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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
Angela Notarnicola Roberto Tamma Lorenzo Moretti Alessandra Fiore Giovanni Vicenti Alberta Zallone Biagio Moretti 《Musculoskeletal surgery》2012,96(3):183-189
Radial shock waves therapy (RSWT) differs from extracorporeal shock waves therapy (ESWT) in that it produces a non-focused wave that is dissipated radially at the skin. Few studies have yet explored the effects of RSWT on bone tissue. Osteoblasts in culture flasks were studied by polymerase chain reaction after treatment with RSW (500 impulses, 0.05?mJ/mm2). An inhibited osteoblastogenesis was observed, with a statistically significant reduction in type 1 collagen, osterix, bone sialoprotein and receptor activator NF kappa ligand expression at 24 and 48?h, of osteocalcin at 24, 48 and 72?h, and osteopontin at 48 and 72?h. These findings show that RSWT is not indicated for treatment of delayed fracture union, pseudoarthrosis, and complex regional pain syndrome. The observed reduction in the receptor activator of nuclear factor-kB ligand/osteoprotegerin ratio suggests that it has an inhibiting effect on osteoclastogenesis, which could make it a useful tool for applications in proliferative diseases. 相似文献
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Leonardo Furi Maria Laura Ciusa Daniel Knight Valeria Di Lorenzo Nadia Tocci Daniela Cirasola Lluis Aragones Joana Rosado Coelho Ana Teresa Freitas Emmanuela Marchi Laura Moce Pilar Visa John Blackman Northwood Carlo Viti Elisa Borghi Graziella Orefici the BIOHYPO Consortium Ian Morrissey Marco Rinaldo Oggioni 《Antimicrobial agents and chemotherapy》2013,57(8):3488-3497
The MICs and minimum bactericidal concentrations (MBCs) for the biocides benzalkonium chloride and chlorhexidine were determined against 1,602 clinical isolates of Staphylococcus aureus. Both compounds showed unimodal MIC and MBC distributions (2 and 4 or 8 mg/liter, respectively) with no apparent subpopulation with reduced susceptibility. To investigate further, all isolates were screened for qac genes, and 39 of these also had the promoter region of the NorA multidrug-resistant (MDR) efflux pump sequenced. The presence of qacA, qacB, qacC, and qacG genes increased the mode MIC, but not MBC, to benzalkonium chloride, while only qacA and qacB increased the chlorhexidine mode MIC. Isolates with a wild-type norA promoter or mutations in the norA promoter had similar biocide MIC distributions; notably, not all clinical isolates with norA mutations were resistant to fluoroquinolones. In vitro efflux mutants could be readily selected with ethidium bromide and acriflavine. Multiple passages were necessary to select mutants with biocides, but these mutants showed phenotypes comparable to those of mutants selected by dyes. All mutants showed changes in the promoter region of norA, but these were distinct from this region of the clinical isolates. Still, none of the in vitro mutants displayed fitness defects in a killing assay in Galleria mellonella larvae. In conclusion, our data provide an in-depth comparative overview on efflux in S. aureus mutants and clinical isolates, showing also that plasmid-encoded efflux pumps did not affect bactericidal activity of biocides. In addition, current in vitro tests appear not to be suitable for predicting levels of resistance that are clinically relevant. 相似文献
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Splenic lymphangiomatosis in children 总被引:14,自引:0,他引:14
98.
Juan M. Díaz-Tocados María E. Rodríguez-Ortiz Yolanda Almadén Carmen Pineda Julio M. Martínez-Moreno Carmen Herencia Noemi Vergara M. Victoria Pendón-Ruiz de Mier Rafael Santamaría Cristian Rodelo-Haad Antonio Casado-Díaz Víctor Lorenzo Catarina Carvalho João M. Frazão Arnold J. Felsenfeld William G. Richards Escolástico Aguilera-Tejero Mariano Rodríguez Juan R. Muñoz-Castañeda 《Kidney international》2019,95(5):1064-1078
99.
Martina Giovannella Bjrn Andresen Julie B Andersen Sahla El-Mahdaoui Davide Contini Lorenzo Spinelli Alessandro Torricelli Gorm Greisen Turgut Durduran Udo M Weigel Ian Law 《Journal of cerebral blood flow and metabolism》2020,40(10):2055
Diffuse correlation spectroscopy (DCS) can non-invasively and continuously asses regional cerebral blood flow (rCBF) at the cot-side by measuring a blood flow index (BFI) in non-traditional units of cm2/s. We have validated DCS against positron emission tomography using 15O-labeled water (15O-water PET) in a piglet model allowing us to derive a conversion formula for BFI to rCBF in conventional units (ml/100g/min). Neonatal piglets were continuously monitored by the BabyLux device integrating DCS and time resolved near infrared spectroscopy (TRS) while acquiring 15O-water PET scans at baseline, after injection of acetazolamide and during induced hypoxic episodes. BFI by DCS was highly correlated with rCBF (R = 0.94, p < 0.001) by PET. A scaling factor of 0.89 (limits of agreement for individual measurement: 0.56, 1.39)×109× (ml/100g/min)/(cm2/s) was used to derive baseline rCBF from baseline BFI measurements of another group of piglets and of healthy newborn infants showing an agreement with expected values. These results pave the way towards non-invasive, cot-side absolute CBF measurements by DCS on neonates. 相似文献
100.
Paola Cassoni Lorenzo Daniele Elena Maldi Luisella Righi Veronica Tavaglione Silvia Novello Marco Volante Giorgio Vittorio Scagliotti & Mauro Papotti 《Histopathology》2009,55(1):20-27
Aims: To study caveolin-1 (Cav-1) expression in metastatic lung carcinomas.
Methods and results: Cav-1 expression was investigated in a series of 121 lung carcinomas and it was shown that 18/121 tumours (14.9%) were Cav-1+. None of the pure bronchioloalveolar carcinomas proved to be positive, vs. 42.8% of the large cell carcinomas (neuroendocrine subtype excluded). Adenocarcinomas (8.5%), large cell neuroendocrine carcinomas (20%) and squamous cell carcinomas (29.6%) displayed an intermediate percentage of positive cases, suggesting a gradient of Cav-1 expression according to tumour histotype-related aggressiveness. Moreover, the percentage of Cav-1+ tumours with distant metastases was almost double that of non-metastatic tumours (17.8% vs. 8.1%), irrespective of the histotype. In 34 tumours metastatic to the brain, primary and secondary lesions were compared and 53% of brain metastases were Cav-1+ vs. 20.6% of primaries, indicating a de novo acquisition of Cav-1 expression. This pattern was exclusive to the brain, as it was not acquired in adrenal metastases. In our series, the presence of epidermal growth factor receptor amplification, determined by fluorescence in situ hybridization, was not related to Cav-1 reactivity.
Conclusions: Cav-1 immunoreactivity in lung carcinoma is histotype-dependent and acquired de novo in brain metastases, suggesting a site-specific phenotypic shift in secondary lesions. 相似文献
Methods and results: Cav-1 expression was investigated in a series of 121 lung carcinomas and it was shown that 18/121 tumours (14.9%) were Cav-1+. None of the pure bronchioloalveolar carcinomas proved to be positive, vs. 42.8% of the large cell carcinomas (neuroendocrine subtype excluded). Adenocarcinomas (8.5%), large cell neuroendocrine carcinomas (20%) and squamous cell carcinomas (29.6%) displayed an intermediate percentage of positive cases, suggesting a gradient of Cav-1 expression according to tumour histotype-related aggressiveness. Moreover, the percentage of Cav-1+ tumours with distant metastases was almost double that of non-metastatic tumours (17.8% vs. 8.1%), irrespective of the histotype. In 34 tumours metastatic to the brain, primary and secondary lesions were compared and 53% of brain metastases were Cav-1+ vs. 20.6% of primaries, indicating a de novo acquisition of Cav-1 expression. This pattern was exclusive to the brain, as it was not acquired in adrenal metastases. In our series, the presence of epidermal growth factor receptor amplification, determined by fluorescence in situ hybridization, was not related to Cav-1 reactivity.
Conclusions: Cav-1 immunoreactivity in lung carcinoma is histotype-dependent and acquired de novo in brain metastases, suggesting a site-specific phenotypic shift in secondary lesions. 相似文献