Medicine information retrieval has grown significantly and is based on the structural similarity of medicine molecules. The chemical structural formula (CSF) is a primary search target as a unique identifier for each compound in the research field of medical information. This paper introduces a graph-based CSF retrieval system, PharmKi, which accepts the photos taken from smartphones and the sketches drawn on the tablet PCs as inputs. To establish a compact yet efficient hypergraph representation for molecules, we propose a graph-isomorphism-based algorithm for evaluating the spatial similarity between graphical CSFs. An indexing strategy based on the graph TF-IDF technology is also introduced to achieve a high efficiency for large-scale molecule retrieval. The results of comparative study demonstrate that the proposed method outperforms the existing methods on accuracy, and performs well on efficiency.

中文翻译：

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基于图相似度的药物分子检索系统

基于药物分子的结构相似性，医学信息检索已显着增长。化学结构式（CSF）是医学信息研究领域中每种化合物的唯一标识的主要搜索目标。本文介绍了一种基于图形的CSF检索系统PharmKi，该系统接受从智能手机拍摄的照片和在平板电脑上绘制的草图作为输入。为了建立分子的紧凑而有效的超图表示，我们提出了一种基于图同构的算法，用于评估图形化CSF之间的空间相似性。还引入了基于图TF-IDF技术的索引策略，以实现大规模分子检索的高效率。