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排序方式: 共有659条查询结果,搜索用时 15 毫秒
81.
Arcamone N Lucini C Borzacchiello G Castaldo L Gargiulo G De Girolamo P 《Microscopy research and technique》2005,66(1):17-24
By means of immunochemistry and immunohistochemistry, we investigated in the kidney of freshwater and marine teleostean species for the presence and localization of three neurotrophins: nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), and neurotrophin (NT)-3. In both species studied, NGF-like and NT-3-like immunoreactivity were present in the kidney with different distribution patterns, while BDNF-like immunoreactivity was never detected. In goldfish, NGF-like and NT-3-like immunoreactivity were identified extensively in cells along part of the arterial branches adjacent to the afferent arterioles. In scorpion fish, NGF-like and NT-3-like immunoreactive cells were observed both on afferent arterioles and on adjacent secondary branches derived from renal arteries. No immunoreactivity was detected in other renal structures. A staining pattern of immunoreactivity similar to that obtained for NGF and NT-3 was detected utilizing S100 antibody as a juxtaglomerular (JG) cell marker. Double immunolabellings NGF/S100 and NT-3/S100 evidenced the coexistence of neurotrophin-like proteins and S100-like protein in the same immunoreactive cells, thus identifying them as juxtaglomerular cells. Western blot analysis revealed the presence of molecules immunoreactive to NGF and NT-3, whose molecular weights were very similar to those of the corresponding mammalian neurotrophins. These findings extend the presence and distribution of NGF-like and NT-3-like IR in the kidney to teleost species, suggesting a probable participation of these proteins in the renal functions of freshwater and marine teleosts. 相似文献
82.
83.
Luisa Torsi Francesco Marinelli M. Daniela Angione Antonio Dell’Aquila Nicola Cioffi Elvira De Giglio Luigia Sabbatini 《Organic Electronics》2009,10(2):233-239
Contact effects in organic thin-film transistors (OTFTs) sensors are here investigated specifically respect to the gate field-induced sensitivity enhancement of more than three orders of magnitude seen in a DHα6T OTFT sensor exposed to 1-butanol vapors. This study shows that such a sensitivity enhancement effect is largely ascribable to changes occurring to the transistor channel resistance. Effects, such as the changes in contact resistance, are seen to influence the low gate voltage regime where the sensitivity is much lower. 相似文献
84.
Angelone M Marinelli M Milani E Tucciarone A Pillon M Pucella G Verona-Rinati G 《Radiation protection dosimetry》2006,120(1-4):345-348
Polycrystalline chemical vapour deposited (CVD) diamond film is an interesting material for neutron detection and dosimetry. However, the use of CVD diamond detectors is still limited by the low-level signal pulse produced because of the high energy required to produce an electron-hole pair in diamond (13.2 eV) and by the reduced charge collection efficiency owing to several types of traps for electrons and holes in CVD films. A new type of CVD diamond detector with high gain (HG) contacts was produced as part of the collaboration between the ENEA Fusion Division and the Faculty of Engineering of Rome 'Tor Vergata' University. In this paper the performance of the HG CVD diamond detector is presented and possible applications of CVD diamond detectors to neutron dosimetry are also discussed. 相似文献
85.
Carla Luciana Gerez Maria Ines Torino Graciela Rollán Graciela Font de Valdez 《Food Control》2009,20(2):144-148
The ability of lactic acid bacteria (LAB) to inhibit Aspergillus, Fusarium, and Penicillium, the main contaminants in bread, was evaluated. Only four strains (Lactobacillus plantarum CRL 778, Lactobacillus reuteri CRL 1100, and Lactobacillus brevis CRL 772 and CRL 796) from 95 strains tested displayed antifungal activity. The major antifungal compounds were acetic and phenyllactic acids. The fermentation quotient (FQ = 2.0) and the leaven volume (80 cm3) of doughs with LB and yeasts were higher than doughs without LB. The inclusion of antifungal LAB strains in the starter culture allowed a reduction in the concentration of calcium propionate by 50% while still attaining a shelf life similar to that of traditional bread containing 0.4% CP. 相似文献
86.
87.
Suzane Lucas Schechtel Vanessa Cristina Rodrigues de Matos Jnio Sousa Santos Thiago Mendanha Cruz Mariza Boscacci Marques Mingchun Wen Liang Zhang Marianna Miranda Furtado Anderson S. Sant'Ana Mariana Araújo Vieira do Carmo Luciana Azevedo Jssica Caroline Bigaski Ribeiro Daniel Granato 《Journal of food science》2019,84(12):3473-3482
88.
89.
Rodríguez-Zúñiga UF Milori DM da Silva WT Martin-Neto L Oliveira LC Rocha JC 《Environmental science & technology》2008,42(6):1948-1953
Aquatic humic substances (AHS) isolated from two characteristic seasons of the Negro river, winter and summer corresponding to floody and dry periods, were structurally characterized by 13C nuclear magnetic ressonance. Subsequently, AHS aqueous solutions were irradiated with a polychromatic lamp (290-475 nm) and monitored by its total organic carbon (TOC) content, ultraviolet-visible (UV-vis) absorbance, fluorescence, and Fourier transformed infrared spectroscopy (FTIR). As a result, a photobleaching up to 80% after irradiation of 48 h was observed. Conformational rearrangements and formation of low molecular complexity structures were formed during the irradiation, as deduced from the pH decrement and the fluorescence shifting to lower wavelengths. Additionally a significant mineralization with the formation of CO2, CO, and inorganic carbon compounds was registered, as assumed by TOC losses of up to 70%. The differences in photodegradation between samples expressed by photobleaching efficiency were enhanced in the summer sample and related to its elevated aromatic content. Aromatic structures are assumed to have high autosensitization capacity effects mediated by the free radical generation from quinone and phenolic moieties. 相似文献
90.
Neil Gerard Quigley Dr. Stefano Tomassi Dr. Francesco Saverio di Leva Dr. Salvatore Di Maro Dr. Frauke Richter Dr. Katja Steiger Prof. Dr. Susanne Kossatz Prof. Dr. Luciana Marinelli Dr. Johannes Notni 《Chembiochem : a European journal of chemical biology》2020,21(19):2836-2843
αvβ6 Integrin is an epithelial transmembrane protein that recognizes latency-associated peptide (LAP) and primarily activates transforming growth factor beta (TGF-β). It is overexpressed in carcinomas (most notably, pancreatic) and other conditions associated with αvβ6 integrin-dependent TGF-β dysregulation, such as fibrosis. We have designed a trimeric Ga-68-labeled TRAP conjugate of the αvβ6-specific cyclic pentapeptide SDM17 (cyclo[RGD-Chg-E]-CONH2) to enhance αvβ6 integrin affinity as well as target-specific in-vivo uptake. Ga-68-TRAP(SDM17)3 showed a 28-fold higher αvβ6 affinity than the corresponding monomer Ga-68-NOTA-SDM17 (IC50 of 0.26 vs. 7.4 nM, respectively), a 13-fold higher IC50-based selectivity over the related integrin αvβ8 (factors of 662 vs. 49), and a threefold higher tumor uptake (2.1 vs. 0.66 %ID/g) in biodistribution experiments with H2009 tumor-bearing SCID mice. The remarkably high tumor/organ ratios (tumor-to-blood 11.2; -to-liver 8.7; -to-pancreas 29.7) enabled high-contrast tumor delineation in PET images. We conclude that Ga-68-TRAP(SDM17)3 holds promise for improved clinical PET diagnostics of carcinomas and fibrosis. 相似文献