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Molecular and Cellular Biochemistry - Deuterium (D) is a stable isotope of hydrogen (H) with a mass number of 2. It is present in natural waters in the form of HDO, at a concentration of...  相似文献   
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Set‐shifting and maintenance are complex cognitive processes, which are often impaired in schizophrenia. The genetic basis of these processes is poorly understood. We aimed to investigate the association between genetic variants of the metabotropic glutamate receptor 3 (GRM3) and cognitive set‐shifting in healthy individuals. The relationship between 14 selected single nucleotide polymorphisms (SNPs) of the GRM3 gene and cognitive set‐shifting as measured by perseverative errors using the modified card sorting test (MCST) was analysed in a sample of N = 98 young healthy individuals (mean age in years: 22.7 ± 0.19). Results show that SNP rs17676277 is related to the performance on the MCST. Subjects with the TT genotype showed significantly less perseverative errors as compared with the AA (P = 0.025) and AT (P = 0.0005) and combined AA/AT genotypes (P = 0.0005). Haplotype analyses suggest the involvement of various SNPs of the GRM3 gene in perseverative error processing in a dominant model of inheritance. The findings strongly suggest that the genetic variation (rs17676277 and three haplotypes) in the metabotropic GRM3 is related to cognitive set‐shifting in healthy individuals independent of working memory. However, because of a relatively small sample size for a genetic association study, the present results are tentative and require replication.  相似文献   
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The work presents the data on the immunostimulating properties of neuropeptides. As revealed in this study, the leu-enkephalin level in blood sera (taken from 55 patients) inversely correlates with the intensity of the proliferative response of lymphocytes to phytohemagglutinin. In in vitro systems dalargin promotes the increase or decrease of the proliferative response of lymphocytes to phytohemagglutinin, depending on the proliferative activity of cells in response to this mitogen, and also leads to an increase in the number of rosette-forming cells. Leu-enkephalin in doses of 100, 10, 1, 0.1 micrograms/ml and dalargin in a dose of 0.1 microgram/ml inhibit the migration of leukocytes.  相似文献   
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It was shown that the ability of sheep and horse haptoglobins differing in their immunological properties to inhibit PGH synthetase is about the same. It was found that haptoglobin inhibits the PGH synthetase-catalyzed enzymatic reaction, the inhibiting effect being non-competitive with respect to the electron donor, adrenaline. The degree of PGH synthetase inhibition by haptoglobin depends on the glycoprotein concentration, incubation time and enzyme activity.  相似文献   
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Drosophila melanogaster sarcomere length short (SALS) is a recently identified Wiskott-Aldrich syndrome protein homology 2 (WH2) domain protein involved in skeletal muscle thin filament regulation. SALS was shown to be important for the establishment of the proper length and organization of sarcomeric actin filaments. Here, we present the first detailed characterization of the biochemical activities of the tandem WH2 domains of SALS (SALS-WH2). Our results revealed that SALS-WH2 binds both monomeric and filamentous actin and shifts the monomer-filament equilibrium toward the monomeric actin. In addition, SALS-WH2 can bind to but fails to depolymerize phalloidin- or jasplakinolide-bound actin filaments. These interactions endow SALS-WH2 with the following two major activities in the regulation of actin dynamics: SALS-WH2 sequesters actin monomers into non-polymerizable complexes and enhances actin filament disassembly by severing, which is modulated by tropomyosin. We also show that profilin does not influence the activities of the WH2 domains of SALS in actin dynamics. In conclusion, the tandem WH2 domains of SALS are multifunctional regulators of actin dynamics. Our findings suggest that the activities of the WH2 domains do not reconstitute the presumed biological function of the full-length protein. Consequently, the interactions of the WH2 domains of SALS with actin must be tuned in the cellular context by other modules of the protein and/or sarcomeric components for its proper functioning.  相似文献   
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Eric Allan  Wolfgang W. Weisser  Markus Fischer  Ernst-Detlef Schulze  Alexandra Weigelt  Christiane Roscher  Jussi Baade  Romain L. Barnard  Holger Beßler  Nina Buchmann  Anne Ebeling  Nico Eisenhauer  Christof Engels  Alexander J. F. Fergus  Gerd Gleixner  Marlén Gubsch  Stefan Halle  Alexandra M. Klein  Ilona Kertscher  Annely Kuu  Markus Lange  Xavier Le Roux  Sebastian T. Meyer  Varvara D. Migunova  Alexandru Milcu  Pascal A. Niklaus  Yvonne Oelmann  Esther Pašalić  Jana S. Petermann  Franck Poly  Tanja Rottstock  Alexander C. W. Sabais  Christoph Scherber  Michael Scherer-Lorenzen  Stefan Scheu  Sibylle Steinbeiss  Guido Schwichtenberg  Vicky Temperton  Teja Tscharntke  Winfried Voigt  Wolfgang Wilcke  Christian Wirth  Bernhard Schmid 《Oecologia》2013,173(1):223-237
In order to predict which ecosystem functions are most at risk from biodiversity loss, meta-analyses have generalised results from biodiversity experiments over different sites and ecosystem types. In contrast, comparing the strength of biodiversity effects across a large number of ecosystem processes measured in a single experiment permits more direct comparisons. Here, we present an analysis of 418 separate measures of 38 ecosystem processes. Overall, 45 % of processes were significantly affected by plant species richness, suggesting that, while diversity affects a large number of processes not all respond to biodiversity. We therefore compared the strength of plant diversity effects between different categories of ecosystem processes, grouping processes according to the year of measurement, their biogeochemical cycle, trophic level and compartment (above- or belowground) and according to whether they were measures of biodiversity or other ecosystem processes, biotic or abiotic and static or dynamic. Overall, and for several individual processes, we found that biodiversity effects became stronger over time. Measures of the carbon cycle were also affected more strongly by plant species richness than were the measures associated with the nitrogen cycle. Further, we found greater plant species richness effects on measures of biodiversity than on other processes. The differential effects of plant diversity on the various types of ecosystem processes indicate that future research and political effort should shift from a general debate about whether biodiversity loss impairs ecosystem functions to focussing on the specific functions of interest and ways to preserve them individually or in combination.  相似文献   
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DNA integrity is under the control of multiple pathways of nucleotide metabolism and DNA damage recognition and repair. Unusual sets of protein factors involved in these control mechanisms may result in tolerance and accumulation of non-canonical bases within the DNA. We investigate the presence of uracil in genomic DNA of Drosophila melanogaster. Results indicate a developmental pattern and strong correlations between uracil-DNA levels, dUTPase expression and developmental fate of different tissues. The intriguing lack of the catalytically most efficient uracil-DNA glycosylase in Drosophila melanogaster may be a general attribute of Holometabola and is suggested to be involved in the specific characteristics of uracil-DNA metabolism in these insects.  相似文献   
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Extremophiles - The strain Pseudomonas aeruginosa san ai, isolated from an extreme environment (industrial mineral cutting oil, pH 10), is able to survive and persist in the presence of a variety...  相似文献   
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