution. The observed effects show that rate constants can be tuned by the cellular environment through factors such as hydration. 相似文献
994.
María A. Ruvira Teresa LucenaMaría J. Pujalte David R. ArahalM. Carmen Macián 《Systematic and applied microbiology》2013
A facultatively anaerobe, moderately halophilic, Gram-negative, filamentous, non motile and unpigmented bacterium, designated M30T, was isolated from coastal Mediterranean Sea water in Valencia, Spain. Phylogenetic analysis based on 16S rRNA sequences placed this strain in the phylum “Bacteroidetes” with Marinifilum fragile JC2469T as its closest relative with 97% sequence similarity. Average nucleotide identity (ANI) values between both strains were far below the 95% threshold value for species delineation (about 89% using BLAST and about 90% using MUMmer). A comprehensive polyphasic study, including morphological, biochemical, physiological, chemotaxonomic and phylogenetic data, confirmed the independent species status of strain M30T within the genus Marinifilum, for which the name Marinifilum flexuosum sp. nov. is proposed. The type strain of Marinifilum flexuosum is M30T (=CECT 7448T = DSM 21950T). 相似文献
995.
996.
Loreta M. Medina Carmen Maria Trujillo Carmen Diaz Argelia Martin Luis Puelles 《Journal of morphology》1990,205(1):113-121
In a Golgi study of the area triangularis (AT), a rostral nucleus of the ventral thalamus of Gallotia galloti, we have identified four major neuronal types on the basis of their morphological characteristics: medium-sized fusiforms with two processes, medium-sized fusiforms with three or four processes, small bipolars, and small and medium-sized multipolars. These neurons are characterized by a simple morphology and radial arrangement. Cell size varies from small to medium, and all axons project laterally. These characteristics distinguish AT neurons from those of neighboring nuclei. In addition, we found some evidence of differential topographic distribution of each neuronal type within the nucleus. Medium-sized fusiform neurons with two processes are located in the most ventral part, where they constitute the ventral nuclear limit. Small multipolar neurons prevail in the dorsal and ventromedial parts, and in the rest of the nucleus medium-sized neurons, including both fusiform with three or four processes and multipolar types, are normally found. Finally, we discuss a putative homology of the reptilian AT with a part of the mammalian zona incerta. 相似文献
997.
Glycine accomplishes several functions as a transmitter in the central nervous system(CNS). As an inhibitory neurotransmitter, it participates in the processing of motor and sensory information that permits movement, vision, and audition. This action of glycine is mediated by the strychnine-sensitive glycine receptor, whose activation produces inhibitory post-synaptic potentials. In some areas of the CNS, glycine seems to be co-released with GABA, the main inhibitory amino acid neurotransmitter. In addition, glycine modulates excitatory neurotransmission by potentiating the action of glutamate at N-methyl-D-aspartate (NMDA) receptors. It is believed that the termination of the different synaptic actions of glycine is produced by rapid reuptake through two sodium-and-chloride-coupled transporters, GLYT1 and GLYT2, located in the plasma membrane of glial cells or pre-synaptic terminals, respectively. Glycine transporters may become major targets for therapeutic of pathological alterations in synaptic function. This article reviews recent progress on the study of the molecular heterogeneity, localization, function, structure, regulation and pharmacology of the glycine transporter 相似文献
998.
Francisco José González Minero Isabel Iglesias Victoria Jato Maria Jesús Aira Pilar Candau Julia Morales Carmen Tomas 《Aerobiologia》1998,14(2-3):117-129
A comparative study is presented of the pollen emissions of Urticaceae, Plantaginaceae and Poaceae, collected during 1995
with Hirst samplers (Burkard or Lanzoni) at five sites in western Spain: two Mediterranean sites located in the south (Huelva
and Seville) and three Atlantic sites in the north (Orense, Vigo and Santiago). The annual pollen of Poaceae and Plantaginaceae
collected in the Atlantic cities was found to be twice that in the Mediterranean sites, and the total amount of Urticaceae
was higher at sites with an urban environment and subject to sea influence (Vigo, Huelva and Seville). At all the sites, the
start of the main pollination periods (MPP) took place in the following order: Urticaceae, Plantaginaceae and Poaceae. It
was also observed that the MPP of these three pollen types began earlier in Huelva and Seville, where the mean temperatures
necessary for the beginning of pollen emissions are recorded very early. Regarding the variation in pollen concentrations
throughout the year, Urticaceae presented peaks of maximum concentration in March (Huelva, Seville, Vigo and Orense) and June
(Santiago); Plantaginaceae in March (south) and June (north); and Poaceae in May (south) and June–July (north). At northern
sites, pollen emissions of Urticaceae and Plantaginaceae continued throughout the summer, while in the south they decreased
considerably from May onwards. From the allergenic point of view, the indices of reactivity described for Urticaceae and Poaceae
were exceeded more often at northern sites, in particular at Vigo. The meteorological conditions associated with periods of
highest pollen emission of these three herbaceous types are a rise in mean temperature, light or absent rainfall, and abundant
sunshine. The statistical correlations between pollen emissions and meteorological factors were not well-defined, either for
the stations or for all the taxa, although they were clearer for the Atlantic cities and for Urticaceae. 相似文献
999.
1000.
Fernando Diez Marcela Cornelis JosÉ Luis Pall MarÍa Del Carmen CoscarÓn 《分类学与生物多样性》2018,16(6):565-575
The first step to understanding the species present in a particular area is to perform inventory and assemblage studies. To obtain a species inventory, it is important to determine parameters such as species richness and relative abundance. This information can be useful for future studies and decision-making purposes in the conservation area. Despite the fundamental role of the terrestrial Heteroptera in ecosystems, they remain poorly known. We expected that the terrestrial Heteroptera species assemblage would be strongly associated with plant communities. Presently, 840 samples were collected in northern Argentine Patagonia during two years, 2013 and 2014. A total of 1950 adults of terrestrial Heteroptera belonging to 12 families, 32 species, and 8 morphospecies were found. Various statistical techniques were applied to correct the observed data for undersampling bias. These suggested that the lower boundary of the summer Heteroptera species richness in northern Patagonia was about 44–54 species. We concluded that the high regional habitat heterogeneity along the west-to-east and south-to-north gradients was paralleled by the turnover of Heteroptera. However, the Patagonian steppe shared a high number of species with the Monte and Subantarctic provinces. The suction sampling technique is an efficient technique to collect Heteroptera in environments with different plant structure and should thus be used in a complementary way with the sweeping technique. 相似文献