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941.
BACKGROUND: Roxatidine acetate is a novel H2-receptor antagonist and several studies have shown that it is effective in healing duodenal ulcers. We evaluated the efficacy of roxatidine in a non-western society with particular different features and its healing of duodenal ulcers was compared in Thailand with that of ranitidine. METHOD: The design was controlled, randomized, double-blind, and multicenter. The study recruited a total of 215 patients who were endoscoped at the start of the trial and then randomized to receive a single capsule of roxatidine acetate, 150 mg, or an identical capsule containing ranitidine, 300 mg, both to be taken at night. Patients were evaluated at 1, 2, and 4 weeks, including endoscopy at the last session, as well as at 6 weeks with repeat endoscopy if the ulcer had not healed. RESULT: Both drugs relieved pain rapidly, usually within a week, and at repeat endoscopy at 4 weeks most ulcers (78%) were healed, 77.0 and 79.5 per cent in ranitidine and roxatidine, and in those patients in whom healing was not completed the healing rate had risen appreciably to 89.8 and 93.8 per cent respectively at 6 weeks. Small ulcers tended to heal quicker than larger ones, but smoking and alcohol intake had no negative effects on the results. CONCLUSION: The study was valid proof that roxatidine, in a single evening dose of 150 mg, was found to be both safe and effective in the rapid healing of duodenal ulcers when compared with 300 mg ranitidine.  相似文献   
942.
943.
Model-based segmentation and analysis of brain images depends on anatomical knowledge which may be derived from conventional atlases. Classical anatomical atlases are based on the rigid spatial distribution provided by a single cadaver. Their use to segment internal anatomical brain structures in a high-resolution MR brain image does not provide any knowledge about the subject variability, and therefore they are not very efficient in analysis. The authors present a method to develop three-dimensional computerized composite models of brain structures to build a computerized anatomical atlas. The composite models are developed using the real MR brain images of human subjects which are registered through the principal axes transformation. The composite models provide probabilistic spatial distributions, which represent the variability of brain structures and can be easily updated for additional subjects. The authors demonstrate the use of such a composite model of ventricular structure to help segmentation of the ventricles and cerebrospinal fluid of MR brain images. Here, a composite model of ventricles using a set of 22 human subjects is developed and used in a model-based segmentation of ventricles, sulci, and white matter lesions. To illustrate the clinical usefulness, automatic volumetric measurements on ventricular size and cortical atrophy for an additional eight alcoholics and 10 normal subjects were made. The volumetric quantitative results indicated regional brain atrophy in chronic alcoholics  相似文献   
944.
945.
946.
Recent developments of stability control in mines, essentially based on Ge-doped fiber Bragg gratings (FBG) are reported including results about the different aspects of the system: accurate characterizations of FBG, sensor network topology and multiplexing method, user interface design and sensor packaging  相似文献   
947.
We investigate, analytically and numerically, stationary pulse propagation in n-core nonlinear fiber arrays of circular symmetry. It is shown that many types of stationary pulse-like solitary waves exist in these arrays. Transitions between the states of different symmetries occur in the form of bifurcations. The exact formula which specifies the points where asymmetric solutions bifurcate from the solution, which has identical pulses in each core, is obtained for the general n-core case. Energy-spatial frequency bifurcation diagrams are constructed for the lowest order soliton solutions for the n=3, 4, and 5 cases. The envelopes of these solutions and distributions of their field amplitude maxima among the cores are also presented  相似文献   
948.
949.
Layout-synthesis techniques for yield enhancement   总被引:1,自引:0,他引:1  
Several yield-enhancement techniques are proposed for the last two stages of VLSI design, i.e., topological/symbolic and physical layout synthesis. Our approach is based on modifications of the symbolic/physical layout to reduce the sensitivity of the design to random point defects without increasing the area, rather than fault tolerance techniques. A layout compaction algorithm is presented and the yield improvement results of some industrial layout examples are shown. This algorithm has been implemented in a commercial CAD framework. Some routing techniques for wire length and via minimization are presented, and the results of wire length reduction in benchmark routing examples are shown. We demonstrate through topological optimization for PLA-based designs that yield enhancement can be applied even at a higher level of design abstraction. Experimental results show that it is possible to achieve significant yield improvements without increasing the layout area by applying the proposed techniques during layout synthesis  相似文献   
950.
The authors present results for the likely capacity improvement when an adaptive multibeam antenna is used in conjunction with air interface parameters, as with the DCS1800 system. An analysis is made of the possible capacity enhancement while taking into account parameters such as power control, radio channel characteristics and different frequency reuse patterns. The results show that a substantial capacity improvement can be achieved with adaptive antennas, and also highlight the sensitivity of the capacity to operational parameters  相似文献   
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