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BACKGROUND: Dermatofibrosarcoma protuberans (DFSP) is a rare malignant tumour of the skin, with an estimated incidence of 0.8 to five cases per 1 million people per year. OBJECTIVE: To study epidemiological, immunohistochemical and clinical features, delay in diagnosis, type of treatment and outcome of DFSP from 1982 to 2002. METHODS: Using data from the population-based cancer registry, 66 patients with pathologically proved DFSP were included (fibrosarcomatous DFSP were excluded). Each patient lived in one of the four departments of Franche-Comté (overall population of 1 million people) at the time of diagnosis. The main data sources came from public and private pathology laboratories and medical records. The rules of the International Agency for Research on Cancer were applied. RESULTS: The estimated incidence of DFSP in Franche-Comté was about three new cases per 1 million people per year. Male patients were affected 1.2 times as often as female patients were. The trunk (45%) followed by the proximal extremities (38%) were the most frequent locations. DFSP occurred mainly in young adults between 20 and 39 years of age. Mean age at diagnosis was 43 years, and the mean delay in diagnosis was 10.08 years. Our 66 patients initially underwent a radical local excision. Among them, 27% experienced one or more local recurrences during 9.6 years of follow-up. There was one regional lymph node recurrence without visceral metastases. These recurrences were significantly related to the initial peripheral resection margins. We observed a local recurrence rate of 47% for margins less than 3 cm, vs. only 7% for margins ranging from 3 to 5 cm [P=0.004; OR=0.229 (95%, CI=0.103-0.510)]. The mean time to a first local recurrence was 2.65 years. Nevertheless, there was no death due to the DFSP course at the end of the follow-up, and the final outcome was favourable. CONCLUSION: Our study emphasizes the importance of wide local excision with margins of at least 3 cm in order to prevent local recurrence. However, the recent development of inhibitors of signal transduction by the PDGFB pathway should soon modify the surgical strategy, which is often too mutilating.  相似文献   
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Memory performance of elderly patients in the early stages of Alzheimer's disease (DAT) was compared with that of elderly control subjects. In explicit tests of recognition memory, which involve conscious recollection, the DAT patients were grossly impaired. In implicit tests of anagram solution and wordstem completion, which do not require conscious recollection, the DAT patients were not impaired. These findings further support the idea that a separate memory system, episodic memory, underlies conscious recollection, that it is this system which is most commonly damaged in amnesia, and that memory systems not involving conscious recollection may be spared in the early stages of Alzheimer's disease.  相似文献   
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Restriction maps of the rDNA cistron of twelve species of mosquitoes in six genera of the subfamily Culicinae were constructed using eight 6 bp recognition restriction enzymes. Anopheles albimanus was used as an outgroup. The size of the rDNA cistron ranged from 8.5 kb in Aedes katherinensis to 12.9 kb in Ae. polynesiensis. A total of twenty-six sites were scored; eighteen were polymorphic among ingroup taxa. The proportion of polymorphic nucleotide sites (Pnuc) was 0.059 and the heterozygosity per nucleotide site (Hnuc) was 0.028. Wagner and Fitch Parsimony, Dollo Parsimony and Nei-Li distance/neighbour-joining methods were used to construct phylogenetic trees. The rDNA RFLP dataset did not provide a well-supported phylogeny among culicine taxa. The RFLP phylogenies are incongruent with the morphology character based and molecular phylogenies and derived relationships did not correspond with current taxonomic classifications. The lack of resolution was due to homoplasy arising from frequent independent loss or gain of restriction sites among unrelated taxa.  相似文献   
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Over the past decade, the unfortunate reality is that the income gap has widened between Canadian families. Educational outcomes are one of the key areas influenced by family incomes. Children from low-income families often start school already behind their peers who come from more affluent families, as shown in measures of school readiness. The incidence, depth, duration and timing of poverty all influence a child’s educational attainment, along with community characteristics and social networks. However, both Canadian and international interventions have shown that the effects of poverty can be reduced using sustainable interventions. Paediatricians and family doctors have many opportunities to influence readiness for school and educational success in primary care settings.  相似文献   
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Background: Ingestion of coins is a common clinical problem in children. Many of the coins are ferromagnetic and can be retrieved with the help of a magnet. We describe the use of a novel endoscopic accessory for removing ferromagnetic coins. Material and methods: Two magnet discs of 1.5 cm diameter were joined to a 200 cm steel wire of 0.75 mm thickness with a terminal 5 cm spring. A Teflon tube (160 cm, 7 F) was used along with this instrument as a sleeve. The use of this accessory was analyzed prospectively in subjects presenting with a history of coin ingestion. The time taken for removal of coins, complications during the procedure and failure rate was noted. Effect of the magnet on cardiac rhythm was also noted during the procedure. Results: A total of 55 children (mean age 5.1 ± 2.3 years) with coin ingestion presented over a period of 1 year. Forty‐four coins were ferromagnetic. All ferromagnetic coins were removed successfully. Mean time for removal was 68 ± 22 s. No complications were encountered. Conclusion: The novel magnetic instrument is precise, safe and quick for the removal of ferromagnetic coins under direct vision.  相似文献   
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Teratomas are true neoplasms composed of tissues from all three germinal layers and may exhibit variable levels of maturity. They have an unknown origin and eccentric microscopic appearance. Teratomas arising from the oral cavity are rare in the newborn; only 22 cases have been reported in the literature. We describe a female neonate with an oral teratoma originating from the tongue that was successfully treated with surgery.  相似文献   
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