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1.
Nondemented older adults genotyped for the Apolipoprotein E (ApoE) ε4 allele (n?=?43) were neuropsychologically compared to participants without a copy of the ε4 allele (n?=?90). At baseline, the groups did not differ on age, education, gender, or global cognitive status. ApoE-ε4 participants demonstrated significantly poorer mean performances on delayed recall, but no significant group differences emerged on attention, language, constructional skills, psychomotor speed, or executive function. Significantly more ApoE-ε4 participants developed probable or questionable Alzheimer's disease (AD) compared with non-ε4 participants, suggesting that the group differences resulted from a preponderance of preclinical AD cases within the ε4 group and not from a direct influence of ApoE genotype on cognition. Cox proportional hazards analysis, adjusting for age, years of education, and global cognitive status, revealed that ApoE-ε4 allele status and measures of recall performance were significant and independent predictors of conversion to AD. Results support the importance of specific episodic memory changes and possession of the ApoE-ε4 allele in the preclinical detection of AD. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

2.
OBJECTIVE: To identify risk factors for and functional consequences of lacunar infarct in elderly people. METHODS: The Cardiovascular Health Study (CHS) is a longitudinal study of people 65 years or older, in which 3660 participants underwent cranial magnetic resonance imaging (MRI). Neuroradiologists read scans in a standard fashion without any clinical information. Lacunes were defined as subcortical areas consistent with infarcts measuring 3 to 20 mm. In cross-sectional analyses, clinical correlates were contrasted among groups defined by MRI findings. RESULTS: Of the 3660 subjects who underwent MRI, 2529 (69%) were free of infarcts of any kind and 841 (23%) had 1 or more lacunes without other types present, totaling 1270 lacunes. For most of these 841 subjects, their lacunes were single (66%) and silent (89%), namely without a history of transient ischemic attack or stroke. In multivariate analyses, factors independently associated with lacunes were increased age, diastolic blood pressure, creatinine, and pack-years of smoking (listed in descending order of strength of association; for all, P < .005), as well as maximum internal carotid artery stenosis of more than 50% (odds ratio [OR], 1.81; P < .005), male sex (OR, 0.74; P < .005), and history of diabetes at entrance into the study (OR, 1.33; P < .05). Models for subgroups of single, multiple, silent, and symptomatic lacunes differed only minimally. Those with silent lacunes had more cognitive, upper extremity, and lower extremity dysfunction not recognized as stroke than those whose MRIs were free of infarcts. CONCLUSIONS: In this group of older adults, lacunes defined by MRI are common and associated with factors that likely promote or reflect small-vessel disease. Silent lacunes are also associated with neurologic dysfunction.  相似文献   

3.
OBJECTIVE: To identify independent predictors of intracranial hemorrhage (ICH) during neonatal extracorporeal membrane oxygenation (ECMO). STUDY DESIGN: This retrospective cohort consisted of all neonates who did not have an ICH before treatment with ECMO identified in the Extracorporeal Life Support Organization Registry from 1992 to 1995 (n = 4550). Multiple logistic regression analysis was used to identify factors independently correlated with ICH and to develop a model that could be used to predict the risk of ICH in neonates treated with ECMO. RESULTS: ICH was identified in 9.9% of patients. The factors associated with ICH remaining after adjusting for other significant variables (P <.01) were gestational age (GA) <34 weeks (odds ratio [OR] 12.1, 95% confidence intervals [CI] [6.6, 22]), GA 34 to <36 weeks (OR 4.1, CI [2.9, 5.8]), GA 36 to <38 weeks (OR 2.1, CI [1.6, 2.8]) primary diagnosis of sepsis (OR 1.8, CI [1.4, 2.3]), epinephrine use (OR 1.9, CI [1.5, 2.5]), coagulopathy (OR 1. 6, CI [1.1, 2.2]), arterial pH <7.0 (OR 2.5, CI [1.6, 3.9]), and arterial pH 7.0 to <7.2 (OR 1.8 CI [1.3, 2.5]). ICH rates for neonates receiving venovenous versus venoarterial ECMO and for those treated with or without cephalic jugular venous drainage were not significantly different. CONCLUSIONS: Gestational age, acidosis, sepsis, coagulopathy, and treatment with epinephrine are major independent factors associated with ICH in neonates treated with ECMO. In particular, GA <34 weeks remains a major barrier for use of current ECMO technologies.  相似文献   

4.
BACKGROUND AND PURPOSE: Previous studies have suggested that recovery of cognitive function after stroke is maximal within the first 3 months after onset. We performed the present study to investigate the long-term course and clinical correlates of improvement in generalized cognitive function after ischemic stroke. METHODS: We administered a battery of neuropsychological tests to 151 patients (age, 70.4 +/- 7.7 years; education, 10.4 +/- 4.6 years) at 3 months and then annually after stroke. We transformed their test results into z scores based on the performance of a stroke-free normative group, averaged those scores to create a summary score, and defined improvement in annual examinations as an increase in that summary score greater than two standard deviations above the mean first annual change of the normative group. We then used logistic regression to determine whether stroke location, syndrome, or recurrence; vascular risk factors; dementia status; depression; or demographic variables were associated with improvement. RESULTS: We found that 19 of the 151 patients exhibited improvement, which was evident only at the first annual examination in most cases. Logistic regression determined that improvement was significantly related to left hemisphere infarction relative to brain stem/cerebellar infarction (odds ratio [OR], 5.57), while the presence of a major hemispheral stroke syndrome showed a trend toward significance (OR, 3.32). Diabetes mellitus was significantly associated with a failure to exhibit improvement (OR, 0.12). Based on the logistic model, the probability of long-term improvement would be 54.0% for a patient with a left hemisphere infarct and a major hemispheral syndrome but only 11.9% if diabetes was also present. CONCLUSIONS: Long-term improvement in generalized cognitive function may be evident after stroke in association with left hemisphere infarction and severe hemispheral syndromes, while it may be compromised by diabetes, possibly because of an increased burden of cerebrovascular disease.  相似文献   

5.
OBJECTIVE: To study pregnancy outcomes among teenagers and to determine whether age-related increases in risk are due to differences in socioeconomic conditions, maternal smoking, or anthropometric status. METHODS: All single births during 1990-1991 to mothers aged less than 25 years recorded in the Swedish Medical Birth Registry were studied (n = 62,433). The pregnancy outcomes analyzed were late fetal death, infant mortality, preterm birth, low birth weight, small for gestational age, and low Apgar scores. Information on maternal age, parity, family situation, maternal smoking, maternal height, and weight gain during pregnancy was recorded in the Medical Birth Registry. Information on socioeconomic characteristics was obtained from the Population Census. Logistic regression analysis was used to define the determinants of the adverse outcomes among teenagers. RESULTS: Compared with women aged 20-24 years, girls of 17 years or less were at higher risk for preterm birth (odds ratio [OR] 1.6), and this increased risk remained essentially unchanged after controlling for major confounding factors (OR 1.5). Teenagers also had a crude 50% higher risk of late fetal death and infant mortality, but this risk was reduced after controlling for the effect of socioeconomic characteristics (adjusted OR 1.2). CONCLUSIONS: The increase in risk of late fetal death and infant mortality associated with low maternal age is substantially an effect of teenagers' poorer socioeconomic situation. However, the increase in preterm birth among younger teenagers suggests that young maternal age may be a biologic risk factor for preterm birth.  相似文献   

6.
In the Abecedarian Project, a prospective randomized trial, the effects of early educational intervention on patterns of cognitive and academic development among poor, minority children were examined. Participants in the follow-up were 104 of the original 111 participants in the study (98% African American). Early treatment was full-time, high-quality, educational child care from infancy to age 5. Cognitive test scores collected between the ages of 3 and 21 years and academic test scores from 8 to 21 years were analyzed. Treated children, on average, attained higher scores on both cognitive and academic tests, with moderate to large treatment effect sizes observed through age 21. Preschool cognitive gains accounted for a substantial portion of treatment differences in the development of reading and math skills. Intensive early childhood education can have long-lasting effects on cognitive and academic development. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

7.
To examine the correlates of dependent living after ischemic stroke, a consecutive cohort of 486 patients aged 55-85 years was examined 3 months after the index stroke. Detailed medical, neurological and radiological stroke evaluation, structured measures of cognition, emotion and behavior, activities of daily living (ADL), physical disability, and assessment of dependent living were performed. Independent correlates of dependent living 3 months after stroke were the presence of the major hemispheral stroke syndrome (odds ratio, OR, 11.8, 95% confidence interval, CI, 7.2-19.9), and a combination of handicap (Rankin Scale, OR 3.9, 95% CI 2.6-6.1), cognition (DSM-III-R dementia, OR 3.9, CI 1.5-10.7, any cognitive decline, OR 4.5, CI 2.0-11.2), and ADL [Functional Activities Questionnaire (FAQ), OR 1.2, 95% CI 1.1-1.2]. The Rankin Scale explained 51.5%, FAQ 5.9% and presence of DSM-III-R dementia or any cognitive decline 3.4% of the total variance between dependent and independent patients after stroke. Independent of the effects of physical disability, presence of cognitive impairment has important functional consequences on stroke patients. Our findings emphasize the importance of the evaluation of cognitive functions in both observational and interventional clinical trials, as well as in treatment planning, rehabilitation and guidance of patients with ischemic stroke.  相似文献   

8.
OBJECTIVE: To determine the prevalence and causes of pleural effusions in patients admitted to a medical ICU (MICU). DESIGN: Prospective. SETTING: MICU in a tertiary care hospital. PATIENTS: One hundred consecutive patients admitted to the MICU at the Medical University of South Carolina whose length of stay exceeded 24 h had chest radiographs reviewed daily and chest sonograms performed within 10 h of their latest chest radiograph. RESULTS: The prevalence of pleural effusions in 100 consecutive MICU patients was 62%, with 41% of effusions detected at admission. Fifty-seven of 62 (92%) pleural effusions were small. Causes of pleural effusions were as follows: heart failure, 22 of 62 (35%); atelectasis, 14 of 62 (23%); uncomplicated parapneumonic effusions, seven of 62 (11%); hepatic hydrothorax, five of 62 (8%); hypoalbuminemia, five of 62 (8%); malignancy, two of 62 (3%); and unknown, three of 62 (5%). Pancreatitis, extravascular catheter migration, uremic pleurisy, and empyema caused an effusion in one instance each. Heart failure was the most frequent cause of bilateral effusions (13/34 [38%]). When compared with patients who never had effusions during their MICU stay, patients with pleural effusions were older (54+/-2 years, mean+/-SEM, vs 47+/-2 years [p=0.04]), had lower serum albumin concentration (2.4+/-0.1 vs 3.0+/-0.01 g/dL [p=0.002]), higher acute physiology and chronic health evaluation II scores during the initial 24 h of MICU stay (17.2+/-1.1 vs 12+/-1.2 [p=0.010]), longer MICU stays (9.8+/-1.0 vs 4.6+/-0.7 days [p=0.0002]), and longer mechanical ventilation (7.0+/-1.3 vs 1.9+/-0.7 days [p=0.004]). No patient died as a direct result of his or her pleural effusion. Chest radiograph readings had good correlation with chest sonograms (p<0.0001). CONCLUSION: Pleural effusions in MICU patients are common, and most are detected by careful review of chest radiographs taken with the patient in erect or semierect position. When clinical suspicion for infection is low, observation of these effusions is warranted initially, because most are caused by noninfectious processes that should improve with treatment of the underlying disease.  相似文献   

9.
Previous research has shown that asymmetry of brain activity is decreased in older adults. This study investigates whether cortical gray matter asymmetry also shows age-related differences, and whether gray matter asymmetry differs between cognitively stable persons and persons who have shown profound age-related declines in cognitive functioning. In addition, we have examined whether prodromal dementia affects the study outcome. The gray matter volumes of seven prefrontal and temporal regions of interest were delineated on T1-weighted MRI scans in 70 adults aged between 52 and 84 years. Statistical analyses were conducted with and without participants who developed dementia within 6 years after the MRI scan session. It was found that asymmetry did not differ over the age range of 52–84 years of age. This result did not change when data from participants who were diagnosed with dementia within 6 years after MRI assessment were excluded from the analysis. In addition, no gray matter asymmetry differences were found between cognitively stable participants and participants who showed cognitive decline. We conclude that alterations in gray matter asymmetry may not be part of the healthy aging process. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

10.
PURPOSE: To evaluate the prognostic value of anemia in squamous cell carcinomas in the head and neck treated with curative radiation therapy alone. MATERIALS AND METHODS: In a prospective study, the hemoglobin level was measured prior to radiation therapy in 217 patients (188 [87%] men and 29 [13%] women) with cancer of the oral cavity (n = 61 [28%]), oropharynx (n = 53 [24%]), hypopharynx (n = 21 [10%]), and larynx (n = 82 [38%]). Anemia, defined as hemoglobin level below 13.5 g/dL in men and below 12.0 g/dL in women, was diagnosed in 58 (31%) of the men and five (17%) of the women. Median follow-up was 29 months (range, 2-63 months). RESULTS: The 2-year actuarial probability of local-regional control was 69% (95% confidence interval, 63%, 76%). Multivariate analysis showed the relative risk of failure of local-regional control to increase for stage T3 and T4 tumors (1.8 [95% confidence interval, 1.1, 3.1]), stage N3 nodes (3.6 [95% confidence interval, 1.8, 7.1]), weight loss (2.2 [95% confidence interval, 1.3, 4.0]), and anemia (1.6 [95% confidence interval, 1.0-2.7]). The relative risk of death increased for stage T3 and T4 tumors (2.5 [95% confidence interval, 1.4, 4.3]), N3 nodes (4.0 [95% confidence interval, 1.0, 7.9]), oral cavity tumors (2.0 [95% confidence interval, 1.2, 3.2]), male sex (4.1 [95% confidence interval, 1.3, 13.1]), weight loss (2.2 [95% confidence interval, 1.3, 3.7]), and anemia (1.7 [95% confidence interval, 1.03, 2.7]). CONCLUSION: Moderate anemia appeared to be an independent prognostic factor in squamous cell carcinoma of the head and neck treated with radiation therapy alone.  相似文献   

11.
BACKGROUND: The purpose of this study was to analyse which lifestyle parameters (daily physical activity, dietary intake, smoking habits and alcohol consumption) discriminate between participants at high-risk and those at low-risk for coronary heart disease (CHD) [systolic and diastolic blood pressure (SBP/DBP), total serum cholesterol (TC), high-density lipoprotein cholesterol (HDL), the TC: HDL ratio, body fatness (sum of skinfolds [SSF]) and cardiopulmonary fitness (VO2-max)]. METHODS: The data were derived from the Amsterdam Growth and Health Study (AGHS); an observational longitudinal study in which six repeated measurements were carried out over a period of 15 years on 181 participants aged 13 years at entry to the study. To assess possible discriminating factors, generalized estimating equations were used. This method makes use of risk group changing behaviour over time by using all available longitudinal data. RESULTS: For DBP no significant relationships were found; high risk for SBP was inversely related to smoking habits (OR=0.52; P<0.01). No significant relationships were found for TC; high risk for HDL was positively related to the intake of carbohydrates (OR=1.2; P=0.02) and to smoking habits (OR=1.6; P=0.04); high risk for the TC:HDL ratio was positively related to the intake of carbohydrates (OR=1.3; P=0.01). High risk for SSF was positively related to the intake of protein (OR=1.5; P<0.01) and smoking habits (OR=1.8; P=0.01) and inversely related to daily physical activity (OR=0.81; P=0.01). High risk for VO2-max was inversely related to daily physical activity (OR=0.67; P<0.01). CONCLUSIONS: In the relative young and healthy population of the AGHS during adolescence and young adulthood, physical inactivity was the most important lifestyle parameter related to high risk for CHD.  相似文献   

12.
The objective of this study was to investigate the relation between the peripheral concentrations of the adrenal steroid hormones cortisol and dehydroepiandrosterone sulfate (DHEAS) and cognitive impairment and decline. A prospective study design was used. The setting was a suburb of Rotterdam, The Netherlands. The study population consisted of a sample of 189 healthy participants from the population-based Rotterdam Study, aged 55-80 yr, who were invited for an additional examination. Follow-up examinations took place 1.9 yr after baseline, on the average. We determined fasting blood levels of DHEAS before dexamethasone administration and of cortisol and corticosteroid-binding globulin before and after the administration of 1 mg dexamethasone overnight. The 30-point Mini-Mental State Examination (MMSE) was used to assess cognition. The associations with cognitive impairment (MMSE score of <26; 6% of the sample) and cognitive decline (drop in MMSE score of >1 point/yr; 24%) were estimated using logistic regression, with adjustment for age, sex, education, and depressive symptoms. An increase of 1 SD in the estimate of free cortisol (SD = 30.3) was associated with cognitive impairment, although not significantly [odds ratio (OR) = 1.5; 95% confidence interval (CI), 0.9-2.4]. A 1 SD increase in the natural logarithm of cortisol after the administration of 1 mg dexamethasone (SD = 0.68) was associated with an OR for cognitive decline of 1.5 (95% CI, 1.0-2.3). A 1 SD increase in DHEAS (SD = 2.10 micromol/L) was inversely, but nonsignificantly, related to cognitive impairment (OR = 0.5; 95% CI, 0.2-1.1) and cognitive decline (OR = 0.6; 95% CI, 0.4-1.1). The ratio of free cortisol over DHEAS was significantly related to cognitive impairment (OR = 1.8; 95% CI, 1.0-3.2). This prospective study among healthy elderly subjects suggested that basal free cortisol levels were positively related to cognitive impairment, and cortisol levels after dexamethasone treatment were related to cognitive decline. There was an inverse, but nonsignificant, association between DHEAS and cognitive impairment and decline.  相似文献   

13.
OBJECTIVE: To determine the relationship of brain infarction to the clinical expression of Alzheimer disease (AD). DESIGN: Cognitive function and the prevalence of dementia were determined for participants in the Nun Study who later died. At autopsy, lacunar and larger brain infarcts were identified, and senile plaques and neurofibrillary tangles in the neocortex were quantitated. Participants with abundant senile plaques and some neurofibrillary tangles in the neocortex were classified as having met the neuropathologic criteria for AD. SETTING: Convents in the Midwestern, Eastern, and Southern United States. PARTICIPANTS: A total of 102 college-educated women aged 76 to 100 years. MAIN OUTCOME MEASURES: Cognitive function assessed by standard tests and dementia and AD assessed by clinical and neuropathologic criteria. RESULTS: Among 61 participants who met the neuropathologic criteria for AD, those with brain infarcts had poorer cognitive function and a higher prevalence of dementia than those without infarcts. Participants with lacunar infarcts in the basal ganglia, thalamus, or deep white matter had an especially high prevalence of dementia, compared with those without infarcts (the odds ratio [OR] for dementia was 20.7, 95% confidence interval [95% CI], 1.5-288.0). Fewer neuropathologic lesions of AD appeared to result in dementia in those with lacunar infarcts in the basal ganglia, thalamus, or deep white matter than in those without infarcts. In contrast, among 41 participants who did not meet the neuropathologic criteria for AD, brain infarcts were only weakly associated with poor cognitive function and dementia. Among all 102 participants, atherosclerosis of the circle of Willis was strongly associated with lacunar and large brain infarcts. CONCLUSION: These findings suggest that cerebrovascular disease may play an important role in determining the presence and severity of the clinical symptoms of AD.  相似文献   

14.
MRI scans measured white matter lesion prevalence (WMLP) in 65 people ages 65-84 years who also took 17 cognitive tests: 3 tests of general fluid intelligence, 3 of vocabulary, 2 of episodic and 3 of working memory, 2 of processing speed, and 4 of frontal and executive function. Entry of age with WMLP into regression equations as predictors of test scores showed that inferences about the functional relationships between markers of brain aging and cognitive impairments are seriously misleading if they are based on simple correlations alone. A new finding that WMLP accounts for all of the age-related variance between individuals in tests of speed and executive ability but for none of the age-related variance in intelligence revises current hypotheses that gross brain changes affect general fluid intelligence and other mental abilities solely through their effects on information-processing speed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

15.
OBJECTIVE: To assess the correlation between cognitive dysfunction and disease burden in multiple sclerosis (MS) during a 1-year period. DESIGN: The Brief, Repeatable Battery of Neuropsychological Tests in Multiple Sclerosis was performed at entrance and 1 year. Patients underwent at least 20 proton density (range, 20-24) and T2-weighted axial magnetic resonance imaging (MRI) brain scans except for stable patients who were scanned monthly. Magnetic resonance imaging was evaluated using computer-automated, 3-dimensional volumetric analysis. SETTING: A research clinic of a university hospital. PATIENTS: Forty-four patients with MS of the following disease categories: relapsing-remitting (14), relapsing-remitting progressive (12), chronic progressive (13), and stable (5). MAIN OUTCOME MEASURES: The relationships between scores on the Brief, Repeatable Battery of Neuropsychological Tests in Multiple Sclerosis and 2 MRI measures (total lesion volume and brain to intracranial cavity volume ratio) were assessed using linear regression. These MRI measures were also compared with cognitive status at 1 year using analysis of variance. RESULTS: Overall, there was no decline in mean cognitive test performance during 1 year. Significant correlations were found between baseline neuropsychological test scores of nonverbal memory, information-processing speed, and attention and both MRI measures. Patients with chronic progressive MS demonstrated the strongest correlations. At 1 year, change in information-processing speed and attention correlated with change in total lesion volume. The mean increase in total lesion volume was 5.7 mL for 4 patients whose cognitive status worsened compared with 0.4 mL for 19 patients who improved and 0.5 mL for 21 patients who remained stable. CONCLUSIONS: During a 1-year period mean cognitive performance did not worsen. Automated volumetric MRI measures of total lesion volume and brain to intracranial cavity volume ratio correlated with neuropsychological performance, especially in patients with chronic progressive MS. Worsening MRI lesion burden correlated with cognitive decline.  相似文献   

16.
OBJECTIVE: To determine the association between serum estrogen levels, cognitive performance, and risk of cognitive decline in older women. DESIGN: Prospective cohort study with an average follow-up of 5 years. SETTING: Clinical centers in Baltimore, MD, Minneapolis, MN, Portland, OR, and the Monongahela Valley in Pennsylvania. PARTICIPANTS: 532 women aged 65 years or older who were the controls from two nested case-control studies in the ongoing Study of Osteoporotic Fractures. OUTCOME MEASURES: Three cognitive tests--a modified Mini-Mental Status Exam, Digit Symbol, and Trails B--were administered at study initiation and were then repeated approximately 5 years later. Estrone and estradiol levels were determined by radioimmunoassay at two laboratories from baseline stored serum. RESULTS: The characteristics of the women in the four serum estrogen quartiles did not differ except that body weight and change in weight since age 50 increased directly with higher quartile of serum estrogen (P < .001, for both estrone and estradiol). Initial cognitive performance on all three tests did not differ consistently by quartile of estradiol or by the estradiol to estrone ratio. Women in the higher estrone quartiles had 15% lower (worse) scores on Digit Symbol compared with the lower quartiles (P=.004) but there was no difference by quartile on the modified MMSE or on Trails B. Cognitive function test scores declined over the 5 years of follow-up. There was no difference in amount of change by quartile of estradiol, but women in the higher estrone quartiles had greater reduction of scores on Trails B compared with those in the lower quartiles (P=.012), even after adjusting for age, education, depression, stroke history, weight, and change in weight since age 50. The age-adjusted odds of cognitive decline (defined as tenth percentile of women with the largest decline in cognitive performance) did not vary across quartile of estrone or estradiol. CONCLUSIONS: Endogenous estrogens are not associated consistently with cognitive performance or risk of cognitive decline on a selected battery of cognitive tests in older community-dwelling women. Worse performance on two cognitive tests among women with higher estrone levels was surprising and warrants further investigation.  相似文献   

17.
This study examined how age and education influence the relationship between neuropsychological test scores and brain structure in demographically diverse older adults spanning the range from normal cognition to dementia. A sample of 351 African Americans, 410 Hispanics, and 458 Whites underwent neuropsychological testing. Volumetric magnetic resonance imaging (MRI) measures of total brain, white matter hyperintensity, and hippocampus were available for 79 African Americans, 102 Hispanics, and 134 Whites. The authors used latent variable modeling to examine effects of age, education, and brain volumes on test scores and determine how much variance brain volumes explained in unadjusted and age- and education-adjusted scores. Age adjustment resulted in weaker relationships of test scores with MRI variables; adjustment for ethnicity yielded stronger relationships. Education adjustment increased relationships with MRI variables in the combined sample and Hispanics, made no difference in Whites, but decreased some associations in African Americans. Results suggest that demographic adjustment is beneficial when demographic variables are strongly related to test scores independent of measures of brain structure, but adjustment has negative consequences when effects of demographic characteristics are mediated by brain structure. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

18.
BACKGROUND: This study was designed to determine the prognostic value of positive surgical resection margin or highest nodal station sampled at thoracotomy in patients with non-small cell lung cancer. METHODS: Two reviewers independently examined the surgical records and pathologic reports from a randomized trial comparing computed tomography versus mediastinoscopy for staging of lung cancer. They recorded pathologic findings at the surgical resection margin, the highest mediastinal nodal station sampled at thoracotomy, histologic type, tumor size, N status, and evidence of vascular or lymphatic invasion. These variables formed the independent variables in logistic regression models to predict recurrence. RESULTS: Except for 1 patient, follow-up at 3 years for 399 included patients was complete. Significant predictors of recurrence were tumor size (odds ratio [OR], 1.2 (per centimeter); 99% CI [confidence interval], 1.1 to 1.4), and N status (compared with N0, N1: OR, 1.6; CI, 0.8 to 3.1; N2: OR, 3.2; CI, 1.4 to 7.5). Other variables, including positive surgical resection margin, did not predict early recurrence or death. CONCLUSIONS: In patients with non-small cell lung cancer, surgical resection margin or highest nodal station sampled at thoracotomy that are involved by carcinoma do not predict recurrence. The current definition of incomplete resection has limited prognostic significance.  相似文献   

19.
OBJECTIVE: This study correlated the extent of abnormalities detected by different magnetic resonance imaging (MRI) techniques [proton density (PD)-weighted, T1-weighted, and magnetization transfer imaging (MTI)] with the overall cognitive, frontal lobe, and memory impairments in patients with MS. PATIENTS: There were 30 clinically definite MS patients, with different disease courses. Exclusion criteria: psychoactive/steroid treatments, mood disorders, acute relapse phase. MAIN OUTCOME MEASURES: Neuropsychological test results. Total (TLL) and frontal (FLL) lesion loads assessed from PD-weighted, T1-weighted (22 patients), and MTI (22 patients) MRI scans. Average lesion MT ratios (MTR) and analysis of the MTR histograms from brain tissue axial slabs on MTI scans. RESULTS: Patients with frontal lobe deficits (n=15) or memory impairment (n-17) had a higher TLL on PD scans (p=0.04 and p=0.01, respectively). Patients with frontal lobe deficits had higher FLL on PD scans (p=0.01) and TLL on MTI (p=0.03) scans. No significant relationships between the extent of T1-weighted lesion loads and the presence of any neuropsychological impairment. Mean MTR of both MS lesions and whole brain tissue was lower in patients with frontal lobe impairment (p=0.04). MRI lesion loads correlated significantly with some neuropsychological test scores. CONCLUSIONS: Lesion loads on PD-weighted MRI and MTI-derived measures are associated with cognitive decline in MS patients. Overall macroscopic and microscopic brain damage is more important than the corresponding regional brain disease in determining deficits of selective cognitive domains.  相似文献   

20.
Higher education is associated with less age-related decline in cognitive function, but the mechanism of this protective effect is unknown. The authors examined the effect of age on the relation between education and brain activity by correlating years of education with activity measured using functional MRI during memory tasks in young and older adults. In young adults, education was negatively correlated with frontal activity, whereas in older adults, education was positively correlated with frontal activity. Medial temporal activity was associated with more education in young adults but less education in older adults. This suggests that the frontal cortex is engaged by older adults, particularly by the highly educated, as an alternative network that may be engaged to aid cognitive function. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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