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Forty-one patients with adrenal cortical tumors were evaluated retrospectively for the presence of histologic and non-histologic features associated with malignant behavior. The patients who survived operation were followed at least five years. The association of these features with subsequent metastasis was examined by both parametric and nonparametric statistical methods. Twelve criteria were statistically significant in predicting subsequent metastasis. The most significant of these were: clinical evidence of weight loss, broad fibrous bands traversing the tumor, a diffuse growth pattern, vascular invasion, tumor cell necrosis, and tumor mass. The tendency toward metastasis for each tumor was expressed in indices that correlated well with diagnoses made by conventional histologic means, but were more accurate in predicting subsequent clinical behavior than nonquantitative methods of evaluation.  相似文献   
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Urothelial carcinoma of the renal pelvis and ureter may develop as a manifestation of hereditary nonpolyposis colorectal cancer syndrome (HNPCC), a disorder characterized by mutation or inactivation of a number of DNA mismatch repair genes and detectable as microsatellite instability (MSI). Some urothelial carcinomas display areas of endophytic, or inverted, growth. In this study, urothelial cancers of the upper urinary tract (n = 132) from patients treated at 2 tertiary care centers were studied to identify an association between growth pattern and MSI. Thirty-five neoplasms were microsatellite unstable (26.5%), and MSI was more frequent in papillary lesions than in sessile urothelial cancers (P = .033). The amount of inverted growth was estimated as a percentage of the total tumor. The interobserver and intraobserver concordance in recognizing inverted growth was good, and 65.7% of microsatellite-unstable tumors exhibited at least 20% of an inverted growth component, compared with only 17.5% of microsatellite-stable tumors (P < .0001). In this series, inverted growth predicted MSI with a sensitivity and specificity of .82. Inverted growth in urothelial carcinomas of the upper urinary tract may serve as a marker lesion for MSI and may help identify patients who should be offered testing for HNPCC.  相似文献   
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The Epstein-Barr virus (EBV) is consistently associated with undifferentiated nasopharyngeal carcinoma (NPC). There is, however, conflicting evidence as to whether squamous cell NPCs are also EBV-associated. Moreover, it has been proposed that other epithelial tumours, particularly thymomas and thymic carcinomas, should be included in the group of EBV-associated neoplasias. However, since the viral DNA in these studies was demonstrated only in extracted DNA, the cellular origin of the viral DNA is uncertain. We have therefore investigated 152 epithelial tumours from various sites for the presence of EBV-DNA by in situ hybridization with 35S-labelled probes. Sixty-eight of 77 undifferentiated NPCs showed an EBV-specific autoradiographic signal, thus confirming the strong association of this tumour type with EBV even in geographical areas where undifferentiated NPC is not endemic. None of eight squamous cell NPCs showed an EBV-specific signal. All of 15 carcinomas with a similar morphology to undifferentiated NPC but from different anatomic sites (thymus, tonsil, breast) were EBV-negative as were 9 thymomas, 26 squamous cell carcinomas of the palatine tonsil, and 14 cervical carcinomas. Our results therefore suggest a unique association of EBV with undifferentiated NPC and support concepts assigning different biological properties to undifferentiated NPC as compared with squamous cell NPC.  相似文献   
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Although the popularization of the combined use of alcoholic beverages and energy drinks (ED) containing caffeine, taurine and other substances has increased, there are no controlled experimental studies on the effects of ED alone or combined with ethanol. This work aimed at evaluating the effects of different doses of ED combined or not with ethanol, on the locomotor activity of Swiss mice. The administration of 3.57, 10.71 or 17.86 ml/kg of ED alone increased the locomotor activity of the animals in relation to a control group. Low doses of ethanol (0.5, 1.0 and 1.5 g/kg) alone or in combination with 10.71 ml/kg of ED did not affect their locomotor activity. However, the reduction of activity observed after 2.5 g/kg of ethanol was antagonized by 10.71 ml/kg of ED. Further studies on the mechanisms of this interaction are still needed.  相似文献   
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Ohne ZusammenfassungVortrag gehalten vor der 105. Versammlung der Gesellschaft Deutscher Naturforscher und Ärzte, Heidelberg, Oktober 1968.  相似文献   
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