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61.
62.
Compensation filters allow increased visibility of detail in chest, shoulder, spine, hip, knee, and foot radiographs. This study examines use of an anatomic compensation filter to improve imaging in pedal radiographs. Anteroposterior radiographs were obtained of 25 cadaveric feet at two settings with and without the compensation filter. Densitometer readings were taken at ten forefoot anatomic sites. The compensation filter produced statistically significant reductions in densitometer readings at all anatomic sites and at both radiographic settings. Filtration improved imagery of bony structures, provided excellent soft-tissue visualization, and lowered patient exposure.  相似文献   
63.
Six healthy lean male adults, given a mixed meal containing 3190 kJ (16% from protein, 44% from carbohydrate and 40% from fat) were studied for the next 370 min using arteriovenous cannulation techniques across superficial and deep forearm tissues. The meal produced no significant change in forearm blood flow or skin temperature. The major differences between superficial and deep forearm tissues were (a) creatinine release by deep tissues but not superficial tissues; (b) the release of non-esterified fatty acids (NEFA) by superficial tissues and uptake by deep tissues; and (c) the more prolonged large positive arteriovenous concentration difference for glucose across deep than superficial tissues. The similarities were (a) general pattern of individual amino acid exchanges and transient positive amino acid N balance after meal ingestion; (b) consistent uptake of glutamate and release of glutamine (the main carrier of N out of superficial and deep forearm tissues); (c) the magnitude of the arteriovenous concentration differences for glucose, NEFA and total amino acids were related to the changes in their circulating concentrations and to the oxidation of carbohydrate, fat, and protein in the whole body; and (d) increases in the arterio-deep venous and arterio-superficial venous differences for glucose did not result in increased release of lactate, alanine or pyruvate, implying no increase in the activity of glucose-lactate and glucose-alanine cycles between forearm tissues and the liver. This study suggests that in a number of ways superficial and deep tissues can be regarded, at least qualitatively, as behaving as a 'single metabolic unit'.  相似文献   
64.
Perineal one-stage pull-through for Hirschsprung's disease   总被引:20,自引:0,他引:20  
PURPOSE: The aim of this study was to present the strategy of a one-stage repair of Hirschsprung's Disease (HD) performed via a transanal approach. METHODS: Ten consecutive neonates and one toddler underwent transanal repair for biopsy-proven HD. A rectosigmoid transition zone was suggested by contrast enema in all patients. The mean age at operation for the neonates was 4 days. A mucosal dissection was begun 0.5 cm proximal to the dentate line. Once the correct plane was established, up to 15 cm of bowel can be resected without ligating vessels or performing a transabdominal dissection. The proximal extent of dissection was delineated by the presence of ganglion cells seen on frozen section analysis. RESULTS: The mean operating time was 105 minutes. There were no intraoperative or postoperative complications. All children had the presence of ganglion cells confirmed postoperatively on permanent sections. The mean hospital stay was 2 days. All children averaged three to six bowel movements per day without oral or enema therapy. CONCLUSIONS: The perineal one-stage operative pull-through (POOP) procedure for Hirschsprung's disease is a quick and easy adaptation of a well-described technique of transanal mucosectomy. Long-term follow-up will be required to determine whether bowel function is better that that seen after traditional staged repairs.  相似文献   
65.
Recent marketplace realities and trends have forced health care institutions to adopt strategic orientations that stress a customer focus. Central to such strategic orientations is the effective utilization of service quality practices and philosophies. Toward that end, this research offers health care institutions an affordable methodology. A real-life application of the rapid assessment methodology (RAM) in a health care operational setting is presented. Finally, a framework to guide the implementation of the RAM methodology is outlined and explored.  相似文献   
66.
67.
This article will review the current treatment of pediatric patients with diffuse pontine gliomas (DPG) and discuss three potential avenues of therapeutic research including (i) radiotherapy (RT) in combination with radiation sensitizers, (ii) dose-intensive, induction chemotherapy with hematopoietic support followed in sequence with RT applied as a consolidation therapy, and (iii) the interleafed application of phase-specific chemotherapeutic agents and hyperfractionated external beam radiotherapy (HFEBRT) referred to as chemoradiotherapy.  相似文献   
68.
Hegedus  V; Poulsen  PE; Reichardt  J 《Radiology》1978,126(1):29-34
A study of 11 patients with "double pylorus" revealed that a second channel between the gastric antrum and the duodenal bulb is the result of ulcer penetration. The fistula can be a sign of spontaneous recovery from ulcerative disease; the fistula occurred in conjunction with clinical improvement in the majority of the patients. The advantages of radiological vs. endoscopic diagnostic procedures are discussed.  相似文献   
69.
Five patients suffering from periodic affective disorders with short mood-cycles were treated with rubidium chloride, producing peak erythrocyte concentrations between 9 and 13 mmol/l. Loading with rubidium was associated with decreased total body potassium, but red-cell potassium was unchanged. Regular mood-cycling was disturbed, together with the associated body-weight changes. There was a slight extracellular "metabolic" acidosis. Electrolyte concentrations fluctuate abnormally in these patients, and two muscle biopsy specimens had very low potassium contents.  相似文献   
70.
A randomized, prospective clinical trial was performed to compare the Marco MT-336 automated perimeter with Goldmann-type manual kinetic perimetry. The number of true and false, positive and negative scotomas were counted, as determined by the findings on the Marco perimeter, assuming that the Goldmann perimeter was the "gold standard." For eight of the available programs, the accuracy specificity, sensitivity, positive predictive value and negative predictive value were determined. Chi-squared testing across and within programs was performed to determine the degree of agreement between the tests as to the presence or absence of scotomas. Additionally, McNemar's test was used to determine the amount of random disagreement between the two methods of testing. Although there are inherent difficulties in the analysis, the authors conclude that the Marco MT-336 perimeter is an accurate instrument for both detecting and ruling out the presence of visual field defects.  相似文献   
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