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81.
We analyze the behavior of a series of newly synthesized (R-NH3)2PbX4 perovskites and, in particular, discuss the possible reasons which cause their degradation under UV illumination. Experimental results show that the degradation process depends a lot on their molecular components: not only the inorganic part, but also the chemical structure of the organic moieties play an important role in bleaching and photo-chemical reaction processes which tend to destroy perovskites luminescent framework. In addition, we find the spatial arrangement in crystal also influences the photostability course. Following these trends, we propose a plausible mechanism for the photodegradation of the films, and also introduced options for optimized stability.  相似文献   
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Context: Dietary fibers have been associated with a reduced incidence of type 2 diabetes mellitus in epidemiological studies; however, the precise mechanisms are unknown. Objective: The objective of the study was to evaluate the efficacy and site of action of an insoluble dietary fiber derived from maize (HAM-RS2) in improving insulin resistance in subjects at increased risk of type 2 diabetes mellitus. Design: This study was a randomized, controlled crossover, dietary intervention study. Setting: The study was conducted at the Centre for Diabetes, Endocrinology, and Research, Royal Surrey County Hospital, Guildford, United Kingdom. Participants: Fifteen men and women with insulin resistance participated in the study. Intervention: The intervention included 40 g/d HAM-RS2 compared with a matched placebo for 8 wk. Main Outcome Measures: After each supplement, participants underwent a two-step hyperinsulinemic-euglycemic clamp study with the addition of glucose tracers; a meal tolerance test; arteriovenous sampling across forearm muscle tissue; and a sc adipose tissue biopsy for assessment of gene expression. Results: There was enhanced uptake of glucose into the forearm muscle measured by arteriovenous sampling (65 ± 15% increase after resistant starch; P < 0.001). Adipose tissue function was also affected, with enhanced fatty acid suppression after HAM-RS2 treatment and an increase in gene expression for hormone sensitive lipase (P = 0.005), perilipin (P = 0.011), lipoprotein lipase (P = 0.014), and adipose triglyceride lipase (P = 0.03) in biopsy samples. There was no effect on the insulin sensitivity of hepatic glucose production or plasma lipids after HAM-RS2. Conclusion: HAM-RS2 improved peripheral but not hepatic insulin resistance and requires further study as an intervention in patients with or at risk for type 2 diabetes.  相似文献   
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Aims  

To evaluate the utility of laser microdissection in the comparison of phenotypes and genetic alterations between colon cancer and corresponding liver metastasis in the context of intratumoral heterogeneity.  相似文献   
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Data on the clinical spectrum and therapeutic management of noninfectious mixed cryoglobulinemia vasculitis (CryoVas) in the era of hepatitis C virus screening are lacking. We analyzed data from 242 patients with noninfectious mixed CryoVas included in the French multicenter CryoVas survey. Baseline manifestations were purpura (75%), peripheral neuropathy (52%), arthralgia or arthritis (44%), glomerulonephritis (35%), cutaneous ulcers (16%), and cutaneous necrosis (14%). A connective tissue disease was diagnosed in 30% and B-cell non-Hodgkin lymphoma in 22%, whereas the CryoVas was considered to be essential in 48%. With the use of Cox-marginal structural models, rituximab plus corticosteroids showed the greater therapeutic efficacy compared with corticosteroids alone and alkylating agents plus corticosteroids to achieve complete clinical, renal, and immunologic responses and a prednisone dosage < 10 mg/d at 6 months. However, this regimen was also associated with severe infections, particularly when high doses of corticosteroids were used, whereas death rates did not differ between the therapeutic regimens. The role of each of these strategies remains to be defined in well-designed randomized controlled trials.  相似文献   
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Because information on management and outcome of AML relapse after allogeneic hematopoietic stem cell transplantation (HSCT) with reduced intensity conditioning (RIC) is scarce, a retrospective registry study was performed by the Acute Leukemia Working Party of EBMT. Among 2815 RIC transplants performed for AML in complete remission (CR) between 1999 and 2008, cumulative incidence of relapse was 32% ± 1%. Relapsed patients (263) were included into a detailed analysis of risk factors for overall survival (OS) and building of a prognostic score. CR was reinduced in 32%; remission duration after transplantation was the only prognostic factor for response (P = .003). Estimated 2-year OS from relapse was 14%, thereby resembling results of AML relapse after standard conditioning. Among variables available at the time of relapse, remission after HSCT > 5 months (hazard ratio [HR] = 0.50, 95% confidence interval [CI], 0.37-0.67, P < .001), bone marrow blasts less than 27% (HR = 0.53, 95% CI, 0.40-0.72, P < .001), and absence of acute GVHD after HSCT (HR = 0.67, 95% CI, 0.49-0.93, P = .017) were associated with better OS. Based on these factors, 3 prognostic groups could be discriminated, showing OS of 32% ± 7%, 19% ± 4%, and 4% ± 2% at 2 years (P < .0001). Long-term survival was achieved almost exclusively after successful induction of CR by cytoreductive therapy, followed either by donor lymphocyte infusion or second HSCT for consolidation.  相似文献   
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