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61.

Background  

Overweight is reported as a side effect of SDR. The aims were to study the development of weight, height and body mass index (BMI) during five years after SDR.  相似文献   
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A three-week mesocosm experiment was conducted in order to study the effects of bottom sediment and nutrient enrichment on phytoplankton and zooplankton community structure in the Archipelago Sea, northern Baltic Sea. The transparent polyethylene enclosures included the whole water column and varied in volume from 30 to 40 m3. There were two types of enclosures: some with natural sediment as a bottom and others with a plastic bottom. The experiment was a 2 × 2 factorial design with presence of sediment and nutrient enrichment as treatment factors. Both the sediment presence and nutrient enrichment significantly increased water nutrient concentrations and the rate of primary production. However, external nutrient enrichment and the presence of sediment stimulated the growth of different phytoplankton groups, indicating that the effect of sediment was not related to nutrient fluxes alone, but involved more complex interactions. External nutrient enrichment was primarily channelled to picoplanktonic cyanobacteria, the biomass of which increased four- to fivefold due to enrichment. The presence of sediment increased the biomass of cryptophytes, chrysophytes and prasinophytes, but decreased the biomass of N2-fixing cyanobacteria. Zooplankton biomass increased during the experiment, but was not affected by the treatments. The study shows that sediment plays a significant role in phytoplankton dynamics, underlining the importance of including sediment in shallow-water mesocosm experiments. Handling editor: J. Padisak  相似文献   
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OBJECTIVE: To determine the proliferation rates of mesothelial cells in metastatic and benign effusions. STUDY DESIGN: Immunohistochemistry was performed on formalin-fixed pellets from 16 malignant and 9 benign clinical effusions. Dual staining with antibodies against Ki-67 (MIB-1) and desmin was applied to all effusions to differentiate between benign mesothelial cells and malignant cells, and the proportions of desmin+/Ki-67+ and desmin+/Ki-67- cells were calculated. RESULTS: In 7 malignant effusions no proliferating mesothelial cells were found, whereas some rate of proliferation could always be demonstrated in mesothelial cells in the benign effusions. Further, the median proportions of proliferating cells, malignant 2% vs. benign 11%, differed significantly. CONCLUSIONS: To our knowledge this finding has not been previously described, and it may have implications for both cytologic diagnosis and the understanding of tumor biology and the interaction between tumor cells and mesothelial cells.  相似文献   
67.

Background  

Pathogenic yersiniae (Y. pestis, Y. pseudotuberculosis, Y. enterocolitica) share a virulence plasmid encoding a type three secretion system (T3SS). This T3SS comprises more than 40 constituents. Among these are the transport substrates called Yops (Yersinia outer proteins), the specific Yop chaperones (Sycs), and the Ysc (Yop secretion) proteins which form the transport machinery. The effectors YopO and YopP are encoded on an operon together with SycO, the chaperone of YopO. The characterization of SycO is the focus of this study.  相似文献   
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In mammals, glucocorticoids (GCs) and their intracellular receptor, the glucocorticoid receptor (GR), represent critical checkpoints in the endocrine control of energy homeostasis. Indeed, aberrant GC action is linked to severe metabolic stress conditions as seen in Cushing's syndrome, GC therapy and certain components of the Metabolic Syndrome, including obesity and insulin resistance. Here, we identify the hepatic induction of the mammalian conserved microRNA (miR)‐379/410 genomic cluster as a key component of GC/GR‐driven metabolic dysfunction. Particularly, miR‐379 was up‐regulated in mouse models of hyperglucocorticoidemia and obesity as well as human liver in a GC/GR‐dependent manner. Hepatocyte‐specific silencing of miR‐379 substantially reduced circulating very‐low‐density lipoprotein (VLDL)‐associated triglyceride (TG) levels in healthy mice and normalized aberrant lipid profiles in metabolically challenged animals, mediated through miR‐379 effects on key receptors in hepatic TG re‐uptake. As hepatic miR‐379 levels were also correlated with GC and TG levels in human obese patients, the identification of a GC/GR‐controlled miRNA cluster not only defines a novel layer of hormone‐dependent metabolic control but also paves the way to alternative miRNA‐based therapeutic approaches in metabolic dysfunction.  相似文献   
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