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131.
M Komeda A DeAnda JR Glasson AF Bolger GT Daughters NB Ingels DC Miller 《Canadian Metallurgical Quarterly》1997,64(5):1250-1255
BACKGROUND: The benefit of left ventricular (LV) unloading for preserving LV function is commonly accepted, but its efficacy remains incompletely defined. METHODS: We studied the influence of complete LV unloading on LV systolic and diastolic mechanics using an in situ isovolumic preparation with two different coronary perfusion pressures (CPPs) in 12 dogs during prolonged normothermic cardiopulmonary bypass. RESULTS: Multivariate analysis of covariance with time as a covariate revealed that a high CPP (143 +/- 36 mm Hg; n = 6) was associated with better preservation of systolic LV function over time as assessed by LV end-systolic elastance (p < 0.001) and the end-systolic pressure-volume relation physiologic intercept (p < 0.001) compared with a moderate CPP (107 +/- 18 mm Hg; p < 0.005 versus a high CPP by t-test; n = 6). Dobutamine (2 micrograms.kg-1.min-1) improved LV end-systolic elastance (p < 0.005) and LV physiologic intercept (p < 0.01) only in the high-CPP group. Conversely, impaired LV diastolic function (as measured by LV stiffness) was observed (p < 0.001) with a high CPP, but did not change with a moderate CPP. CONCLUSIONS: These observations in canine hearts suggest that complete LV unloading may not preserve LV systolic function adequately over time when CPP is maintained in the accepted clinical range. A higher CPP is required to prevent deterioration over prolonged cardiopulmonary bypass times, but diastolic dysfunction still occurs. 相似文献
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AF Wechsler 《Canadian Metallurgical Quarterly》1977,40(3):303-305
A focal aphasic syndrome was the first and outstanding manifestation of a degenerative, presenile dementia in a 67 year old man. Computerised axial tomography showed a strikingly dilated left Sylvian fissure--particularly in its posterior aspect--in the presence of moderate diffuse cortical atrophy. The radiographic findings correlated well with the clinical data. This is the first report of an aphasic disturbance of language as the initial symptom is presenile dementia. 相似文献
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G Ursin RG Ziegler AF Subar BI Graubard RW Haile R Hoover 《Canadian Metallurgical Quarterly》1993,137(8):916-927
To identify systematically the nutrient and food group intakes associated with a low-fat diet, the authors used the detailed dietary information collected from 10,306 individuals aged 32-86 years in the 1982-1984 National Health Epidemiologic Follow-up Study. Intakes of vitamin C and percentages of calories from carbohydrates, dietary fiber, poultry, low-fat dairy products, fruits, vegetables, cereals, and whole grains were markedly higher, while intakes of protein, total fat, saturated fat, oleic and linoleic acids, cholesterol, sodium, all red meats, high-fat dairy products, eggs, nuts, white bread, fried potatoes, desserts, fats, and oils were much lower in the quartile with the lowest percentage of calories from fat. These dietary patterns associated with a low-fat diet were essentially constant across strata of age, sex, race, and socioeconomic status. This study suggests that individuals on a low-fat diet substitute certain carbohydrate-rich foods such as fruits and vegetables for fat. Given these associations between low-fat diets and other dietary factors independently associated with certain cancers, these dietary factors should be considered potential confounders in studies of dietary fat and these cancers. 相似文献
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Otitis media with effusion (OME) is a disease most commonly affecting the paediatric population. However, it is a condition that is also seen in adults and does lead to significant morbidity. We studied the effect of surgical treatment of OME in an adult population and found that the subjective relief of symptoms exceeded the objective audiometric gain. In children where subjective symptoms are perhaps more difficult to assess the clinician needs to beware of underestimating the effect of a hearing loss. 相似文献
139.
PA Groenen M Makhdoum JL van den Brink MH Stollman AF Snik P van den Broek 《Canadian Metallurgical Quarterly》1996,116(6):785-790
Electrically evoked brainstem responses (EABR) and event-related cortical potentials were recorded in seven postlingually deaf adults who were experienced users of a Nucleus multichannel cochlear implant. The patients were divided into two subgroups: good performers and moderate performers. Poor EABR were found in two of the moderate performers. The latencies and amplitudes of the cortical N1 P2 complex in the good performers were within the same range as those of subjects with normal hearing, but were deviant in the group of moderate performers. This may indicate disturbed cochleotopical organization of the auditory cortex in the latter group. P300 measurements in the good performers showed normal latencies, whereas in the moderate performers they were prolonged. The results suggest that the outcomes of electrophysiological measurements to assess the integrity of a patient's auditory neural system on a brainstem and a cortical level, are related to the patient's performance with the cochlear implant. 相似文献
140.