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71.
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An adult female presented with a painful recurrent swelling on the posterior aspect of the scalp of six months' duration, which was clinically diagnosed as fibroma. An excision biopsy showed anaplastic epithelial cells arranged in irregular cords and trabeculae, mitosis, malignant chondroid areas, desmoplasia and perineural invasion, suggesting malignancy. Wide excision of the tumor was the only treatment given since there was no metastasis.  相似文献   
73.
BACKGROUND: Although evidence-based medicine (EBM) has become widely accepted, the extent of its implementation during clinical clerkships is not well described. This study was done to characterize the implementation of formal EBM curricula in internal medicine clerkships. METHODS: In 1999, the Clerkship Directors in Internal Medicine surveyed its membership from 123 medical schools. The EBM section of the four-part survey addressed implementation, teaching and evaluation techniques, and barriers to implementing EBM. RESULTS: Survey response was 89%. Of 109 respondents, 38.5% reported having a formal EBM curriculum at some time during the third year and/or fourth year. Variability existed in curricular materials and evaluation tools used. The most common barriers to implementing EBM were lack of time and inadequately trained faculty. CONCLUSIONS: Evidence-based medicine has been formally incorporated into relatively few internal medicine clerkships. Faculty development programs in conjunction with innovative teaching methods may help overcome these barriers.  相似文献   
74.
ICD nocardiosis     
We present an initial report of Nocardia asteroides implantable cardioverter defibrillator infection. Systemic infection persisted despite pulse generator explant and several years of appropriate antibiotic therapy. Without epicardial lead system removal, chronic pleuropericardial disease developed.  相似文献   
75.
If parasite genotype influences the clinical course of malaria, we expect that isolates from patients with similar pathology would be more closely related than would be expected by chance. To explore this prediction, we typed nine microsatellite markers in sympatric Plasmodium falciparum isolates from cerebral and uncomplicated malaria patients from Vietnam. Temporal structure and linkage disequilibrium were also examined in this data set.  相似文献   
76.
The sodium-iodide symporter (NIS) is expressed by papillary (PTC) and follicular (FTC) thyroid carcinoma, and is essential for iodine uptake. We hypothesized that PTC and FTC with detectable NIS immunostaining would be more amenable to radioactive iodine ((131)I) treatment and follow a more benevolent course. To test this, we determined NIS expression by immunohistochemistry in 23 PTC, 9 FTC, and 12 benign thyroid lesions from children and adolescents. NIS expression was determined by two blinded examiners and graded as absent = 0, minimal = 1, moderate = 2, intense = 3, and very intense = 4. NIS was detected in 35% (eight of 23) of PTC, 44% (four of 9) of FTC, 25% (two of eight) of benign tumors, and 100% (four of four) of autoimmune lesions. The intensity of NIS expression was similar in PTC (0.61 +/- 0.24), FTC (0.56 +/- 0.24), and benign tumors (0.50 +/- 0.33) but was more intense in autoimmune lesions (3.0 +/- 0.7, p < 0.005). Distant metastases were found only among PTC with undetectable NIS (two of 15, 13%), and recurrence developed exclusively from PTC and FTC with undetectable NIS (four of 20, 20% versus zero of 12, p = 0.043). The dose of iodine 131 required to achieve remission in the five patients with PTC who had undetectable NIS (213.3 +/- 53 mCi) was greater than that required by patients with similar age and extent of disease for whom NIS expression is unknown (109 +/- 22 mCi, p = 0.06). We conclude that NIS expression is associated with a lower risk of recurrence for PTC and FTC of children and adolescents.  相似文献   
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Mitochondria (mt) play an important role in both apoptosis and haem synthesis. The present study was conducted to determine DNA mutations in mitochondrial encoded cytochrome c-oxidase I and II genes. Bone marrow (BM) biopsy and aspirate, peripheral blood (PB) and buccal smear samples were collected from 20 myelodysplastic syndrome (MDS) patients and 10 age-matched controls. Cytochrome c-oxidase I (CO I) and II (CO II) genes were amplified using polymerase chain reaction and sequenced. CO I mutations were found in 13/20 MDS patients and the CO II gene in 2/10 normal and 12/20 MDS samples, irrespective of MDS subtype. Mutations were substitutional, deletional and insertional. CO I mutations were most common at nucleotide positions 7264 (25%) and 7289 (15%), and CO II mutations were most common at nucleotide positions 7595 (40%) and 7594 (30%), suggesting the presence of potential 'hot-spots'. Mutations were not found in buccal smears of MDS patients and were significantly higher in MDS samples compared with age-matched controls in all cell fractions (P < 0.05), with bone marrow high-density fraction (BMHDF) showing a higher mutation rate than other fractions (P < 0.05). MDS marrows showed higher levels of apoptosis than normal controls (P < 0.05), and apoptosis in BMHDF was directly related to cytochrome c-oxidase I gene mutations (P < 0.05). Electron microscopy revealed apoptosis affecting all haematopoietic lineages with highly abnormal, iron-laden mitochondria. These results suggest a role for mt-DNA mutations in the excessive apoptosis and resulting cytopenias of MDS patients.  相似文献   
80.
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