This paper describes an adjustable method for body composition analysis of awake mice based on time domain nuclear magnetic resonance (TD-NMR) technology. A T 1 -weighted CPMG pulse sequence was introduced to acquire the NMR signals that contain both longitudinal ( T 1 ) and transversal ( T 2 ) relaxation information of mice. It took less than 90 s to dramatically lighten the burden on animals. A model training according to a well-designed factorial experiment was conducted by measuring a series of artificial samples, and the relations between NMR signals and body components (lean, fat and free fluid) were established. This NMR model gave a good fitting ( R 2 > 0.99) between real values and predictive values and measuring stability were also demonstrated. A calibration method was highlighted to figure out how to keep NMR model effective on another NMR scanner or avoid the error from fluctuation of machine without a time-consuming re-modeling process.

中文翻译：

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一种用于快速定量分析清醒小鼠身体成分的可调 TD-NMR 方法

本文介绍了一种基于时域核磁共振 (TD-NMR) 技术的清醒小鼠身体成分分析的可调方法。引入AT 1 加权CPMG脉冲序列，获取包含小鼠纵向（T 1 ）和横向（ T 2 ）弛豫信息的NMR信号。只用了不到 90 秒的时间就大大减轻了动物的负担。通过测量一系列人工样本，根据精心设计的析因实验进行模型训练，并建立了核磁共振信号与身体成分（瘦肉、脂肪和游离液体）之间的关系。该 NMR 模型在实际值和预测值之间给出了良好的拟合 (R 2 > 0.99)，并且还证明了测量稳定性。