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The human visual system is amenable to a number of adaptive processes; one such process, or collection of processes, is the adaptation to blur. Blur adaptation can be observed as an improvement in vision under degraded conditions, and these changes occur relatively rapidly following exposure to blur. The potential important future directions of this research area and the clinical implications of blur adaptation are discussed.  相似文献   
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We surveyed 655 health professionals affiliated with tertiary level neonatal intensive care units in Canada and the United States to define an expanded role for nurses in neonatology and to determine the educational requirements for the role. The role, comprising advanced clinical practice, educational, research, and administrative responsibilities, is a blend of nurse practitioner and clinical nurse specialist activities. Based on survey findings, a neonatal stream within the existing Master of Health Sciences program at McMaster University was developed. To date, 15 clinical nurse specialists/neonatal practitioners (CNS/NPs) are employed in five neonatal intensive care units in Ontario and other related institutions. A randomized trial to evaluate these individuals is in progress.  相似文献   
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High serum fluoride (F-) in patients with chronic renal failure (CRF) and end-stage renal disease (ESRD) is associated with risk of renal osteodystrophy and other bone changes. This study was done to determine F- in normal healthy controls and patients with ESRD on haemodialysis (HD) or peritoneal dialysis (PD). Seventeen healthy controls (12 males, 5 females) and 39 ESRD patients on dialysis (17 males, 22 females) were recruited in the study in a community with 47.4 +/- 3.28 microM/l (range 44-51 microM/l) of F- content in drinking water. Control subjects showed a mean serum F- concentration of 1.08 +/- 0.350 microM/l. Males in control group showed slightly higher F- levels (1.15 +/- 0.334, range 0.55-1.9 microM/l) than females (0.92 +/- 0.370, range 0.6-1.5 microM/l). Mean serum F- concentration did not correlate significantly with age and sex among control subjects, whereas such correlation was observed in patients with ESRD on dialysis. Mean serum F- concentration was significantly higher in patients on dialysis (2.67 +/- 1.09, range 0.8-5.2 microM/l) than normal controls. When grouped according to sex, the mean serum F- concentration in males (3.05 +/- 1.04, range 1.8-5.2 microM/l) was significantly higher than females (2.38 +/- 1.08, range 0.8-5.2 microM/l). When patients were grouped according to age, it was observed that F- concentration was significantly higher in patients with age groups 21-70 (2.86 +/- 1.05) than those with age group 13-20 years (1.42 +/- 0.531). Thus F- concentration correlated with age and sex, being higher in males and above 20 years. Despite appreciable clearance of F- (39-90%) across the peritoneum, patients on CAPD showed higher serum F- concentration than those on HD (3.1 +/- 1.97 vs 2.5 +/- 1.137 microM/l). Of the total 39 patients on dialysis 39% had their serum F- concentration above 3.0 microM/l, posing the risk of renal osteodystrophy.   相似文献   
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OBJECTIVE: The aim of this work was to study cytokeratin (Ck) expression in initial radiation-induced oral mucositis. STUDY DESIGN: Eleven cases of initial radiomucositis of the buccal mucosa and 9 normal specimens were immunostained for Ck 1, 5, 6, 7, 8, 10, 14, 16, 18, and 19 by immunoperoxidase method. RESULTS: Expression of Ck 1, 6, 10, and 16 was stronger in mucositis than in normal mucosa. Ck 7, 8, and 18 were negative for both control and study groups. Ck 5, 13, and 14 were positive for both groups, nevertheless suprabasal staining for Ck 14 was more evident in mucositis than in the control group. Sporadic staining for Ck 19 was observed in 1 case of mucositis and in 2 controls. CONCLUSIONS: Increased Ck expression can be associated with the reactive proliferation of the epithelium and increasing resistance of the oral mucosa during the initial phases of radiotherapy.  相似文献   
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Metabolic adaptation of the chick embryo to chronic hypoxia   总被引:1,自引:0,他引:1  
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