sas截取数据，真心求助大牛-经管之家官网！

Security No.	Participants
1	Servicer: 1st Financial BankUSA,Indenture Trustee: Bank of New York Mellon (The)
2	Indenture Trustee: Bank of NewYork Mellon (The),Servicer: 1st Financial Bank USA
3	Originator: 321 HendersonReceivables Origination LLC,Seller: 321 Henderson Receivables AcquisitionLLC,Master Servicer: J.G. Wentworth Management Co. Inc.,Underwriter: DeutscheBank Securities Inc.,Indenture Trustee: Wilmington Trust Company ,Bond Counsel:Sidley & Austin
4	Seller: 321 HendersonReceivables Acquisition LLC,Originator: 321 Henderson Receivables OriginationLLC,Owner Trustee: Deutsche Bank Trust Company Americas,Master Servicer: J.G.Wentworth Management Co. Inc.,Underwriter: Deutsche Bank Securities Inc.,IndentureTrustee: Wilmington Trust Company ,Bond Counsel: Sidley & Austin
5	Underwriter: Citigroup Global Markets Inc.,Bond Counsel: Foley & Lardner,Servicer: Access Group Inc,Underwriter: UBS Financial Services, Inc.,Trustee: Deutsche Bank Trust Company Americas,Underwriter: KeyBanc Capital Markets,Indenture Trustee: Deutsche Bank Trust Company Americas,Servicer: Kentucky Hgr Ed Std Ln Corp,Originator: Access Group Inc

有上万个这样的证券及相关参与方的数据，现在我想要新建一系列column，把诸如originator，underwriter，indenture trustee这样数据的分门别类地列出来。还有一点麻烦的是有时一个类别的参与方不止一个，例如No.5证券中underwriter有三个，还不是连着的。求助大牛应该怎么处理呢？
有几个想法：1.substr和find一起用，把“originator：”“,”的位置挑出来,截取其中的内容，但怎么样使找到的逗号是“originator：“之后第一个出现的逗号呢？而且这之后同一格中要再有一个underwriter该怎么办。。。
2.按逗号把Participants中的内容全部打断，放到不同column中（不知能否实现），然后再循环在每个row中分别依次找originator，underwriter，indenture trustee，这样每个待检索的cell中只会有一个逗号。
求大牛指点迷津，不胜感激~~~