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Guidance and reference are provided for protocol designer. The classification of laser medical devices are introduced. The key points such as the selection of control group, evaluation indicators and method, criteria of inclusion and exclusion, and application of blinded, etc. are discussed, and the importance of management of defects in medical device is emphasized.
Subject(s)
Clinical Trial Protocols as Topic , Equipment and Supplies , Lasers , Research DesignABSTRACT
Objective:To analyze the volatile components in compound Shenqiyizhi powder. Methods: The technique of head-space solid phase micro extraction( HS-SPME) with gas chromatography-mass spectrometry ( GC-MS) was applied to study the vola-tile components in the compound powder. The compound essential oil was analyzed by steam distillation( SD) with GC-MS. Results:A total of 117 kinds of volatile components were detected, and among them, 70 kinds of chemical compositions were identified from the compound powder, accounting for 94. 46% of the total volatile components. The component with the highest content wasβ-himachalene followed by ylangene (15. 56%) and β-asarone (7. 36%). Totally 66 kinds of volatile components were detected from the compound essential oil by SD-GC-MS, and among them, 43 kinds were identified, accounting for 77. 41% of the total volatile components. The results indicated that the main volatile components were β-asarone (16. 73%), eugenol methyl ether (6. 74%) and ylangene (5. 81%). Conclusion:The main volatile components in Shenqiyizhi powders areβ-cedrene, ylangene,β-asarone,α-asarone and el-emicin etc. The research can provide scientific basis for the analysis of volatile components.
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Objective: To compare the volatile compounds extracted from Rhodiola renulata respectively by HS-SPME and SD. Methods:The volatile constituents from Rhodiola crenulata were extracted respectively by HS-SPME and SD, and then the contents and the names were confirmed by GC-MS. Results:Totally 39 compounds were identified from Rhodiola crenulata by HS-SPME while 16 ones were identified by SD. Among them, 4 common compounds were detected. Conclusion: There are some differences between the two methods. Compared with SD, HS-SPME is obviously better because more volatile constituents can be extracted from the herb, furthermore, HS-SPME has notable advantages of higher retrieval matching and sensitivity.