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排序方式: 共有1091条查询结果,搜索用时 15 毫秒
991.
Diego Di Girolamo Fabio Matteocci Felix Utama Kosasih Ganna Chistiakova Weiwei Zuo Giorgio Divitini Lars Korte Caterina Ducati Aldo Di Carlo Danilo Dini Antonio Abate 《Liver Transplantation》2019,9(31)
In perovskite solar cells (PSCs), the interfaces are a weak link with respect to degradation. Electrochemical reactivity of the perovskite's halides has been reported for both molecular and polymeric hole selective layers (HSLs), and here it is shown that also NiO brings about this decomposition mechanism. Employing NiO as an HSL in p–i–n PSCs with power conversion efficiency (PCE) of 16.8%, noncapacitive hysteresis is found in the dark, which is attributable to the bias‐induced degradation of perovskite/NiO interface. The possibility of electrochemically decoupling NiO from the perovskite via the introduction of a buffer layer is explored. Employing a hybrid magnesium‐organic interlayer, the noncapacitive hysteresis is entirely suppressed and the device's electrical stability is improved. At the same time, the PCE is improved up to 18% thanks to reduced interfacial charge recombination, which enables more efficient hole collection resulting in higher Voc and FF. 相似文献
992.
Armato Caterina Ahmed Daniyal Agostino Valeria Traversi Deborah Degan Raffaella Tommasi Tonia Margaria Valentina Sacco Adriano Gilli Giorgio Quaglio Marzia Saracco Guido Schilirò Tiziana 《Bioprocess and biosystems engineering》2019,42(5):697-709
Bioprocess and Biosystems Engineering - The characterization of anodic microbial communities is of great importance in the study of microbial fuel cells (MFCs). These kinds of devices mainly... 相似文献
993.
Anelli T Ceppi S Bergamelli L Cortini M Masciarelli S Valetti C Sitia R 《The EMBO journal》2007,26(19):4177-4188
The biogenesis of secretory IgM occurs stepwise under stringent quality control, formation of μ2L2 preceding polymerization. How is efficiency of IgM secretion coupled to fidelity? We show here that ERp44, a soluble protein involved in thiol-mediated retention, interacts with ERGIC-53. Binding to this hexameric lectin contributes to ERp44 localization in the ER-golgi intermediate compartment. ERp44 and ERGIC-53 increase during B-lymphocyte differentiation, concomitantly with the onset of IgM polymerization. Both preferentially bind μ2L2 and higher order intermediates. Their overexpression or silencing in non-lymphoid cells promotes or decreases secretion of IgM polymers, respectively. In IgM-secreting B-lymphoma cells, μ chains interact first with BiP and later with ERp44 and ERGIC-53. Our findings suggest that ERGIC-53 provides a platform that receives μ2L2 subunits from the BiP-dependent checkpoint, assisting polymerization. In this process, ERp44 couples thiol-dependent assembly and quality control. 相似文献
994.
995.
Ghirri P Ladaki C Bartoli A Scirè G Vuerich M Spadoni GL Maiorana A Geremia C Boldrini A Cianfarani S 《Hormone research》2007,67(3):123-131
BACKGROUND/AIMS: Our aim was to investigate glucose homeostasis, insulin sensitivity and insulin-like growth factor (IGF) system status in children born small for gestational age (SGA). METHODS: A case-control study was carried out at birth, infancy and childhood, comparing SGA with children appropriate for gestational age strictly matched for age, gender, pubertal status and body mass index. Ninety newborns, 52 infants, and 68 children were studied. Fasting insulin (I(F)), fasting glucose (G(F)) to I(F) ratio (G(F)/I(F)), the homeostasis model assessment of insulin sensitivity, the quantitative insulin sensitivity check index, insulinogenic index and the triglyceride/high-density lipoprotein-cholesterol ratio were measured. IGF-I, IGF-binding protein-3 and the IGF-I/IGF-binding protein-3 molar ratio were assessed. RESULTS: Glucose concentrations were lower in SGA newborns (p < 0.0001), infants (p = 0.01), and children (p = 0.001). Birth weight correlated with glucose levels at birth (r = 0.59, p < 0.0001), 12 months (r = 0.29, p = 0.04) and childhood (r = 0.44, p < 0.0001). CONCLUSION: Our results provide evidence for a developmental adaptation of glucose metabolism in SGA children leading to reduced glucose concentrations. 相似文献
996.
Breda D Cusulin C Iannelli M Maset S Vermiglio R 《Journal of mathematical biology》2007,54(5):701-720
In this paper a numerical scheme to investigate the stability of linear models of age-structured population dynamics is studied.
The method is based on the discretization of the infinitesimal generator associated to the semigroup of the solution operator
by using pseudospectral differencing techniques, hence following the approach recently proposed in Breda et al. [SIAM J Sci
Comput 27(2): 482–495, 2005] for delay differential equations. The method computes the rightmost characteristic roots and
it is shown to converge with spectral accuracy behavior.
The research of Mimmo Iannelli was supported in part within the FIRB project RBAU01K7M2 “Metodi dell’Analisi Matematica in
Biologia, Medicina e Ambiente”. 相似文献
997.
Decreased plasma soluble RAGE in patients with hypercholesterolemia: effects of statins 总被引:2,自引:0,他引:2
Santilli F Bucciarelli L Noto D Cefalù AB Davì V Ferrante E Pettinella C Averna MR Ciabattoni G Davì G 《Free radical biology & medicine》2007,43(9):1255-1262
The receptor for advanced glycation endproducts (RAGE) is overexpressed at sites of vascular pathology. A soluble RAGE isoform (sRAGE) neutralizes the ligand-mediated damage by acting as a decoy. We hypothesized that in hypercholesterolemia up-regulation of the ligand-RAGE axis may bridge impairment of nitric oxide biosynthesis with oxidative stress. We measured in 60 hypercholesterolemic patients and 20 controls plasma total sRAGE levels, urinary 8-iso-prostaglandin (PG) F(2alpha) excretion, and plasma levels of asymmetric dimethylarginine (ADMA). The effects of two structurally different statins (pravastatin and atorvastatin) on these parameters were analyzed in 20 hypercholesterolemic subjects free of vascular disease. Plasma sRAGE was significantly lower, ADMA and urinary 8-iso-PGF(2alpha) were higher, in hypercholesterolemic versus normocholesterolemic patients. Patients on statin treatment with previous myocardial infarction had lower 8-iso-PGF(2alpha), higher sRAGE, and unchanged ADMA levels compared to subjects free of vascular disease. On multivariate regression analysis only 8-iso-PGF(2alpha) and ADMA predicted sRAGE levels. An 8-week treatment with either statin was associated with a significant reduction in urinary 8-iso-PGF(2alpha), whereas only atorvastatin raised sRAGE levels near to normal values, with no change in ADMA levels. sRAGE might serve as an endogenous protecting factor for accelerated atherosclerosis mediated by oxidative stress and endothelial dysfunction in hypercholesterolemia. 相似文献
998.
Heat and cold transduction by peripheral sensory neurons is a fundamental step in the avoidance of dangerous thermal extremes. In this issue of Neuron, Dhaka et al. and Colburn et al. report that mice lacking the cold- and menthol-gated ion channel TRPM8 exhibit deficient behavioral responses to cold temperatures. 相似文献
999.
Carluccio MA Ancora MA Massaro M Carluccio M Scoditti E Distante A Storelli C De Caterina R 《American journal of physiology. Heart and circulatory physiology》2007,293(4):H2344-H2354
Hyperhomocysteinemia is a recognized risk factor for vascular disease, but pathogenetic mechanisms involved in its vascular actions are largely unknown. Because VCAM-1 expression is crucial in monocyte adhesion and early atherogenesis, we evaluated the NF-kappaB-related induction of VCAM-1 by homocysteine (Hcy) and the possible inhibitory effect of dietary polyphenolic antioxidants, such as trans-resveratrol (RSV) and hydroxytyrosol (HT), which are known inhibitors of NF-kappaB-mediated VCAM-1 induction. In human umbilical vein endothelial cells (HUVEC), Hcy, at 100 micromol/l, but not cysteine, induced VCAM-1 expression at the protein and mRNA levels, as shown by enzyme immunoassay and Northern analysis, respectively. Transfection studies with deletional VCAM-1 promoter constructs demonstrated that the two tandem NF-kappaB motifs in the VCAM-1 promoter are necessary for Hcy-induced VCAM-1 gene expression. Hcy-induced NF-kappaB activation was confirmed by EMSA, as shown by the nuclear translocation of its p65 (RelA) subunit and the degradation of the inhibitors IkappaB-alpha and IkappaB-beta by Western analysis. Hcy also increased intracellular reactive oxygen species by NAD(P)H oxidase activation, as shown by the membrane translocation of its p47(phox) subunit. NF-kappaB inhibitors decreased Hcy-induced intracellular reactive oxygen species and VCAM-1 expression. Finally, we found that nutritionally relevant concentrations of RSV and HT, but not folate and vitamin B6, reduce (by >60% at 10(-6) mol/l) Hcy-induced VCAM-1 expression and monocytoid cell adhesion to the endothelium. These data indicate that pathophysiologically relevant Hcy concentrations induce VCAM-1 expression through a prooxidant mechanism involving NF-kappaB. Natural Mediterranean diet antioxidants can inhibit such activation, suggesting their possible therapeutic role in Hcy-induced vascular damage. 相似文献