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31.
INTRODUCTION: Primary epilepsy of reading is a rare syndrome in which patients present with mandibular myoclonia when reading texts. Seizures are also frequently provoked by other stimuli. Occasionally they may be followed by generalized tonic-clonic seizures. CLINICAL CASES: We present the clinical features and electroencephalographs of three patients with epilepsy of reading, one of them also had seizures when playing chess and after doing arithmetic and the third after reading music. Treatment with valproic acid and clonazepam completely controlled the seizures in all three patients. In two cases we saw epileptiform activity on EEG whilst they were reading, although the basal EEG was normal. CONCLUSIONS: We believe that epilepsy of reading is under-diagnosed and emphasize the importance of careful questioning of epileptic patients as to factors which may precipitate the seizures. In view of the social problems which may arise, early recognition of the syndrome is important for the patient.  相似文献   
32.
The incidence of right aneurysms of the innominate or subclavian arteries is not very high. The majority of these aneurysms is placed in the distal segment of subclavian arteries. These aneurysms are involved in the complex of the thoracic outlet compressive neurovascular syndrome, especially in occurrence of the cervical rib. All aneurysms in this region can rupture and embolize. This is the main purpose of surgical management of this clinical entity. The aim of this study is to refer an interesting case history of a relatively young patient with a right aneurysm of the middle portion of left subclavian artery. The patient had no known vascular risks and the aneurysm was asymptomatic, the only sign was the visible and palpable pulsating mass over the left clavicle. The aneurysms of the middle and central portion of the left subclavian artery are usually explored through the left high posterolateral thoracotomy. The authors refer their experience with the use of a modified technique of exposure--supraclavicular (or transclavicular) incision with the subperiostal resection of the medial portion of the clavicle. This approach affords excellent exposure and a safe surgical procedure. This approach has been described in 1988 by H. Machleder. The advantage of this approach is a diminished risk of surgery in comparison with the transthoracic approach. The authors suppose, however, that it can be useful in traumatic or occlusive lesions, as well.  相似文献   
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Studies on computing systems making use of data bases have produced various notations to represent “schemata” of relations between data. These notations use graphs both as a tool to describe features relevant to applications and as an effective method of teaching. However, a critical limit may be the fact that they handle in different ways the concepts relevant to data and those relevant to programs. As a matter of fact, the ways of handling concepts relevant to programs are often unsuitable. For example, note that an answer to easy requests may require fairly complex programs. This paper introduces a uniform notation both for data-base schemata and for a class of application programs. This is accomplished by associating a suitable interpretation with bipartite graphs.  相似文献   
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Depolarization (XPD) data at 11.6 GHz in circular polarization collected during the SIRIO experiment on the Italian stations of Fucino and Lario are presented and analyzed. The obtained results are presented both in conditional form (i.e., XPD statistics conditioned to the co-polar attenuation (CPA)) and in "equiprobable" form (i.e., by comparing XPD-CPA values exceeded for the same fraction of the total observation time). The conditional XPD appears spread in an interval ofpm5dB around the conditional median value. This latter appears to be very close to the "equiprobable" value. The International Radio Consultative Committee (CCIR) procedure giving the "equiprobable" XPD appears fairly well supported by the Fucino data, while the Lario data give higher depolarization than predicted by CCIR.  相似文献   
35.
The results of a campaign of attenuation measurements carried out by means of the Italian satellite SIRIO at the two frequencies 11.6 and 17.8 GHz are presented. The campaign lasted five years (1978- 1982) and yielded almost continuous measurements at the lower frequency (acquired in three Italian stations) and measurements for a considerable fraction of time at the higher one (acquired in two of the three stations). The major aim of these measurements was to acquire long-term statistics to be employed in future earth-space radiolink design. This objective has been fully accomplished, owing to the very long life of the satellite, and the acquired data have been already utilized, properly extrapolated in frequency, for designing the domestic satellite system Italsat planned to start in 1987. Year-to-year and site-to-site variation have been found to be very high. Conversely the ratio between equiprobable values of attenuation at the two frequencies has proved to be very similar in the two stations and rather stable across the attenuation range.  相似文献   
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In this paper we present Top Tom, a digital platform whose goal is to provide analytical and visual solutions for the exploration of a dynamic corpus of user‐generated messages and media articles, with the aim of i) distilling the information from thousands of documents in a low‐dimensional space of explainable topics, ii) cluster them in a hierarchical fashion while allowing to drill down to details and stories as constituents of the topics, iii) spotting trends and anomalies. Top Tom implements a batch processing pipeline able to run both in near‐real time with time stamped data from streaming sources and on historical data with a temporal dimension in a cold start mode. The resulting output unfolds along three main axes: time, volume and semantic similarity (i.e. topic hierarchical aggregation). To allow the browsing of data in a multiscale fashion and the identification of anomalous behaviors, three visual metaphors were adopted from biological and medical fields to design visualizations, i.e. the flowing of particles in a coherent stream, tomographic cross sectioning and contrast‐like analysis of biological tissues. The platform interface is composed by three main visualizations with coherent and smooth navigation interactions: calendar view, flow view, and temporal cut view. The integration of these three visual models with the multiscale analytic pipeline proposes a novel system for the identification and exploration of topics from unstructured texts. We evaluated the system using a collection of documents about the emerging opioid epidemics in the United States.  相似文献   
40.
Despite of the development of advanced segmentation techniques, achieving accurate and reproducible gross tumor volume (GTV) segmentation results is still an important challenge in neuro-radiosurgery. Nowadays, magnetic resonance imaging (MRI) is the most prominent modality in radiation therapy for soft-tissue anatomical districts. Gamma Knife stereotactic neuro-radiosurgery is a minimally invasive technology for dealing with inaccessible or insufficiently treated tumors with traditional surgery or radiotherapy. During a treatment planning phase, the GTV is generally contoured by experienced neurosurgeons and radiation oncologists using fully manual segmentation procedures on MR images. Unfortunately, this operative methodology is definitely time-expensive and operator-dependent. Delineation result repeatability, in terms of both intra- and inter-operator reliability, can be achieved only by using computer-assisted approaches. In this paper a novel semi-automatic seeded image segmentation method, based on a cellular automata model, for MRI brain cancer detection and delineation is proposed. This approach, called GTVcut, employs an adaptive seed selection strategy and helps to segment the GTV, by identifying the target volume to be treated using the Gamma Knife device. The accuracy of GTVcut was evaluated on a dataset composed of 32 brain cancers, using both spatial overlap-based and distance-based metrics. The achieved experimental results are very reproducible, showing the effectiveness and the clinical feasibility of the proposed approach.  相似文献   
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