Trade associations shall be established in accordance with the current state classificatory standards of trades or of products , or in accordance with the forms of operations or links in the operation chain or with service functions .
行业协会按照国家现行行业或者产品分类标准设立,也可以按照经营方式、经营环节及服务功能设立。
Taking aconitase as an example in this paper , the mechanism of symmetric substrate molecule selected by enzyme was discussed thoroughly , and the classificatory system of enzyme specificity was analyzed and readjusted .