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541.
A case of sarcomatoid carcinoma of the skin 总被引:1,自引:0,他引:1
HS Inaloz†§ RS Ayyalaraju† PJA Holt† P Laidler‡ 《Journal of the European Academy of Dermatology and Venereology》2003,17(1):59-61
We describe the histological and immunocytochemical findings of an exophytic cutaneous tumour with mixed features of atypical fibroxanthoma (AFX) and basal cell carcinoma (BCC). A 73-year-old woman presented with a rapidly growing tumour measuring 35 mm in diameter and 10 mm in height on the left forearm. The tumour was excised and histology revealed a biphasic tumour with a pleomorphic spindle cell component and an associated tumour composed of discrete islands of atypical basaloid cells with peripheral palisading consistent with BCC. The two tumours merged into each other at one point. The spindle cell tumour showed a positive immunocytochemical reaction to fibrohistiocytic marker of KP-1 (CD68) and a negative immunocytochemical reaction to AE1/AE3, CAM5.2, S-100 and HMB-45, features consistent with AFX. Immunocytochemistry of the basaloid tumour showed a positive reaction to epithelial markers AE1/AE3 and CAM5.2, and a negative reaction to S-100, HMB-45 and KP-1 (CD68). To date, 15 cases of primary cutaneous carcinosarcoma have been reported in the literature. It has been postulated that these tumours may originate from undifferentiated progenitor cells capable of producing multiple cell lines. 相似文献
542.
The role of oxidants and antioxidants in psoriasis 总被引:6,自引:0,他引:6
M Yildirim† HS Inaloz‡ V Baysal† N Delibas§ 《Journal of the European Academy of Dermatology and Venereology》2003,17(1):34-36
BACKGROUND: Psoriasis vulgaris is a chronic inflammatory skin disease characterized by well-demarcated erythema and scaly plaques. The pathogenesis of psoriasis still remains unclear. An increased reactive oxygen species (ROS) and insufficient antioxidant activity have been determined in psoriatic lesions. AIM OF THE STUDY: To evaluate and compare superoxide dismutase (SOD) and glutathione peroxidase (GP) activity in erythrocytes, catalase (CAT) activityand malondialdehyde (MDA) levels in serum of subjects with psoriasis and controls as well as MDA levels in skin biopsies from both groups. STUDY POPULATION: Twenty-two psoriatic patients (12 women and ten men) and 22 (12 women and ten men) healthy controls were involved in this study. FINDINGS: Statistically significant decreased levels of erythrocyte SOD and GP activities were noted in psoriatic subjects. Furthermore, a statistically significant increased serum CAT activity was found in the psoriasis group. No statistically significant difference was found in the serum MDA levels in the two groups, however, statistically significant increased tissue levels of MDA were noted in the psoriasis group. CONCLUSIONS: Our results support the hypothesis of an imbalance in the oxidant-antioxidant system in psoriasis. 相似文献
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Massarente Débora B Domaneschi Carina Marques Heloísa HS Andrade Samantha B Goursand Daniela Antunes José LF 《BMC oral health》2011,11(1):1-7
Background
Information bias can occur in epidemiological studies and compromise scientific outcomes, especially when evaluating information given by a patient regarding their own health. The oral habits of children reported by their mothers are commonly used to evaluate tooth brushing practices and to estimate fluoride intake by children. The aim of the present study was to compare observed tooth-brushing habits of young children using fluoridated toothpaste with those reported by mothers.Methods
A sample of 201 mothers and their children (aged 24-48 months) from Montes Claros, Brazil, took part in a cross-sectional study. At day-care centres, the mothers answered a self-administered questionnaire on their child's tooth-brushing habits. The structured questionnaire had six items with two to three possible answers. An appointment was then made with each mother/child pair at day-care centres. The participants were asked to demonstrate the tooth-brushing practice as usually performed at home. A trained examiner observed and documented the procedure. Observed tooth brushing and that reported by mothers were compared for overall agreement using Cohen's Kappa coefficient and the McNemar test.Results
Cohen's Kappa values comparing mothers' reports and tooth brushing observed by the examiner ranged from poor-to-good (0.00-0.75). There were statistically significant differences between observed tooth brushing habits and those reported by mothers (p < 0.001). When observed by the examiner, the frequencies of dentifrice dispersed on all bristles (35.9%), children who brushed their teeth alone (33.8%) and those who did not rinse their mouths during brushing (42.0%) were higher than those reported by the mothers (12.1%, 18.9% and 6.5%, respectively; p < 0.001).Conclusions
In general, there was low agreement between observed tooth brushing and mothers' reports. Moreover, the different methods of estimation resulted in differences in the frequencies of tooth brushing habits, indicative of reporting bias. Data regarding children's tooth-brushing habits as reported by mothers should be considered with caution in epidemiological surveys on fluoridated dentifrice use and the risk of dental fluorosis. 相似文献545.
Carcinoma of the ampulla of Vater associated with annular pancreas is a rare entity. Only seven cases have been reported so far in the English literature. We herein report one such case in a 42-year-lady who presented with progressively increasing jaundice and pain in the upper abdomen for past 2 months. A magnetic resonance cholangiopancreaticography (MRCP) and MRI revealed an annular pancreas with an ampullary mass and a dilated CBD. An upper gastrointestinal endoscopic biopsy from the ampullary mass revealed a moderately differentiated adenocarcinoma. She was diagnosed as having annular pancreas with periampullary cancer that was subsequently confirmed at laparotomy. Histological examination confirmed a complete annular pancreas with a 2 cm × 2 cm moderately differentiated adenocarcinoma of the ampulla of Vater. The management, however, remains as in any case of periampullary malignancy. This highlights the importance that obstructive jaundice in an adult patient presenting with annular pancreas may be associated with a coexisting periampullary malignancy. 相似文献
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