Objective: To identify Euryales Semen and its closely related species using the ITS2 barcode. Method:The total genomic DNAs were extracted from twenty samples of Euryales Semen and its closely related species. The ITS2 regions of the samples were amplified and bidirectional sequenced. Obtained sequences were submitted to the GenBank with Sequin 12.3. ITS2 sequences of 102 samples belonging to thirty species were downloaded from GenBank. The 122 ITS2 sequences were aligned and the genetic distances were analyzed with MEGA 5.1. Identification analyses were performed using BLAST1 and nearest distance methods, and were presented intuitively by constructing neighbor-joining (NJ) tree. Result: The length of ITS2 region of Euryales Semen was 214 bp, which was only one haplotype. There was significant divergence of the ITS2 regions among the samples. The NJ tree showed that Euryales Semen could be obviously differed from its closely related species, which had good 408 monophyly. Conclusion: ITS2 regions as a DNA barcode can stably and accurately distinguish Euryales Semen from its closely related species and also provide a new technique to ensure clinical safety in utilization of tradi-tional Chinese medicines. The new exploration could broaden the application of DNA barcoding technology in identification of Traditional Chinese Medicine.

Carrying out extracurricular research activities for undergraduates in medical colleges and universities can stimulate the creativity of undergraduates. This article analyzes the significance, existing problems, and solutions of extracurricular research activities for clinical medical undergraduates. At the same time, corresponding countermeasures are proposed, including standardized training of research operations for students, time coordination of extracurricular research activities for undergraduates, and reasonable arrangement of teaching tasks for tutors. Medical students need to handle the relationship among study, community, part-time jobs, extracurricular activities, and extracurricular research, and make a rational time arrangement for participation. Young teachers in medical colleges and universities should arrange their time reasonably to undertake the corresponding tasks of research and teaching.