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1.
Nonpigmenting fixed exanthema from ephedrine and pseudoephedrine   总被引:2,自引:2,他引:0  
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S-adenosyl-L-methionine (SAM) has shown efficacy in speeding the onset of the antidepressant effect of imipramine in depressed patients. This effect may be related to their interactions at the serotonin(1A) (5-HT(1A)) receptors. Acute imipramine up-regulated the frontal cortex 5-HT(1A) receptors (B(max), 51.5 +/- 8.4 fmol/mg protein) vs. saline (B(max), 27.5 +/- 5.9 fmol/mg protein), and did not show antidepressant effect. Acute SAM and imipramine+SAM did not modify frontal cortex 5-HT(1A) receptors, and showed antidepressant effects (decrease of the immobility response of 26%, P<0.01; and 47%, P<0.001) vs. saline. All the chronic treatments showed antidepressant effects and up-regulated the hippocampus 5-HT(1A) receptors. SAM prevents the 5-HT(1A) receptor up-regulation induced by acute imipramine in the frontal cortex. This mechanism may contribute to imipramine's antidepressant effect.  相似文献   
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This article presents an optimal control strategy (OCS) for semiactive vehicle suspensions with road profile sensors. The suspension is modeled as a quarter‐car model with a magnetorheological (MR) damper. The OCS main objective is to minimize the fourth‐power acceleration of the sprung mass. In addition, three pointwise constraints of the model are taken into account when the optimal control problem is solved: suspension travel limits (upper and lower) and tyre vertical force. In order to deal with a large number of constraints, we implement the gradient optimization method based on the method of moving asymptotes routine, which shows very good performance reaching optimal controls while satisfying the constrains. The solution has been compared with two passive MR damper configurations (low and high damping) as well as Skyhook and Balance control strategies for three different road inputs. Results show that OCS fulfills the constraints and reduces the sprung mass acceleration peak and the root‐mean‐quad acceleration up to 59% , in comparison to passive strategies.  相似文献   
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Lipid rafts are required for GLUT4 internalization in adipose cells   总被引:8,自引:0,他引:8       下载免费PDF全文
It has been recently reported that insulin recruits a novel signaling machinery to lipid rafts required for insulin-stimulated GLUT4 translocation [Baumann, A., Ribon, V., Kanzaki, M., Thurmond, D. C., Mora, S., Shigematsu, S., Bickel, P. E., Pessin, J. E. & Saltiel, A. R. (2001) Nature 407, 202-207, 2000; Chiang, S. H., Baumann, C. A., Kanzaki, M., Thurmond, D. C., Watson, R. T., Neudauer, C. L., Macara, I. G., Pessin, J. E. & Saltiel, A. R. (2001) Nature 410, 944-948]. We have assessed the role of lipid rafts on GLUT4 traffic in adipose cells. High GLUT4 levels were detected in caveolae from adipocytes by two approaches, the mechanical isolation of purified caveolae from plasma membrane lawns and the immunogold analysis of plasma membrane lawns followed by freeze-drying. The role of lipid rafts in GLUT4 trafficking was studied by adding nystatin or filipin at concentrations that specifically disrupt caveolae morphology and inhibit caveolae function without altering clathrin-mediated endocytosis. These caveolae inhibitors did not affect the insulin-stimulated glucose transport. However, they blocked both the GLUT4 internalization and the down-regulation of glucose transport triggered by insulin removal in 3T3-L1 adipocytes. Our data indicate that lipid rafts are crucial for GLUT4 internalization after insulin removal. Given that high levels of GLUT4 were detected in caveolae from insulin-treated adipose cells, this transporter may be internalized from caveolae or caveolae may operate as an obligatory transition station before internalization.  相似文献   
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Standardization of sequence chromatogram analysis is required for consistent genotypic tropism determination across laboratories. A freely available, fast, and automated chromatogram analysis tool (RECall) provided tropism interpretations equivalent to those of manual sequence editing of 521 V3 loop HIV-1 population sequences, suggesting that RECall can be useful in standardizing genotypic tropism testing across laboratories.  相似文献   
10.
The progressive increase in the number of liver transplantation candidates has brought with it a consequent increase in waiting list mortality, making it necessary to revise donor selection criteria and to analyze the factors that optimize outcomes. This retrospective observational study of 1802 liver transplantations performed in Andalusia between 2000 and 2010 analyzes the outcomes from donors aged 70 years or older (n = 211) in terms of survival rates of the graft and the recipient, the type of transplant, donor age, and DMELD (Donor-Model for End-Stage Liver Disease) score. The most frequent reasons for transplantation were alcoholic cirrhosis (45.5%), hepatitis C cirrhosis (20.4%), and liver cancer (11.8%). The overall survival rate at 5 years was 67%; with a significant decrease in survival rates for recipients with a DMELD greater than 1400 (44%). In the 70-year-old-plus donor group, the overall patient and graft survival rates were 57% and 52%, respectively. The re-transplantation rate increased proportionately with donor age: 5.9% between 70 and 74 years, 9.5% from 75 to 79 years, and 17.6% from 80 to 84 years. In the alcoholic cirrhosis recipient sub-group, the overall survival rate at 5 years was 69% (P < .05) compared to 34% in hepatitis C patients (P < .05). The widening of the donor age selection criteria is therefore a safe option, provided that a DMELD score less than 1400 is obtained. Although re-transplantation rates increase progressively with donor age, they remain less than 10%. It is necessary to carefully screen recipients of older organs, taking into account that the best results are obtained for patients who have alcoholic cirrhosis, are hepatitis C negative, and have a DMELD score that is less than 1400.  相似文献   
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