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1.
Ruggieri  PM; Laub  GA; Masaryk  TJ; Modic  MT 《Radiology》1989,171(3):785-791
The technique and feasibility of magnetic resonance (MR) angiography of intracranial vessels were studied in 35 healthy volunteers. Variations in image orientation, repetition time (TR), and flip angle were evaluated to determine their effects on flow-related enhancement. Gradient modifications--including echo time (TE), motion compensation, bandwidth, and field of view--were also studied in an effort to reduce motion-induced phase shifts. Results indicated that a FISP (fast imaging with steady precession) sequence with a TR of 50 msec, TE of 15 msec, velocity compensation in the read and section-select directions, acceleration compensation in the read direction, anisotropic volume, and a 1.25-mm partition thickness produced three-dimensional angiographic MR images that were accurate and reproducible in the depiction of the major intracranial vessels. Difficulties with field of view, persistent signal void secondary to higher-order motion, and spatial resolution remain major problems requiring additional study.  相似文献   
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Paediatric dacryocystorhinostomy   总被引:1,自引:0,他引:1  
Of 258 cases of dacryocystorhinostomy performed on children in the period September 1981 to September 1991, 130 were for simple, unresolved congenital nasolacrimal duct obstruction. Other indications for surgery included punctal agenesis, lacrimal fistula, post-traumatic and post-inflammatory canalicular obstruction. Of 177 children without canalicular pathology, 171 (96%) were relieved of symptoms with one operation, without canalicular intubation. Of 81 cases with canalicular disease, 55 of 70 (79%) who underwent DCR plus canalicular intubation, and 10 of 11 who underwent DCR plus Lester-Jones tube, were substantially improved with one operation. No child required peroperative or postoperative blood transfusion. Dacryocystorhinostomy in childhood, in experienced surgical hands, is a safe procedure, achieving relief of symptoms in most cases, particularly in the absence of canalicular disease.  相似文献   
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Factors influencing women to undergo screening mammography   总被引:2,自引:0,他引:2  
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The paper describes output measures of performance of the WesternAustralian Health Promotion Foundation (Healthway), using asystem known as graduated project evaluation (GPE). Resultsare reported at the basic and process levels of evaluation on588 health and sponsorship projects, and at the impact levelbased on surveys of 5710 spectators and participants at 53 sport,arts and racing events sponsored by Healthway funds. At thebasic and process levels the average Healthway project reached7449 people directly and generated media coverage of healthmessages on 27.3 occasions. It secured, on average, 0.99 healthystructural reforms in recreational or cultural venues, involvedthe participation of local community members in project administrationin 38% of instances, and provided 1596 person-hours of healtheducation. Non-smoking, safe drinking, nutrition, exercise,sun protection, safe sex and injury prevention health messageswere promoted using 24 different types of sponsor benefits.Of the 5710 respondents surveyed post-event, 67% were awareof the promoted health message and 82% of these understood whatthe message meant. Four per cent of all respondents intendedto take action ranging from seeking information to adoptingthe health behaviour. A comparison of the cost-effectivenessof small and large sponsorship projects is given to illustratethe use of GPE to inform funding decisions. Smaller projectsoutperformed larger projects on all available indicators. Wediscuss the peculiar features of the health promotion foundationconcept, methods to improve its performance and implicationsfor future research.  相似文献   
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