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61.
Homocysteine and cognitive function in the elderly: the Rotterdam Scan Study   总被引:14,自引:0,他引:14  
BACKGROUND: Elevated plasma total homocysteine (tHcy) concentrations are associated with AD and vascular dementia, but the relation with cognitive performance in nondemented elderly people is not known. OBJECTIVE: To examine the association of tHcy and cognitive function in the elderly, and assess whether this may be mediated by structural brain changes on MRI. METHODS: The Rotterdam Scan Study is a population-based study of 1,077 nondemented elderly. Cognitive performance was assessed, and compound scores were constructed for psychomotor speed, memory function, and global cognitive function. Cerebral infarcts, white matter lesions, and generalized brain atrophy were measured on MRI. The cross-sectional relationship between tHcy levels and neuropsychological test scores was assessed by multiple regression. RESULTS: Mean tHcy level was 11.5 micro mol/L (SD 4.1). Increasing tHcy levels were associated with lower scores for psychomotor speed, memory function, and global cognitive function, and this was largely due to the association with tHcy levels in the upper quintile (>14 micro mol/L). Adjusted differences between test scores of participants in the upper quintile as compared with the lower four quintiles of tHcy were -0.26 (95% CI: -0.37; -0.14) for psychomotor speed, -0.13 (95% CI: -0.27; 0.01) for memory function, and -0.20 (95% CI: -0.30; -0.11) for global cognitive function. These associations were not mediated by structural brain changes on MRI. CONCLUSION: Elevated tHcy levels are associated with decreased cognitive performance in nondemented elderly people, and the relation was most marked for psychomotor speed. This association was independent of structural brain changes on MRI.  相似文献   
62.
OBJECTIVE: To study the relationship between cerebral hemodynamics and clinical performance in normal pressure hydrocephalus (NPH), before and after surgery. MATERIAL AND METHODS: Ten patients were studied prospectively before and 3 months after shunt surgery by means of transcranial Doppler (TCD). Clinical performance was scored by means of an NPH scale and the modified Rankin scale. RESULTS: Peak systolic and mean cerebral blood flow velocity (MCV) were lower and cerebrovascular CO2 reactivity was higher after shunt surgery. The three patients with clinical improvement had higher preoperative end diastolic cerebral blood flow velocity and MCV. All postoperative cerebral blood flow velocities were higher in patients with clinical improvement. CONCLUSION: Our data suggest that higher cerebral blood flow velocity before surgery in patients with NPH is related to clinical improvement after shunt surgery. Cerebral hemodynamic parameters may develop into predictors of successful shunt surgery in patients with normal pressure hydrocephalus.  相似文献   
63.

Background  

Studies on the impact of the 'obesogenic' environment have often used non-theoretical approaches. In this journal's debate and in other papers authors have argued the necessity of formulating conceptual models for differentiating the causal role of environmental influences on behavior.  相似文献   
64.
Long-term results of the lateral tunnel Fontan operation   总被引:11,自引:0,他引:11  
OBJECTIVES: Completion of a total cavopulmonary anastomosis with an intra-atrial lateral tunnel is known to yield good early and midterm results. In this study, we sought to determine the long-term outcome (10 years) after a lateral tunnel Fontan procedure. METHODS: Between October 1987 and December 1991, 220 patients (aged 11 months to 32 years) with a wide range of underlying diagnoses underwent a fenestrated or nonfenestrated lateral tunnel Fontan procedure at our institution. Current follow-up information was available for 196 patients (94%, mean follow-up = 10.2 +/- 0.6 years). Risk factor analysis included patient-related and procedure-related variables, with death, failure, and bradyarrhythmia or tachyarrhythmia as outcome parameters. RESULTS: There were 12 early deaths (<30 days or hospital death), 7 late deaths, 4 successful takedown operations, and 4 heart transplantations. Kaplan-Meier estimated survival was 93% at 5 years and 91% at 10 years, and freedom from failure was 90% at 5 years and 87% at 10 years. Freedom from new supraventricular tachyarrhythmia was 96% at 5 years and 91% at 10 years; freedom from new bradyarrhythmia was 88% at 5 years and 79% at 10 years. Three patients had evidence of protein-losing enteropathy. Multivariable risk factors for development of supraventricular tachyarrhythmia included heterotaxy syndrome, atrioventricular valve abnormalities, and preoperative bradyarrhythmia. Risk factors for bradyarrhythmia included systemic venous anomalies. The sole risk factor for late failure was a previous coarctation repair. CONCLUSION: The lateral tunnel Fontan procedure results in excellent long-term outcome even when used in patients with diverse anatomic diagnoses. The incidence of atrial tachyarrhythmia is low and mainly depends on the underlying cardiac morphology and preoperative arrhythmia. The good long-term outcome after an intracardiac lateral tunnel Fontan procedure should serve as a basis for comparison with other surgical alternatives.  相似文献   
65.

Background  

The objective of this article is to describe the design of a study to evaluate the clinical and economic effects of a Disease Management model on functional health, quality of care and quality of life of persons living in homes for the elderly.  相似文献   
66.
Overheating may cause terminal apnoea and cot death. Rectal temperature and breathing patterns were examined in normal infants at home during the first 6 months of life. Twenty one infants had continuous overnight rectal temperature and breathing recordings for 429 nights (mean 20.4 nights, range 7-30) spaced over the first six months of life. Periods when breathing was 'regular' were directly marked on single night records. Sleep state was determined from respiratory variables. 'Regular' breathing was a reliable marker of 'quiet' sleep (specificity 93%). The duration of 'quiet' sleep increased from 6 to 22 minutes from two weeks to three months of age and then remained static, as did the proportion of sleep spent in the quiet phase (9% to 34%). Rectal temperature fell during 66% of quiet sleep and usually rose during rapid eye movement (REM) sleep. The drop in rectal temperature was maximal at the start of quiet sleep, whereas the maximum rise during REM sleep was reached after 10 to 15 minutes. Oscillations in rectal temperature are associated with changes in sleep and breathing state. The maturation of rectal temperature patterns during the first six months of life are closely related to a maturation of sleep state and breathing patterns.  相似文献   
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69.
A boy with the dysmorphic features of Noonan's syndrome and pulmonary valve stenosis who had evidence of hypoparathyroidism and abnormal T lymphocyte numbers in the neonatal period is reported. He had a normal karyotype but molecular analysis revealed a submicroscopic deletion within chromosome 22q11, the region deleted in DiGeorge syndrome. Thus this child has both Noonan's syndrome and DiGeorge syndrome; 22q11 is a candidate region for a gene defective in Noonan's syndrome.  相似文献   
70.
Seventy-eight children, referred to a diet clinic because of hyperactive behaviour, were placed on a 'few foods' elimination diet. Fifty nine improved in behaviour during this open trial. For 19 of these children it was possible to disguise foods or additives, or both, that reliably provoked behavioural problems by mixing them with other tolerated foods and to test their effect in a placebo controlled double blind challenge protocol. The results of a crossover trial on these 19 children showed a significant effect for the provoking foods to worsen ratings of behaviour and to impair psychological test performance. This study shows that observations of change in behaviour associated with diet made by parents and other people with a role in the child's care can be reproduced using double blind methodology and objective assessments. Clinicians should give weight to the accounts of parents and consider this treatment in selected children with a suggestive medical history.  相似文献   
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