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21.
Higher than expected film badge readings were obtained for radiologic technologists operating computed tomography scanners. The cause of the erroneous dose assignments was determined to be improper storage of the film packet in the console area. Since the filter holder was absent during exposure, the overestimation of photon energy resulted in an incorrect conversion from optical density to dose. Film badges and particularly the film packet should not be stored in controlled areas where the radiation levels are expected to be above background.  相似文献   
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Growth of specialization in graduate medical education   总被引:2,自引:0,他引:2  
Donini-Lenhoff FG  Hedrick HL 《JAMA》2000,284(10):1284-1289
Fred G. Donini-Lenhoff, MA; Hannah L. Hedrick, PhD

JAMA. 2000;284:1284-1289.

The growth of specialization in graduate medical education (GME) and physician practice continues at a rapid rate, generating increasing national attention. Although the major educational, accrediting, and certifying bodies have mechanisms for approving new areas of study and practice, the results of their efforts have not been consistently congruent. This article presents information about GME since the beginnings of its standardization and accreditation in the early 20th century, its growth during and following World War II, and the variations among accredited specialties and subspecialties, certificates, and self-designated practice areas that have resulted from this long period of unstructured growth.

  相似文献   

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A 26‐year‐old man with a history of heavy marijuana and minimal tobacco use was found to have extensive bilateral lung bullae and interstitial fibrosis, heavily infiltrated by pigmented macrophages. These features can be associated with marijuana smoking. The differential diagnoses in this patient are also discussed.  相似文献   
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PURPOSE: We hypothesized that obese adults with coronary heart disease, obstructive lung disease, or depression would report greater impairments in health-related quality of life owing to their angina, dyspnea, or depressive symptoms as compared with persons with normal body weight. METHODS: We analyzed cross-sectional data from the Ambulatory Care Quality Improvement Project, a multicenter study of veterans enrolled in general internal medicine clinics. Health-related quality of life was assessed using the Medical Outcomes Study Short Form-36, the Seattle Angina Questionnaire, the Seattle Obstructive Lung Disease Questionnaire, and the Hopkins Symptom Checklist for Depression. RESULTS: Compared with patients of normal weight (body mass index: 18.5 to 24.9 kg/m2), underweight patients (body mass index <18.5 kg/m2) reported health-related quality-of-life scores that were at least 5% lower (worse) in all 15 quality-of-life domains examined. Patients with class III obesity (body mass index > or =40 kg/m2) reported quality-of-life scores that were at least 5% lower than those of normal weight patients in eight domains. Scores of overweight patients (body mass index: 25 to 29.9 kg/m2) were higher (better) than those of normal weight patients in 11 domains. CONCLUSION: Body mass index was strongly associated with generic- and condition-specific health-related quality of life. Our results suggest that, when considering health-related quality-of-life outcomes among veterans, the optimal body mass index may be above the "normal" range. Further research should test the validity of the 1998 National Institutes of Health body mass index categories as predictors of health outcomes among veterans.  相似文献   
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Objective. Abnormalities of intestinal rotation (AIR) are seen in association with congenital heart disease and heterotaxy syndrome. The prevalence of these abnormalities and recommendations for management are unclear. Our objective was to determine the prevalence of screening for AIR by elective imaging among our group and prophylactic vs. emergent surgical intervention for AIR in patients with congenital heart disease and heterotaxy syndrome. Methods. From October 1988 through October 2000, we identified 74 patients with congenital heart disease and heterotaxy syndrome, 44 (59%) asplenia, 30 (41%) polysplenia. Abdominal imaging was performed in 34 patients (45%). Twenty-four (32%) were found to have AIR. Of 34 patients imaged, 22 (65%) were found to have AIR. Two patients not imaged were found to have AIR: one at autopsy, and the other, incidentally during other abdominal surgery. Because imaging was performed based on individual cardiologist’s practice style that did not change over the period of the study and rarely secondary to symptoms, it is likely that the prevalence of AIR in the patients that were not electively imaged would be similar. Results. There was no statistical difference in the presence of AIR between asplenic (34%[15/44]) and polysplenic (30%[9/30]) patients. Of the 22 patients imaged with AIR, 18 underwent Ladd procedure. Five of 12 imaged patients without AIR were found to have other significant gastrointestinal pathologies requiring intervention including gastrostomy tube placement for reflux (3), duodenal web (1), and biliary atresia (1). Of the 40 patients who were not pre-emptively imaged, none suffered acute obstruction solely secondary to AIR. However, in 2 patients intestinal obstruction was suspected and subsequently discovered by imaging and/or laparotomy due to other intestinal anomalies. Conclusions. AIR is common among patients with heterotaxy syndrome and congenital heart disease. We recommend that patients with congenital heart disease and heterotaxy syndrome have routine elective abdominal imaging of their gastrointestinal tract at birth as part of their evaluation.  相似文献   
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Purpose: To examine the developmental course of labial and alveolar manner of articulation contrasts, and to determine how that course may be different for typically developing (TD) children with cochlear implants (CI).

Method: Eight young adults, eight TD 5–8 year-old children, and seven 5–8 year-old children with CIs participated. Labial /ba/–/wa/ and alveolar /da/–/ja/ continua stimuli were presented, with each continuum consisting of nine synthetic stimuli varying in F2 and F3 transition duration. Participants were asked to label the stimuli as either a stop or glide, and responses were analysed for phonetic boundaries and slopes.

Result: For the /ba/–/wa/ contrast, children with CIs required longer transition durations compared to TD children or adults to cross from one phoneme category to another. The children with CIs demonstrated less confidence in labelling the stimuli (i.e. less steep slopes) than the TD children or the adults. For the /da/–/ja/ contrast, the children with CIs showed less steep slope values than adults.

Conclusion: These results suggest that there are differences in the way TD children and children with CIs develop and maintain phonetic categories, perhaps differences in phonetic representation or in linking acoustic and phonetic representations.  相似文献   

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