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Gray scale B-scans in renal sinus lipomatosis show a variety of features which must be differentiated from clinically significant pathological processes. Normal kidneys show dense homogeneous central echoes. In renal sinus lipomatosis, however, the central echoes are divided and become more sparse (Type I), interspersed with small relatively echo-free areas (Type II), or outline a single relatively echo-free area resembling a mass (Type III). In contrast to similar features in hydronephrosis or multiple cysts, the relatively echo-free areas in lipomatosis are ill-defined and do present several weak internal echoes.  相似文献   
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Cooperative defensive systems communicate and cooperate in their response to worm attacks, but determine the presence of a worm attack solely on local information. Distributed worm detection and immunization systems track suspicious behavior at multiple cooperating nodes to determine whether a worm attack is in progress. Earlier work has shown that cooperative systems can respond quickly to day-zero worms, while distributed detection systems allow detectors to be more conservative (i.e., paranoid) about potential attacks because they manage false alarms efficiently. In this paper we present our investigation into the complex tradeoffs in such systems between communication costs, computation overhead, accuracy of the local tests, estimation of viral virulence, and the fraction of the network infected before the attack crests. We evaluate the effectiveness of different system configurations in various simulations. Our experiments show that distributed algorithms are better able to balance effectiveness against worms and viruses with reduced cost in computation and communication when faced with false alarms. Furthermore, cooperative, distributed systems seem more robust against malicious participants in the immunization system than earlier cooperative but non-distributed approaches.  相似文献   
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Conducted 3 experiments, with a total of 272 Ss, to test an associative learning model. Fictitious consumer-product brands were used as stimuli and brand evaluations as responses. In each experiment, Ss received messages concerning up to 54 brands drawn from up to 12 product categories. Exp I demonstrated associative interference—messages advocating diverse evaluations of similar products led to rapid decay of persuasion. Exp II demonstrated reduction of associative interference—messages advocating similar evaluative responses to similar products facilitated associative learning and attenuated decay of persuasion. Exp III demonstrated the correlation between learning of brand-evaluation associations and persuasion. Results suggest that associative learning theory can provide a useful tool for analyzing the persisting impacts of persuasive messages in message-dense environments. (14 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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OBJECTIVE: The authors examined the efficacy of intramuscular flunitrazepam compared with intramuscular haloperidol for the immediate control of agitated or aggressive behavior in acutely psychotic patients. METHOD: Twenty-eight actively psychotic inpatients, aged 20-60 years, who were under treatment with neuroleptic agents were selected for the study. Each was randomly assigned on a double-blind basis to receive either 5 mg i.m. of haloperidol (N=13) or 1 mg i.m. of flunitrazepam (N=15) during an aggressive event. Verbal and physical aggression was measured over time with the Overt Aggression Scale. Patients were also rated with the Brief Psychiatric Rating Scale and the Clinical Global Impression scale. RESULTS: Both flunitrazepam and haloperidol exhibited acute antiaggressive activity. This beneficial effect, as assessed by the Overt Aggression Scale, was obtained within 30 minutes. CONCLUSIONS: Intramuscular flunitrazepam may serve as a convenient, rapid, safe, and effective adjunct to neuroleptics in reducing aggressive behavior in emergency psychiatric settings.  相似文献   
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