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排序方式: 共有7812条查询结果,搜索用时 15 毫秒
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Johnson Sonia Dalton-Locke Christian Vera San Juan Norha Foye Una Oram Sian Papamichail Alexandra Landau Sabine Rowan Olive Rachel Jeynes Tamar Shah Prisha Sheridan Rains Luke Lloyd-Evans Brynmor Carr Sarah Killaspy Helen Gillard Steve Simpson Alan 《Social psychiatry and psychiatric epidemiology》2021,56(1):25-37
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Irina S. Vasil'eva Galina P. Shumakovich Maria E. Khlupova Roman B. Vasiliev Viktor V. Emets Vera A. Bogdanovskaya Olga V. Morozova Alexander I. Yaropolov 《RSC advances》2020,10(55):33010
The development of novel materials with improved functional characteristics for supercapacitor electrodes is of current concern and calls for elaboration of innovative approaches. We report on an eco-friendly enzymatic synthesis of a composite based on poly(3,4-ethylenedioxythiophene) (PEDOT) and multi-walled carbon nanotubes (MWCNTs). The redox active compound, sodium 1,2-naphthoquinone-4-sulfonate (NQS), was used as a dopant for the backbone of the polymer. Oxidative polymerization of 3,4-ethylenedioxythiophene (EDOT) was catalyzed by a high redox potential laccase from the fungus Trametes hirsuta. Atmospheric oxygen served as an oxidant. A uniform thin layer of NQS-doped PEDOT formed on the surface of MWCNTs as a result of the enzymatic polymerization. The PEDOT–NQS/MWCNT composite showed a high specific capacitance of ca. 575 F g−1 at a potential scan rate of 5 mV s−1 and an excellent cycling stability within a potential window between −0.5 and 1.0 V, which makes it a promising electrode material for high-performance supercapacitors.The use of redox active NSQ as a dopant of PEDOT dramatically increases the specific capacitance and cyclic stability of enzymatically synthesized PEDOT–NSQ/MWCNT composite. 相似文献
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Renata Nunes Cabral Bente Nyvad Vera Ligia Vieira Mendes Soviero Eduardo Freitas Soraya Coelho Leal 《Clinical oral investigations》2020,24(2):727-734
To describe a new molar-incisor hypomineralization (MIH) severity scoring system (MIH-SSS) that focuses on the defects’ severity and to assess the sy 相似文献
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Luis Larrea Emma Castro Belén Vera María-Jesús Vayá Nuria Yagüe Vicente Mirabet Cristina Arbona 《Transfusion and apheresis science》2021,60(1):102915
Cryopreservation of hematopoietic stem cells (HSC) involves slow rate cooling in the presence of a cryoprotectant (DMSO) to avoid the damaging effects of intracellular ice formation. The infusion of DMSO with the thawed product has been related to adverse events. Reduction of DMSO content by washing the HSCs after thawing has been suggested as a method to avoid infusion-related side-effects. Albumin-dextran washing methods have proved useful in thawing HSC products. Dextran40 shortages prompted us to search for suitable alternatives. We report the results of a comparative study of the use of hydroxyethyl starch (HES) as an alternative to dextran40 for washing thawed HSCs products. A total of 10 HSC bags cryopreserved with 10 % DMSO were used. We conducted a paired study; one of the bags was thawed and washed with our standard washing solution (Dextran 40) and the paired bag with HES solution with a final HES and Human Serum Albumin (HSA) concentration of 2.4 % and 4.2 % respectively. Each final product was tested immediately after washing (sample 0’) and after 90 min (sample 90’) for total nucleated cells (TNC) recovery, acridine orange viability, viable CD34+ enumeration, and clonogenicity. No significant difference was found for any of the cell counts, viability tests, cell recovery, or potency. We can state that the washing solution based on 2.4 % HES and 4.2 % HSA is equivalent to that used in our routine practice. Therefore, we could use the solution with HES, paying special attention to the renal function of the recipient. 相似文献
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Tineke van de Weijer Esther Phielix Lena Bilet Evan G. Williams Eduardo R. Ropelle Alessandra Bierwagen Roshan Livingstone Peter Nowotny Lauren M. Sparks Sabina Paglialunga Julia Szendroedi Bas Havekes Norman Moullan Eija Pirinen Jong-Hee Hwang Vera B. Schrauwen-Hinderling Matthijs K.C. Hesselink Johan Auwerx Michael Roden Patrick Schrauwen 《Diabetes》2015,64(4):1193-1201
Recent preclinical studies showed the potential of nicotinamide adenine dinucleotide (NAD+) precursors to increase oxidative phosphorylation and improve metabolic health, but human data are lacking. We hypothesize that the nicotinic acid derivative acipimox, an NAD+ precursor, would directly affect mitochondrial function independent of reductions in nonesterified fatty acid (NEFA) concentrations. In a multicenter randomized crossover trial, 21 patients with type 2 diabetes (age 57.7 ± 1.1 years, BMI 33.4 ± 0.8 kg/m2) received either placebo or acipimox 250 mg three times daily dosage for 2 weeks. Acipimox treatment increased plasma NEFA levels (759 ± 44 vs. 1,135 ± 97 μmol/L for placebo vs. acipimox, P < 0.01) owing to a previously described rebound effect. As a result, skeletal muscle lipid content increased and insulin sensitivity decreased. Despite the elevated plasma NEFA levels, ex vivo mitochondrial respiration in skeletal muscle increased. Subsequently, we showed that acipimox treatment resulted in a robust elevation in expression of nuclear-encoded mitochondrial gene sets and a mitonuclear protein imbalance, which may indicate activation of the mitochondrial unfolded protein response. Further studies in C2C12 myotubes confirmed a direct effect of acipimox on NAD+ levels, mitonuclear protein imbalance, and mitochondrial oxidative capacity. To the best of our knowledge, this study is the first to demonstrate that NAD+ boosters can also directly affect skeletal muscle mitochondrial function in humans. 相似文献
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Johnson C Waters DD DeMicco DA Breazna A Bittner V Greten H Grundy SM LaRosa JC 《The American journal of cardiology》2008,102(10):1312-1317
The Treating to New Targets (TNT) study demonstrated that intensive atorvastatin therapy to achieve low-density lipoprotein cholesterol concentrations well below recommended target levels provides an incremental clinical benefit in patients with stable coronary artery disease. This post hoc analysis of the TNT study was conducted to investigate whether this benefit extends to patients with previous percutaneous coronary intervention (PCI). A total of 10,001 patients with clinically evident coronary artery disease, including 5,407 patients with previous PCI, were randomized to atorvastatin 10 or 80 mg/day and followed for a median of 4.9 years. The primary end point was the occurrence of a first major cardiovascular event. Revascularization, a component of a secondary end point, was also examined. In patients with previous PCI, mean low-density lipoprotein cholesterol levels at study end were 79.5 mg/dl in the 80-mg arm and 100.8 mg/dl in the 10-mg arm. First major cardiovascular events occurred in 230 patients (8.6%) receiving high-dose atorvastatin and 289 patients (10.6%) receiving low-dose atorvastatin (hazard ratio 0.79, 95% confidence interval 0.67 to 0.94, p = 0.008). Repeat revascularization during follow-up (PCI or coronary artery bypass grafting) was performed in 466 patients (17.3%) in the 80-mg arm and 624 patients (22.9%) in the 10-mg arm (hazard ratio 0.73, 95% confidence interval 0.65 to 0.82, p <0.0001). In conclusion, intensive lipid lowering to a mean low-density lipoprotein cholesterol level of 79.5 mg/dl (2.1 mmol/L) with atorvastatin 80 mg/day in patients with previous PCI reduces major cardiovascular events by 21% and repeat revascularizations by 27% compared with a less intensive lipid-lowering regimen. 相似文献