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Tibial plateau fractures are complex injuries which, if not adequately treated, can lead to invalidating sequelae. They constitute on average about 1% of all fractures, and up to 8% in patients over 65 years, and can be caused by both high- and low-energy trauma. Unlike in younger subjects, treatment of tibial plateau fractures in the elderly is not univocal and depends on the patient’s functional needs, bone quality and systemic comorbidities. In this retrospective study, 49 patients with a mean age of 72 years, who underwent surgical treatment of a tibial plateau fracture, were assessed by the Rasmussen’s clinical and radiological grading systems. Clinical and radiographic outcomes were satisfactory in 75.5 and 59.1% of cases, respectively. Data were also analyzed, in terms of fracture type, age and gender, to detect any statistically significant correlation between these parameters and clinical and radiographic outcomes.  相似文献   
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To analyse the effect of concomitant cognitive or motor task performance on balance control in Parkinson's disease (PD), we performed a posturographic study in 24 PD patients and in 20 sex- and age-matched control subjects. Postural sway was measured with eyes open (EO) and eyes closed (EC) during quiet stance and during performance of calculation or motor sequence of thumb opposition to the other fingers. No difference of centre of foot pressure (COP) parameters was observed during quiet standing (either EO or EC) between patients and controls, but visual deprivation induced in both groups a worsening of postural stability. COP area was significantly increased in PD patients during dual task performance, whereas no difference of COP path and x-y axes was observed. The effects induced by the performance of cognitive or motor task were significantly more evident in PD patients with clinical evidence of postural instability (presence of prior falls in the history). This study demonstrates that dual task interference on postural control can be observed in PD patients during performance of cognitive as well as motor tasks. The balance deterioration during dual task performance was significantly enhanced in patients with history of prior falls. These findings have some implications for the strategies to be used in reducing the risk of fall in PD.  相似文献   
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Serum immunoglobulins and the activity of natural killer (NK) cells of 50 epileptic patients (eight with idiopathic generalized epilepsy and 42 with cryptogenic partial epilepsy) and 28 controls have been studied. The values of IgA, IgG and IgM were the same-in patients and controls. The NK activity in controls was linearly related to the effector-to-target ratio, but this linear relationship was not observed in epileptic patients. The cytotoxic activity of NK cells at the lowest effector-to-target ratio was significantly greater in patients than in controls. This increase was observed in each therapy group. Our results seem to confirm a disturbance of the immune system in epileptic patients and suggest that this modification of cellular immunity is not a drug effect but is related to the illness itself.  相似文献   
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OBJECTIVE: The purpose of this study was to retrospectively evaluate leucite-reinforced glass-ceramic crowns placed over a 6-year period at two different private dental practices. METHOD AND MATERIALS: One hundred twenty-five Empress crowns were placed in 54 patients. The 93 anterior and 32 posterior crowns were evaluated clinically with a mirror and probe, radiographically, and from clinical photographs, in accordance with a modified California Dental Association and Ryge quality evaluation system. The risk of fracture was determined with the Kaplan-Meier survival analysis. RESULTS: Crowns were studied over periods ranging from 4 to 11 years. The probability of survival of the 125 crowns was 95.2% at 11 years (98.9% in the anterior segment and 84.4% in the posterior segment). Six crowns had to be replaced. Most of the 119 successful crowns were rated excellent; Alfa ratings were assigned to 94.2% for color match, 91.6% for porcelain surface, 86.6% for marginal discoloration, and 94.2% for marginal integrity. CONCLUSION: Leucite-reinforced glass-ceramic crowns showed a low clinical failure rate and excellent esthetics after up to 11 years.  相似文献   
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A series of 21 neuroleptics with different chemical structures (phenothiazines, thioxanthenes, dibenzodiazepines, butyrophenones, benzamides, etc.) was examined for their in vitro interactions with 12 neurotransmitter binding sites in the rat brain (alpha- and beta-noradrenergic, dopaminergic, muscarinic, serotoninergic, histaminic, and opioid receptors, calcium channels, and serotonin uptake binding sites). The biochemical profile obtained from the binding data was compared with reported pharmacological and clinical profiles for this class of compounds by cluster analysis. Cluster analysis on binding data classified the compounds in three main subgroups: benzamides, compounds with an affinity mainly for DA2 and 5-HT2 receptors and inactive at muscarinic receptors, and compounds with a high affinity for alpha 1-adrenergic receptors and muscarinic receptors. The main subgroups resulting from cluster analysis of previously published pharmacological and clinical data for neuroleptics contain compounds common to the present study, with some correlations. The results extend previous observations that a complete binding profile corresponds to the pharmacological and clinical profile of this class of compounds.  相似文献   
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