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排序方式: 共有8192条查询结果,搜索用时 15 毫秒
91.
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Arianna Aprile Giovanna Palermo Antonio De Luca Roberta Pinalli Enrico Dalcanale Pasquale Pagliusi 《RSC advances》2018,8(29):16314
Reliable chemical sensors with high selectivity and sensitivity toward specific target molecules require rational synthesis of receptors, in-depth characterization of their complexation abilities and highly efficient transduction of the molecular recognition event. Here we report a steady-state and time-resolved fluorescence investigation of EtQxBox, a fluorescent conformationally blocked quinoxaline-based cavitand, aimed at assessing its selectivity toward aromatic versus non-aromatic analytes in solution. Fluorescence quenching of the EtQxBox in acetone is observed at increasing concentration of both aromatic (i.e. benzonitrile) and aliphatic (i.e. acetonitrile) compounds. The combination with fluorescence lifetime measurements permits to discriminate the predominantly static quenching of the aromatic analyte, due to non-fluorescent host–guest complex formation, from the mostly dynamic quenching of the non-aromatic compound, resulting from aspecific diffusive collisions between the fluorophore and the quencher. The equilibrium association constants for both the complexes have been estimated using Stern–Volmer model.We investigate the role of combined static and dynamic quenching in fluorescence transduction of benzonitrile and acetonitrile complexation by a rigid quinoxaline-based cavitand. 相似文献
93.
Aimo Alberto Pateras Konstantinos Stamatelopoulos Kimon Bayes-Genis Antoni Lombardi Carlo Mario Passino Claudio Emdin Michele Georgiopoulos Georgios 《Cardiovascular drugs and therapy / sponsored by the International Society of Cardiovascular Pharmacotherapy》2021,35(5):1067-1076
Cardiovascular Drugs and Therapy - Sacubitril/valsartan, vericiguat, and the sodium-glucose co-transporter-2 inhibitors (SGLT2i) dapagliflozin and empagliflozin proved effective in phase 3 trials... 相似文献
94.
Valerio Rosato Antonio Ascione Riccardo Nevola Anna Ludovica Fracanzani Guido Piai Vincenzo Messina Ernesto Claar Carmine Coppola Luca Fontanella Rosa Lombardi Laura Staiano Giovanna Valente Maria Chiara Fascione Chiara Giorgione Annalisa Mazzocca Raffaele Galiero Pasquale Perillo Aldo Marrone Ferdinando Carlo Sasso Luigi Elio Adinolfi Luca Rinaldi 《Journal of viral hepatitis》2022,29(1):26-34
The long-term changes of liver stiffness (LS) in patients who achieve viral clearance after direct-acting anti-HCV therapy remain undefined. We conducted a multicentre prospective study to investigate this aspect. Patients with HCV infection treated with DAAs were enrolled from six Italian centres; they underwent clinical, biochemical, ultrasound and transient elastography evaluations before treatment (T0), 12 weeks (SVR12) and 24 months (T24) after the end of therapy. Among the 516 consecutive patients enrolled, 301 had cirrhosis. LS significantly decreased from T0 to SVR (14.3 vs 11.1 kPa, p = .002), with a progressive reduction until T24 (8.7 kPa, p < .001). However, only patients with steatosis and those who developed HCC did not experience a late improvement in LS. Multivariate analysis of baseline and follow-up variables identified steatosis as the only independent predictor of failure of LS improvement (OR 1.802, p = .013). ROC curve analysis of the association of LS with the risk of developing HCC showed that SVR12 ≥14.0 kPa had the highest accuracy (sensitivity 82%, specificity 99%; AUC: 0.774). Multivariate analysis revealed that LS was the only variable independently associated with an increased risk of developing HCC (OR 6.470, p = .035). Achieving an SVR was associated with a progressive, long-term decline of LS, suggesting a late improvement in liver fibrosis, besides the resolution of inflammation. Fatty liver and the development of HCC interfered with late reduction of LS. Patients with an LS ≥14 kPa at 12 weeks after the end of treatment were at higher risk for developing HCC. 相似文献
95.
Pelargonio Gemma Di Monaco Antonio Guida Pietro Pellegrino Pier Luigi Vergara Pasquale Grimaldi Massimo Narducci Maria Lucia Tritto Massimo 《Journal of interventional cardiac electrophysiology》2022,63(1):125-132
Journal of Interventional Cardiac Electrophysiology - Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia, occurring in 1–2% of the general population. Catheter ablation... 相似文献
96.
Naga Venkata K. Pothineni MD Nigel Amankwah MD Pasquale Santangeli MD PhD Robert D. Schaller DO Gregory E. Supple MD Rajat Deo MD Saman Nazarian MD Fermin C. Garcia MD Sanjay Dixit MD David J. Callans MD Francis E. Marchlinski MD David S. Frankel MD 《Journal of cardiovascular electrophysiology》2021,32(2):345-353
97.
Pulcrano M Camera L Pagano L Del Vecchio S Ferone D Bodei L Murgia A Pace L Storto G Paganelli G Colao A Salvatore M Lombardi G Biondi B 《Journal of endocrinological investigation》2008,31(4):352-359
The identification of patients with von Hippel-Lindau (VHL) disease dictates accurate genetic counseling of family members, whereas screening for early detection of visceral and neurological involvement is usually performed by a combination of radiological and nuclear medicine techniques such as ultrasonography or contrast-enhanced computed tomography of the upper abdomen, magnetic resonance imaging of the central nervous system and 131I-metaiodobenzylguanidine-scintigraphy. The role of 111-indium-diethylenetriaminepentaacetic acid [111In-DTPA0] octreotide scintigraphy in this clinical context has never been investigated. Here, we report imaging findings in a VHL patient and in 3 consecutive family members undergoing clinical and radiological screening that included [111In-DTPA0] octreotide scintigraphy in addition to the above-mentioned procedures. Somatostatin receptor expression was investigated in vitro by immunohistochemistry in pancreatic tumor sections. On the basis of in vivo and in vitro findings, octreotide long-acting release treatment followed by 90Y-1,4,7,10-Tetraazacyclododecane-N,N',N',N'-tetraacetic acid (DOTA0)-Tyr3-octreotide led to a lack of progression in this patient although this result is a possibility which needs to be proved by further investigation and longer follow-up. The results of this study suggest that [111In-DTPA0] octreotide scintigraphy may be helpful in the routine work-up of VHL patients for diagnostic and therapeutic purposes. 相似文献
98.
Maria Teresa Sartori Graziella Saggiorato Donatella Pellati Federico Dal Bello Anna Maria Lombardi Giuseppe Opocher Luca Spiezia Antonio Girolami 《Clinical and applied thrombosis/hemostasis》2006,12(1):77-84
The absence or very low levels of plasminogen cause a rare disabling disease called ligneous conjunctivitis, characterized by the growth of fibrin-rich pseudomembranes in the conjunctiva and on other mucosal surfaces. Several mutations have been detected in the plasminogen gene of patients affected with ligneous conjunctivitis. The human plasminogen gene, located on chromosome 6, has a marked homology with the genes belonging to the plasminogen-apo(a) family, and with a number of pseudogenes and plasminogen-like genes located on chromosome 2. This work describes a series of nucleotide variations related to genes other than the plasminogen one, found during the genetic characterization of plasminogen defect in two unrelated patients with ligneous conjunctivitis. The results of automated sequences of each exon and intron-exon boundaries were compared with those of the human plasminogen gene from the NCBI gene bank. In particular, a co-amplified gene on chromosome 2 mimicking a 14 bp deletion in exon 5 of the plasminogen gene was identified by sequencing two different bands obtained from a long run of the PCR exon 5 product in NuSieve agarose gel, and by PstI restriction enzyme analysis of the same amplicons. Moreover, 21 single nucleotide exchanges due to plasminogen-like genes co-amplification were observed, namely one in exon 1, two in exon 4, three in exons 3, 5 and 16, four in exon 13, and five in exon 17. In conclusion, these data confirm the difficulty of plasminogen genetic analysis and may help researchers to better identify the true plasminogen gene mutations causing molecular defects. 相似文献
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