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71.
Historical text archives constitute a rich and diverse source of information, which is becoming increasingly readily accessible, due to large-scale digitisation efforts. However, it can be difficult for researchers to explore and search such large volumes of data in an efficient manner. Text mining (TM) methods can help, through their ability to recognise various types of semantic information automatically, e.g., instances of concepts (places, medical conditions, drugs, etc.), synonyms/variant forms of concepts, and relationships holding between concepts (which drugs are used to treat which medical conditions, etc.). TM analysis allows search systems to incorporate functionality such as automatic suggestions of synonyms of user-entered query terms, exploration of different concepts mentioned within search results or isolation of documents in which concepts are related in specific ways. However, applying TM methods to historical text can be challenging, according to differences and evolutions in vocabulary, terminology, language structure and style, compared to more modern text. In this article, we present our efforts to overcome the various challenges faced in the semantic analysis of published historical medical text dating back to the mid 19th century. Firstly, we used evidence from diverse historical medical documents from different periods to develop new resources that provide accounts of the multiple, evolving ways in which concepts, their variants and relationships amongst them may be expressed. These resources were employed to support the development of a modular processing pipeline of TM tools for the robust detection of semantic information in historical medical documents with varying characteristics. We applied the pipeline to two large-scale medical document archives covering wide temporal ranges as the basis for the development of a publicly accessible semantically-oriented search system. The novel resources are available for research purposes, while the processing pipeline and its modules may be used and configured within the Argo TM platform.  相似文献   
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Phenols were detoxified in the Onycophoran Peripatoides novaezealandiae by conjugation with sulphuric acid and phosphoric acid, but no evidence for a glycoside detoxication could be found. [(14)C]Benzoic acid was metabolized in 24h to N(2)-benzoyl-l-histidine, which was identified by electrophoresis, chromatography and dilution analysis. Similar conjugates were formed with p-aminobenzoic acid and p-nitrobenzoic acid. In longer-duration experiments further unidentified metabolites were formed, two of which appeared to result from the further metabolism of the histidine conjugate.  相似文献   
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During a six-month study at Lake George, N.Y., zooplankton contributed an average of 19.4% of the phosphate required for algal photosynthesis. Values ranged from 44.1% prior to the unimodal phytoplankton pulse to 4.6% during the phytoplankton bloom. Copepods accounted for a large percentage (21–68%) of the SRP recycled during the growing season examined, whereas, the cladocera provided only a small percentage of remineralization (6.9%).Contribution No. 315 from the Eastern Deciduous Forest Biome, U. .-IBP, Research supported by the Eastern Diciduous Forest Biome U.S.-IBP, funded by the National Science Foundation under interagency agreement AG-199. DEB 76-00761 with the U.S. Department of Energy — Oak Ridge National Laboratory.  相似文献   
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Studies on 300 worm-free chickens infected with Ascaridia galli indicated that the histotropic phase is a normal part of the life cycle and that it involves both second- and third-stage larvae. The duration of the histotropic phase was dose-dependent. At low dose rates (50 eggs) it occurred from days 3 to 16 and was terminated abruptly by the third ecdysis. At high dose rates (2000 eggs) it was prolonged until at least day 54, because third-stage larvae became arrested in their development and the third ecdysis was delayed. Arrested development of Ascaridia galli was significantly suppressed following treatment of birds with cyclophosphamide, but expulsion of worms was not prevented. This result suggests the involvement of host antibodies in the induction of the arrested state.  相似文献   
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