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111.
BACKGROUND: The first results of a multicentric study dealing with recurrent varicose veins after surgery are presented. The aims of the study are: identifying the type of varicose vein, specifying the most frequent complaints (esthetical or functional), locating the causes of recurrence, establishing the causes and the most frequent seat of recurrence, clarifying whether it is enough to call recurrent all the varicose veins which appear after surgery or whether it is necessary to distinguish various typologies. METHODS: 194 patients (139 women and 55 men) aged 51.6 average (range 28-87), have been studied up to now with duplex and color scanner following a precise protocol which consisted of three stages: before treatment, within 2 months from treatment and after recurrence of varicose veins or venous insufficiency symptoms. RESULTS: Recurrent varicose veins represented 65.7%, residual ones 14.3%, new ones 2.5%. It has not been possible to identify the type of varicose vein in 8.3% of cases. Stripping of the great saphenous veins was carried out in 88% of cases, short stripping in 4.1%, stripping of the short saphenous veins in 6.9%. Recurrent varicose veins were due to technical error in 78.7% of cases, to diagnostic error in 9.2%, to unidentifiable causes in 12% of cases. CONCLUSIONS: Data relating to the prospective study of the research will be published in subsequent papers.  相似文献   
112.
The best operation condition on the field-reversed theta-pinch TC-I at UNICAMP is studied by analysis of the helium-plasma light emission and electromagnetic signals observed during the preionization and implosion phase of FRC plasma. The TC-I device can be operated with a crowbar switch on the preionization and main capacitor banks, in order to fix the number of oscillations as well as the time interval between the end of the preionization and the main discharge phase. A detailed study of the plasma implosion has been carried out by changing the above parameters and also the working gas pressure by using a photodiode, a visible spectrometer, magnetic probes, a Faraday cup and a streak camera.  相似文献   
113.
The Open Directory Project’s (www.dmoz.org/computers)1 goal is to produce the most comprehensive directory of the Web, by relying on a vast army of volunteer editors. Its computer security section is testimony to the success of this approach. There is no doubting that as the Web continues to grow exponentially, automated search engines are increasingly failing to return useful results to search queries. Site editors are grappling with a slippery slope in their attempts to keep up with submissions, resulting in a marked deterioration in the quality and comprehensiveness of their directories, link rot in fact being one of the main bug bears for the casual surfer and more serious researcher alike.  相似文献   
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Despite making up a significant proportion of airborne allergens, the relationship between fungal spores and asthma is not fully explored. Only 80 taxa of fungi have so far been observed to exacerbate respiratory presentations, with Cladosporium spp., Aspergillus spp., Penicillium spp., and Alternaria spp. found to comprise the predominant allergenic airborne spores. Fungal spores have been found in indoor environments, such as hospitals and housing due to poor ventilation. Meanwhile, outdoor fungal spores exhibit greater diversity, and higher abundance and have been associated with hospitalizations from acute asthma presentations. In addition, fungal spores may be the underlying, and perhaps the “missing link”, factor influencing the heightened rate of asthma presentations during epidemic thunderstorm asthma events. To improve our knowledge gap on fungal spores, airborne allergen monitoring must be improved to include not only dominant allergenic fungi but also provide real-time data to accurately and quickly warn the general public. Such data will help prevent future asthma exacerbations and thus save lives. In this review, we examine the health risks of prominent allergenic fungal taxa, the factors influencing spore dispersal and distribution, and why improvements should be made to current sampling methods for public health and wellbeing.  相似文献   
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