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771.
Early alexia and higher visual impairments characterize Posterior cortical atrophy (PCA), a progressive dementing syndrome most often caused by Alzheimer disease. Posterior cortical atrophy is rare, and the nature of the visual impairments in PCA are unclear. The authors observed two patients who had an insidiously progressive reading difficulty characterized by letter-by-letter reading and otherwise intact cognitive functions. Over time, these patients developed "ventral simultanagnosia" with preserved detection of multiple stimuli but inability to interpret whole scenes. Subsequently, they progressed to Balint syndrome with "dorsal simultanagnosia," optic ataxia, and oculomotor apraxia. Structural imaging was normal, but functional imaging revealed posterior cortical dysfunction. On a letter reading task, both patients had a word superiority effect, and on a whole word reading task, they could not read most words with missing or crosshatched letters. An inability to assess whole scenes progressed to an inability to detect more than one stimulus in an array. These findings suggest an evolution of PCA with progressive difficulty in visual integration beginning with letters, progressing to whole scenes, and culminating in Balint syndrome. These changes may reflect an extension of the pathophysiology of PCA from the extrastriate visual cortex to its occipitotemporal and occipitoparietal connections. 相似文献
772.
BK Eriksson EG Larsson BM Skogseid AM L?fberg LE L?relius KE Oberg 《Canadian Metallurgical Quarterly》1998,83(11):2293-2301
BACKGROUND: Patients with neuroendocrine gastrointestinal tumors usually present with inoperable metastatic disease and severe hormonal symptoms. Specific chemotherapy, interferon-alpha (IFN), and somatostatin analogs are established therapies for these patients, but all of them eventually fail. Hepatic arterial embolization can provide reduction of both hormonal symptoms and tumor burden in these patients. METHODS: Between 1981 and 1995, a total of 55 liver embolizations with gel foam powder were performed on 41 patients with histopathologically verified neuroendocrine tumors; 29 had carcinoid tumors and 12 had endocrine pancreatic tumors (EPTs). All patients had received medical treatment, including chemotherapy (n = 18), IFN (n = 31), and octreotide (n = 19), and were experiencing treatment failure when liver embolization was performed at a median of 37 months after diagnosis of liver metastases. Medical treatment was continued after embolization. RESULTS: An overall objective response was noted in 15 of 29 patients with carcinoid tumors (52%). The median duration of effect was 12 months in patients with midgut carcinoid tumors. An overall objective response was observed in 6 of 12 patients with EPTs (50%), with a median duration of effect of 10 months. Adverse events were observed, and, in agreement with earlier reports, the rate of serious complications was 10%. Survival analyses showed a median survival of 80 months and a 5-year survival rate of 60% from the performance of embolization on patients with midgut carcinoid tumors, whereas for patients with EPTs the median survival from embolization was only 20 months. CONCLUSIONS: Liver embolizations performed relatively late in the clinical course in our series appeared to be as effective as "early" embolizations in other series of patients with carcinoid tumors. The results for those with EPTs were poorer, and earlier embolizations may result in better outcomes for these patients. Considering the morbidity associated with the procedure, it is imperative to select patients according to extent of liver involvement, severity of carcinoid heart disease, and somatostatin receptor status. 相似文献
773.
SY Ryu KS Jeong SJ Park BG Mheen HY Son WK Yoon SW Cho BK Park SH Kim 《Canadian Metallurgical Quarterly》1998,12(2):187-194
OBJECTIVE: Restorative proctocolectomy for mucosal ulcerative colitis is well established. However, the effect of age on physiologic sphincter parameters is poorly understood. Our objective was to determine whether age at the time of restorative proctocolectomy correlates with physiologic changes. SUMMARY BACKGROUND DATA: In the approximately 20 years during which restorative proctocolectomy has been performed for ulcerative colitis, the indications have changed. Initially, the procedure was recommended only in patients under approximately 50 years. However, the procedure has been considered in older patients because of the increasing age of our population, the increasing frequency of recognition of patients during the "second peak" of mucosal ulcerative colitis, and the decreasing morbidity rates, due to the learning curve and to newer techniques, such as double-stapling. Few authors have presented data analyzing the effects of this operation in older patients. METHODS: One hundred twenty-two patients who had undergone a two-stage restorative proctocolectomy for mucosal ulcerative colitis were divided into three groups according to age: group I (>60 years), 11 men, 6 women; group II (40-60 years), 29 men, 18 women; and group III (<40 years) 29 men, 29 women. The patients were prospectively evaluated using anal manometry and subjective functional results. Comparisons were made before surgery, after colectomy and before closure of ileostomy, and at 1 or more years after surgery. RESULTS: There were no significant differences among the groups relative to manometric results, frequency of bowel movements, incontinence scores, or overall patient satisfaction. The postoperative mean and maximum resting pressures were significantly reduced (p < 0.001), and conversely the sensory threshold (p < 0.005) and capacity (p < 0.001) were increased in all groups up to 1 year after surgery. There were no statistically significant changes in the squeeze pressure or length of the high-pressure zone in any group at any point in time. After surgery, the mean and maximum resting pressures had returned to 80% of their original values. CONCLUSION: Although anorectal function is transiently somewhat impaired after restorative proctocolectomy, the impairment is not an age-related phenomenon. 相似文献
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BK Bailes 《Canadian Metallurgical Quarterly》1999,69(1):254-258
Hyperthyroid disorders occur in older people and often are present with atypical findings or as apathetic hyperthyroidism. Hyperthyroidism exacerbates underlying chronic disease, especially cardiovascular conditions. Elderly people can be treated successfully and stabilized with careful screening, astute diagnostics, and appropriate therapy. 相似文献
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Fifty aborted foetus samples were diagnosed for the presence of equine herpes virus-1 (EHV-1) by polymerase chain reaction (PCR) technique. Specific primer pair for amplification of a particular segment of EHV-1 DNA in gc region having 3 Hae III restriction endonuclease sites was used. A 409 base pair segment obtained as PCR amplification product in 9 samples was digested with Hae III to confirm the presence of EHV-1 as the infectious agent in aborted tissues. It was observed that PCR technique was more sensitive, specific and rapid than the conventional virological diagnostic methods. 相似文献
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