一个很大的excel文档，包含了人体内所有可测到的小分子代谢物两两之间的距离，下载自HMDB内部库。可辅助用于代谢物功能分析和代谢网络的绘制。-A lot of excel documents, including the distance can be measured in the human body all small molecule metabolites between pairwise, downloaded　HMDB internal library. Secondary metabolites can be used to draw the functional analysis and metabolic networks.