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Two adult patients with the diagnosis of gastric lymphoma who developed adenocarcinoma of the stomach 8 years after the treatment are presented. Both patients were treated by subtotal gastrectomy followed by irradiation of 4,000–4,500 cGy to the epigastric region and six courses of chemotherapy (vincristine, cyclophosphamide, prednisolone). In our review of the literature, 16 cases of gastric adenocarcinoma following the treatment of gastric lymphoma were found and listed with details. The factors influencing the development of this secondary carcinoma, mainly those treatment related are discussed. The possible role of both radiotherapy and chemotherapy in shortening the latent period for the development of stump carcinoma is emphasized. © 1993 Wiley-Liss, Inc.  相似文献   
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The present study examined the effect of a short physical interactionwith condoms (opening packages, taking out the condoms and unrollingthem) on the attitude toward condoms and on intended condomuse. Using a pre-post experimental design, 101 adolescents wererandomly assigned to one experimental and four control groups.Subjects in the experimental group handled condoms for about10 min, answering questions about the difficulty of performingthe instructed tasks. In the first control group, subjects completeda filler questionnaire on HIV infection. Subjects in a secondcontrol group watched a peer from the experimental group andanswered similar questions about the difficulty of performingthe tasks. The attention of subjects in the third control groupwas focused away from the features of condoms that are associatedwith their use; subjects were instructed to look at the condomsand complete a filler task. Subjects in a last control groupwere to observe subjects from Control group 3 and to completethe same filler task. Results indicated that having a short,direct experience with condoms failed to influence the attitudetoward condom use and intended condom use. Post hoc examinationof the effects in the control groups, however, suggested thatinducing an affective focus in subjects resulted in positiveattitudinal changes and had a positive effect on the expectationto use condoms in the future.  相似文献   
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The authors describe a case of giant fusiform aneurysm of the basilar artery presenting with ischemic symptoms. Angiography and CT revealed vertebro-basilar fusiform aneurysmal dilatation. Fusiform vertebro-basilar ancurysm is associated with various complications particularly brain stem infarction. Similar lesions in the literature are reviewed and the relationship between this clinical entity and cerebral ischemia, particularly brainstem infarction are discussed.  相似文献   
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Using a reverberatory epilepiform discharge of hippocampal-parahippocampal circuits termed maximal dentate activation, this study investigated whether the local release of nitric oxide within these circuits functions as an antiepileptic agent. Two nitric oxide synthase inhibitors (l-nitro-arginine methyl ester and 7-nitro-indazole) and a guanylate cyclase inhibitor (methylene blue) were tested, and none had a significant effect on the time to onset or duration of maximal dentate activation. A membrane-permeable analogue of cyclic guanosine monophosphate (cGMP), 8-bromo-cGMP, caused an increase in the time to onset and a decrease in the duration of maximal dentate activation. The number of neurons expressing NADPH diaphorase activity (a marker for nitric oxide synthase) was also examined after repeated elicitation of maximal dentate activation. After 18 seizures there was a significant, but transient, decrease in the number of hilar/subgranular neurons that were NADPH diaphorase-positive. The decrease was only seen at 1 h after the last seizure. There was no induction of NADPH diaphorase activity. These results are not consistent with the hypothesis that, in hippocampal-parahippocampal circuits in vivo, nitric oxide is released in response to neuronal activity and then acts to terminate the neuronal activity.  相似文献   
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Fifteen parameters that play a role in the optimal transmission of therapeutic signals by inductively coupled implantable neurostimulator have been investigated. For this purpose, at first, a model of the system was constructed from which the system transfer function was obtained. Then, the relationship between the transfer gain and each parameter was evaluated using mathematical equations and a specifically built computer program. This study showed that the gain could be increased selecting small values for some parameters (the number of active coil windings, first radii of inner and outer paths of the core, heights of the core base and windings, position under the skin, internal resistances of the active and passive coils, tissue impedance between the contacts of electrode), and high values for the others (the number of passive coil windings, second radii of inner and outer paths of the core, frequency of the signal, relative magnetic permeability of the core). Critical saturation values were another considerable point. The nearest commercially available standard values should be preferred in practical applications.  相似文献   
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In this paper, an intelligent system is presented for interpretation of the Doppler signals of the heart valve diseases based on the pattern recognition. This paper especially deals with combination of the feature extraction and classification from measured Doppler signal waveforms at the heart valve using the Doppler Ultrasound. Because of this, a wavelet packet neural network model developed by us is used. The model consists of two layers: wavelet and multi-layer perceptron. The wavelet layer is used for adaptive feature extraction in the time-frequency domain and is composed of wavelet packet decomposition and wavelet packet entropy. The multi-layer perceptron used for classification is a feed-forward neural network. The performance of the developed system has been evaluated in 215 samples. The test results showed that this system was effective in detecting Doppler heart sounds. The correct classification rate was about 94% for abnormal and normal subjects.  相似文献   
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Twenty-three rifampicin-resistant methicillin-resistant Staphylococcus aureus (MRSA) isolated in three wards at a university hospital in Turkey between June, 2000, and February, 2001, were studied for their genetic relatedness using a combination of antibiogram, coagulase serotyping, coagulase gene polymorphism (coa-RFLP), and pulsed-field gel electrophoresis (PFGE). They all expressed high-level rifampicin resistance (MIC, >256 mg/L) and were resistant to gentamicin, kanamycin, amikacin, ciprofloxacin, tetracycline, and cadmium acetate and were susceptible to fusidic acid, vancomycin, trimethoprim, and mupirocin. They belonged to the same coagulase serotype (serotype IV) and had identical coa-RFLP patterns. In contrast, PFGE generated nine banding patterns designated type A, types A1-A5, B, C, and D. The most common PFGE pattern (type A) and its subtypes (types A1-A5) were seen in 20 (87%) of the 23 isolates in the three wards. The results demonstrated the acquisition of rifampicin resistance by different MRSA clones and the spread of one clone among patients in the three wards.  相似文献   
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