INVITED REVIEW POLYMERIC DELIVERY SYSTEMS FOR CONTROLLED DRUG RELEASE

The use of polymers to provide controlled long-term delivery of drugs and other chemicals is a rapidly emerging field. This review focuses primarily on the applications of these polymeric systems, and their release mechanisms. Examples of applications include clinical, pharmaceutical, biological, agricultural, environmental, and household uses. Release mechanisms considered are diffusive (reservoirs, matrices), chemical (biocrosion, pendent chain), swelling, and magnetic control of drug release from polymers. Advantages and disadvantages of controlled-release technology, and approaches for developing and testing effective polymeric delivery systems arediscussed.     

丁苯橡胶国内外近况及展望

本文介绍了丁苯橡胶近十年来国内外发展概况和前景。国外的情况是:80年代初SBR产、耗量降至历史最低水平;中期缓慢回升,后期稳定发展;今后将以提高质量和功能为主,稳定地发展产量。我国SBR在80年代获得了很大发展,生产能力已达到20.4万吨/年,今后将随着整个国民经济的发展而发展。