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231.
232.
S. Biswas A. Bhelwa A. Itoop S. Biswal N. Nath 《Indian journal of clinical biochemistry : IJCB》1994,9(1):9-12
Membrane hydrophobicity and slalidase activity of normal Poly morphonuclear Leucocyte were significantly enhanced when incubated with DSF. As a consequence, internalisation ofE. coli andS. aureus (opsonised or unopsonised) were greatly dimnished, internalisation ofE. coli being higher in either category. Although, increase in hydrophobicity of the membrane correlated well with the time of decrease of particle internalisation (both at 30 min.), enhancement of sialidase activity did not coincide with the said alterations. 相似文献
233.
This article addresses file maintenance of subject headings in the National Library of Medicine's MEDLINE, a bibliographic retrieval file which is indexed using Medical Subject Headings (MeSH), NLM's subject authority. The emphasis is class maintenance in which sets of records in MEDLINE are changed by maintenance actions which reflect yearly changes in MeSH. Specific types of maintenance action are described with examples to highlight problem areas. Class maintenance failures, checking class maintenance, and informing end-users of MeSH changes resulting in class maintenance are discussed. Technical constraints and feasibility are not analyzed in detail; rather, the approach is geared toward requirements and impact of maintenance from the standpoint of vocabulary specialists and end-users. The article concludes with a brief statement on defining file maintenance policy. 相似文献
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C.S. Badue R. Baeza-Yates B. Ribeiro-Neto A. Ziviani N. Ziviani 《Information processing & management》2007
The performance of parallel query processing in a cluster of index servers is crucial for modern web search systems. In such a scenario, the response time basically depends on the execution time of the slowest server to generate a partial ranked answer. Previous approaches investigate performance issues in this context using simulation, analytical modeling, experimentation, or a combination of them. Nevertheless, these approaches simply assume balanced execution times among homogeneous servers (by uniformly distributing the document collection among them, for instance)—a scenario that we did not observe in our experimentation. On the contrary, we found that even with a balanced distribution of the document collection among index servers, correlations between the frequency of a term in the query log and the size of its corresponding inverted list lead to imbalances in query execution times at these same servers, because these correlations affect disk caching behavior. Further, the relative sizes of the main memory at each server (with regard to disk space usage) and the number of servers participating in the parallel query processing also affect imbalance of local query execution times. These are relevant findings that have not been reported before and that, we understand, are of interest to the research community. 相似文献
236.
供应链上下游企业合作研发模式选择--宝钢-大众激光拼焊项目案例分析 总被引:8,自引:0,他引:8
企业供应链的发展促使企业合作研发寻求新的模式。分析了上下游大型企业进行合作研发的诱因及其模式选择问题,结合宝钢一上海大众激光拼焊案例,重点讨论了建立股权制合作研发对上下游企业的影响和供应链创新的意义。 相似文献
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This study examined whether high- and low-IQ poor readers differed in patterns of reading performance. Ten-year-old poor readers with IQ scores of 110 and higher showed difficulty in taking a phonological approach to reading, failing to show an advantage in reading high-frequency regular versus irregular words and showing impaired nonword reading accuracy for their reading age. However, poor readers with IQ scores of 90 and below showed a more phonological approach to reading, with better reading of regular than irregular words of both high and low frequency, and with nonword reading skills slower than, but as accurate as, those of reading-age controls. We concluded that the high-IQ poor readers experienced difficulty in taking a phonological approach to reading, whereas the low-IQ poor readers had much less marked phonological problems, supporting Stanovich's phonological-core variable-difference model. 相似文献
240.
A meta-analytic investigation of therapy modality outcomes for sexually abused children and adolescents: an exploratory study 总被引:1,自引:0,他引:1
OBJECTIVE: The purpose of the current study was to investigate the independent effects of different treatment elements on a number of secondary problems related to childhood and adolescent sexual abuse, as well as investigate a number of different moderators of treatment effectiveness. METHOD: Twenty-eight studies that provided treatment outcome results for children and adolescents who had been sexually abused were included in the meta-analysis. Different aspects of psychological treatment, such as specific treatment modalities (individual, cognitive-behavioral, etc.) or secondary problems (behavior problems, psychological distress, etc.) were investigated. RESULTS: The overall mean weighted effect size for the meta-analysis was d=.72 (SE=.02). The results indicate that psychological treatment after childhood or adolescent sexual abuse tended to result in better outcomes than no treatment. There was significant heterogeneity in the effectiveness of the various psychological treatment elements. Play therapy seemed to be the most effective treatment for social functioning, whereas cognitive-behavioral, abuse-specific, and supportive therapy in either group or individual formats was most effective for behavior problems. Cognitive-behavioral, family, and individual therapy seemed to be the most effective for psychological distress, and abuse-specific, cognitive-behavioral, and group therapy appeared to be the most effective for low self-concept. CONCLUSIONS: The choice of therapy modality should depend on the child's main presenting secondary problem. Further research should be conducted investigating other possible moderators and secondary problem outcomes. 相似文献