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Conventional risk factors have very low predictive power in identifying haemodialysis patients at high risk of vascular accidents. A role for apolipoprotein E isotypes was looked for in a small, but rigorously defined, cohort of longterm haemodialysis patients. In individuals with high vascular risk, as identified by higher common carotid intima/media thickness, we found an excess of apolipoprotein E4 alleles. This preliminary result requires confirmation in large patient cohorts.   相似文献   
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The present study reports the results of a prospective, 8-year follow-up study of 100 hyperactive and 60 normal children followed from childhood into adolescence. Ratings of child behavior problems and family conflicts as well as direct observations of mother-child interactions were taken in childhood and again at adolescent follow-up. At outcome, hyperactives continued to have more conduct and learning problems and to be more hyperactive, inattentive, and impulsive than controls. Hyperactives were also rated by their mothers as having more numerous and intense family conflicts than the normal controls, although the adolescents in both groups did not differ in their own ratings of these conflicts. Observations of mother-adolescent interactions at outcome found the hyperactive dyads displaying more negative and controlling behaviors and less positive and facilitating behaviors towards each other than in the normal dyads. These interaction patterns were significantly related to similar patterns in mother-child interactions observed 8 years earlier. Mothers of hyperactives also reported more personal psychological distress than normal mothers at outcome. Further analyses of subgroups of hyperactives at outcome, formed on the presence or absence of ADHD and oppositional defiant disorder (ODD), indicated that the presence of ODD accounted for most of the differences between hyperactives and normals on the interaction measures, ratings of home conflicts, and ratings of maternal psychological distress. Results suggest that the development and maintenance of ODD into adolescence in hyperactive children is strongly associated with aggression and negative parent-child interactions in childhood.  相似文献   
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Available research provides compelling evidence that ADHD is associated with significantly increased risks for various adverse outcomes while driving, including increased traffic citations (particularly speeding), motor vehicle crashes for which the driver is at fault, repeated crash occurrences,and more severe crashes as determined from dollar damage and likelihood of bodily injuries from the crash. Not surprisingly, teens and adults with ADHD are more likely to have their licenses suspended and even fully revoked. Research further suggests that these driving risks cannot be accounted for by the comorbid disorders likely to be associated with ADHD, such as ODD, conduct disorder (CD), depression, or anxiety, or by lower than normal levels of intelligence.Recent attempts to study the processes or mechanisms involved in driving in adults with ADHD offer some explanation of how the disorder conveys such increased risks. Driving can be conceptualized usefully as involving at least three or more dimensions or levels, including basic cognitive abilities necessary for driving (operational), actual skills for maneuvering the vehicle in traffic (tactical), and the more executive, goal-directed aspects of driving(strategic). The findings of studies indicate that ADHD interferes with the basic operational components of driving by means of the impairments it produces in attention, resistance to distraction, response inhibition, slower and more variable reaction time, and the capacity to follow rules that may compete with ongoing sensory information. Accumulating evidence also points to a problem in the tactical level of driving, such that those with ADHDrate themselves and are rated by others as employing less safe driving habits during their normal operation of a vehicle than are adults in community control groups. Although this has been more elusive to demonstrate through the use of simple laboratory-based driving simulators. more modern virtual reality driving platforms offer greater promise in providing more realistic appraisals of driving performance and thus more direct evidence of the problems that occur at the tactical level from the disorder. Research has not examined the impact of ADHD at the higher strategic level or goal-directed aspects of driving. But given the mounting evidence that ADHD adversely affects executive functioning in adults, the author and colleagues anticipate that this level also will be found to be impaired in adults with ADHD. Indeed,it recently has been shown that adults with ADHD overestimate their driving abilities relative to normal adults, a problem that likely can be ascribed to more limited self-awareness and related meta-cognitive abilities for self-evaluation arising from the disorder.Although further research on the driving problems posed by ADHD is in order, sufficient evidence exists to warrant focus on possible treatments that may serve to improve these driving problems and reduce the risk for these adverse outcomes. High on the list of such treatments deserving further research and clinical attention is the use of stimulant medication. The more recent noradrenergic reuptake inhibitor. atomoxetine, also may have some promise in this regard. Studies are underway in the author's driving laboratory to see if this is the case. Meanwhile, adults with ADHD and parents of teens with ADHD should be advised about these heightened risks and encouraged to take steps that may reduce them, including the consideration of more graduated licensing for adolescents with ADHD and the possible use of stimulant medication in teens and adults with ADHD while they are operating a motor vehicle.  相似文献   
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Hodgkin disease: CT of the thymus   总被引:2,自引:0,他引:2  
Heron  CW; Husband  JE; Williams  MP 《Radiology》1988,167(3):647-651
The computed tomography (CT) scans in two groups of patients with Hodgkin disease were reviewed to determine the frequency of thymic enlargement. In 50 CT scans from 50 patients with evidence of thoracic disease on CT scans who were examined for primary staging, the thymus was enlarged in 15 of 50 (30%). Fifty CT scans were obtained from 44 patients at the time of 50 separate episodes of known or suspected relapse. Relapse occurred in the mediastinum in 12 episodes, lung parenchyma in five, and both sites in one. Thymic enlargement thought to be due to involvement by disease was present in seven of 18 (38%). Mediastinal disease was associated with thymic enlargement in all but one patient in whom a thymic cyst developed after radiation therapy. Differentiation of thymic enlargement from enlarged superior mediastinal lymph nodes was easily made in all but two patients. Thymic enlargement in the absence of lymph node enlargement may indicate a different disease, since isolated Hodgkin disease of the thymus is uncommon. Primary thymic tumor should be considered initially, whereas after treatment, rebound hyperplasia of the thymus may be the cause of enlargement.  相似文献   
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Solitary bronchioloalveolar carcinoma: CT criteria   总被引:14,自引:0,他引:14  
The computed tomographic (CT) scans of 30 patients with solitary bronchioloalveolar carcinoma were reviewed. Common features at CT included the peripheral or subpleural location of a pulmonary mass (25 cases), pseudocavitation (18 cases), heterogeneous attenuation (17 cases), irregular margins forming a star pattern (22 cases), and pleural tags (21 cases). Using these CT criteria, four independent observers attempted to identify cases of bronchioloalveolar carcinoma from a larger sample of lung cancers and benign lesions by categorizing a series of test cases into four probability categories. Although the bronchioloalveolar carcinomas were correctly ranked in the two highest probability categories 75% of the time (in 45 of 60 cases), there was considerable overlap with other lung lesions, particularly with adenocarcinoma and large cell undifferentiated carcinoma. However, even though the typical features of bronchioloalveolar carcinoma are not invariable or highly specific, they are characteristic enough to suggest the diagnosis.  相似文献   
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OBJECTIVE: The aim was to establish the potential efficacy, tolerabilityand side-effect profile of electromagnetic therapy as an adjunctto conventional dressings in the treatment of venous leg ulcers. METHOD: A prospective, randomized, double blind controlled clinicaltrial was carried out in a dedicated leg ulcer clinic basedin one urban general practice. Nineteen patients with leg ulcersof confirmed venous aetiology were assessed. The main outcomemeasures were rate and scale of venous leg ulcer healing, changesin patient-reported pain levels, quality of life, degree ofmobility, side effect profile and acceptability to patientsand staff. RESULTS: Sixty-eight per cent of patients attending this dedicated clinicachieved improvements in the size of their ulcer (4, 21%, healedfully) and in reduced pain levels (P < 0.05) during the trial,despite the chronicity of ulcer histories. Patients treatedwith electromagnetic therapy at 800 Hz were found at day 50to have significantly greater healing (P < 0.05) and paincontrol (P < 0.05) than placebo therapy or treatment with600 Hz. All patients reported improved mobility at the end ofthe study. The electromagnetic therapy was well tolerated bypatients, with no differences between groups in reporting adverseevents, and proved acceptable to staff. CONCLUSION: Despite the small numbers in this pilot study, electromagnetictherapy provided significant gains in the healing of venousleg ulcers and reduction in pain. Keywords. Electromagnetic therapy, RCT, leg ulcers, primary care.  相似文献   
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