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61.
Allon I  Vered M  Dayan D 《Oral oncology》2005,41(7):657-665
Liposarcoma (LS), one of the most common malignant tumors, is considered as a rarity in the oral cavity, the tongue being the most frequent site for its occurrence. The purpose of the present study was to review and analyze the clinico-pathologic correlations of 32 cases of LS of the tongue, including four new cases from the files of our department. A total of 32 cases of LS of the tongue were collected, 29 from a MEDLINE search of the English language literature (1966-2004). Since the histopathologic features of one of the four new cases have been presented previously, this case was counted only once. LS of the tongue is a tumor of adult and old age, with a mean age of approximately 62 years and a peak incidence in the seventh and eighth decades. Clinically, it is a long-standing tumor that commonly presents as a solitary nodular mass, but can also present as a multi-nodular lesion. The most common histopathologic type is that of atypical lipomatous tumor (ALT)/well-differentiated LS (75%). LS can be easily misdiagnosed with both benign and malignant lipomatous and non-lipomatous tumors. LS of the tongue was commonly treated by local excision, however, there were cases of (multiple) recurrences and dedifferentiation. When a lipomatous lesion is encountered in the oral cavity, and especially in the tongue, LS should certainly be among the lesions that top the list of differential diagnosis. The follow-up must be on a long-term basis since this tumor can recur years after initial surgical treatment and can also undergo dedifferentiation.  相似文献   
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Imaging the urinary tract in children has been mainly based on ultrasound (US) and intravenous pyelography (IVP), but these imaging modalities rarely show ectopic insertion of the ureter and the condition is often under diagnosed due to unusual clinical presentations. Recently newer magnetic resonance urography sequences have been developed that provide better delineation of the urinary tract. We report a 3-year-old girl presenting continuous dribbling of urine in which magnetic resonance urography revealed ectopic vaginal insertion of the ureter.  相似文献   
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PURPOSE: Penile endothelial function (EnF) is 1 of the major factors involved in the pathophysiology of erectile dysfunction. EnF assessment could offer crucial information on the etiology and degree of severity of cavernosal vascular pathology. In the present study we propose a new technique for the evaluation of penile EnF and test its applicability using strain gauge plethysmography. MATERIALS AND METHODS: A total of 23 healthy subjects (13 younger and 10 older than 40 years) with no history of erectile dysfunction were studied. The flow mediated dilation technique was applied to the arm and penis in both age groups for the assessment of EnF. Baseline blood flow and the sequential flow recordings after rapid cessation of 5 minutes of ischemia were obtained in both organs. RESULTS: Baseline flow in the penis was significantly higher (approximately 3-fold) than that in the forearm and was not affected by age in either organ. Both measures of penile EnF, ie area under the flow-time curve (AUC) and maximal flow obtained after ischemia were significantly lower in the older group compared to the younger group (p <0.01 and p <0.02, respectively). Individual penile AUC and maximal flow were significantly correlated with age (r = 0.55, p <0.01 and r = 0.50, p <0.02, respectively). Finally a positive, significant correlation existed between penile and forearm AUC (p <0.05, r = 0.48). CONCLUSIONS: The implementation of the flow mediated dilation technique using mercury strain gauge plethysmography is simple and applicable for the assessment of penile EnF. Endothelial function parameters in the penis were found to correlate with those in the forearm, thus support for the validity of the technique is given. Further strength for the validity of this procedure in the penis comes from the comparison between the forearm and penis, and the relation to subject age.  相似文献   
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It is well established that the conversion of PrP(C) to PrP(Sc) is the key event in prion disease biology. In addition, several lines of evidence suggest that glycosaminoglycans (GAGs) and in particular heparan sulfate (HS) may play a role in the PrP(C) to PrP(Sc) conversion process. It has been proposed that PrP(Sc) accumulation in prion diseases may induce aberrant activation of lysosomal activity, which has been shown to result in neurodegeneration in a number of diseases, especially lysosomal storage disorders. Among such diseases, only the ones resulting from defects in GAGs degradation are accompanied by secretion of large amounts of GAG metabolites in urine. In this work, we show that GAGs are secreted in the urine of prion-infected animals and humans, and surprisingly, also in the urine of mice ablated for the PrP gene. We hypothesize that both the presence of PrP(Sc) or the absence of PrP(C) may alter the metabolism of GAGs.  相似文献   
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