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Gradient-echo MR imaging: techniques and acronyms   总被引:3,自引:0,他引:3  
Elster  AD 《Radiology》1993,186(1):1
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BACKGROUND: Although a common dermatosis, idiopathic poikiloderma of the face and neck has not been studied in depth for decades. OBJECTIVES: To reassess the clinical and epidemiological characteristics of poikiloderma of Civatte (PC). MATERIAL AND METHODS: Fifty consecutive patients with PC. Evaluation included history taking and physical examination. Epidemiological and clinical parameters were recorded and analysed. The literature from 1923 until today, was reviewed thoroughly. RESULTS: The frequency of PC among dermatologic patients was estimated to be 1.4%. There were 34 females (68%) and 16 males in the present study. The mean age at diagnosis was 47.8 years for females and 61.7 years for males. The majority (88%) had skin phototype II or III. Among females, 26 were at their peri-menopausal stage, including three cases of iatrogenic menopause. Four patients reported that other blood-related family members also had PC. The v and the sides of the neck and the upper chest were most often affected in a symmetric distribution. The face (preauricular and parotid region) was involved in 19 patients (38%). The erythemato-telangiectatic clinical type predominated (58%), followed by the mixed (22%) and the pigmented type (20%). Almost half of the patients (46%) were symptomatic (itching, burning and 'flushing'). The mean duration from onset to diagnosis was 6.2 years according to the patients' report. The course was usually slowly progressive (82%) and irreversible. CONCLUSIONS: PC shows characteristic features, supporting the theory that it represents a distinct entity. It is rather common in Greece. Although menopausal women predominated in our cohort, men were not uncommonly affected and were diagnosed at an older age. Based on the predominating clinical feature, PC can be classified into three clinical forms. Symmetry and sparing of the anatomically shaded areas of the neck are highly characteristic for PC. Face involvement was not as common and as severe as it had been considered in the past. Recognition of clinical type is important for the selection of the most appropriate treatment, which, despite the advent of novel modalities, remains problematic.  相似文献   
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An 82-year-old man was admitted with a left hip fracture sustained in a fall. The fracture was surgically repaired. Ipsilateral leg swelling developed over the following 2 weeks. A lower extremity venous duplex scan demonstrated isolated dilatation of the popliteal veins in both lower extremities. Chronic thrombosis was noted in both popliteal veins at the level of this dilatation. Initial duplex scanning also revealed acute thrombus in the left popliteal, posterior tibial, and peroneal veins. A repeat scan 1 week later identified propagation of thrombus into the superficial femoral vein. Popliteal vein aneurysms, although rare, can cause significant morbidity and mortality. The literature is also reviewed.Presented at the Second Annual Winter Meeting of the Peripheral Vascular Surgery Society, Breckenridge, Colo., January 25–27, 1992.  相似文献   
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Twenty-four hours after intraperitoneal injection of cyclophosphane (40 mg/kg) and dioxydine (300 mg/kg) to C57Bl/6 mice, liver catalase activity dropped by 29 and 23%, respectively. In BALB/c mice, dioxydine (but not cyclophosphane) reduced catalase activity by 24%. Superoxide dismutase activity was lowered by cyclophosphane (but not dioxydine) in BALB/c mice, and by both dioxydine and cyclophosphane in C57Bl/6 mice (by 24 and 86%, respectively). The level of 2-thiobarbituric acid (TBA)-reactive lipid peroxidation (LPO) products in the liver of BALB/c mice treated with cyclophosphane and dioxydine increased 1.4- and 2.1-fold, respectively, while in C57Bl/6 mice it did not differ from the control. The initial rate ofin vitro-induced LPO in BALB/c mice receiving cyclophosphane and dioxydine increased 1.5- and 4-fold, respectively. In C57Bl/6 mice both cyclophosphane and dioxydine inhibited the accumulation of TBA-reactive LPO products. On the whole, animals of the C57Bl/6 strain are more resistant to the LPO-inducing action of mutagens than BALB/c mice, despite the fact that the latter are characterized by a higher activity of antioxidant enzymes. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, No. 5, pp. 528–532, May, 1996  相似文献   
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