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61.
The psychological well-being of mothers raising a child with a developmental disability varies with the nature of the disability. Most research, however, has been focused on Down syndrome and autism. We added mothers whose adolescent or young adult son or daughter has fragile X syndrome. The sample was comprised of mothers of a child with fragile X syndrome (n = 22), Down syndrome (n = 39), or autism (n = 174). Mothers of individuals with fragile X syndrome displayed lower levels of well-being than those of individuals with Down syndrome, but higher levels than mothers of individuals with autism, although group differences varied somewhat across different dimensions of well-being. The most consistent predictor of maternal outcomes was the adolescent or young adult's behavioral symptoms.  相似文献   
62.
A four-generation pedigree exhibiting early-onset autosomal dominant Alzheimer disease (AD) with spastic paraplegia, dystonia, and dysarthria due to a novel 6-nucleotide insertional mutation in exon 3 of the presenilin 1 gene (PS1) is described. Serial examinations, PET scans, and autopsy revealed that the mutation in this highly conserved portion of PS1 causes an aggressive dementia that maintains the usual regional hierarchy of disease pathology while extending abnormalities into more widespread brain areas than typically seen in AD.  相似文献   
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Awareness of deficit was examined in 24 patients with Alzheimer's disease (AD) and their spouses (for a total of 48 participants) using performance prediction-postdiction and questionnaire discrepancy (QD) paradigms. Participants estimated their own memory performances as well the performances of spouses and of a fictional, memory-disordered patient observed on videotape. Patients overpredicted self-performances, but the extent of overestimation decreased for postdictions. Patients and caregivers accurately estimated caregiver performances but overestimated performances of the fictional patient. QD data revealed that patients underestimated their difficulties performing daily functioning tasks as compared with caregiver reports. Awareness of deficit is a complex ability, involving dissociable cognitive processes. AD patients may display intact immediate awareness of memory dysfunction but fail to incorporate incidents of memory failure into generalized self-belief systems.  相似文献   
65.
Assessment and validation of imaging methods and technologies   总被引:1,自引:0,他引:1  
In summary, the group identified many challenges and opportunities facing those wishing to conduct rigorous assessment and validation of imaging technologies. Specific needs and recommendations were outlined by the group. Overall, it was felt that the field has made great progress in the past several years, and that the future is promising.  相似文献   
66.
RATIONALE AND OBJECTIVES: This study was performed to assess the extent of agreement among radiologists and nonradiologists in perception of diagnostic certainty conveyed by words and phrases commonly used in radiology reports. MATERIALS AND METHODS: The study was performed in a large academic radiology department. To determine the commonly used terminology for conveying diagnostic certainty in radiology reports, 12 randomly selected radiologists from six different subspecialties were interviewed. The authors identified the 15 most commonly used words and phrases and included these in random order in a questionnaire sent to all staff radiologists (n = 45) and to 158 referring physicians. Physicians were asked to rank the 15 phrases in order of the diagnostic certainty conveyed by each, from 1 (most certain) to 15 (least certain), using each number only once. The kappa statistic was used to assess agreement in rank order among physicians. RESULTS: The questionnaire response rate was 76% (n = 34) for radiologists and 49% (n = 78) for nonradiologists. There was excellent agreement among radiologists (kappa = 0.95) and nonradiologists (kappa = 0.93) in the rank order for the phrase diagnostic of. Although there was good agreement (kappa = 0.45) among radiologists for the word unlikely, agreement among nonradiologists was poor (kappa = 0.27). There was very poor agreement among all physicians for the rank order of the other 13 phrases. CONCLUSION: Among radiologists and nonradiologists, concordance was poor regarding the diagnostic certainty associated with phrases commonly used in radiology reports. Because poor agreement could lead to suboptimal quality of care, the standardization of terminology would benefit all parties.  相似文献   
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68.
Endodontic therapy was performed on 14 teeth in juveniles with inflamed or necrotic pulps. The patients were recalled at 6-month intervals for radiological and clinical examinations. After 1 yr, periapical surgery was performed on six teeth. After 18 months, 5 more patients were subjected to periapical surgery and, after 2 1/2 years, 3 more patients had periapical surgery. A small block section containing the root tip and surrounding tissues was removed from all of the patients. Radiographs showed reductions in size, but not elimination, of periapical lesions. Histological examinations revealed that most root canals were overfilled. Inflammation persisted around zinc oxide-eugenol particles beyond the tooth apexes. In addition, gutta-percha overfilling enhanced the proliferation of cell rests of Malassez. In some cases, dentin filings were found at and beyond the tooth apexes. The formation of new hard tissue was stimulated by the presence of dentin chips.  相似文献   
69.
Current synthetic vascular prostheses do not acquire lining of vascular endothelium in humans or dogs. Endothelial seeding of vascular grafts has been proposed as a means of reducing the thrombogenicity of these grafts. We examined feasibility of cultivating endothelial cells (EC) by tissue culture technique and their subsequent seeding onto small diameter polytetra fluoroethylene (PTFE) grafts. Twenty adult dogs underwent common carotid artery interposition with 4 mm PTFE grafts. Ten dogs received seeded and the remaining ten received unseeded grafts. Grafts were removed at 4 and 12 weeks and their gross/morphological features compared. Cumulative patency rates for seeded grafts were 70% as compared to unseeded ones 30%. Seeded grafts were completely surfaced with a mono-layer of endothelium by 4 weeks. Small graft patency appears to be related to the establishment of an endothelial surface, the development of which is clearly facilitated by seeding with autogenous endothelium.KEY WORDS: Endothelial cell seeding, Vascular grafts  相似文献   
70.
Of patients who completed the same medical history questionnaire twice within a certain time period, 66% had at least 1 significant omission in their history. Consideration is given to the merits of a national medical history computerized database.  相似文献   
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