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排序方式: 共有192条查询结果,搜索用时 15 毫秒
101.
Nadia Arcamone Simona Neglia Giuliana Gargiulo Vincenzo Esposito Ettore Varricchio Pietro Battaglini Paolo De Girolamo Finizia Russo 《Microscopy research and technique》2009,72(7):525-533
The occurrence and localization of ghrelin peptide in the gastrointestinal tract of Carassius auratus and Dicentrarchus labrax, two fish species that exhibit different feeding behavior, different habitats, and different anatomical organizations of the gastroenteric tract, were examined by immunohistochemical methods and western blotting analysis. All of the gastrointestinal segments studied displayed immunohistochemical localizations of ghrelin peptide. Numerous single or clustered immunoreactive cells were found along the gastric folds, particularly in the pyloric region of Dicentrarcus labrax, whereas scattered ghrelin immunoreactive cells were observed in the intestinal epithelium of both fish species. Double immunolabeling PGP 9.5/ghrelin demonstrated the localization of ghrelin peptide also in nerve fibers and neuronal cells of the submucosal and myenteric plexuses, often in association with vascular structures. Western blotting analysis confirmed the presence of ghrelin peptide in the gatrointestinal tract of both species studied, whose molecular weight was similar to that of the corresponding mammalian prepro-ghrelin. The findings could support the hypothesis that this peptide is an important appetite regulator in fish and could confirm the presence of the ghrelin peptide, starting from its precursor proteins, in the gastrointestinal tract of the goldfish and the sea bass. Microsc. Res. Tech. 2009. © 2009 Wiley-Liss, Inc. 相似文献
102.
Roberta Masella Claudio Giovannini Rosaria Varì Roberta Di Benedetto Ettore Coni Roberto Volpe Nadia Fraone Antonello Bucci 《Lipids》2001,36(11):1195-1202
The aim of this study was to assess the effects of the dietary intake of extra virgin olive oil on the oxidative susceptibility
of low density lipoproteins (LDL) isolated from the plasma of hyperlipidemic patients. Ten patients with combined hyperlipidemia
(mean plasma cholesterol 281 mg/dL, triglycerides 283 mg/dL) consumed a low-fat, low-cholesterol diet, with olive oil (20
g/d) as the only added fat, with no drug or vitamin supplementation for 6 wk. Then they were asked to replace the olive oil
they usually consumed with extra virgin olive oil for 4 wk. LDL were isolated at the beginning, and after the 4 wk of dietary
treatment. LDL susceptibility to CuSO4-mediated oxidation was evaluated by measuring the extent of lipid peroxidation. We also determined fatty acid composition
and vitamin E in plasma and LDL and plasma phenolic content. Extra virgin olive oil intake did not affect fatty acid composition
of LDL but significantly reduced the copper-induced formation of LDL hydroperoxides and lipoperoxidation end products as well
as the depletion of LDL linoleic and arachidonic acid. A significant increase in the lag phase of conjugated diene formation
was observed after dietary treatment. These differences are statistically correlated with the increase in plasma phenolic
content observed at the end of the treatment with extra virgin olive oil; they are not correlated with LDL fatty acid composition
or vitamin E content, which both remained unmodified after the added fat change. This report suggests that the daily intake
of extra virgin olive oil in hyperlipidemic patients could reduce the susceptibility of LDL to oxidation, not only because
of its high monounsaturated fatty acid content but probably also because of the antioxidative activity of its phenolic compounds. 相似文献
103.
Ettore Fornasini 《Multidimensional Systems and Signal Processing》1991,2(3):233-265
The paper presents some applications of 2-D systems theory to the problem of modeling the river pollution processes and the associated selfpurification phenomena. The dynamical evolution of the biological oxygen demand (BOD) and the dissolved oxygen (DO) in a one-dimensional river model is discussed under various physical assumptions. 相似文献
104.
V. Fridkin G. Dalba P. Fornasini Y. Soldo F. Rocca E. Burattini 《Ferroelectrics Letters Section》1993,16(1):1-5
In LiNbO3, crystals the Bulk Photovoltaic Effect (BPE) under X-ray synchrotron radiation has been revealed. We observed this effect in LiNbO3,: Fe both in visible light and under synchrotron irradiation for energies 4-10 KeV. The photovoltaic current in the visible and X-ray region has opposite directions. It may be connected with two different mechanisms of the BPE: ballistic and shift. The combined effect, caused by light and X-ray, is investigated. 相似文献
105.
Cosimelli B Taliani S Greco G Novellino E Sala A Severi E Da Settimo F La Motta C Pugliesi I Antonioli L Fornai M Colucci R Blandizzi C Daniele S Trincavelli ML Martini C 《ChemMedChem》2011,6(10):1909-1918
A number of quinolines and isoquinolines connected in various ways to a substituted benzimidazol-2-yl system were synthesized and evaluated as novel antagonists of adenosine receptors (ARs) by competition experiments using human A(1), A(2A), and A(3) ARs. The new compounds were designed based on derivatives of 2-(benzimidazol-2-yl)quinoxaline, previously reported as potent and selective antagonists of A(1) and A(3) ARs. Among these, 3-[4-(ethylthio)-1H-benzimidazol-2-yl]isoquinoline 4b exhibited the best combination of potency toward the A(1) AR (K(i) =1.4 nM) and selectivity against the A(2A) (K(i) >10 μM), A(2B) (K(i)>10 μM), and A(3) ARs (K(i)>1 μM). Functional experiments in circular smooth muscle preparations of isolated human colon showed that 4b behaves as a potent and selective antagonist of the A(1) AR in the neuromuscular compartment of this intestinal region. Biological and pharmacological data suggest that 4b is a suitable starting point for the development of novel agents endowed with stimulant properties on colonic activity. 相似文献
106.
Cinzia Maria Chinnici Gioacchin Iannolo Ettore Cittadini Anna Paola Carreca David Nascari Francesca Timoneri Mariangela Di Bella Nicola Cuscino Giandomenico Amico Claudia Carcione Pier Giulio Conaldi 《International journal of molecular sciences》2021,22(4)
Despite low levels of vascular endothelial growth factor (VEGF)-A, the secretome of human Wharton’s jelly (WJ) mesenchymal stromal cells (MSCs) effectively promoted proangiogenic responses in vitro, which were impaired upon the depletion of small (~140 nm) extracellular vesicles (EVs). The isolated EVs shared the low VEGF-A profile of the secretome and expressed five microRNAs, which were upregulated compared to fetal dermal MSC-derived EVs. These upregulated microRNAs exclusively targeted the VEGF-A gene within 54 Gene Ontology (GO) biological processes, 18 of which are associated with angiogenesis. Moreover, 15 microRNAs of WJ-MSC-derived EVs were highly expressed (Ct value ≤ 26) and exclusively targeted the thrombospondin 1 (THBS1) gene within 75 GO biological processes, 30 of which are associated with the regulation of tissue repair. The relationship between predicted microRNA target genes and WJ-MSC-derived EVs was shown by treating human umbilical-vein endothelial cells (HUVECs) with appropriate doses of EVs. The exposure of HUVECs to EVs for 72 h significantly enhanced the release of VEGF-A and THBS1 protein expression compared to untreated control cells. Finally, WJ-MSC-derived EVs stimulated in vitro tube formation along with the migration and proliferation of HUVECs. Our findings can contribute to a better understanding of the molecular mechanisms underlying the proangiogenic responses induced by human umbilical cord-derived MSCs, suggesting a key regulatory role for microRNAs delivered by EVs. 相似文献
107.
108.
109.
Among the various chiroptical spectroscopic techniques available today, circularly polarized luminescence (CPL) plays a minor role and is still used by a limited number of specialists. The cost of the few commercial instruments available and the complexity of homemade apparatuses have strongly limited the widespread application of this technique. New technological approaches, such as the use of light-emitting diode (LED) sources, may significantly simplify the required instrumentation and encourage new potential users. Calibration procedure and the quantitative determination of CPL and total luminescence intensity as well as the corresponding g ratio are described. 相似文献
110.