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College alcohol drinking is a public health concern worldwide. A line of research indicates that higher social anxiety is associated with more severe college drinking. However, other studies reveal a protective role of social anxiety against alcohol drinking in college students. Attempting to reconcile contradictory findings, we examined the hypothesis that there are multiple antagonistic pathways that could explain the social anxiety-college drinking relationship. In addition, there may be individual difference variables that moderate these processes. Furthermore, it was expected that the processes could vary as a function of the alcohol drinking outcomes examined. Expectancy theory emphasizes the role of alcohol outcome expectancies in alcohol drinking. Thus, in the present study we tested whether global positive and negative alcohol outcome expectancies partially mediate the relationship between social anxiety, alcohol consumption, and alcohol-related problems in a sample of 245 university students. We also examined the moderating role of gender in these mediating processes. Results revealed parallel but oppositional processes. Higher social anxiety was associated with heavier alcohol drinking and more serious alcohol-related problems via stronger positive alcohol outcome expectancies. However, the mediating role of positive alcohol outcome expectancies varied as a function of gender. It appears that in female students the mediating effect of positive alcohol outcome expectancies was stronger than in male students. On the other hand, higher social anxiety had a protective role against alcohol consumption but not against alcohol-related problems via stronger negative alcohol outcome expectancies. Finally, there was an inverse direct relationship between social anxiety and alcohol consumption.  相似文献   
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Several Australian obesity management guidelines have been developed for general practice but, to date, implementation of these guidelines has been shown to be inadequate. In this review, we explore the barriers to obesity treatment and propose a four-stage plan to manage individuals with obesity in general practice using a framework of a multidisciplinary team.Funding: Novo Nordisk.  相似文献   
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PURPOSE: The aim of this study was to determine the epidemiological and the clinical characteristics of post-transplant lymphoproliferative disease (PTLD) and to evaluate its impact on patients' and grafts' survival. PATIENTS AND METHODS: Three hundred and sixteen adult kidney recipients, transplanted between June 1986 and May 2006, were included. The incidence rates were calculated by dividing the number of different events (PTLD, death and graft-loss) by the total duration of follow-up. The survival rates and the cumulated frequency of PTLD were calculated according to the actuarial method. RESULTS: Seven recipients developed PTLD during a cumulated follow-up of 2202 years. The annual incidence was of 0.32% (95% CI : 0.30-0.34). It was of 0.81% (0.70-0.92) in recipients of kidneys from deceased donors, and of 0.25% (0.23-0.27) in patients transplanted from living donors (NS). The delay after transplantation for the diagnosis of PTLD ranged from 7.4 months to 7.7 years. PTLD was a B cell lymphoma in six cases and affected extra nodal sites in most of the cases. The treatment, comprising the cessation of immunosuppressive therapy in all cases, resulted in complete remission in four patients. Three patients died, representing an annual death rate of 6.1%, versus 2.8% in patients without PTLD (NS). The annual incidence of graft loss was 6.1% versus 3.2% among patients without PTLD (NS). CONCLUSION: PTLD was observed in 2.2% of our patients, with an annual incidence of 0.32%. It resulted in a decrease of both patients' and grafts' survivals. Preventive measures, including the improvement of the monitoring of immunosuppressive drugs and the prevention of viral infections, should be considered to reduce the risk of PTLD.  相似文献   
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OBJECTIVES: Soluble transferrin receptor (sTfR) and zinc protoporphyrin (ZPP) are both parameters of iron deficient erythropoiesis (IDE), the sTfR measurement is commonly regarded to be the more sensitive test. sTfR also reflects erythropoietic activity, it is increased in enhanced erythropoiesis. METHODS: We investigated the diagnostic accuracy of sTfR in assessment of iron deficiency (ID) and compared it with ZPP. The study was performed on 174 subjects, in which ID has been precisely staged. RESULTS: Individuals without ID and patients with storage iron depletion only, had normal sTfR values. Patients classified as IDE and patients with iron deficiency anemia had significantly increased sTfR. There was a good correlation between sTfR and hemoglobin (r = -0.86; P < 0.0001) and between sTfR and ZPP (r = 0.86; P < 0.0001). When diagnosing ID, ZPP was the more sensitive test. In mildly developed IDE associated with ZPP-ratios between 40 and 70 micromol/mol heme, the sTfR concentration was elevated in only 25% of the cases. Reliably elevated sTfR values were observed only in more advanced IDE, associated with ZPP > 70 mumol/mol heme. CONCLUSIONS: ZPP is not inferior to sTfR when diagnosing IDE. Given the good correlation between sTfR and ZPP and because ZPP is uninfluenced by the erythropoietic activity, sTfR and ZPP are not competitors, rather efficient partners in diagnosing anemias. By measuring ZPP and sTfR simultaneously, the diagnostic uncertainty inherent in each of them individually can be eliminated. In particular, the simultaneous determination of ZPP and sTfR enhances the diagnostic power of sTfR in assessment of the erythropoietic activity.  相似文献   
46.
OBJECTIVE Previous studies of the effect of GH replacement on bone mass in adults with GH deficiency have produced conflicting results. We have studied the effect of 6 and 12 months of GH replacement on bone mass in adults with adult onset GH deficiency. DESIGN Double blind placebo controlled study of GH replacement (0.125 IU/kg/week for the first month and 0.25 IU/kg/week thereafter) for 6 months and an open study for a further 6 or 12 months. PATIENTS Twenty-two adults (10 men, 12 women), aged 41.5±2.1 years (mean ± SE, range 23.6–59.5), with adult onset GH deficiency. MEASUREMENTS Single-energy quantitative computed tomography was used to measure vertebral trabecular bone mineral density (BMD), single-photon absorptiometry (SPA) was used to measure forearm cortical and integral bone mineral content and BMD and dual-energy X-ray absorptiometry (DXA) was used to measure lumbar spine, femoral neck, trochanteric and Ward's triangle Integral BMD. RESULTS After 6 months of GH replacement (n=21) there was a significant decrease In forearm cortical BMD (SPA: median change ?0.009g/cm2, P=0.01), forearm Integral BMD (SPA: median change ?0.016g/cm2, P=0.03), lumbar spine BMD (DXA: median change ?0.022g/cm2; P=0.003) and femoral neck BMD (DXA: median change ?0.029g/cm2, P=0.006). After 12 months of GH replacement (n=13) there was a significant decrease in lumbar spine BMD (DXA: median change ?0.035 g/cm2, P=0.002) from baseline. There was no significant Increase in bone mass at any site after 6 or 12 months of GH replacement. Change In bone mass was not influenced by sex of the patient or by presence or absence of additional pituitary hormone deficiencies. CONCLUSION The response of bone mass to 6 and 12 months of GH replacement in adults with adult onset GH deficiency is disappointing. Longer-term studies are required to determine whether prolonged GH replacement has a beneficial effect on bone mass.  相似文献   
47.
Indoleamine 2,3-dioxygenase (IDO) suppresses adaptive immunity. T-cell proliferation and differentiation to effector cells require increased glucose consumption, aerobic glycolysis and glutaminolysis. The effect of IDO on the above metabolic pathways was evaluated in alloreactive T-cells. Mixed lymphocyte reaction (MLR) in the presence or not of the IDO inhibitor, 1-methyl-dl-tryptophan (1-MT), was used. In MLRs, 1-MT decreased tryptophan consumption, increased cell proliferation, glucose influx and lactate production, whereas it decreased tricarboxylic acid cycle activity. In T-cells, from the two pathways that could sense tryptophan depletion, i.e. general control nonrepressed 2 (GCN2) kinase and mammalian target of rapamycin complex 1, 1-MT reduced only the activity of the GCN2 kinase. Additionally 1-MT treatment of MLRs altered the expression and/or the phosphorylation state of glucose transporter-1 and of key enzymes involved in glucose metabolism and glutaminolysis in alloreactive T-cells in a way that favors glucose influx, aerobic glycolysis and glutaminolysis. Thus in alloreactive T-cells, IDO through activation of the GCN2 kinase, decreases glucose influx and alters key enzymes involved in metabolism, decreasing aerobic glycolysis and glutaminolysis. Acting in such a way, IDO could be considered as a constraining factor for alloreactive T-cell proliferation and differentiation to effector T-cell subtypes.  相似文献   
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Platelet derived growth factor (PDGF) is involved in the autocrine growth stimulation of normal and malignant cells, the stimulation of angiogenesis, and the recruitment and regulation of tumor fibroblasts. PDGF has been shown to physically interact with glycosaminoglycans which are abundant in the extracellular microenvironment. The present review discusses the effects of glycosaminoglycans on the functions mediated by the PDGF on cells of mesenchymal origin. Recent studies have demonstrated that both soluble and surface bound glycosaminoglycan chains can modulate PDGF-BB isoform signaling depending on the cell type. These data demonstrated that the microenvironment rich in GAGs/PGs is able to significantly modify the cellular response to PDGF-BB signaling in a critical way for cell growth and differentiation.  相似文献   
50.
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