Aloe is a type of perennial herbs.It is a fleshy plant and belongs to lily family.In this paper,the author described its chemical compositions and medical role in health care.

The Nobel Prize in Chemistry 2004 was awarded to three scientists:Aaron Ciechanover,Avram Hershko and Irwin Rose.They succeeded in showing how proteins are destroyed in cells.The article introduce their discovery,especially the substances wanted in the course of the ubiquitin-mediated protein degradation and the mechanism.

Antioxidant is a kind of food additives that can prevent or postpone food oxidization and blet.Tea polyphenols,which cannot be synthesized up to the present,is an excellent antioxidant and a natural,multifunctional and high efficient free radical detergent.Tea polyphenols can be abstracted with supercritical CO₂fluid extraction,ion precipitation,resin adsorption stripping and organic solvent extraction methods.The contents of tea polyphenols in tea can be determined with ferrous tartrate colourimetry method.

The reform of teaching evaluation is an important part in the elementary education reform,and the self-evaluation of the student is a form in the variety evaluation.The author thinks that the teacher should design the mode of student self-evaluation to develop their abilities of meta-cognition and self-evaluation in order to promote the cultivation of the student's scientific quality and meta-cognition ability.