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11.
The aim of our study was to show the results of the Magnetic Resonance Angiography of pelvis and lower extremities. 21 patients with clinical signs of venous thrombosis were examined. The obtained results show the MRA is very useful in evaluation of venous flow.  相似文献   
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Enhancement of the basic properties of the X zeolite with FAU framework has been carried out during synthesis, without further treatment such as ion-exchange or impregnation. Control of the washing stage enables retention of the optimum amount of alkaline hydroxides, which increases the basic catalytic activity of X zeolite in the alkylation of toluene. This alkaline hydroxides neither affect the FAU framework nor the silicon/aluminium molar ratio of the X zeolite. The optimum (Na + K)/Al molar ratio of the improved catalyst was 1.06 corresponding to a washing volume of 200 mL. This X zeolite presented better catalytic activity than a cesium-zeolite prepared by ion-exchange. The presence of hydroxysodalite impurity in the X zeolite increased the amount of impregnated alkaline hydroxides but not the catalytic activity. The present study shows that it is possible to increase the basic properties of the X zeolite directly in the synthesis process.  相似文献   
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Pardo  A.  Merino  M.C.  López  M.D.  Escalera  M.D.  Viejo  F. 《Oxidation of Metals》2003,59(1-2):1-21
A study was made on the influence of the SiCp proportion and the matrix concentration of four composites (A360/SiC/10p, A360/SiC/20p, A380/SiC/10p, A380/SiC/20p) on their oxidation behavior. Gravimetric tests were used in a kinetics study of the corrosion process at different temperatures (350, 400, 450, and 500°C). The influence of corrosion on mechanical properties was evaluated by hardness measurements. The nature of corrosion products and the influence of the microstructure on the morphology and growth of the oxidation layer were analyzed by SEM and low-angle XRD. The extent of the damage due to oxidation for Al/SiCp composites increases with the SiCp concentration due to the increase of nucleation sites. One of these nucleation sites is in the interface region between the matrix and the particles. Oxidation was influenced more by the percentage of alloy elements in the matrix than by the proportion of SiCp reinforcement. The presence of Cu and Ni in the matrix favors the oxidation process through the formation of different intermetallic compounds.  相似文献   
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OBJECTIVE: a) To find the reasons for inadequate use of Hospital Casualty Departments (HCDs); b) to discover the general population's levels of information concerning non-hospital Emergency Services (NESs); c) to analyse the relationship between the type of Primary Care Centre (PCC), i.e. whether reformed or not, and inadequate use of HCDs. DESIGN: A crossover study. SETTING: The Germans Trias i Pujol Hospital Casualty Department, Badalona. PATIENTS: A random sample of 321 patients over 14 years old, who were attended for pathologies considered emergencies not requiring hospital treatment. MEASUREMENTS AND MAIN RESULTS: The variables gathered were: age, gender, where the patient came from, reason for hospital use, knowledge of NESs and subsequent referral. 83.2% of patients attended on their own initiative. The main reasons given were "advantages of a hospital" and "the persistence of symptoms." 49% of the patients stated they knew of the NESs. 80% of the patients proceeded from PCCs which had not been reformed. There were no statistically significant differences (p > 0.05) when the variables "reason for use" and "knowledge of NESs" were compared in relation to where the patient came from (i.e. reformed or non-reformed PCC). CONCLUSIONS: General practitioners in reformed PCCs are less likely to refer to HCDs. Knowledge and use of NESs should be actively supported.  相似文献   
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In spite of the names and works of practically all the early 19th Century Spanish specialists in urinary tract being widely known, there are still in my opinion several names and writings, either forgotten or misplaced in newspaper libraries, archives and general libraries, awaiting to be discovered. The second half of the 19th Century was a prolific age in every aspect of Spanish life, most particularly literature. In Medicine, apart from the well known professional writings, the number of scientific journals and publications, whether in the form of brochures or divulgative articles, that came to light was countless. Computer management of collections currently under implementation in many registers, will allow their location and the finding of new texts. One of these long forgotten pioneers, is Doctor Alejandro Settier (1858-1915), a Valencian practitioner who describes himself as a "disciple of the Paris hospitals and specialist in genitourinary tract disorders", who practised in Madrid between 1883 and 1890. Surprisingly, and in spite of him being the most prolific author in urological issues during the last century (my investigations show he is the author of 2 books, 3 brochures and 40 articles in journals), neither his name nor his work, as far as we know, are mentioned by none of the historians consulted, which is nothing but highly surprising if we also take into consideration that Alejandro Settier was the founder of the first Spanish monographic journal for urinary disorders: "Gaceta de enfermedades de los órganos génito-urinarios" (Gazette of genitourinary organs disorders), Madrid 1887, which in spite of its short existence, can be considered as the first scientific periodical publication in our specialty.  相似文献   
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In this paper we present Turk-2, a hybrid multi-modal chess player with a robot arm and a screen-based talking head. Turk-2 can not only play chess, but can see and hear the opponent, can talk to him and display emotions. We were interested to find out if a simple embodiment with human-like communication capabilities enhances the experience of playing chess against a computer. First, give an overview of the development road to multi-modal communication with computers. Then we motivate our research with a hybrid system, we introduce the architecture of Turk-2, we describe the human experiments and its evaluation. The results justify that multi-modal interaction makes game playing more engaging, enjoyable – and even more effective. These findings for a specific game situation provide yet another evidence of the power of human-like interaction in turning computer systems more attractive and easier to use.  相似文献   
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