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71.
Dominik P. J. Heib Kerstin Hoedlmoser Peter Anderer Josef Zeitlhofer Georg Gruber Wolfgang Klimesch Manuel Schabus 《PloS one》2013,8(12)
There is growing evidence of the active involvement of sleep in memory consolidation. Besides hippocampal sharp wave-ripple complexes and sleep spindles, slow oscillations appear to play a key role in the process of sleep-associated memory consolidation. Furthermore, slow oscillation amplitude and spectral power increase during the night after learning declarative and procedural memory tasks. However, it is unresolved whether learning-induced changes specifically alter characteristics of individual slow oscillations, such as the slow oscillation up-state length and amplitude, which are believed to be important for neuronal replay. 24 subjects (12 men) aged between 20 and 30 years participated in a randomized, within-subject, multicenter study. Subjects slept on three occasions for a whole night in the sleep laboratory with full polysomnography. Whereas the first night only served for adaptation purposes, the two remaining nights were preceded by a declarative word-pair task or by a non-learning control task. Slow oscillations were detected in non-rapid eye movement sleep over electrode Fz. Results indicate positive correlations between the length of the up-state as well as the amplitude of both slow oscillation phases and changes in memory performance from pre to post sleep. We speculate that the prolonged slow oscillation up-state length might extend the timeframe for the transfer of initial hippocampal to long-term cortical memory representations, whereas the increase in slow oscillation amplitudes possibly reflects changes in the net synaptic strength of cortical networks. 相似文献
72.
Pauline Scherdel Jean-Fran?ois Salaün Marie-No?lle Robberecht-Riquet Laura Reali Gabriella Páll Elke J?ger-Roman Manuel Praena Crespo Marilena Moretto Margareta Seher-Zupan?i? Sigurlaug Agustsson the European Confederation of Primary Care Paediatricians research group Martin Chalumeau 《PloS one》2013,8(8)
Objective
We aimed to study current practices in growth monitoring by European primary care paediatricians and to explore their perceived needs in this field.Methods
We developed a cross-sectional, anonymous on-line survey and contacted primary care paediatricians listed in national directories in the 18 European countries with a confederation of primary care paediatricians. Paediatricians participated in the survey between April and September 2011.Results
Of the 1,198 paediatricians from 11 European countries (response rate 13%) who participated, 29% used the 2006 World Health Organization Multicentre Growth Reference Study growth charts, 69% used national growth charts; 61% used software to draw growth charts and 79% did not use a formal algorithm to detect abnormal growth on growth charts. Among the 21% of paediatricians who used algorithms, many used non-algorithmic simple thresholds for height and weight and none used the algorithms published in the international literature. In all, 69% of paediatricians declared that a validated algorithm to monitor growth would be useful in daily practice. We found important between-country variations.Conclusion
The varied growth-monitoring practices declared by primary care paediatricians reveals the need for standardization and evidence-based algorithms to define abnormal growth and the development of software that would use such algorithms. 相似文献73.
Nogueira-Ferreira Rita Ferreira Rita Padrão Ana Isabel Oliveira Paula Santos Manuel Kavazis Andreas N. Vitorino Rui Moreira-Gonçalves Daniel 《Journal of physiology and biochemistry》2019,75(4):561-572
Journal of Physiology and Biochemistry - Aerobic exercise training induces a unique cardioprotective phenotype, but it is becoming clear that it does not promote the same structural, functional,... 相似文献
74.
Vázquez-Fernández MÁ Bermejo MR Fernández-García MI González-Riopedre G Rodríguez-Doutón MJ Maneiro M 《Journal of inorganic biochemistry》2011,105(12):1538-1547
The peroxidase and catalase activities of eighteen manganese-Schiff base complexes have been studied. A correlation between the structure of the complexes and their catalytic activity is discussed on the basis of the variety of systems studied. Complexes 1-18 have the general formulae [MnLn(D)2](X)(H2O/CH3OH)m, where Ln = L1-L13; D = H2O, CH3OH or Cl; m = 0-2.5 and X = NO3−, Cl−, ClO4−, CH3COO−, C2H5COO− or C5H11COO−. The dianionic tetradentate Schiff base ligands H2Ln are the result of the condensation of different substituted (OMe-, OEt-, Br-, Cl-) hydroxybenzaldehyde with diverse diamines (1,2-diaminoethane for H2L1-H2L2; 1,2-diamino-2-methylethane for H2L3-H2L4; 1,2-diamino-2,2-dimethylethane for H2L5; 1,2-diphenylenediamine for H2L6-H2L7; 1,3-diaminopropane for H2L8-H2L11; 1,3-diamino-2,2-dimethylpropane for H2L12-H2L13). The new Mn(III) complexes [MnL1(H2O)Cl](H2O)2.5 (2), [MnL2(H2O)2](NO3)(H2O) (4), [MnL6(H2O)2][MnL6(CH3OH)(H2O)](NO3)2(CH3OH) (8), [MnL6(H2O)(OAc)](H2O) (9) and [MnL7(H2O)2](NO3)(CH3OH)2 (12) were isolated and characterised by elemental analysis, magnetic susceptibility and conductivity measurements, redox studies, ESI spectrometry and UV, IR, paramagnetic 1H NMR, and EPR spectroscopies. X-ray crystallographic studies of these complexes and of the ligand H2L6 are also reported. The crystal structures of the rest of the complexes have been previously published and herein we have only revised their study by those techniques still not reported (EPR and 1H NMR for some of these compounds) and which help to establish their structures in solution. Complexes 1-12 behave as more efficient mimics of peroxidase or catalase in contrast with 13-18. The analysis between the catalytic activity and the structure of the compounds emphasises the significance of the existence of a vacant or a labile position in the coordination sphere of the catalyst. 相似文献
75.
Echevarría-Machado I Martínez-Estévez M Muñoz-Sánchez JA Loyola-Vargas VM Hernández-Sotomayor SM De Los Santos-Briones C 《Molecular biotechnology》2007,35(3):297-309
We have previously reported that Catharanthus roseus transformed roots contain at least two phosphatidylinositol 4,5-bisphosphate-phospholipase C (PLC) activities, one soluble
and the other membrane associated. Detergent, divalent cations, and neomycin differentially regulate these activities and
pure protein is required for a greater understanding of the function and regulation of this enzyme. In this article we report
a partia purification of membrane-associated PLC. We found that there are at least two forms of membrane-associated PLC in
transformed roots of C. roseus. These forms were separated on the basis of their affinity for heparin. One form shows an affinity for heparin and elutes
at approx 600 mM KCl. This form has a molecular mass of 67 kDa by size exclusion chromatography and Western blot analysis, whereas the other
form does not bind to heparin and has a molecular mass of 57 kDa. Possible differential regulation of these forms during transformed
root growth is discussed. 相似文献
76.
The mating call of Isoperla bipartita is described. The male call is composed of 3–10 groups, each of 1–4 rubs. The times between rubs average 89.52 msec (between first and second), 43.52 msec (between second and third) and 35.28 msec (between third and fourth). The time between two groups averages 180.75 msec and varies from 142 to 290 msec. The female answer is composed of a beat and rub repeated at 479.09 msec intervals on average and interspersed between the male call groups between 94 and 184 msec (mean = 118.11 msec) after the last rub of the male group. The I. bipartita call can be considered as a ‘complex and modified pattern’ because the male produces calls of 1–4 rubs by group and the female answers overlapping the male call by percussion-rubbing-produced signals. Moreover, it is different from other studied Iberian Isoperla calls, being probably a species-specific behavioural pattern. 相似文献
77.
Roselló-Lletí E Rivera M Cortés R Azorín I Sirera R Martínez-Dolz L Hove L Cinca J Lago F González-Juanatey JR Salvador A Portolés M 《Biochemical and biophysical research communications》2012,418(2):222-228
We investigate for the first time the influence of heart failure (HF) on nucleolar organization and proteins in patients with ischemic (ICM) or dilated cardiomyopathy (DCM). A total of 71 human hearts from ICM (n=38) and DCM (n=27) patients, undergoing heart transplantation and control donors (n=6), were analysed by western-blotting, RT-PCR and cell biology methods. When we compared protein levels according to HF etiology, nucleolin was increased in both ICM (117%, p<0.05) and DCM (141%, p<0.01). Moreover, mRNA expression were also upregulated in ICM (1.46-fold, p<0.05) and DCM (1.70-fold, p<0.05. Immunofluorescence studies showed that the highest intensity of nucleolin was into nucleolus (p<0.0001), and it was increased in pathological hearts (p<0.0001). Ultrastructure analysis by electron microscopy showed an increase in the nucleus and nucleolus size in ICM (17%, p<0.05 and 131%, p<0.001) and DCM (56%, p<0.01 and 69%, p<0.01). Nucleolar organization was influenced by HF irrespective of etiology, increasing fibrillar centers (p<0.001), perinucleolar chromatin (p<0.01) and dense fibrillar components (p<0.01). Finally, left ventricular function parameters were related with nucleolin levels in ischemic hearts (p<0.0001). The present study demonstrates that HF influences on morphology and organization of nucleolar components, revealing changes in the expression and in the levels of nucleolin protein. 相似文献
78.
The denitrification performance of a lab-scale anoxic rotating biological contactor (RBC) using landfill leachate with high
nitrate concentration was evaluated. Under a carbon to nitrogen ratio (C/N) of 2, the reactor achieved N-NO3
− removal efficiencies above 95% for concentrations up to 100 mg N-NO3
− l−1. The highest observed denitrification rate was 55 mg N-NO3
− l−1 h−1 (15 g N-NO3
− m−2 d−1) at a nitrate concentration of 560 mg N-NO3
− l−1. Although the reactor has revealed a very good performance in terms of denitrification, effluent chemical oxygen demand (COD)
concentrations were still high for direct discharge. The results obtained in a subsequent experiment at constant nitrate concentration
(220 mg N-NO3
− l−1) and lower C/N ratios (1.2 and 1.5) evidenced that the organic matter present in the leachate was non-biodegradable. A phosphorus
concentration of 10 mg P-PO4
3− l−1 promoted autotrophic denitrification, revealing the importance of phosphorus concentration on biological denitrification
processes. 相似文献
79.
Human Peroxin PEX3 Is Co‐translationally Integrated into the ER and Exits the ER in Budding Vesicles 下载免费PDF全文
Peter U. Mayerhofer Manuel Bañó‐Polo Ismael Mingarro Arthur E. Johnson 《Traffic (Copenhagen, Denmark)》2016,17(2):117-130
The long‐standing paradigm that all peroxisomal proteins are imported post‐translationally into pre‐existing peroxisomes has been challenged by the detection of peroxisomal membrane proteins (PMPs) inside the endoplasmic reticulum (ER). In mammals, the mechanisms of ER entry and exit of PMPs are completely unknown. We show that the human PMP PEX3 inserts co‐translationally into the mammalian ER via the Sec61 translocon. Photocrosslinking and fluorescence spectroscopy studies demonstrate that the N‐terminal transmembrane segment (TMS) of ribosome‐bound PEX3 is recognized by the signal recognition particle (SRP). Binding to SRP is a prerequisite for targeting of the PEX3‐containing ribosome?nascent chain complex (RNC) to the translocon, where an ordered multistep pathway integrates the nascent chain into the membrane adjacent to translocon proteins Sec61α and TRAM. This insertion of PEX3 into the ER is physiologically relevant because PEX3 then exits the ER via budding vesicles in an ATP‐dependent process. This study identifies early steps in human peroxisomal biogenesis by demonstrating sequential stages of PMP passage through the mammalian ER. 相似文献
80.
Dumont Henri J. Han Bo-Ping Guo Fei Fei Chen Hua Cheng Dan Liu Ping Xu Lei Sanoamuang La-Orsri Rietzler Arnola C. Xu Shaolin Vierstraete Andy Elias-Gutierrez Manuel 《Aquatic Ecology》2021,55(4):1207-1222
Aquatic Ecology - Diaphanosoma s.l., with 40+? described species, is the largest genus of the Sididae and the Ctenopoda, similar in many ways to the anomopod genus Daphnia. Here, we offer a c... 相似文献