Astragalus membranaceus possesses the function of enhancing immunity, protecting the liver, diuretic, anti-aging, anti-stress, anti-hypertensive, and more extensive antibacterial effects. Polysaccharides, one kind of the major active ingredients of A. membranaceus, are considered to be responsible for their versatile use. Now, a systematic summary of research progress and prospects of polysaccharides from A. membranaceus polysaccharides (AMPs) is necessary to facilitate their further study and application. In this review, the optimal extraction methods, structural features, biological activities, and applications of AMPs were emphasized. The structure-activity relationships are also analyzed and elucidated. Solvent, ultrasonic, microwave, enzyme-assisted, ultra-high pressure, and combined methods have been used to extract AMPs. Among them, solvent extraction is the most commonly used method because it is simple and easy to operate, but the efficiency needs to be improved further. The ultra-high pressure method is the most efficient but has a low economic return. AMPs exhibited various bioactivities, including immunomodulation, antitumor, and antidiabete. The structure-activity relationships revealed that different structure configurations, chain conformations, and physical properties would have different bioactivities. However, the new method for purification of certain polysaccharides, detailed structure-activity relationships (SAR), mechanisms of bioactivities, and quality control of AMPs need to be extensively investigated.

Objective To study the correlation with ketamine and its metabolite norketamine concentration in plasma and saliva in acute toxic rabbits.Methods Experimental rabbits were given intragastric(i.g.group,n=6)and intravenous(i.v.group,n=6)administration of ketamine respectively,and control tabbits(n=6)were given a same volume of physiologic saline.The plasma and saliva were collected before and after ketamine administration.Ketamine and norketamine in plasma and saliva were determined using GC/MS and GC.The correlation with ketamine(norketamine)concentration in plasma and saliva were artalyzed by a double variable Pearson correlation analysis.Results The correlation coefficients(r)of ketamine (norketamine)concentrations in plasma and saliva were from 0.80 to 0.95 in ketamine i.g.group and i. v.group.Conclusion There is a good relativity between the concentration of ketamine(norketamine)in plasma and in saliva.The ketamine(norketamine)concentration in saliva can be used to estimate the plasma concentration in the forensic identification of ketamine abuse.