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951.
Cavernous hemangiomas: dipolar susceptibility artifacts at MR imaging   总被引:1,自引:0,他引:1  
  相似文献   
952.
A study was undertaken to evaluate a reflective practitioner model with midwives, who self-selected into the project when they were studying the Bachelor of Health Science (Nursing) unit NR278, Advanced Nursing Practice, Midwifery. The theoretical assumptions that influenced the research were those forwarded by Schon (1983) and Boud, Keogh and Walker (1985), who argued that practitioners are often unaware of the sophisticated knowledge they have regarding the intricacies of their practice, but that this personal knowledge can be made explicit through reflective processes. The aim of the study was to research the use of a distance education reflective practitioner process that encouraged midwives to examine their practice with a view to making changes where necessary. All the research objectives were met to some extent, although each experience of the research process was particular to the individual participant. Analysis consisted of: interpretation of the participant's insights into their individual experiences; the researcher's interpretations of participant's experiences; and collective themes arising out of the research. This paper concentrates mainly on the participant's insights into their individual experiences of practising midwifery, using a reflective practitioner model.  相似文献   
953.
Optic nerve dysfunction in thyroid eye disease: CT   总被引:3,自引:0,他引:3  
Barrett  L; Glatt  HJ; Burde  RM; Gado  MH 《Radiology》1988,167(2):503-507
Optic nerve dysfunction in thyroid eye disease is thought to be due to compression of the optic nerve by enlarged extraocular muscles near the orbital apex. High-resolution computed tomography (CT) scans of 78 orbits of 31 patients with thyroid eye disease were reviewed. Axial scans alone were inadequate for demonstrating compression of the optic nerve. With a coronal reformatted scan from the axial scans, a muscular index was devised and measured to reflect extraocular muscle impingement on the optic nerve. Orbits with optic nerve dysfunction had significantly higher muscular indices than those without optic nerve dysfunction, supporting the hypothesis that optic nerve dysfunction is usually secondary to compression by enlarged extraocular muscles. Muscular indices of 67% or greater in patients with optic nerve dysfunction were diagnostic of compressive optic neuropathy, while muscular indices of less than 50% appeared to exclude optic nerve compression. A single case of optic nerve dysfunction without muscular compression is also discussed.  相似文献   
954.
955.
Several new pyridones, pyrans, pyrazolo[4,3-b]pyrans and isoxazolo[4,3-b]pyrans were prepared from the chalcones 2a,b and activated methylene compounds.  相似文献   
956.
Several new isoxazole derivatives were prepared from the 5-aminoisoxazole derivatives 1 and the 3-aminoisoxazole derivative 12 as starting materials.  相似文献   
957.
Randel  SB; Gooding  GA; Clark  OH; Stein  RM; Winkler  B 《Radiology》1987,165(1):191-194
High-resolution (10-MHz) ultrasonography was performed in 181 patients with primary or secondary hyperparathyroidism during a 4-year period and evaluated retrospectively. Thirty-seven unusual-appearing parathyroid tumors were found among 235 parathyroid glands identified as abnormal. There was pathologic correlation in 36. The typical appearance of parathyroid adenoma was that of an oval hypoechoic or anechoic lesion in the neck, aligned in a craniocaudal direction and often posterior to the thyroid. Morphologic variations from the norm included giant size (n = 11) (4.6%), cystic changes in a solid tumor (n = 9) (3.8%), calcified glands (n = 6[in three patients]) (2.5%), a multilobulated configuration (n = 5) (2.1%), an inhomogeneous pattern (n = 5) (2.1%), and a parathyroid cyst (n = 1) (0.4%). Recognizing the abnormal parathyroid variants can increase the diagnostic accuracy of sonographic examination.  相似文献   
958.
Effect of contrast material dose on clinically evident change in renal function was studied prospectively in 200 examinations requiring intravenous or intraarterial administration of contrast material. All patients were adequately hydrated. Blood urea nitrogen and serum creatinine were measured before and after the procedure. Ionic and nonionic contrast agents were used. Total dose of contrast material ranged from 30 to 530 mL (mean, 237 mL). There was no tendency to give smaller doses to patients with preexisting renal impairment and no relationship between total dose and patient age. No consistent clinical effect on renal function was demonstrated with increasing dose, regardless of whether ionic or nonionic agents were used. In adequately hydrated low-risk patients with predominantly normal initial renal function and within the dose range studied, there does not appear to be any consistent clinical change in renal function with increasing contrast material dose.  相似文献   
959.
The patients registered with a general practice are usually spread over many censusareas and overlap with the distribution of neighbouring practices, so a validated method of aggregating census data to describe the characteristics of practice patients is required. Four methods were used to provide estimates of the percentage of patients aged 75 years and over from census data for 81 practices in Suffolk, England, and these were compared with values derived from the FHSA patient register. Census values for practice areas produced better estimates than those based on the location of the surgery, but the best methods were based on patient-weighted averages of ward and enumeration district data. The finer geographical detail of enumeration districts did not produce substantially more accurate estimates than the ward-level data: both gave estimates with limits of agreement within 2% of the patient register values. Errors in the census, errors in patient registers and selective geographical distributions of practice patients prevent close matching of census and register measures, but two of the methods tested produced estimates that allow broad comparisons between practices.  相似文献   
960.
Tumors of the bronchi: role of evaluation with CT   总被引:4,自引:0,他引:4  
Computed tomography (CT) was performed in 142 patients thought to have an endobronchial tumor based on clinical or radiologic grounds. In 121 patients an endobronchial mass was confirmed at bronchoscopy with biopsy or at surgery. The CT scans were evaluated independently by two experienced observers (A and B). For statistical purposes the result in each single bronchus from the level of the trachea to the segmental bronchi was considered separately. A total of 361 abnormal and 1,413 normal bronchi were confirmed with bronchoscopy or surgery. Observers A and B identified 100% and 99%, respectively, of the abnormal bronchi and 97% and 96%, respectively, of the normal bronchi on CT scans. For the standard CT examination (8-mm-thick sections) a sensitivity of 94% (observer A) or 91% (observer B) and a specificity of 99% (observers A and B) were found in the diagnosis of a normal or narrowed bronchial lumen. CT proved to be a reliable method for demonstrating tumor lesions of the bronchi.  相似文献   
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