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171.
172.
Provencher V Bégin C Tremblay A Mongeau L Boivin S Lemieux S 《Obesity (Silver Spring, Md.)》2007,15(4):957-966
Objective: To assess the effects of a “Health‐At‐Every‐Size” (HAES) intervention on eating behaviors and appetite ratings in 144 premenopausal overweight women. Research Methods and Procedures: Women were randomly assigned to one of the 3 groups: HAES group, social support (SS) group, and control group (N = 48 in each group). Interventions were conducted over a 4‐month period, and measurements were taken before and after this period. Eating behaviors (cognitive dietary restraint, disinhibition, and susceptibility to hunger) were evaluated by the Three‐Factor Eating Questionnaire. Appetite ratings (desire to eat, hunger, fullness, and prospective food consumption) were assessed by visual analogue scales before and after a standardized breakfast. Results: More important decreases in susceptibility to hunger and external hunger were observed in the HAES group when compared with the SS group (p = 0.05, for susceptibility to hunger) and the control group (p = 0.02 and p = 0.005, for susceptibility to hunger and external hunger, respectively). In addition, women from the HAES group had more important decreases in postprandial area under the curve for desire to eat (p = 0.02) and hunger (p = 0.04) when compared with the control group. The change in the desire to eat noted in the HAES group was also different from the one observed in SS group (p = 0.02). Women from the HAES group experienced significant weight loss at 4 months (?1.6 ± 2.5 kg, p < 0.0001), which did not differ significantly from the SS and control groups (p = 0.09). An increase in flexible restraint was significantly related to a greater weight loss in both HAES and SS groups (r = ?0.39, p < 0.01; and r = ?0.37, p < 0.05, respectively). A decrease in habitual susceptibility to disinhibition was also associated with a greater weight loss in HAES and control groups (r = 0.31, p < 0.05; and r = 0.44, p < 0.05, respectively). Discussion: These results suggest that a HAES intervention could have significant effects on eating behaviors and appetite ratings in premenopausal overweight women, when compared with an SS intervention or a control group. 相似文献
173.
174.
Barbara Repetto Alberto Palenzona Simone Cagnacci Eugenio A. Debbia Anna Marchese 《Annals of microbiology》2007,57(3):439-442
Pseudomonas aeruginosa is an opportunistic pathogen, intrinsically resistant to many antibiotics and prone to acquire resistance against many drugs. It is assumed that agents that disorganise the structure of the outer membrane might allow the passage of other drugs into cell. To verify this hypothesis, ceftazidime (CAZ) has been tested in association with glycopeptides (GLYs) and azithromycin (AZI). Time-kill experiments were performed on a representative strain. CAZ in combination with GLYs showed 99, 90 and 10% of CFU/ml reduction in 33.9,52.5 and 13.6% of the cases, respectively; the addition of AZI increased the incidence of 99% CFU/ml reduction to 42% of the cases. Indifference was the most common finding, and additive/synergism in the other cases. Present findings demonstrated that CAZ favourably reacted with GLYs in the presence of AZI. 相似文献
175.
Milda Stuknytė Simone Guglielmetti Giovanni Ricci Nomeda Kuisienė Diego Mora Carlo Parini Donaldas Čitavičius 《Annals of microbiology》2007,57(3):407-414
We repor the first data demonstrating the presence of putative conjugative transfer genes on plasmids of the speciesGeobacillus stearothermophilus. Partial sequence analysis of the plasmid pGS18 fromG. stearothermophilus 18 was determined. It contained eleven complete open reading frames. Five of them encoded proteins which are homologous toBacillus megaterium pBM300 Mob/TraA,Lactococcus lactis pMRC01 TrsD and TrsE,Staphylococcus aureus pGO1 TrsG andS. aureus subsp.aureus pUSA03 TraL, the proteins that are associated with conjugative plasmid transfer. Southern hybridizations were performed on two other plasmids isolated fromG. stearothermophilus 3 andG. stearothermophilus 19 strains using the most homologous parts of those five genes as probes. Data from different hybridization patterns show a close homology of putative conjugative transfer genes between pGS18 and pGS3 hypothesizing a similar molecular organization of putative conjugative plasmid transfer region of both plasmids. 相似文献
176.
Soncini M Vesentini S Ruffoni D Orsi M Deriu MA Redaelli A 《Biomechanics and modeling in mechanobiology》2007,6(6):399-407
Alpha-actinin is a cytoskeleton-binding protein involved in the assembly and regulation of the actin filaments. In this work
molecular dynamics method was applied to investigate the mechanical behaviour of the human skeletal muscle α-actinin. Five
configurations were unfolded at an elongation speed of 0.1 nm/ps in order to investigate the conformational changes occurring
during the extension process. Moreover, a sensitivity analysis at different velocities was performed for one of the R2–R3
spectrin-like repeat configuration extracted in order to evaluate the effect of the pulling speed on the mechanical behaviour
of the molecule. Two different behaviours were recognized with respect to the pulling speed. In particular, at speed higher
than 0.025 nm/ps a continuous rearrangement without evident force peaks was obtained, on the contrary at lower speed evident
peaks in the range 500–750 pN were detected. R3 repeat resulted more stable than R2 during mechanical unfolding, due to the
lower hydrophobic surface available to the solvent. The characterization of the R2–R3 units can be useful for the development
of cytoskeleton network models based on stiffness values obtained by analyses performed at the molecular level. 相似文献
177.
Endogenous phosphotyrosine signaling in zebrafish embryos 总被引:1,自引:0,他引:1
Lemeer S Ruijtenbeek R Pinkse MW Jopling C Heck AJ den Hertog J Slijper M 《Molecular & cellular proteomics : MCP》2007,6(12):2088-2099
In the developing embryo, cell growth, differentiation, and migration are strictly regulated by complex signaling pathways. One of the most important cell signaling mechanisms is protein phosphorylation on tyrosine residues, which is tightly controlled by protein-tyrosine kinases and protein-tyrosine phosphatases. Here we investigated endogenous phosphotyrosine signaling in developing zebrafish embryos. Tyrosine phosphorylated proteins were immunoaffinity-purified from zebrafish embryos at 3 and 5 days postfertilization and identified by multidimensional LC-MS. Among the identified proteins were tyrosine kinases, including Src family kinases, Eph receptor kinases, and focal adhesion kinases, as well as the adaptor proteins paxillin, p130Cas, and Crk. We identified several known and some unknown in vivo tyrosine phosphorylation sites in these proteins. Whereas most immunoaffinity-purified proteins were detected at both developmental stages, significant differences in abundance and/or phosphorylation state were also observed. In addition, multiplex in vitro kinase assays were performed by incubating a microarray of peptide substrates with the lysates of the two developmental stages. Many of the in vivo observations were confirmed by this on-chip in vitro kinase assay. Our experiments are the first to show that global tyrosine phosphorylation-mediated signaling can be studied at endogenous levels in complex multicellular organisms. 相似文献
178.
Frauenschuh S Reichmann E Ibold Y Goetz PM Sittinger M Ringe J 《Biotechnology progress》2007,23(1):187-193
Microcarrier cultures have been shown to allow extensive cell expansion of tissue engineering relevant cells, such as chondrocytes, while maintaining their phenotype. Our aim was to investigate the in vitro three-dimensional expansion of porcine bone-marrow-derived primary mesenchymal stem cells (MSC) using commercially available Cytodex type 1, type 2, and type 3 microcarriers. In comparison, the Cytodex type 1 microcarriers showed the best results for adherence with over 80% adherent cells after 3 h of incubation, analyzed by the Poisson distribution. Different start cell densities ranging from 1 to 3 x 106 cells per 100 cm2 had only a minor influence on adhesion. The proliferation was examined on Cytodex type 1 microcarriers over a cultivation time of 28 days, which could reveal cell growth and proof of cells recolonizing freshly added microcarriers. Scanning electron microscopy displayed appropriate cell morphology and confirmed cell proliferation. After enzymatic harvest from microcarriers, the osteogenic and chondrogenic differentiation of these cells was induced and shown by relevant histochemistry, such as von Kossa and Alcian blue staining. Totaling the results, we have shown that the three-dimensional expansion of MSC on microcarriers represents a beneficial alternative to the conventional two-dimensional monolayer cultivation method. 相似文献
179.
Thomas Kastner Sarah Matej Matthew Forrest Simone Gingrich Helmut Haberl Thomas Hickler Fridolin Krausmann Gitta Lasslop Maria Niedertscheider Christoph Plutzar Florian Schwarzmüller Jrg Steinkamp Karl-Heinz Erb 《Global Change Biology》2022,28(1):307-322
Land use has greatly transformed Earth's surface. While spatial reconstructions of how the extent of land cover and land-use types have changed during the last century are available, much less information exists about changes in land-use intensity. In particular, global reconstructions that consistently cover land-use intensity across land-use types and ecosystems are missing. We, therefore, lack understanding of how changes in land-use intensity interfere with the natural processes in land systems. To address this research gap, we map land-cover and land-use intensity changes between 1910 and 2010 for 9 points in time. We rely on the indicator framework of human appropriation of net primary production (HANPP) to quantify and map land-use-induced alterations of the carbon flows in ecosystems. We find that, while at the global aggregate level HANPP growth slowed down during the century, the spatial dynamics of changes in HANPP were increasing, with the highest change rates observed in the most recent past. Across all biomes, the importance of changes in land-use areas has declined, with the exception of the tropical biomes. In contrast, increases in land-use intensity became the most important driver of HANPP across all biomes and settings. We conducted uncertainty analyses by modulating input data and assumptions, which indicate that the spatial patterns of land use and potential net primary production are the most critical factors, while spatial allocation rules and uncertainties in overall harvest values play a smaller role. Highlighting the increasing role of land-use intensity compared to changes in the areal extent of land uses, our study supports calls for better integration of the intensity dimension into global analyses and models. On top of that, we provide important empirical input for further analyses of the sustainability of the global land system. 相似文献
180.
Carisio Luca Cerri Jacopo Lioy Simone Bianchi Ettore Bertolino Sandro Porporato Marco 《Journal of Insect Conservation》2022,26(4):663-671
Journal of Insect Conservation - Invasive alien species could generate a multitude of impacts towards native species. The introduction and spread of Vespa velutina in Europe is raising concern for... 相似文献