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With increasing budgetary restraints on the health system, it is apparent that the main contribution that radiology departments can make to significant cost reduction in hospitals is to decrease the length of time between requesting an X-ray examination and receiving the report (and images). Digital radiography (DR) was introduced into the Radiology Department at the Royal Adelaide Hospital as a pilot project to research the cost–benefits and efficiency of the system, and to determine future directions for planning a digital department. The business plan developed prior to implementation of this pilot project predicted a saving of one bed-day per inpatient when a fully digital department with a picture archiving and communication system (PACS) is installed. This initial study comparing DR and conventional radiography (convR) provides baseline data and shows encouraging results for more rapid transmission of reports to clinicians.  相似文献   
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Relaxation decreases large-airway but not small-airway asthma   总被引:3,自引:1,他引:3  
Eleven asthmatic subjects were each offered sixteen sessions of relaxation therapy, consisting of progressive relaxation, desensitization, and EMG biofeedback to the trapezius and frontalis areas, while 9 subjects were offered a complex placebo. Subjects in the relaxation condition showed greater improvement than subjects in the placebo condition in performance on a methacholine challenge test which, as a measure of airway reactivity, reflects degree of asthma. Subjects in both conditions showed improvements in various self-report measures of asthma symptoms and psychopathology. Subject in the relaxation condition reported a significantly greater decrease in frequency of emotional precursors to asthma attacks than subjects in the control condition. Overall improvement on the methacholine challenge test was predicted almost perfectly by heliox spirometry. Only subjects showing predominant large-airway obstruction obstruction improved on the methacholine challenge test. The relative contribution of large airway obstruction to asthma was found to correlate with psychopathology.  相似文献   
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The Kheda project experience has shown that bio-environmentalcontrol of malaria is feasible, cost effective and ecologicallysound. It clearly brings out the need to consider health issuesat the planning stage of all developments. Bio-environmentalcontrol of malaria is suggested as the first line of attackfor the control of mosquitoes, malaria and other mosquito-bornediseases. Insecticides may be reserved for short-term use. Thiswill enable judicious and selective use of insecticides in solelyepidemic situations. The growing problem of resistance to insecticidesin mosquitoes as well as environmental pollution, can then besolved on a long term basis.  相似文献   
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Six normal and 16 neoplastic colorectal specimens were examined with 8.5-MHz ultrasound (US). An articulated system facilitated precise spatial correlation between US and histologic sections. Images were blindly interpreted and then compared with histologic results. All six normal specimen showed five distinct echo layers and were distinguished from neoplastic specimens by all the observers. The central echogenic layer, corresponding to the submucosa, is useful in determining the depth of origin of a neoplasm and the presence of submucosal invasion. US had an accuracy of 92.5% in demonstrating invasion of the submucosa and 77% for invasion of the muscularis externa. For mucosal neoplasms with invasion through the muscularis externa and extension into the subserosal tissues, nearly 90% of US interpretations were correct. High-frequency US may be useful in determining the depth of invasion of mucosal tumors with respect to the submucosa and in differentiating mucosal from extramural masses.  相似文献   
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Rholl  KS; Lee  JK; Ling  D; Sicard  GA; Griffith  RC; Freeman  M 《Radiology》1986,160(1):113-117
Findings of magnetic resonance (MR) imaging in acute renal rejection and acute tubular necrosis (ATN) were studied in dogs. On T1-weighted images, corticomedullary differentiation was absent in kidneys undergoing acute rejection. The loss of corticomedullary differentiation in these kidneys was secondary to a decrease in the relative signal intensity of the cortex, indicating prolongation of the T1 relaxation time of the cortex. In contrast, corticomedullary differentiation was preserved on T1-weighted images of autotransplanted kidneys and kidneys with ATN. MR imaging findings correlated with changes in water content in these three groups of kidneys. Kidneys undergoing acute rejection showed a marked increase in water content compared with kidneys in the other two groups. No change in fat content was found in any group.  相似文献   
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