To prepare a solid dispersion of cisapride with hydroxypropylmethyl cellulose(HPMC E5 LV) as carrier for the purpose of accelerating the in vitro drug release by means ofimproving the solubility of the model drug. Met...To prepare a solid dispersion of cisapride with hydroxypropylmethyl cellulose(HPMC E5 LV) as carrier for the purpose of accelerating the in vitro drug release by means ofimproving the solubility of the model drug. Methods Alcohol and simulated gastric fluid (SGF) wereused to dissolve cisapride and HPMC in order to make the model drug dispersed homogeneously in thecarrier. The HPMC-cisapride solid dispersion was then obtained by conventional solvent evaporationmethod. Powder X-ray diffraction (XRD) was used to measure the diffraction peaks of pure carrier,pure cisapride, physical mixture of HPMC with cisapride (4:1), and HPMC-cisapride solid dispersion(4:1) to confirm the crystal existence. The solubility of pure drug and HPMC-cisapride soliddispersion was measured with water, SGF and simulated intestinal fluid (SIF) . The in vitro drugreleases of the sustained release tablet prepared with pure cisapride or HPMC-cisapride soliddispersion were investigated with water and SGF as media, respectively. Results No diffraction peakswere found by X-ray diffraction in the HPMC-cisapride solid dispersion (4:1), indicating that thedrug existed in an amorphous form at that drug-carrier ratio. Compared with the pure drug, thesolubilities of HPMC-cisapride solid dispersion are increased by 239.4% in SGF, 132.6% in water, and117.9% in SIF. According to the in vitro drug release, the sustained release tablet prepared withHPMC-cisapride solid dispersion had a faster drug release than did that prepared with pure drug. Thein vitro drug release profiles were found to comply with Higuchi's rule. Conclusion The in vitrodrug release of the sustained release tablet made by HPMC-cisapride solid dispersion is improvedowing to the increased drug solubility.展开更多
The basic characteristics of the soft rock roadway under the dynamic pressure are analyzed. At the same time, the three fundamental approaches for controlling the surrounding rock are proposed, which are improving the...The basic characteristics of the soft rock roadway under the dynamic pressure are analyzed. At the same time, the three fundamental approaches for controlling the surrounding rock are proposed, which are improving the surrounding rock strength, lowering the rock mass stress and selecting the reasonable supporting technology. The research results are elucidated, including the distribution of the surrounding rock plastic zone, the movement and damage of the surrounding rock under the dynamic pressure, controlling the floor heave through reinforcing the roadway walls and corners, the new route to develop the roadway metal supporting technique, the key theory and technique for the bolt supporting in the coal roadway, the performance and prospect of the ZKD high water content quick setting material, and so on. Finally, some personally views are put forward about the roadway metal supporting, bolt supporting, new material and the stress relief under the high stress condition.展开更多
Objective Study of bupropion hydrochloride gel matrix sustained release tablet and the preparation method, test the skeleton material of hydroxypropyl methyl cellulose influencing drug release for evaluation, explore ...Objective Study of bupropion hydrochloride gel matrix sustained release tablet and the preparation method, test the skeleton material of hydroxypropyl methyl cellulose influencing drug release for evaluation, explore the preparation of sustained release tablets of optimization method. Method With hydroxypropyl methyl cellulose as skeleton material, according to the different prescription preparation of bupmpion hydrochloride sustained release tablets. Different HPMC viscosity, Consumption, particle size, compression pressure and slurry rotational speed and other factors, analysis the influence on drug release rate.Through the release of test evaluation of sustained release effect, and the preliminary study on the drug release characteristic. With hydroxypropyl methyl cellulose （ HPMC ） as skeleton material, with citric acid citrate as a porogenic agent, direct powder tabletting method of bupropion hydrochloride sustained release tablets; by using single factor and orthogonal experiment method to investigate HPMC different viscosity, different Consumption, different particle size, different compression pressure, different pulp rotational speed and other factors on the release of delivery rate. Result Select HPMC-K100M for bupropion hydrochloride sustained release tablets of the skeleton materials; reinforcing materials of high viscosity HPMC K100M and main drug quality ratio of 1： 1; HPMC particle diameter of 125p m, make use of these conditions to preparation of bupropion hydrochloride sustained release tablets for optimal prescription conditions. Conclusion bupropion hydroehloride sustained release tablets on the drug release rate is mainly affected by HPMC viscosity and dosage effect. Along with the tablet of HPMC viscosity increased, the drug is released slowly. HPMC viscosity, dosage on the drug release rate has significant influence.展开更多
Objective:The cross-linked production,which was prepared by HA and cross-linking agent STMP,EDC,GP through cross-linking reaction,might be used in drug delivery system(DDS).To ensure the security of clinical applicati...Objective:The cross-linked production,which was prepared by HA and cross-linking agent STMP,EDC,GP through cross-linking reaction,might be used in drug delivery system(DDS).To ensure the security of clinical application,the excellent properties such as none cell toxicity,nonirritant,none general toxicity,none immunological rejection are necessary.Methods:In accordance with the request of GB/T 16886.1 on security evaluation of medical biomaterials,cell toxicity test,hemolysis test,intracutaneous stimulation test,acute toxicity test,and hypersensitive test were required.Results:Cell toxicity of HA-STMP,HA-EDC,HA-GP were all less than 1.All hypersensitive tests were eligible.But HA-EDC,HA-GP produced different degrees of slight thrill,slight toxicity,hemolysis rate,which were larger than the standard value.Conclusion:HA-STMP possesses favourable biocompatibility,which is a kind of ideal biomaterials and drug carriers.展开更多
Microalgae could be a new sustainable energy source substituted for petroleum. They can produce high value biodiesel, bioethanol, bio-hydrogen, biogas, and that they are able to use waste water and nutrients, allowing...Microalgae could be a new sustainable energy source substituted for petroleum. They can produce high value biodiesel, bioethanol, bio-hydrogen, biogas, and that they are able to use waste water and nutrients, allowing for integration of such processes with waste treatment. Open ponds in hectares of area, could remove excess CO2 in atmosphere with photosynthesis. Large scale microalgal production in fields which are not suitable for agriculture could be a solution for CO： capturing from the atmosphere. Sea water could be used for the culture medium not to consume the fresh water. However microalgae reduce the atmospheric CO： while producing the organic material, using the biomass for either fuel production or food, feed, fertilizer, come out with CO2 release to the atmosphere, when burned by the engine, body and/or bacterial activities. So, microalgal growth can＇t reduce the CO2 however makes an important contribution to keep the atmospheric CO2 level stable. Long term solution for removing the CO2, could be possible with making durable biomaterials with microalgal biomass and capture the atmospheric CO2 by fixing into the materials and interrupt the carbon cycle for a long while.展开更多
文摘To prepare a solid dispersion of cisapride with hydroxypropylmethyl cellulose(HPMC E5 LV) as carrier for the purpose of accelerating the in vitro drug release by means ofimproving the solubility of the model drug. Methods Alcohol and simulated gastric fluid (SGF) wereused to dissolve cisapride and HPMC in order to make the model drug dispersed homogeneously in thecarrier. The HPMC-cisapride solid dispersion was then obtained by conventional solvent evaporationmethod. Powder X-ray diffraction (XRD) was used to measure the diffraction peaks of pure carrier,pure cisapride, physical mixture of HPMC with cisapride (4:1), and HPMC-cisapride solid dispersion(4:1) to confirm the crystal existence. The solubility of pure drug and HPMC-cisapride soliddispersion was measured with water, SGF and simulated intestinal fluid (SIF) . The in vitro drugreleases of the sustained release tablet prepared with pure cisapride or HPMC-cisapride soliddispersion were investigated with water and SGF as media, respectively. Results No diffraction peakswere found by X-ray diffraction in the HPMC-cisapride solid dispersion (4:1), indicating that thedrug existed in an amorphous form at that drug-carrier ratio. Compared with the pure drug, thesolubilities of HPMC-cisapride solid dispersion are increased by 239.4% in SGF, 132.6% in water, and117.9% in SIF. According to the in vitro drug release, the sustained release tablet prepared withHPMC-cisapride solid dispersion had a faster drug release than did that prepared with pure drug. Thein vitro drug release profiles were found to comply with Higuchi's rule. Conclusion The in vitrodrug release of the sustained release tablet made by HPMC-cisapride solid dispersion is improvedowing to the increased drug solubility.
文摘The basic characteristics of the soft rock roadway under the dynamic pressure are analyzed. At the same time, the three fundamental approaches for controlling the surrounding rock are proposed, which are improving the surrounding rock strength, lowering the rock mass stress and selecting the reasonable supporting technology. The research results are elucidated, including the distribution of the surrounding rock plastic zone, the movement and damage of the surrounding rock under the dynamic pressure, controlling the floor heave through reinforcing the roadway walls and corners, the new route to develop the roadway metal supporting technique, the key theory and technique for the bolt supporting in the coal roadway, the performance and prospect of the ZKD high water content quick setting material, and so on. Finally, some personally views are put forward about the roadway metal supporting, bolt supporting, new material and the stress relief under the high stress condition.
文摘Objective Study of bupropion hydrochloride gel matrix sustained release tablet and the preparation method, test the skeleton material of hydroxypropyl methyl cellulose influencing drug release for evaluation, explore the preparation of sustained release tablets of optimization method. Method With hydroxypropyl methyl cellulose as skeleton material, according to the different prescription preparation of bupmpion hydrochloride sustained release tablets. Different HPMC viscosity, Consumption, particle size, compression pressure and slurry rotational speed and other factors, analysis the influence on drug release rate.Through the release of test evaluation of sustained release effect, and the preliminary study on the drug release characteristic. With hydroxypropyl methyl cellulose （ HPMC ） as skeleton material, with citric acid citrate as a porogenic agent, direct powder tabletting method of bupropion hydrochloride sustained release tablets; by using single factor and orthogonal experiment method to investigate HPMC different viscosity, different Consumption, different particle size, different compression pressure, different pulp rotational speed and other factors on the release of delivery rate. Result Select HPMC-K100M for bupropion hydrochloride sustained release tablets of the skeleton materials; reinforcing materials of high viscosity HPMC K100M and main drug quality ratio of 1： 1; HPMC particle diameter of 125p m, make use of these conditions to preparation of bupropion hydrochloride sustained release tablets for optimal prescription conditions. Conclusion bupropion hydroehloride sustained release tablets on the drug release rate is mainly affected by HPMC viscosity and dosage effect. Along with the tablet of HPMC viscosity increased, the drug is released slowly. HPMC viscosity, dosage on the drug release rate has significant influence.
文摘Objective:The cross-linked production,which was prepared by HA and cross-linking agent STMP,EDC,GP through cross-linking reaction,might be used in drug delivery system(DDS).To ensure the security of clinical application,the excellent properties such as none cell toxicity,nonirritant,none general toxicity,none immunological rejection are necessary.Methods:In accordance with the request of GB/T 16886.1 on security evaluation of medical biomaterials,cell toxicity test,hemolysis test,intracutaneous stimulation test,acute toxicity test,and hypersensitive test were required.Results:Cell toxicity of HA-STMP,HA-EDC,HA-GP were all less than 1.All hypersensitive tests were eligible.But HA-EDC,HA-GP produced different degrees of slight thrill,slight toxicity,hemolysis rate,which were larger than the standard value.Conclusion:HA-STMP possesses favourable biocompatibility,which is a kind of ideal biomaterials and drug carriers.
文摘Microalgae could be a new sustainable energy source substituted for petroleum. They can produce high value biodiesel, bioethanol, bio-hydrogen, biogas, and that they are able to use waste water and nutrients, allowing for integration of such processes with waste treatment. Open ponds in hectares of area, could remove excess CO2 in atmosphere with photosynthesis. Large scale microalgal production in fields which are not suitable for agriculture could be a solution for CO： capturing from the atmosphere. Sea water could be used for the culture medium not to consume the fresh water. However microalgae reduce the atmospheric CO： while producing the organic material, using the biomass for either fuel production or food, feed, fertilizer, come out with CO2 release to the atmosphere, when burned by the engine, body and/or bacterial activities. So, microalgal growth can＇t reduce the CO2 however makes an important contribution to keep the atmospheric CO2 level stable. Long term solution for removing the CO2, could be possible with making durable biomaterials with microalgal biomass and capture the atmospheric CO2 by fixing into the materials and interrupt the carbon cycle for a long while.
