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71.
BACKGROUND: The population aged 65 and older is often analyzed in three categories: young-old (65-74), middle-old (75-84), and oldest-old (> or = 85). This may blind heterogeneity within the oldest category. New, large data sets allow examination of the very oldest-old (e.g., aged > or = 95) and contrasts with those who are younger. METHODS: We determined the annual change of prevalence of physical and cognitive function, and of disease problems in the old to very oldest-old, using data from existing Resident Assessment Instrument records from nursing homes in seven states during 1992-1994. We used data from 193,467 unique residents aged 80 or older, including 6,556 residents aged 100 or older. We computed the prevalence, by age, of selected conditions: physical and cognitive function, diseases, problem behavior, mood disturbance, restraint use, falls, weight loss, eating less, body mass index, chewing and swallowing problems, incontinence (bowel and bladder), catheter use, and selected diagnoses. RESULTS: Prevalence of all measures of physical and cognitive dysfunction increased most rapidly with each year of age among the very oldest-old. Most of the slope changes occurred from 95 to 100 years of age. Such changes are less pronounced or not seen in measures of disease prevalence. CONCLUSIONS: Accelerated change in prevalence of dysfunction seen in the nursing home population may suggest a change in the mechanisms of aging that occur after the mid-nineties. Examination of the very oldest-old may provide new insight into the nature of the aging process.  相似文献   
72.
Some theories of brain function emphasize the interactions between brain areas as the major determinant of cognitive and behavioral operations. We explored such interactions in a PET study of episodic memory retrieval having three retrieval conditions, with differing levels of retrieval success. Functional connectivity of voxels located within Brodmann areas 10 and 45/47 in the right prefrontal cortex (RPFC) and the left hippocampus (LGH) with the rest of the brain was estimated using partial least squares. Area 10 and LGH showed an opposite pattern of functional connectivity, with a large expanse of bilateral limbic cortices that was equivalent in all tasks. However, during high retrieval, area 45/47 was included in this pattern. The results suggest that activity in portions of the RPFC reflects either memory retrieval mode or retrieval success, depending on other brain regions to which it is functionally linked. Hum. Brain Mapping 5:323–327, 1997. © 1997 Wiley-Liss, Inc.  相似文献   
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Patients with Fetal Alcohol Syndrome (FAS) and Fetal Alcohol Effects (FAE) often have difficulty functioning appropriately in everyday life and seem to employ poor problem-solving strategies. Tests of executive function are relevant for quantifying the functional deficits and underlying real-life problems associated with prenatal alcohol exposure. This study considers two pathways for the effects of prenatal alcohol on executive function: a direct effect and an indirect effect through prenatal alcohol's effect on IQ. We compared 30 men who had been diagnosed with FAS or FAE with young adults participating in a longitudinal prospective study (n = 419) and 15 control participants that comprised a comparison group. This study is unique in its analysis of the same battery of assessments of executive function in both a large low dose longitudinal study sample and a clinically diagnosed group. Participants were evaluated on 9 tests (including 58 scores) of executive function. For some but not all of the tests in this executive function battery, the decrement in the alcohol exposure group is greater than would be predicted from their IQ scores. We found that 3 of 6 Stroop scores, 2 of 4 Trails scores, 9 of 16 Wisconsin Card Sorting scores, 1 of 2 Ruff's Figural Fluency scores, and 2 of 4 Consonant Trigrams scores appear to be particularly sensitive to the direct effects of prenatal alcohol damage for patients with FAS and FAE. The findings suggest that these executive function tests would be particularly useful in clinical evaluations of persons suspected of fetal alcohol damage because they would not simply reflect deficits in IQ or facial stigmata.  相似文献   
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An experiment was designed to determine whether or not acute pneumococcal pneumonia in dogs is associated with intravascular thrombosis, or with angiographic features distinguishable from pulmonary embolism. In dogs with normal baseline chest radiographs and perfusion scans, pneumonia was produced by transbronchial instillation of type III pneumococcus. After 2 days, perfusion scans demonstrated discrete appropriate defects. In vivo magnification pulmonary arteriography, postmortem pulmonary arteriography, and histologic examination disclosed no evidence of thrombi.  相似文献   
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Transluminal angioplasty of the abdominal aorta   总被引:3,自引:0,他引:3  
Transluminal angioplasty of the abdominal aorta was performed in 6 women between 49 and 69 years of age with histories of cigarette smoking. Five had a relatively small aorta. This procedure is effective in treating focal aortic stenoses.  相似文献   
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K W Seo  J J Bookstein  H S Brown 《Radiology》1979,132(3):603-604
Angiography demonstrated intussusception in a patient with recurrent unexplained gastrointestinal hemorrhage after outside barium studies had been interpreted as normal. Magnification arteriography provided an unusually clear depiction of the anatomic derangement of intussusception.  相似文献   
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