A case of a 38 year old male with WPW syndrome and frequently recurrent antidromic atrio-ventricular sustained tachycardias is presented. In his ecg recordings delta wave depolarizations indicated right free wall accessory pathway. This was proved during electrophysiologic study. The effective refractory period of this pathway was short in both directions-below 200 ms. There was a wide zone of sustained antidromic tachycardia 236-247/min induction. Intravenous injection of flecainide terminated antidromic tachycardia but a wide zone of sustained orthodromic tachycardia 150/min induction appeared. Dissection of the right free wall accessory pathway was performed using Sealy technique (Cox modification). During the intraoperation electrophysiologic study an orthodromic tachycardia with retrograde conduction through an antero-septal accessory pathway was induced. After dissection of that second pathway abnormal atrioventricular conduction was abolished. The patients has been free from episodes of tachycardia during one year follow-up period. 相似文献
The objective of this study was to analyze allogeneic lymphocyte proliferative responses to cultured human pancreatic islets after gene transfer of viral interleukin (IL)-10 to the islets using replication-defective adenoviral vector. Human islets, either whole or dispersed into single cells, were cocultured with adenovector containing an expression cassette encoding the viral IL-10 gene under control of an SV40 promoter, this sequence replacing viral E1A and part of E1B early viral protein sequences. Subsequent production of recombinant protein by islets was determined by ELISA, and was found dependent on the multiplicity of infection (or ratio of vector to target cells). Protein was secreted by transfected islets at high levels 3-7 days after gene transfer. At high multiplicity of infection (100:1), islet viability was normal, but insulin secretion in response to glucose stimulation was blunted by 50%. Low-level recombinant viral IL-10 secretion by the islets was associated with increased allogeneic lymphocyte proliferation in mixed islet lymphocyte reactions. At protein levels in islet supernatant above 5 ng/ml, lymphocyte proliferation was significantly reduced. This pattern of viral IL-10 effect on lymphocyte proliferation correlated well with mixed lymphocyte reaction assays using purified protein. We conclude that transferred cytokine sequences are secreted by transfected islets as a function of the initial vector inoculum. The functional effect of the secreted cytokine viral IL-10 on allogeneic lymphocyte proliferation is dose dependent. Low-level recombinant protein secretion tended to augment lymphocyte proliferation, whereas high-level secretion significantly down-regulates this response. 相似文献
Domains in continuous constraint programming are generally represented with intervals whose n-ary Cartesian product (box) approximates the solution space. In this article, we generalize this representation and propose a generic solver where other domains representations can be used. In this framework, we define a new representation for continuous domains based on octagons. We generalize local consistency and split to this octagon representation. Experimental results show promising performance improvements on several classical benchmarks. 相似文献
Orthogonal moments and their invariants to geometric transformations for gray-scale images are widely used in many pattern recognition and image processing applications. In this paper, we propose a new set of orthogonal polynomials called adapted Gegenbauer–Chebyshev polynomials (AGC). This new set is used as a basic function to define the orthogonal adapted Gegenbauer–Chebyshev moments (AGCMs). The rotation, scaling, and translation invariant property of (AGCMs) is derived and analyzed. We provide a novel series of feature vectors of images based on the adapted Gegenbauer–Chebyshev orthogonal moments invariants (AGCMIs). We practice a novel image classification system using the proposed feature vectors and the fuzzy k-means classifier. A series of experiments is performed to validate this new set of orthogonal moments and compare its performance with the existing orthogonal moments as Legendre invariants moments, the Gegenbauer and Tchebichef invariant moments using three different image databases: the MPEG7-CE Shape database, the Columbia Object Image Library (COIL-20) database and the ORL-faces database. The obtained results ensure the superiority of the proposed AGCMs over all existing moments in representation and recognition of the images.
Throughout the lifetime of nuclear facilities, radiological inspections are of vital importance, as controlling the radiological state of these facilities is necessary to ensure that their operations remain safe. These inspections are equally important during dismantling and decommissioning (D&D). Inspections of facilities that have contained radionuclides, particularly high activity cells, and very high activity cells are the first step when planning to carry out maintenance and D&D operations. Therefore, the development of investigation robots for hostile environments is a strategic approach in the nuclear field in order to meet these needs. The CEA and CYBERIA have worked together to develop the RICA robot (Robot d'Inspection pour Cellules Aveugles, or blind cell inspection robot), which can locate and measure the activity of radioactive sources. Since 2007, RICA is one of the strategic apparatuses that the CEA has been using for dismantling operations in its nuclear facilities. This small tracked robot was developed to offer a good level of modularity in terms of the onboard equipment able to carry out inspection and sampling missions in extremely hostile environments. To be able to do this, it can be operated either with a complete unit of radiological measurement tools or with a remote‐handling arm. The measurement unit consists of a gamma camera, a gamma spectrometer, and a dose rate detector. This innovative radiological measurement unit enables in situ activity quantification and the collection of all the information necessary to interpret the radiological spectra. On the other hand, when equipped with a remote‐handling arm, the unit can be used to carry out samplings, which will then be analyzed in a laboratory. This paper first presents the RICA robot, giving its main technical features. The innovative radiological measurement unit is described, explaining each of its bricks. The gamma irradiator tests that qualified the robot's functioning under irradiation are described, and the dose resistance results are analyzed. Lastly, examples of tasks in which RICA has been used in CEA nuclear facilities illustrate the robot's modularity. 相似文献
Symmetries abound in logically formulated problems where many axioms are universally quantified, as this is the case in equational
theories. Two complementary approaches have been used so far to dynamically tackle those symmetries: prediction and detection.
The best-known predictive symmetry elimination method is the least number heuristic (lnh). A more recent predictive method, the extended least number heuristic (xlnh), focuses first on the enumeration of a bijection in the problem and easily exploits in the sequel the remaining isomorphisms.
On the other hand, dynamic symmetry detection is costly in the general case (the problem is Graph Iso complete) but allows
one to exploit more symmetries, and efficient (polytime) yet incomplete detection algorithms can be used on each node. This
paper presents a generalization of xlnh that focuses on the enumeration of a unary function that does not require the function to be bijective, a general notion
of symmetry for finite-model search in first-order logic together with an efficient symmetry detection algorithm, and a function-ordering
heuristic that exploits the inherent structure of first-order logic theories to improve the search when using function-centric
methods. A comprehensive study of the compared efficiency of all methods, in isolation and in combination, demonstrates the
acceleration that can be expected in all cases. These ideas are implemented by using the known system SEM as an experimentation
framework, to allow for accurate comparisons. 相似文献
The most effective treatment for alcoholic liver disease is abstinence from alcohol and it is the only treatment for patients with alcoholic fatty liver. Although many empirical therapeutic agents have been studied in the short-term and long-term treatment of alcoholic hepatitis, results have been mainly inconclusive. To date, only corticosteroids have proved to decrease the short-term mortality rate of patients with severe forms of acute alcoholic hepatitis. Corticosteroids are not beneficial to the majority of patients with mild or moderate forms of acute alcoholic hepatitis; such patients improve with abstinence from alcohol and general supportive measures and do not need a specific short-term treatment. Most long-term trials have only showed that most patients with alcoholic liver disease were neither abstinent nor compliant, and that long-term survival was strongly correlated to abstinence from alcohol. In one study, propylthiouracil decreased the long-term mortality rate of compliant patients with severe alcoholic liver disease who reduced their alcohol intake; however, further clinical trials are needed before propylthiouracil can be recommended. In another study, colchicine decreased the long-term mortality rate of cirrhotic patients, 45% of whom had alcoholic cirrhosis. Results were highly significant, and the need for further clinical trials of colchicine in the long-term treatment of alcoholic and non-alcoholic cirrhosis is imperative. Enteral nutrition should also be studied in severely malnourished cirrhotic patients, since it was shown to decrease the short-term mortality rate of such patients in a recent study. 相似文献
Purpose of review The enthusiasm generated by the results of the Edmonton protocol of islet transplantation is inciting a great number of institutions to start such programs. However, the procedure of islet isolation and purification is costly, complex an 相似文献
Immunocytochemical techniques are confronted with the problem of obtaining adequate tissue preservation together with retention of protein antigenicity. Various methods, including freeze-drying and freeze-substitution, have been devised to circumvent this problem. In the present study, we report that microwave energy used in combination with low concentrations of glutaraldehyde (0.1%) and paraformaldehyde (2%) preserves the structural integrity of plant tissue and antigenicity of proteins. Tobacco leaf samples fixed in a time as brief as 15–20 s exhibited excellent preservation of fine structures. By contrast, specimens irradiated for shorter (5–10 s) or longer (30–40 s) periods showed poor morphological preservation. Microwave irradiation for 15–20 s was found useful for immobilizing large amounts of soluble antigens. The fast microwave fixation method was successfully used to preserve pathogenesis-related (PR) proteins, which were subsequently localized by a postembedding immunogold procedure. In addition to soluble antigens, cellulose subunits and pectic substances, two major plant cell wall components, were found to be highly preserved in microwave-irradiated tobacco plant tissue. The present study demonstrates that microwave fixation of plant tissue is a simple and inexpensive method that is easy to perform with commercially available microwave ovens. The incubation time for fixation is reduced from 2 h to 15–20 s without loss of fine structural details. This method will undoubtedly acquire increasing applicability and relevance in plant biology. 相似文献