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Pyroglutamic acid (PCA) was compared with placebo in a randomized, double blind trial for assessing its efficacy in treating memory deficits in 40 aged subjects. Twenty subjects were treated with PCA and 20 with placebo over a period of 60 d. Memory functions were evaluated at baseline and after 60 d of treatment by means of a battery made up of 6 memory tasks. The results suggest that PCA is effective in improving some verbal memory functions in subjects affected by age-related memory decline.  相似文献   
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In order to quantify presence of residual BCC in patients with histologic positive margins after the first excison and to correlate the presence of residual tumor in re‐excised lesions with the location of the positive margin on the first excision, a retrospective evaluation of 2053 surgically treated BCC was performed. Only 38.3% of the re‐excised lesions showed residual tumor. In the group of re‐excised lesions where residual BCC was found, 13% had lateral positive margin in the first excision, 39% had deep positive margin and 48% had both lateral and deep positive margins. In the group of re‐excised lesions where no residual BCC was found, 49% of the primary excised lesions had lateral positive margin, 32% had deep positive margin and 19% had both deep and lateral positive margins. The association between residual tumor and positive margins was statistically significant (p = 0.01). Our findings confirm that presence of residual tumour is more likely when both lateral and deep margins are compromised.  相似文献   
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OBJECTIVE: To test the hypothesis that perfluorocarbon (PFC) priming before surfactant administration improves gas exchange and lung compliance, and also decreases lung injury, more than surfactant alone. DESIGN: Prospective, randomized animal study. SETTING: Animal research laboratory of Children's Hospital of St. Paul. SUBJECTS: Thirty-two newborn piglets, weighing 1.55 +/- 0.18 kg. INTERVENTIONS: We studied four groups of eight animals randomized after anesthesia, paralysis, tracheostomy, and establishment of lung injury using saline washout to receive one of the following treatments: a) surfactant alone (n = 8); b) priming with the PFC perflubron alone (n = 8); c) priming with perflubron followed by surfactant (n = 8); and d) no treatment (control; n = 8). Perflubron priming was achieved by instilling perflubron via the endotracheal tube in an amount estimated to represent the functional residual capacity, ventilating the animal for 30 mins, and then removing perflubron by suctioning. After all treatments were given, animals were mechanically ventilated for 4 hrs. MEASUREMENTS AND MAIN RESULTS: We evaluated oxygenation, airway pressures, respiratory system compliance, and hemodynamics at baseline, after induction of lung injury, and at 30-min intervals for 4 hrs. Histopathologic evaluation was carried out using a semiquantitative scoring system and by computer-assisted morphometric analysis. After all treatments, animals had decreased oxygenation indices (p < .001) and increased respiratory system compliance (p < .05). Animals in PFC groups had similar physiologic responses to treatments as animals treated with surfactant only; both the PFC-treated groups and the surfactant-treated animals required lower mean airway pressures throughout the experiment (p < .001) and had higher pH levels at 90 and 120 mins (p < .05) compared with the control group. Pathologic analysis demonstrated decreased lung injury in surfactant-treated animals compared with animals treated with PFC or the controls (p < .02). CONCLUSIONS: Priming the lung with PFC neither improved the physiologic effects of exogenous surfactant nor improved lung pathology in this animal model.  相似文献   
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