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排序方式: 共有5721条查询结果,搜索用时 31 毫秒
51.
Borsari V Giavaresi G Fini M Torricelli P Tschon M Chiesa R Chiusoli L Salito A Volpert A Giardino R 《Biomaterials》2005,26(24):4948-4955
A new implant surface has been developed with the purpose of avoiding as much stress shielding as possible, and thus prolong the prosthesis lifespan. The aim of this study was to investigate the in vitro effect of this new ultra-high roughness and dense Titanium (Ti) surface (PG60, Ra = 74 microm) in comparison with medium (TI01, Ra = 18 microm) and high (TI60, Ra = 40 microm) roughness and open porous coatings; all the coatings were obtained by vacuum plasma spraying. MG63 osteoblast-like cells were seeded on the tested materials and polystyrene, as control, for 3 and 7 days. Cells proliferated on the material surfaces similarly to the control. Alkaline phosphatase activity had lower values for TI60 than TI01 (p < 0.0005) and PG60 (p < 0.005). Osteocalcin levels measured on TI60 were significantly (p < 0.0005) lower in comparison with TI01 and PG60 at 7 days. Procollagen-I synthesis reduced with increasing roughness and the lowest data was found for PG60. While at 3 days Transforming Growth Factor beta1 levels augmented with increasing roughness, at 7 days TI60, the high roughness surface, was significantly lower than PG60 (p < 0.005) and TI01 (p < 0.001). All tested materials showed significantly higher Interleukin-6 levels than those of polystyrene at both experimental times. Nitric Oxide activity on TI01 was significantly (p < 0.05) higher than on TI60 and polystyrene. In conclusion, the new ultra-high roughness and dense coating PG60 provided a good biological response, even though, at least in vitro, it behaved similarly to the coatings already used in orthopaedics. 相似文献
52.
Ideomotor apraxia in patients with dementia of alzheimer type 总被引:1,自引:0,他引:1
Summary Ideomotor apraxia was checked in a carefully selected group of patients with Alzheimer's dementia, all in the mild stage of the disease. It was shown that ideomotor apraxia is not an early neuropsychological feature. When compared with other cognitive measures, the speed of deterioration of ideomotor apraxia appears to be particularly slow.Study supported by grant from the Consiglio Nazionale delle Ricerche (No. 8001829). Preliminary data presented at the XXIV Annual Meeting of the Italian Neurological Society (Pisa, October 1985) 相似文献
53.
Type 2 diabetes mellitus (T2DM) represents a major health burden for the elderly population, affecting approximately 25% of people over the age of 65 years. This percentage is expected to increase dramatically in the next decades in relation to the increased longevity of the population observed in recent years. Beyond microvascular and macrovascular complications, sarcopenia has been described as a new diabetes complication in the elderly population. Increasing attention has been paid by researchers and clinicians to this age-related condition—characterized by loss of skeletal muscle mass together with the loss of muscle power and function—in individuals with T2DM; this is due to the heavy impact that sarcopenia may have on physical and psychosocial health of diabetic patients, thus affecting their quality of life. The aim of this narrative review is to provide an update on: (1) the risk of sarcopenia in individuals with T2DM, and (2) its association with relevant features of patients with T2DM such as age, gender, body mass index, disease duration, glycemic control, presence of microvascular or macrovascular complications, nutritional status, and glucose-lowering drugs. From a clinical point of view, it is necessary to improve the ability of physicians and dietitians to recognize early sarcopenia and its risk factors in patients with T2DM in order to make appropriate therapeutic approaches able to prevent and treat this condition. 相似文献
54.
Gabriele Piuri Monica Zocchi Matteo Della Porta Valentina Ficara Michele Manoni Gian Vincenzo Zuccotti Luciano Pinotti Jeanette A. Maier Roberta Cazzola 《Nutrients》2021,13(2)
Magnesium (Mg2+) deficiency is probably the most underestimated electrolyte imbalance in Western countries. It is frequent in obese patients, subjects with type-2 diabetes and metabolic syndrome, both in adulthood and in childhood. This narrative review aims to offer insights into the pathophysiological mechanisms linking Mg2+ deficiency with obesity and the risk of developing metabolic syndrome and type 2 diabetes. Literature highlights critical issues about the treatment of Mg2+ deficiency, such as the lack of a clear definition of Mg2+ nutritional status, the use of different Mg2+ salts and dosage and the different duration of the Mg2+ supplementation. Despite the lack of agreement, an appropriate dietary pattern, including the right intake of Mg2+, improves metabolic syndrome by reducing blood pressure, hyperglycemia, and hypertriglyceridemia. This occurs through the modulation of gene expression and proteomic profile as well as through a positive influence on the composition of the intestinal microbiota and the metabolism of vitamins B1 and D. 相似文献
55.
Ricciardi Luca Stifano Vito Pucci Resi Stumpo Vittorio Montano Nicola Della Monaca Marco Lauretti Liverana Olivi Alessandro Valentini Valentino Sturiale Carmelo Lucio 《Neurosurgical review》2021,44(1):153-161
Neurosurgical Review - The surgical injury of the intracranial portion of the facial nerve (FN) is a severe complication of many skull base procedures, and it represents a relevant issue in terms... 相似文献
56.
Di Rienzo Alessandro Colasanti Roberto Gladi Maurizio Dobran Mauro Della Costanza Martina Capece Mara Veccia Salvatore Iacoangeli Maurizio 《Neurosurgical review》2021,44(3):1523-1532
Neurosurgical Review - The optimal management of cranioplasty infections remains a matter of debate. Most authors have suggested that the infected bone/implant removal is mandatory, combined with... 相似文献
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59.
Della Corte L Bolam JP Clarke DJ Parry DM Smith AD 《The European journal of neuroscience》1990,2(1):50-61
The autoradiographic localization of radiolabelled taurine taken up in the rat substantia nigra in vivo together with conditions of release of the [3H]taurine taken up into brain slices were studied to determine whether they are consistent with the hypothesis that taurine may act as a neurotransmitter in the striatonigral pathway. At the light microscopic level the main cellular elements that became radiolabelled following the injection of [3H]taurine into the substantia nigra could be identified as glial cells. Electron microscope autoradiography confirmed that a subpopulation of glial cells including astrocytes, pericytes, and oligodendrocytes were radiolabelled and that neuronal perikarya were not radiolabelled. In addition, axonal elements including both terminal and preterminal boutons were found to have silver grains overlying them and were thus considered to be radiolabelled. This was supported by a quantitative analysis of the distribution of the silver grains; whereas glial elements had a significantly higher number of grains associated with them than with any other structure, axonal elements had a significantly greater number of grains than dendritic structures. Release of the preloaded [3H]taurine from superfused slices of substantia nigra occurred in response to veratridine, was calcium-dependent and was sensitive to inhibition by high magnesium concentrations or tetrodotoxin. Following the destruction of neurons in the striatum by ibotenic acid injections, although the weight of the ipsilateral substantia nigra was reduced, the uptake of [3H]taurine was not altered. In contrast to this, the veratridine-stimulated release was markedly attenuated, implying that the destruction of striatal neurons causes the loss of sites in the substantia nigra from which exogenous taurine is released. These results add further support to previous suggestions that taurine might act as a neurotransmitter or neuromodulator in the striatonigral pathway. 相似文献
60.