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71.
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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外源性AA引起兔动脉条收缩,呈剂量依赖性;EPA抑制AA收缩血管亦呈浓度依赖性;DHA对AA收缩血管作用无明显影响。破坏血管内皮后AA收缩血管作用大为减弱,EPA抑制AA收缩血管作用也几乎消失。吲哚美辛能阻断AA收缩兔主动脉条的作用。兔主动脉6-keto-PGF、TXB2及其比值随AA浓度升高而增加,低剂量EPA对前列腺素类代谢无明显影响,较大剂量时则降低上述指标。  相似文献   
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铁皮石斛试管苗快速繁殖的研究   总被引:28,自引:0,他引:28  
兰科植物铁皮石斛(Dendrobium candidum Wall.ex Lind1.)的茎为常用名贵中药。多年来,主要依靠采收野生品种供药用和出口,致使野生资源枯竭,现已成为日益稀少的濒危植物。兰属种子和石斛属种子试管繁殖已积累不少资料,但是有关铁皮石斛种子试管繁殖的研究只有少量简单的报道,对其种子在试管繁殖过程中,所需外界条件的研究也不够  相似文献   
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