AIM: The extent similarity algorithm was introduced, integrated clustering analysis to evaluate the quality of different sources of Flos lonicerae japonicae. METHODS: The fingerprint spectum of Flos lonicerae japonicae was established to calculate correlation coefficient, cosine of the included angle and extent similarity of thirty-five samples, and then clustering analysis was adopted. RESULTS: In combination of the extent similarity and the clustering analysis to evaluate the quality of Flos lonicerae japonicae, and the results showed that it accorded with reality. CONCLUSION: This method is accurate and reliable, and it is an apparent, credible and efficient method for quality evaluation of Chinese medicines.

Objective: To provide an easy and feasible algorithm of the similarity between chromatographic fingerprints of herbs. Methods: To calculate similarity by combining the chromatographic overlap rate with relative area or height of mutual peaks of chromatographic fingerprints. Results: The algorithm was applied to the chromatographic fingerprints of samples in two references and the result is consistent with the fact. Conclusion: The calculated similarity with the proposed method can be sensitive to indicate the difference between fingerprints of herbs and the provided algorithm is simple and easy to be used.

OBJECTIVE: To investigate the effect of temperature and time on the detection results of calcium and magnesium in urinary sample storage. METHODS: Urinary samples of 5 health volunteers were collected. The samples were stored in room temperature, 4 ℃ and-20 ℃ for different duration after sealed separately. A flame atomic absorption spectrometry was used to detect calcium and magnesium mass concentrations in the urinary samples. RESULTS: The variation rate of calcium and magnesium mass concentrations was <2.00% when urinary samples were stored at room temperature for 8 hours, the variation rate was <6.00% when samples were stored at 4 ℃ for 15 days, and it was <5.00% when samples were stored at-20 ℃ for 60 days. CONCLUSION: The temperature and time of urinary sample storage can affect the detection results of calcium and magnesium mass concentrations. Packing and storing samples at low temperature after collection as soon as possible is beneficial to ensure the accuracy of test results.