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21.
The aim of this study was to explore undergraduate and postgraduate dental students' understanding of a good learning experience by using 'reflection on learning' as described by Schon. Four groups of Year 4 BDS students and one group of postgraduate students in dental public health took part in a series of focus group discussions. The responses were grouped into four broad themes (a) active, practical and positive learning; (b) interactive/together learning; (c) personal learning; (d) theory into practice. Six educational models of good learning proposed by the students are described.  相似文献   
22.
Summary Ependymomas, glial neoplasms usually arising in the posterior fossa or spinal cord, rarely metastasize outside the central nervous system. We have reviewed all 81 ependymomas evaluated at MSKCC between 1956–1989. Five (6.2%) had extraneural metastases (ENM). The primary tumor was in spinal cord in 3 patients and the cerebral hemisphere in 2. Two tumors were histologically anaplastic; 3 were histologically benign. The 5 patients were 3, 3, 3.5, 16 and 37 years old. Time from initial diagnosis to development of ENM was 0, 15, 35, 40, and 288 months. At the time of ENM the primary tumor was progressing in 4/5 patients. Prior therapy had included resection plus radiation therapy (RT) (1), RT plus chemotherapy (1), resection plus RT plus chemotherapy (2). One patient had not received prior therapy because ENM were present at diagnosis. The sites of ENM included lung and thoracic lymph nodes (2), pleura and peritoneum (2), and liver (1). Both patients with peritoneal ENM had had ventriculoperitoneal shunts. ENM did not correlate with histologic grade, age, or degree of surgical resection. When patients with ependymoma develop signs or symptoms of systemic disease such as abdominal pain, cough, or adenopathy, ENM should be considered.  相似文献   
23.
Osteoclastoma of the calvarial bone of membranous origin is a rare entity. This paper presents a case of osteoclastoma of the occipital bone and a brief review of literature.  相似文献   
24.
Ossifying fibroma of the sellar turcica is extremely rare. There are only sporadic case reports in the literature. One such case simulating pituitary adenoma is presented in an 18-year-old girl.  相似文献   
25.
A 20-yr-old black male was admitted with a 5-month history of profound weight loss and diarrhea. Appetite and dietary intake had been remarkably well preserved up until the week before admission. The severity of his depletion was evidenced by a body weight of only 38% of standard, multiple electrolyte deficiencies, and reduced metabolic expenditure, protein turnover, protein synthesis, and pancreatic function. Immunological defects included diminished lymphocyte numbers, lymphocyte transformation, gamma-globulin concentration, and cell-mediated immunity. A diagnosis of alpha-heavy chain disease (alpha-HCD) was made on endoscopic duodenal biopsy and serology--lymphoma being excluded by scanning and laparotomy. Treatment consisted initially of intravenous nutrition (because of the extreme malnutrition, severe diarrhea, and malabsorption of fluid, electrolytes, carbohydrates, and fat) and oral tetracycline. Response was dramatic, with a doubling of body weight within 6 wk, and resolution of malabsorption. He was discharged on a normal diet and long-term oral tetracycline (250 mg/day), and at 1-yr follow-up, nutritional status and gut function were normal despite persistence of duodenal mucosal abnormalities and markers of alpha-HCD and bacterial overgrowth. These results suggest that the malabsorption initially identified in this patient was not due simply to the mucosal abnormalities that characterize alpha-HCD, but was more a consequence of the superimposition of nutrient maldigestion and absorption resulting from the extreme state of protein deficiency and its effects on gut and pancreatic function.  相似文献   
26.
A series of 1,3,5-trisubstituted pyrazole mevalonolactones were prepared and evaluated for their ability to inhibit the enzyme HMG-CoA reductase in vitro. Since previous studies suggested that the 5-(4-fluorophenyl) and 3-(1-methylethyl) substituents afforded optimum potency, attention was focused on variations in position 1 of the pyrazole ring. Biological evaluation of analogues bearing a variety of 1-substituents suggested that, although most substituents were tolerated, none afforded an advantage over phenyl, which exhibited potency comparable to that of compactin in vitro.  相似文献   
27.
Soutter  J; Eccles  MP; Newton  J 《Family practice》1996,13(2):152-155
BACKGROUND: Partnerships have been investigated in different professions,but other than identifying problems, little work has been carriedout on general practice. OBJECTIVE: The aim of this present study was to develop methods for studyingpartnerships in general practice. METHOD: A tripartite methodological approach was used, with questionnairesadapted from other instruments in use in other professions,followed by an individual interview with each partner, and non-participantobservation at a partnership meeting. Results for one case-studypartnership are given. RESULTS: There were no major differences between the partners on alldimensions measured; the minor differences indicated by theresults of the questionnaires were corroborated by the partnerinterviews and observations. CONCLUSIONS: We conclude that the use of such techniques could provide supportto partnerships going through significant periods of change. Keywords. General practice, interview, observation, partnerships, questionnaire.  相似文献   
28.
29.
The thyroid     
The integument contains many components whose function is influenced by thyroid hormone. Thus, an increase or decrease in hormone levels results in a variety of cutaneous, hair, and nail changes. These changes are important to recognize, as they may aid in the early diagnosis of thyroid disorders. Other cutaneous disorders are more prevalent in patients with thyroid disease, and their recognition may likewise be helpful. Finally, several syndrome complexes occur with which thyroid disorders are regularly associated.  相似文献   
30.
Sensorineural hearing loss has not been previously reported in patients with the Marinesco-Sj?gren Syndrome. Two siblings are described where hearing was initially normal but subsequently deteriorated.  相似文献   
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