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981.
Luque-Almagro Víctor M. Cabello Purificación Sáez Lara P. Olaya-Abril Alfonso Moreno-Vivián Conrado Roldán María Dolores 《Applied microbiology and biotechnology》2018,102(3):1067-1074
Applied Microbiology and Biotechnology - Cyanide is one of the most toxic chemicals for living organisms described so far. Its toxicity is mainly based on the high affinity that cyanide presents... 相似文献
982.
983.
Centaurea zlatiborensis (Asteraceae,Cardueae−Centaureinae), a new endemic species from Zlatibor mountain range,Serbia
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Jelica Novaković Bojan Zlatković Maja Lazarević Núria Garcia‐Jacas Alfonso Susanna Petar D. Marin Dmitar Lakušić Pedja Janaćković 《Nordic Journal of Botany》2018,36(6)
A new species of Centaurea sect. Acrocentron (Cass.) DC. (Asteraceae) found growing in dry, steppe‐like habitats on the Zlatibor mountain in western Serbia is described as Centaurea zlatiborensis. This novelity is compared with all other species of C. sect. Acrocentron known from Serbia and a diagnistic key to these is provided. Centaurea zlatiborensis is morphologically close to C. calocephala Willd. but the stems are simple or sparsely branched with monocephalous branches and itis generally smaller in all plant parts. The most important difference is the appendage morphology where C. zlatiborenis has triangular, dark brown appendages with short fimbriae and appendages not completely covering the bracts. 相似文献
984.
Quasi-periodic primary structructures of core proteins of human T-lymphotropic leukemia retroviruses
Alfonso M. Liquori Claudia Sadun Antonio Battisti 《Journal of molecular evolution》1987,26(3):269-273
Summary Fourier analysis, previously introduced by Liquori et al. (1983, 1986), has been applied to the primary structures of two core proteins of human T-lymphotropic leukemia retroviruses HTLV-1 and HTLV-II. The resulting autocorrelation functions display striking patterns that can be interpreted in terms of an approximately fourfold quasi-periodicity of the primary structures.Self-alignments of the amino acid sequences containing a few gaps are consistent with the above finding and suggest that the tertiary structure of these two homologous core proteins contains alpha-helical and delta-helical segments, the latter being characteristic of the threefold helix present in collagen structure.Presented at the FEBS Symposium on Genome Organization and Evolution, held in Crete, Greece, September 1–5, 1986 相似文献
985.
986.
Alfonso Ros Barceló M. Angeles Pedreño Romualdo Muñoz Francisco Sabater 《Physiologia plantarum》1988,73(2):238-244
Extracellular acidic isoperoxidases (EC 1.11.1.7), isolated from both the cell walls and intercellular spaces of lupin ( Lupinus albus L. cv. multolupa) hypocotyls, bound to water-insoluble pectins of wall fragments also isolated from the hypocotyls. The binding was sáturable by increasing the isoenzyme concentration in the assay medium and it was dependent on the pH; neutral pH (6.0–7.0) favoured release, while acidic pH (4.0–5.0) favoured the attachment to the cell wall. Binding of acidic isoperoxidases to wall fractions was correlated with the in vitro acid-induced growth of hypocotyl segments, and both were modulated in the same direction by the Ca2+ /H+ ratio in the incubation media, although the two responses were clearly separated when the Ca2+ /H+ ratio varied. Binding of acidic isoperoxidases of cell walls could operate as a fine control of the activity of these cell wall enzymes, although its physiological role in the cell wall stiffening remains unclear. Some aspects of Ca2+ on the control of peroxidase activity at this level are also discussed. 相似文献
987.
Angelika Hoffmann Johannes Pfeil Julieta Alfonso Felix T. Kurz Felix Sahm Sabine Heiland Hannah Monyer Martin Bendszus Ann-Kristin Mueller Xavier Helluy Mirko Pham 《PLoS pathogens》2016,12(3)
It is poorly understood how progressive brain swelling in experimental cerebral malaria (ECM) evolves in space and over time, and whether mechanisms of inflammation or microvascular sequestration/obstruction dominate the underlying pathophysiology. We therefore monitored in the Plasmodium berghei ANKA-C57BL/6 murine ECM model, disease manifestation and progression clinically, assessed by the Rapid-Murine-Coma-and-Behavioral-Scale (RMCBS), and by high-resolution in vivo MRI, including sensitive assessment of early blood-brain-barrier-disruption (BBBD), brain edema and microvascular pathology. For histological correlation HE and immunohistochemical staining for microglia and neuroblasts were obtained. Our results demonstrate that BBBD and edema initiated in the olfactory bulb (OB) and spread along the rostral-migratory-stream (RMS) to the subventricular zone of the lateral ventricles, the dorsal-migratory-stream (DMS), and finally to the external capsule (EC) and brainstem (BS). Before clinical symptoms (mean RMCBS = 18.5±1) became evident, a slight, non-significant increase of quantitative T2 and ADC values was observed in OB+RMS. With clinical manifestation (mean RMCBS = 14.2±0.4), T2 and ADC values significantly increased along the OB+RMS (p = 0.049/p = 0.01). Severe ECM (mean RMCBS = 5±2.9) was defined by further spread into more posterior and deeper brain structures until reaching the BS (significant T2 elevation in DMS+EC+BS (p = 0.034)). Quantitative automated histological analyses confirmed microglial activation in areas of BBBD and edema. Activated microglia were closely associated with the RMS and neuroblasts within the RMS were severely misaligned with respect to their physiological linear migration pattern. Microvascular pathology and ischemic brain injury occurred only secondarily, after vasogenic edema formation and were both associated less with clinical severity and the temporal course of ECM. Altogether, we identified a distinct spatiotemporal pattern of microglial activation in ECM involving primarily the OB+RMS axis, a distinct pathway utilized by neuroblasts and immune cells. Our data suggest significant crosstalk between these two cell populations to be operative in deeper brain infiltration and further imply that the manifestation and progression of cerebral malaria may depend on brain areas otherwise serving neurogenesis. 相似文献
988.
Orlando Luis de Andrade Santarém Roberto de Cleva Flávia Megumi Sasaya Marianna Siqueira de Assump??o Meive Santos Furtado Alfonso Julio Guedes Barbato Paulo Herman 《PloS one》2016,11(4)
ObjectiveThe aim of this study was to prospectively investigate the long-term cardiovascular and pulmonary hemodynamic effects of surgical shunt for treatment of portal hypertension (PH) due to Schistosomiasis mansoni.LocationThe University of São Paulo Medical School, Brazil; Public Practice.MethodsHemodynamic evaluation was performed with transesophageal Doppler and contrast-enhanced echocardiography (ECHO) on twenty-eight participants with schistosomal portal hypertension. Participants were divided into two groups according to the surgical procedure used to treat their schistosomal portal hypertension within the last two years: group 1—distal splenorenal shunt (DSRS, n = 13) and group 2—esophagogastric devascularization and splenectomy (EGDS, n = 15).ResultsThe cardiac output (5.08 ± 0.91 L/min) and systolic volume (60.1 ± 5.6 ml) were increased (p = 0.001) in the DSRS group. DSRS participants had a significant increase (p < 0.0001) in their left ventricular end-systolic and end-diastolic diameters as well as in their left ventricular end-diastolic and end-systolic volumes (p < 0.001) compared with the preoperative period. No statistically significant difference was found in the patients who underwent EGDS. ECHO revealed intrapulmonary vasodilatation (IPV) in 18 participants (64%), 9 DSRS and 9 EGDS (p > 0.05).ConclusionsThe late increase in the cardiac output, stroke volume and left ventricular diameters demonstrated left ventricular dilatation after a distal splenorenal shunt. ECHO revealed a greater prevalence for IPV in patients with schistosomiasis than has previously been described in patients with PH from liver cirrhosis. 相似文献
989.
990.
Oliver Preyer Dorthe Johansen Jessica Holly Tanja Stocks Alfonso Pompella Gabriele Nagel Hans Concin Hanno Ulmer Nicole Concin 《PloS one》2016,11(2)