Hello! It seems that this question will have a better result if it goes to the database (Chongqing Weipu, Tsinghua HowNet, Wanfang, etc.). ), or go to a professional website like Lilac Garden. I found an article for you in Chongqing VIP, because the format problem may seem chaotic, so I suggest you use professional channels to obtain information. Research progress of oral sustained-release preparations in China Huang Shanghai pharmaceutical industry studies all oral sustained-release preparations. Controlled-release preparations can control the drug release rate within a predetermined time as needed, so that the human body can obtain a stable and effective therapeutic blood concentration, optimize the curative effect, and reduce the dosage, frequency and adverse drug reactions [9]. In the late 1950s, foreign countries began to develop oral controlled-release preparations, and in the 1970s, more and more drugs were approved for marketing by the medical community. At present, there are about 200 kinds of oral sustained and controlled release preparations listed abroad, and there are more than 400 kinds of goods with poor specifications. China began to develop oral sustained-release and controlled-release preparations in the late 1970s and early 1980s. In recent years, the number of units being developed and the types of drugs and preparations involved are increasing and expanding. The country pays more and more attention to the development of pharmaceutical preparations. During the "Seventh Five-Year Plan" period, the pharmaceutical discipline was first established as a national key scientific and technological project, including 9 kinds of oral sustained-release preparations, diltiazem (thioketone) intragastric sticky floating tablets, metoprolol (metoprolol) controlled-release tablets, zinc sulfate sustained-release preparations and isoniazid controlled-release tablets. There are more than 0 kinds of drugs listed in China (see table) And more than 30 drugs have been developed or are being developed (see Table 2), including nicotinamide alanyl sustained-release tablets, ibuprofen controlled-release preparations, phenylpropanolamine controlled-release suspensions, Shuchuanning controlled-release preparations and dipropylamine (diisopropylamine) sustained-release preparations. Oral sustained-release and controlled-release preparations usually delay the release rate of drugs in the gastrointestinal tract and the delivery rate of preparations C2~93 by means of preparations according to the diffusion, dissolution, permeation and ion exchange properties of drugs and the physiological characteristics of gastrointestinal tract. The types of oral sustained-release preparations studied in China include controlled-release pellets, sustained-release granules, sustained-release capsules, waxy matrix tablets, hydrophilic matrix tablets, mixed matrix tablets, microcapsule matrix tablets, film-coated matrix tablets, microporous film-coated tablets, film-coated tablets, osmotic pump tablets, controlled-release liquid preparations and gastric retention viscous floating tablets. 1. The research and development feature of sustained-release tablets and controlled-release tablets in China is 1. Medical colleges and research institutions pay attention to the combination of scientific research and production. With the in-depth development of China's economic system reform, medical colleges and research units actively promote the application of scientific research results, so that scientific research and production are more closely linked. Controlled-release tablets of ibuprofen, aminophylline, potassium chloride and ferrous thiosulfate developed by China Pharmaceutical University and Shanghai Institute of Pharmaceutical Industry have been mass-produced. Nifedipine sustained-release preparation, mexiletine microcapsule matrix tablets, piroxicam sustained-release tablets, ranitidine controlled-release tablets, and Wip hydrochloride information "Medical Information 1990 No.6 (total No.6 130)" are included in 1 ",and the produced oral cilia are released, and II4 sequences are knocked out, and classified for scientific research and production. Controlled tillage tablets 3 compound long-acting theophylline tablets skeleton tablets (1) film-coated skeleton tablets (2) sustained-release clenbuterol quick-release sustained-release series, the most layer or skeleton tablets are aimed at composite films. I. Isosorbide Sustained Release Tablets L, Parental Coagulation Cavity Matrix Tablets (Long-acting Xiaotong Tablets) L, F, Diltiazem Sulfate Controlled Release Tablets F, Potassium Chloride Sustained Release Tablets (1) Coated Controlled Release Tablets l j(2) Sustained Release Tablets Ferrous Sulfate Tablets L Forged Hole Coated Tablets Ibuprofen Controlled Release Tablets L Matrix Tablets} Isoniazid Dancing Release Tablets 1 Matrix Tablets L I Shanghai Xinyi Pharmaceutical Factory, China Pharmaceutical University -5 Liaoning Jinzhou Pharmaceutical Factory, Shijiazhuang No.1 Safety Factory, China Pharmaceutical University, Southwest Pharmaceutical Factory, Yantai Private Pharmaceutical Factory, Xijian Sipian Yaoguang Pharmaceutical Factory, Harbin No.4 Pharmaceutical Factory, Shanghai Yan 'an Factory, Southwest Sanguang Tianjin Safety Factory, Ji # Jiangyu Pharmaceutical Factory, Shanghai Pharmaceutical Industry Research Institute, Guangxi Guilin Pharmaceutical Factory, Weihai Xinhua Pharmaceutical Factory Shanghai Medical University School of Pharmacy Qingdao Huanghai Pharmaceutical Factory Shanghai Yan 'an Pharmaceutical Guangshangli Pharmaceutical Research Anhui Shanghai Huanghai Pharmaceutical Factory Shenyang No.4 Pharmaceutical Factory Shang Hui Pharmaceutical Industry Research Institute Shanghai Huanghaizha Pharmaceutical Factory Southwest China Pharmaceutical University Hunan Pharmaceutical Factory Hunan Anti-uplift Draft New-Hunan Drug Inspection Institute New China-US Tianlushi Kejian Pharmaceutical Co., Ltd. Plain matrix tablets and isoniazid microporous film coated tablets and other controlled-release preparations are expected to be listed in the near future. 2. The scientific research level of industrial system has been improved. In order to develop new dosage forms, many pharmaceutical companies have established pharmaceutical research institutes or laboratories. In the research and development of oral sustained and controlled release preparations, we combine the national conditions and the actual situation of our unit to develop vigorously. Through several years' efforts, the research level of enterprises has been greatly improved. It is reported in the literature that when preparing coated controlled-release pellets, the pellets are taken out of the pot in batches to obtain coated preparations with different release rates. Shenyang No.1 pharmacy