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We analyzed the management of regional lymph nodes in 110 patients with squamous cell carcinoma of the penis treated at the Netherlands Cancer Institute between 1956 and 1989 with curative intent. Of 66 patients who presented with unsuspected nodes 57 were placed on a surveillance program, while lymph node dissection was performed in 5 (with adjuvant external radiation therapy in 1) and 4 were treated with external radiation therapy only. The management of 40 patients with clinically suspected nodes included surveillance in 5, lymph node dissection in 27 (with adjuvant radiotherapy in 11), biopsy in 4 and external radiation therapy in 4. Postoperative radiotherapy had been given if more than 2 nodes were involved or when extracapsular growth was observed. Overall, 25 patients had a regional recurrence, 5 of whom could be cured subsequently. All regional recurrences developed within 2 years after primary treatment. Analysis showed 100% survival in histologically proved node negative patients (stage pN0). The success of lymph node dissection was related to the extent of the metastatic spread and to the number of involved nodes. Patients with 1 positive node and unilateral inguinal involvement showed a statistically significant survival advantage compared to patients with more extensive spread. Considering the indications for node dissection we found a clear relationship among T category, grade and the probability of lymph node invasion. Patients with stage T1 tumors and stage T2, grades 1 and 2 tumors presented significantly less often with lymphatic invasion than those with other categories of disease and were less likely to have a regional recurrence after treatment of the primary tumor only. In these categories we recommend surveillance of the regional lymph nodes in patients who present with unsuspected nodes. However, patients with stage T2 grade 3, stage T3 and operable stage T4 tumors should undergo an immediate inguinal node dissection because of the high probability of clinically occult lymph node invasion (in our material more than 50%). With respect to the extent of the node dissection, we found that the likelihood of spread to the contralateral and/or pelvic regions was related to the number of invaded nodes in the inguinal region. We recommend contralateral node dissection and unilateral pelvic node dissection when 2 or more positive nodes are found in the dissected groin specimen. Primary pelvic node dissection should be performed in patients who present initially with cytologically or biopsy proved positive inguinal nodes.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
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Synthesis is the automated construction of a system from its specification. In the classical temporal synthesis algorithms, it is always assumed the system is “constructed from scratch” rather than “composed” from reusable components. This, of course, rarely happens in real life. In real life, almost every non-trivial commercial system, either in hardware or in software system, relies heavily on using libraries of reusable components. Furthermore, other contexts, such as web-service orchestration, can be modeled as synthesis of a system from a library of components. In this work, we define and study the problem of LTL synthesis from libraries of reusable components. We define two notions of composition: data-flow composition, for which we prove the problem is undecidable, and control-flow composition, for which we prove the problem is 2EXPTIME-complete. As a side benefit, we derive an explicit characterization of the information needed by the synthesizer on the underlying components. This characterization can be used as a specification formalism between component providers and integrators.  相似文献   
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Pak R  Price MM 《Human factors》2008,50(4):614-628
OBJECTIVE: The present study examined Web-based information retrieval as a function of age for two information organization schemes: hierarchical organization and one organized around tags or keywords. BACKGROUND: Older adults' performance in information retrieval tasks has traditionally been lower compared with younger adults'. The current study examined the degree to which information organization moderated age-related performance differences on an information retrieval task. The theory of fluid and crystallized intelligence may provide insight into different kinds of information architectures that may reduce age-related differences in computer-based information retrieval performance. METHOD: Fifty younger (18-23 years of age) and 50 older (55-76 years of age) participants browsed a Web site for answers to specific questions. Half of the participants browsed the hierarchically organized system (taxonomy), which maintained a one-to-one relationship between menu link and page, whereas the other half browsed the tag-based interface, with a many-to-one relationship between menu and page. This difference was expected to interact with age-related differences in fluid and crystallized intelligence. RESULTS: Age-related differences in information retrieval performance persisted; however, a tag-based retrieval interface reduced age-related differences, as compared with a taxonomical interface. CONCLUSION: Cognitive aging theory can lead to interface interventions that reduce age-related differences in performance with technology. In an information retrieval paradigm, older adults may be able to leverage their increased crystallized intelligence to offset fluid intelligence declines in a computer-based information search task. APPLICATION: More research is necessary, but the results suggest that information retrieval interfaces organized around keywords may reduce age-related differences in performance.  相似文献   
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R Pak  N Fink  M Price  B Bass  L Sturre 《Ergonomics》2012,55(9):1059-1072
This study examined the use of deliberately anthropomorphic automation on younger and older adults' trust, dependence and performance on a diabetes decision-making task. Research with anthropomorphic interface agents has shown mixed effects in judgments of preferences but has rarely examined effects on performance. Meanwhile, research in automation has shown some forms of anthropomorphism (e.g. etiquette) have effects on trust and dependence on automation. Participants answered diabetes questions with no-aid, a non-anthropomorphic aid or an anthropomorphised aid. Trust and dependence in the aid was measured. A minimally anthropomorphic aide primarily affected younger adults' trust in the aid. Dependence, however, for both age groups was influenced by the anthropomorphic aid. Automation that deliberately embodies person-like characteristics can influence trust and dependence on reasonably reliable automation. However, further research is necessary to better understand the specific aspects of the aid that affect different age groups. Automation that embodies human-like characteristics may be useful in situations where there is under-utilisation of reasonably reliable aids by enhancing trust and dependence in that aid. Practitioner Summary: The design of decision-support aids on consumer devices (e.g. smartphones) may influence the level of trust that users place in that system and their amount of use. This study is the first step in articulating how the design of aids may influence user's trust and use of such systems.  相似文献   
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In an attempt to maintain the elimination of COVID-19 in New Zealand, all international arrivals are required to spend 14 days in government-managed quarantine and to return a negative test result before being released. We model the testing, isolation and transmission of COVID-19 within quarantine facilities to estimate the risk of community outbreaks being seeded at the border. We use a simple branching process model for COVID-19 transmission that includes a time-dependent probability of a false-negative test result. We show that the combination of 14-day quarantine with two tests is highly effective in preventing an infectious case entering the community, provided there is no transmission within quarantine facilities. Shorter quarantine periods, or reliance on testing only with no quarantine, substantially increases the risk of an infectious case being released. We calculate the fraction of cases detected in the second week of their two-week stay and show that this may be a useful indicator of the likelihood of transmission occurring within quarantine facilities. Frontline staff working at the border risk exposure to infected individuals and this has the potential to lead to a community outbreak. We use the model to test surveillance strategies and evaluate the likely size of the outbreak at the time it is first detected. We conclude with some recommendations for managing the risk of potential future outbreaks originating from the border.  相似文献   
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The preparation of a number of phenylacetyl and 3-phenylpropionyl derivatives of amino acids is described. Derivatives containing more than one aromatic group markedly inhibit ovine brain glutamine synthetase. All phenylacetyl and phenylpropionyl derivatives tested were resistant to hog kidney acylase I.  相似文献   
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