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BACKGROUND AND OBJECTIVES: To evaluate the experience with laparoscopic nephrectomy in a large county hospital and perform a cost comparison between uncomplicated open and laparoscopic nephrectomy. METHODS: Eleven consecutive patients who underwent an uncomplicated laparoscopic nephrectomy in a large county hospital were compared with 8 patients who underwent uncomplicated open nephrectomy during the same period. Patient charts and corresponding billing records were reviewed to determine overall hospitalization cost and individual cost components. RESULTS: No perioperative complications occurred in either the laparoscopic or open group, and no statistically significant differences existed between groups with regard to patient demographics or operative parameters. The overall operating room costs favored the open nephrectomy group by dollars 1070 (P=0.003). However, the overall cost of hospitalization, surgeon professional fees, duration of hospitalization, room and board costs, laboratory, and radiology costs, pharmacy costs, intravenous solution and infusion pump costs all significantly favored the laparoscopic patient group. The mean difference in overall hospital cost between laparoscopic and open nephrectomy was dollars 1211 in favor of laparoscopy (P=0.037). CONCLUSIONS: Our experience with laparoscopic nephrectomy in a large county hospital demonstrates a clear economic advantage in favor of the laparoscopic approach. Given limited funding for public hospitals and a clear patient benefit, laparoscopic nephrectomy should constitute first-line therapy when nephrectomy is indicated.  相似文献   
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Background  

Simultaneous dual-radionuclide technetium 99m/thallium 201 scintigraphy can potentially produce perfectly aligned stress and rest images in less time than conventional protocols. However, interradionuclide crossover limits diagnostic accuracy. Accordingly, we evaluated99mTc and201Tl crossover in line and heart phantoms.  相似文献   
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1. The present study investigated the effect of prior administration of nifedipine on AVP-induced ACTH release in seven normal volunteers. Three protocols were used: 20 mg oral nifedipine; 0.14 pressor units intramuscular (i.m.) per kg bodyweight aqueous AVP; oral nifedipine plus i.m. AVP 90 min later. Plasma ACTH and cortisol were measured at intervals for 2.5 h during each test. 2. The mean peak plasma ACTH and cortisol levels and the mean peak changes from basal in these levels were significantly lower in the nifedipine/AVP test than in the AVP alone test. The integrated area under the cortisol time curve was significantly lower for the nifedipine/AVP test than that for the AVP test alone. Nifedipine alone caused no changes in ACTH or cortisol. 3. Acute administration of oral nifedipine caused an inhibition of AVP-stimulated ACTH and cortisol release in normal humans. This effect may be due to blockade of plasma membrane calcium channels normally activated during AVP stimulation of pituitary corticotrophs.  相似文献   
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Multislice proton MR spectroscopic images (SI) of the brain were quantitated, using the phantom replacement technique. In 16 normal volunteers, ranging in age from 5 to 74 years, average “whole brain” concentrations of choline (Cho), creatine (Cr), and N-acetylaspartate (NAA) were found to be 2.4 ± 0.4, 7.9 ± 1.3, and 11.8 ± 1.0 (mM, mean ± SD), respectively. These values are in good general agreement with those previously determined by single-voxel localization techniques. Cortical gray matter was found to have lower Cho and NAA levels, compared to those of white matter, corpus callosum, and basal ganglia. Cho was also found to increase significantly with age in several locations. Quantitative multislice proton SI is feasible in the clinical environment, and regional and age-dependent variations occur that must be accounted for when evaluating spectra from pathological conditions.  相似文献   
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