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Health care services for the chronically ill are provided through a fragmented patchwork of activities by health care professionals. This article traces some of the origins of attitudes toward the chronically ill and identifies the problems created by disjointed patterns of care. A route for change that is humanistically based and uses a matrix model for care and management is suggested.  相似文献   
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BACKGROUND: Prognostic models need to be tested in external validation studies to assess generalizability. Recursive partitioning analysis (RPA), a prognostic system based on the creation of a classification tree, has been proposed as a classification method in patients with head and neck carcinoma. The aim of this study was to compare the RPA and Union Internationale Contre le Cancer (UICC) TNM classification systems in patients with head and neck carcinoma treated consecutively in a single center. METHODS: A total of 2166 patients with carcinomas of the oral cavity, oropharynx, hypopharynx, and larynx was classified according to both the RPA and the TNM classification systems, and the results were compared. The endpoints considered were observed survival and survival free of locoregional tumor. The two methods of classification were evaluated objectively by use of measures of intrastage homogeneity (hazard consistency), interstage heterogeneity (hazard discrimination), predictive power (outcome prediction), and patient distribution between stages (balance). RESULTS: When the endpoint considered was observed survival, there were no clinically relevant differences between the two classifications. However, when the endpoint was locoregional control, the RPA system was sensitive to the type of treatment used, and it was not generalizable. CONCLUSIONS: To evaluate generalizability, new classification proposals need external validation studies that objectively measure the quality of the model. The performance of the RPA system was not reproducible in our cohort of patients when the endpoint evaluated was locoregional control.  相似文献   
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We investigated the expression of choline acetyltransferase, a specific marker for cholinergic neurons, in control and spinal muscular atrophy fetuses and newborns. By immunoblot we observed at 12 and 15 weeks a similar pattern of choline acetyltransferase expression in spinal muscular atrophy with respect to controls, although at 22 weeks this expression was reduced, probably due to a smaller number of motor neurons in the spinal muscular atrophy spinal cord. By immunohistochemistry, the counting of positive and negative motor neurons for choline acetyltransferase immunostaining in control and spinal muscular atrophy fetuses showed a similar proportion at all stages analyzed. The choline acetyltransferase-negative motor neurons were of similar appearance in both groups. After birth, chromatolytic motor neurons were detected in spinal muscular atrophy, all of which were choline acetyltransferase-negative. Our results in spinal muscular atrophy fetuses indicate that choline acetyltransferase immunostaining does not identify early events in neuronal pathogenesis and suggest that the spinal muscular atrophy surviving motor neurons may not be dysfunctional during this period. Furthermore, spinal muscular atrophy choline acetyltransferase-negative motor neurons showed detectable pathological changes only after birth, indicating that choline acetyltransferase is a late marker for motor neuron degeneration and not a primary contributing factor in this process.  相似文献   
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A superficial spreading melanoma (Breslow thickness 0.4 mm) was diagnosed in a 65-year-old candidate for heart transplantation due to refractory end stage heart failure. After extensive review of the literature (USA and Europe), no clear guidelines about the management of candidates for transplantation with a previous diagnosis of melanoma were found. As this patient had a 5-year probability of survival higher than 95% and heart transplantation was necessary for saving his life, the final decision was to perform the transplantation. Unfortunately, the patient died of heart failure before a suitable heart became available. This case stresses the need for early and continuous dermatological evaluation of all candidates for solid organ transplantation. Clear guidelines for screening of skin cancer before transplantation are needed.  相似文献   
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Purpose Imaging with metaiodobenzylguanidine (MIBG) is used for the assessment of neuronal dysfunction in various cardiovascular disorders. Although valuable information is obtained by resting MIBG imaging, it is conceivable that competitive interference with the re-uptake mechanism would exaggerate MIBG defects and might unmask subclinical neuronal dysfunction. Tricyclic antidepressants, such as amitriptyline, have been reported to significantly increase cardiac MIBG washout and inhibit uptake into presynaptic neurons. This study was undertaken to assess whether a single oral dose of amitriptyline could influence cardiac MIBG distribution.Methods Six patients (aged 62–81 years; four males, two females) who had demonstrated a normal cardiac MIBG scan during work-up for movement disorders were studied. The patients underwent a second 123I-MIBG study after oral administration of 25 mg amitriptyline within 1 week. Single-photon emission computed tomography images were acquired at 4 h to assess the regional distribution of MIBG, after generation of polar maps and employing a 20-segment model. Mean percentage of peak activity was calculated for each segment at rest and after amitriptyline administration.Results After amitriptyline administration, there was a decrease in regional MIBG uptake in 10±4 segments per patient [62/120 segments (52%): 37 segments with a 5–10% decrease, 25 segments with a >10% decrease]. This change was statistically significant in lateral (P=0.003), apical (P<0.0001) and inferior (P=0.03) regions.Conclusion A single oral dose of amitriptyline can induce changes in the uptake and retention of cardiac MIBG, indicating the feasibility of use of pharmacological intervention in cardiac neurotransmission imaging.  相似文献   
79.
OBJECT: Continuous intracranial pressure (ICP) monitoring is performed in selected patients with hydrocephalus to determine whether shunt placement is required. The mean ICP is usually calculated from end-hour readings manually recorded by nurses. The aim of this study was to evaluate the accuracy of manual recordings by comparing nurses' end-hour ICP readings with those of an online computerized ICP monitoring system that records one ICP value per second. METHODS: Continuous ICP monitoring was performed using a fiberoptic extradural sensor in 115 patients with hydrocephalus of different origins. A notebook computer was connected to an ICP monitor and was programmed to register one ICP value per second. In all patients, mean ICP values were calculated from data recorded manually by nurses at the end of every hour and from data recorded by the computer within the preselected time period. The two methods were compared using correlation analysis and the Bland and Altman method. The median number of ICP values noted manually by the nurses in each patient was 17 (interquartile range 15-18 readings), and that recorded by the software was 61,200 (interquartile range 54,000-64,800 readings). The correlation coefficient of the mean ICP values recorded by both methods was r = 0.99 (p < 0.001). The Bland and Altman analysis revealed a mean difference of 0.3 +/- 1.26 mm Hg between the two methods and that they were equally valid with all mean ICP values. CONCLUSIONS: The recording of end-hour ICP values by nurses is an accurate method of calculating the mean ICP after prolonged ICP monitoring in patients with hydrocephalus.  相似文献   
80.
Several studies have evaluated executive function in depressed patients, and the results vary from significant impairment relative to controls to virtually intact performances. To better comprehend executive impairment in elderly patients with major unipolar depression, the performance of 21 elderly depressed patients was compared with that of 19 elderly normal controls on executive tasks. The relationships between memory deficits and depression severity and between memory deficits and executive dysfunction were also examined. Depressed patients' performance was significantly worse than that of controls on almost all executive tasks. Their score for logical memory was significantly correlated with that for several executive tasks. Executive performance was also correlated with depression severity. Unipolar depressed patients present executive deficits. Memory failure in these patients may reflect impairment in retrieval processes, which in turn depends on executive function. Executive deficits are associated with depression severity. These results may be useful in the differential diagnosis between depression and early Alzheimer's disease.  相似文献   
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