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This study is a retrospective review using transthoracic echocardiography to assess the success of fenestration closure as well as residual right to left shunts in 35 patients who underwent Fontan fenestration closure in the catheterization laboratory. There is a high rate of closure of the Fontan fenestration; however, other residual right to left shunts are common.  相似文献   
104.
OBJECTIVES: A large series of patients with various forms of systemic vasculitis were evaluated to analyze the prevalence of progressive sensorineural hearing loss (PSNHL), its characteristics and evolution, and the effects of different therapies. METHODS: A total of 673 patients were questioned about the presence of subjective audiovestibular disturbances. Of those, 80 subjects complained of subjective audiological disturbances and underwent oto-rhino-laryngological and audiovestibular evaluation. Those patients with progressive hearing impairment were selected and studied carefully. RESULTS: A PSNHL was observed in 14 patients. The hearing loss was bilateral and asymmetrical in most subjects. It was usually sensorineural, with a cochlear lesion. Unsteadiness was the most frequent vestibular symptom and canal paresis or palsy was noted in most patients. Systemic corticosteroids and cyclophosphamide were useful treatments; in unresponsive patients, satisfactory results were obtained with methotrexate and plasma exchange. CONCLUSIONS: PSNHL is a rare complication of systemic vasculitis, but occasionally is one of the presenting symptoms. Its clinical evolution is variable, but timely clinical assessment and treatment can positively affect prognosis.  相似文献   
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In the past few years, there have been many exciting advances in the field of molecular programming, reaching a point where implementation of non-trivial systems, such as neural networks or switchable bistable networks, is a reality. Such systems require nonlinearity, be it through signal amplification, digitalization or the generation of autonomous dynamics such as oscillations. The biochemistry of DNA systems provides such mechanisms, but assembling them in a constructive manner is still a difficult and sometimes counterintuitive process. Moreover, realistic prediction of the actual evolution of concentrations over time requires a number of side reactions, such as leaks, cross-talks or competitive interactions, to be taken into account. In this case, the design of a system targeting a given function takes much trial and error before the correct architecture can be found. To speed up this process, we have created DNA Artificial Circuits Computer-Assisted Design (DACCAD), a computer-assisted design software that supports the construction of systems for the DNA toolbox. DACCAD is ultimately aimed to design actual in vitro implementations, which is made possible by building on the experimental knowledge available on the DNA toolbox. We illustrate its effectiveness by designing various systems, from Montagne et al.''s Oligator or Padirac et al.''s bistable system to new and complex networks, including a two-bit counter or a frequency divider as well as an example of very large system encoding the game Mastermind. In the process, we highlight a variety of behaviours, such as enzymatic saturation and load effect, which would be hard to handle or even predict with a simpler model. We also show that those mechanisms, while generally seen as detrimental, can be used in a positive way, as functional part of a design. Additionally, the number of parameters included in these simulations can be large, especially in the case of complex systems. For this reason, we included the possibility to use CMA-ES, a state-of-the-art optimization algorithm that will automatically evolve parameters chosen by the user to try to match a specified behaviour. Finally, because all possible functionality cannot be captured by a single software, DACCAD includes the possibility to export a system in the synthetic biology markup language, a widely used language for describing biological reaction systems. DACCAD can be downloaded online at http://www.yannick-rondelez.com/downloads/.  相似文献   
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An integrated Rough Set approach is proposed and implemented to discover the historical operating rules of a Sicilian irrigation purpose reservoir. Operating rules are derived by expressing monthly releases from the reservoir as functions of stored volume, inflow and release during a 35-years period. This is accomplished through the Rough Set approach as implemented in the Rose package and the use of some indices able to recognize and further screen out the effective rules used in water supply reservoir management. This approach represents a new mathematical tool quite different to classical fuzzy rule-based systems in the decision rules induction. Results show that the integrated Rough Set approach allows to individuate with acceptable reliability the real criteria used for the system management. Work carried out with equivalent contributions of the Authors. Project AQUATEC “Tecnologie Innovative di Controllo, Trattamento e Manutenzione per la Soluzione dell'Emergenza Acqua” funded by the Italian Ministry of Education, Research and Technological Development (PON 2000–2006).  相似文献   
108.
The change in site preference in NiAl(Ti,Cu) alloys with concentration is examined experimentally via ALCHEMI and theoretically using the Bozzolo-Ferrante-Smith (BFS) method for alloys. Results for the site occupancy of Ti and Cu additions as a function of concentration are determined experimentally for five alloys. These results are reproduced with large-scale BFS-based Monte Carlo atomistic simulations. The original set of five alloys is extended to 25 concentrations, which are modeled by means of the BFS method for alloys, showing in more detail the compositional range over which major changes in behavior occur. A simple but powerful approach based on the definition of atomic local environments also is introduced to describe energetically the interactions between the various elements and therefore to explain the observed behavior.  相似文献   
109.
The Authors report a retrospective study of 46 cases of Hartmann's operation in order to analyze the changing indications to this procedure in the management of colo-rectal cancer. The Hartmann's is operation has been performed in 46 out of 723 patients (6.4%) with colorectal cancer treated surgically from 1973 to 1997. Data concerning the indications have been analyzed in two consecutive periods, from 1973 to 1985 and from 1986 to 1997, respectively. In the first period, the procedure has been performed in patients with neoplastic perforation (40% of Hartmann's cases), and in an elective basis in patients with locally invasive tumor or intra-abdominal metastasis (20%). Indications for the procedure in the period 1986-1997 have been locally invasive tumor and/or distant metastasis (52.8% of Hartmann's procedures), neoplastic perforation (22.2%), high surgical anaesthesiologic risk (22.2%) or intestinal obstruction (2.8%). In the second period it has been noted a decrease of the number of patients that underwent Hartmann's procedure for bowel obstruction, and an increase in the number of cases in which the operation was performed for neoplastic perforation, for local and/or distant diffusion, or for high surgical risk.  相似文献   
110.
Though they look very different, UOP SimulFlow™, Koch-Glitsch Ultra-Frac™, Jaeger CoFlo™ and Shell ConSep™ trays fall into the same category of trays using inertial separation technology. However, flooding mechanisms and the trends of entrainment and efficiency are different due to their different working principles. This paper provides a detailed analysis of these trays using available information from literature and U.S. Patents. Efforts are also made to interpret the observations reported. In terms of tray efficiency, it is found that SimulFlow, UltraFrac and CoFlo trays are typical point efficiency devices due to a completely mixed liquid pool on the tray deck, while ConSep trays can take advantage of liquid concentration gradient on the tray deck, which makes this tray at-tractive among all ultra high capacity trays.  相似文献   
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