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Lappaconitine solid dispersion monolithic osmotic tablet and lappaconitine push-pull osmotic pump: preparation and comparison of their release performance in vitro 被引量:4
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作者 吴先闯 王姣姣 +4 位作者 郝海军 宋晓勇 张永州 刘瑜新 张红芹 《Journal of Chinese Pharmaceutical Sciences》 CAS CSCD 2017年第6期413-422,共10页
Lappaconitine is a water-insoluble drug, which was used as model drug in this study. Currently, two osmotically controlled delivery systems that are widely used for water-insoluble drug are monolithic osmotic tablet ... Lappaconitine is a water-insoluble drug, which was used as model drug in this study. Currently, two osmotically controlled delivery systems that are widely used for water-insoluble drug are monolithic osmotic tablet (MOT) and push-pull osmotic pump (PPOP). In the present study, lappaconitine solid dispersion monolithic osmotic tablet (lappaconitine-SD-MOT) and lappaconitine-PPOP were developed. The prepared lappaconitine-PPOP was able to delivery drug at the rate of approximate zero-order (r = 0.9931), and the cumulative release was above 95.0%. The lappaconitine-SD-MOT showed a comparatively poor linearity when the data were plotted according to the zero-order equation (r = 0.9798), and the cumulative release was 84.69%. Lappaconitine-PPOP exhibited better controlled drug release (higher regression value) compared with lappaconitine-SD-MOT. The similarity index (f2) between lappaconitine-PPOP and lappaconitine-SD-MOT was 49.1 (〈50). A clear difference of drug release characteristics between the lappaconitine-SD-MOT and lappaconitine-PPOP was revealed. It indicated that the drug release performance of lappaconitine-PPOP could gain favorable zero-order kinetics and higher cumulative release compared with lappaconitine-SD-MOT. Therefore, these results suggested that PPOP was still a very effective device for the delivery of poorly water-soluble drug with zero-order pattern. 展开更多
关键词 LAPPACONITINE Solid dispersion Monolithic osmotic tablet Push-pull osmotic pumps
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Effect of Osmotic Stress with PEG6000 on Osmotic Adjustment Solute in Seedling Leaves of Chenopodium album L. 被引量:4
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作者 孙存华 李扬 +5 位作者 贺鸿雁 杜伟 金会丽 王东升 陈湘玲 徐新娜 《Agricultural Science & Technology》 CAS 2007年第3期20-24,共5页
[ Objective] The purpose was to discuss drought resistance mechanism of Chenopodium album L. and supply theoretical basis and practical guidance for artificial cultivation and popularization of C. album. [ Method] C. ... [ Objective] The purpose was to discuss drought resistance mechanism of Chenopodium album L. and supply theoretical basis and practical guidance for artificial cultivation and popularization of C. album. [ Method] C. album seedlings grown to 6th leaf stage were conducted osmotic stress treatment with PEG6000 osmotic whose concentration was set up as 0, 5%, 10% and 20% and the various physiological indices of the 3rd -5th function leaves in upper plant were determined after being treated for 0, 1,3, 5, 7 and 9 d. [ Result] Under osmotic stress with 5% PGE, the relative water content (RWC) of C. album reduced less. Under osmotic stress with 10%, the RWC in seedling leaves of C. album decreased to 62% on the fifth day and the leaves began to wither. Under osmotic stress with 20%, the RWC in seedling leaves of C. album decreased to 61.9% on the third day and the leaves appeared withering, and the RWC decreased to 48.6% on the 7th day and the leaves were dry and yellow. Proline contents in seedling leaves of C. album under osmotic stress with 5%, 10% and 20% PEG were 7.64, 10.9 and 29.4 times of CK on the 7th day. [ Conclusion] C. album hed some adaptability to moderate osmotic stress, but the PEG osmotic stress with high concentration and long time might lead to severe damage on C. album. 展开更多
关键词 Chenopodium album L. PEG osmotic stress osmotic adjustment solute
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Structural characteristics of the epidermis in marine and freshwater finless porpoises adapted to distinct osmotic environments
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作者 Haojie Zhou Changqun Zhang +5 位作者 Bin Tang Haobo Zhang Jinsong Zheng Kexiong Wang Dekui He Yujiang Hao 《Current Zoology》 2025年第3期304-319,共16页
The Yangtze finless porpoise(Neophocaena asiaeorientalis asiaeorientalis,Pilleri&Gihr,1972;YFP)is an exclusively freshwater cetacean species inhabiting the Yangtze River and its connecting large lakes.As the prima... The Yangtze finless porpoise(Neophocaena asiaeorientalis asiaeorientalis,Pilleri&Gihr,1972;YFP)is an exclusively freshwater cetacean species inhabiting the Yangtze River and its connecting large lakes.As the primary line of defense in maintaining physiological equilibrium,the epidermis of the porpoise is expected to have undergone structural adaptations due to the shift from the marine to the freshwater environment.This study compared the microstructural and ultrastructural features of the epidermis of YFP and its marine counterpart,the East Asian finless porpoise(Neophocaena asiaeorientalis sunameri,Pilleri&Gihr,1975;EAFP).Microscopic structural observations and statistical analyses of the epidermal thickness demonstrated no significant differences in the cell structure or distribution between the two porpoise species.However,the epidermis of the YFP contained more abundant stratum basale cells.The outermost lipid stratum corneum exhibited a thinner cell layer with wider neutral lipid droplets to resist the passive entry of water molecules in the hypotonic environment.In contrast,for the EAFp,a more uniformly arranged stratum basale in the epidermis led to denser keratin fibers and robust desmosomes within each epidermal layer at the ultrastructural level.This tight arrangement of cells can reduce transepidermal water loss(TEWL)in an environment with higher osmotic pressure.In conclusion,the 2 finless porpoise species appear to employ different epidermal mechanisms to adapt to their distinct osmotic environments.The YFP appears to possess a"lipid waterproofing"epidermal structure,while the EAFP possesses a"thick and compact water-retaining"epidermal structure to copewithpotentialwaterloss. 展开更多
关键词 EPIDERMIS finless porpoise HISTOLOGY osmotic adaptation stratum basale cells TEWL.
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Osmotic membranes for municipal wastewater reclamation:Insights into applications,transmembrane diffusion mechanisms and prospects
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作者 Yujie Xie Kexin Yuan +3 位作者 Beiyang Luo Haoran Feng Xian Bao Jun Ma 《Chinese Chemical Letters》 2025年第7期23-33,共11页
With the global advancement of the circular economy,integrating reverse osmosis(RO)or forward osmosis(FO)with anaerobic membrane bioreactor(AnMBR)offers a promising approach to simultaneously generate high-grade recla... With the global advancement of the circular economy,integrating reverse osmosis(RO)or forward osmosis(FO)with anaerobic membrane bioreactor(AnMBR)offers a promising approach to simultaneously generate high-grade reclaimed water,produce energy,and preserve valuable nutrients from municipal wastewater.However,the selectivity of these osmotic membranes towards ammonia nitrogen,a major component in municipal wastewater and anaerobic effluent,remains unsatisfactory due to its similar polarity and hydraulic radius to water molecules.Therefore,enhancing the ammonia nitrogen rejection of osmotic membranes is imperative to maximize the quality of reclaimed water and minimize the loss of ammonia nitrogen resources.Unfortunately,the current understanding of the mapping relationship between ammonia nitrogen transmembrane diffusion and the micro/nano-structure of osmotic membranes is not systematic,making precise optimization of the membranes challenging.Hence,this review comprehensively analyzed the diffusion behavior of ammonia nitrogen through osmotic membranes to lay the foundation for targeted regulation of membrane fine structure.Initially,the desire for ammonia/ammonium-rejecting membranes was highlighted by introducing current and promising osmotic membrane-based applications in municipal wastewater reclamation processes.Subsequently,the connection between the micro/nano-structure of osmotic membranes and the transmembrane diffusion behavior of ammonia nitrogen was explored by analyzing the effects of membrane characteristics on ammonia nitrogen transport using the DSPM-DE model.Finally,precise methods for modifying membranes to enhance ammonia nitrogen rejection were proposed.This review aims to offer theoretical insights guiding the development of RO and FO membranes with superior ammonia nitrogen rejection for efficient reclamation of municipal wastewater. 展开更多
关键词 Municipal wastewater reclamation osmotic membrane Ammonia nitrogen selectivity Transmembrane diffusion mechanism Optimization strategies
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Anti-Swelling Polyelectrolyte Hydrogel with Submillimeter Lateral Confinement for Osmotic Energy Conversion
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作者 Yongxu Liu Jiangnan Song +10 位作者 Zhen Liu Jialin Chen Dejuan Wang Hui Zhi Jiebin Tang Yafang Zhang Ningbo Li Weijia Zhou Meng An Hong Liu Guobin Xue 《Nano-Micro Letters》 2025年第4期96-110,共15页
Harvesting the immense and renewable osmotic energy with reverse electrodialysis(RED)technology shows great promise in dealing with the ever-growing energy crisis.One key challenge is to improve the output power densi... Harvesting the immense and renewable osmotic energy with reverse electrodialysis(RED)technology shows great promise in dealing with the ever-growing energy crisis.One key challenge is to improve the output power density with improved trade-off between membrane permeability and selectivity.Herein,polyelectrolyte hydrogels(channel width,2.2 nm)with inherent high ion conductivity have been demonstrated to enable excellent selective ion transfer when confined in cylindrical anodized aluminum pore with lateral size even up to the submillimeter scale(radius,0.1 mm).The membrane permeability of the anti-swelling hydrogel can also be further increased with cellulose nanofibers.With real seawater and river water,the output power density of a three-chamber cell on behalf of repeat unit of RED system can reach up to 8.99 W m^(-2)(per unit total membrane area),much better than state-of-the-art membranes.This work provides a new strategy for the preparation of polyelectrolyte hydrogel-based ion-selective membranes,owning broad application prospects in the fields of osmotic energy collection,electrodialysis,flow battery and so on. 展开更多
关键词 Ionic polymer HYDROGEL Confinement effect Anti-swelling osmotic energy conversion
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A composite hydrogel with porous and homogeneous structure for efficient osmotic energy conversion
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作者 Guilong Li Wenbo Ma +4 位作者 Jialing Zhou Caiqin Wu Chenling Yao Huan Zeng Jian Wang 《Chinese Chemical Letters》 2025年第2期206-210,共5页
With the impact of energy crisis and environmental problems,it is urgent to develop green sustainable energy.Osmotic energy stored in the salinity difference between seawater and river water is one of the sustainable,... With the impact of energy crisis and environmental problems,it is urgent to develop green sustainable energy.Osmotic energy stored in the salinity difference between seawater and river water is one of the sustainable,abundant,and renewable energy.However,the membranes used to capture osmotic energy by reverse electrodialysis(RED)always suffer from low ion selectivity,low stability and low power.Hydrogels with three-dimensional(3D)networks have shown great potential for ion transportation and energy conversion.In this work,based on the homogeneity and porosity characteristics of acrylamide(AM)hydrogel,as well as the remarkable stability and abundant negative charge of 3-sulfopropyl acrylate potassium salt(SPAK),a high-performance AM/SPAK cation-selective hydrogel membrane was successfully developed for harvesting osmotic energy.Compared to AM hydrogels,utilizing AM/SPAK as a monomer mixture greatly facilitated the preparation of homogeneous polymers,exhibiting a porous structure,exceptional ion selectivity,and remarkable stability.A maximum output power density of 13.73 W/m^(2)was achieved at a 50-fold NaCl concentration gradient,exceeding the commercial requirement of 5 W/m^(2).This work broadens the idea for the construction and application of composite hydrogel in high efficiency osmotic energy conversion. 展开更多
关键词 osmotic energy Cation-selective membrane Porous structure STABILITY Power density
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Desiccation and osmotic resistance mechanism of Cronobacter spp.isolated from powdered infant formula
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作者 Shiqian Fu Danliangmin Song +5 位作者 Xue Qin Lihan Wang Qianyu Zhao Chaoxin Man Xinyan Yang Yujun Jiang 《Food Science and Human Wellness》 2025年第3期968-980,共13页
Cronobacter spp.has strong resistance to desiccation and high permeability in Enterobacteriaceae,and powdered infant formula(PIF)is one of the main contamination routes.In recent years,the contamination of Cronobacter... Cronobacter spp.has strong resistance to desiccation and high permeability in Enterobacteriaceae,and powdered infant formula(PIF)is one of the main contamination routes.In recent years,the contamination of Cronobacter spp.in PIF incidents occurs from time to time,causing infant serious diseases or death.In this investigation,matrix-assisted laser desorption/ionization time of flight mass spectrometry was used to identify the phenotypes of 35 Cronobacter strains isolated from PIF and its processing environment.Subsequently,the isolates were evaluated for drying and osmotic pressure tolerance.The results showed that the deactivation rate of the strains ranged from 9.01%to 77.57%,and the highest osmotic pressure condition the strains could tolerate was 6 g/100 mL Na Cl.In addition,there was a positive correlation between biofilm formation ability and desiccation resistance.Combined with transcriptomics,Cronobacter spp.could activate biofilm synthesis,produce more trehalose,accumulate betaine and electrolytes to stabilize intracellular structure under the two treatment conditions.A total of 31 and 43 genes were found related to desiccation and permeability resistance,respectively.And some genes(cysM,thuF,ycjO,etc.)were found to be associated with two tolerances for the first time. 展开更多
关键词 Powdered infant formula Cronobacter spp. Desiccation resistance osmotic resistance TRANSCRIPTOMICS
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Modeling and Experimental Study of an Open Two-Phase Loop Driven by Osmotic Pressure and Capillary Force
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作者 Hanli Bi Zheng Peng +5 位作者 Chenpeng Liu Zhichao Jia Guoguang Li Yuandong Guo Hongxing Zhang Jianyin Miao 《Frontiers in Heat and Mass Transfer》 2025年第1期55-70,共16页
As space technology advances,thermal control systems must effectively collect and dissipate heat from distributed,multi-source environments.Loop heat pipe is a highly reliable two-phase heat transfer component,but it ... As space technology advances,thermal control systems must effectively collect and dissipate heat from distributed,multi-source environments.Loop heat pipe is a highly reliable two-phase heat transfer component,but it has several limitations when addressing multi-source heat dissipation.Inspired by the transport and heat dissipation system of plants,large trees achieve stable and efficient liquid supply under the influence of two driving forces:capillary force during transpiration in the leaves(pull)and root pressure generated by osmotic pressure in the roots(push).The root pressure provides an effective liquid supply with a driving force exceeding 2 MPa,far greater than the driving force in conventional capillary-pumped two-phase loops.Research has shown that osmotic heat pipes offer a powerful driving force,and combining osmotic pressure with capillary force has significant advantages.Therefore,this paper designs a multi-evaporator,dual-drive two-phase loop,using both osmotic pressure and capillary force to solve the multi-source heat dissipation challenge.First,a transmembrane water flux model for the osmotic pressure-driven device was established to predict the maximum heat transfer capacity of the dual-drive two-phase loop.Then,an experimental setup for a multi-evaporator“osmotic pressure+capillary force”dual-drive two-phase loop was constructed,capable of transferring at least 235 W of power under a reverse gravity condition of 20 m.The study also analyzed the effects of reverse gravity height,heat load distribution among the three evaporators,startup sequence,and varying branch resistances on the performance of the dual-drive two-phase loop. 展开更多
关键词 Multi-heat sources osmotic pressure two-phase loop dual-drive loop heat pipe
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Effects of Nitric Oxide on the Germination of Wheat Seeds and Its Reactive Oxygen Species Metabolisms Under Osmotic Stress 被引量:51
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作者 张华 沈文飚 徐朗莱 《Acta Botanica Sinica》 CSCD 2003年第8期901-905,共5页
Effects of sodium nitroprusside (SNP), a nitric oxide (NO) donor, on the germination and metabolism of reactive oxygen species were surveyed in wheat (Triticum aestivum L.) seeds. Germination of wheat seeds and even t... Effects of sodium nitroprusside (SNP), a nitric oxide (NO) donor, on the germination and metabolism of reactive oxygen species were surveyed in wheat (Triticum aestivum L.) seeds. Germination of wheat seeds and even the elongation of radicle and plumule were dramatically promoted by SNP treatments during the germination under osmotic stress. Meanwhile, activities of amylase and EP were enhanced, thus leading to the degradation of storage reserve in seeds. After osmotic stress was removed, higher viability of wheat seeds was also maintained. In addition, the activities of CAT, APX and the content of proline were increased by SNP treatment simultaneously, but activities of LOX were inhibited, and both of which were beneficial for improving the antioxidant capacity during the germination of wheat seeds under osmotic stress. It was also shown that the increase of the activity of amylase induced by SNP in embryoless half-seeds of wheat in the beginning period of germination (6 h) might be indirectly related to GA(3). 展开更多
关键词 nitric oxide (NO) wheat seed germination osmotic stress storage reserve degradation reactive oxygen species metabolism gibberellin (GA(3))
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Effects of Polyamine on Leaf Physiological and Biochemical Indexes of Maize Seedlings under Osmotic Stress 被引量:7
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作者 宋维贤 杜红阳 +2 位作者 常云霞 刘怀攀 李潮海 《Agricultural Science & Technology》 CAS 2010年第1期19-20,24,共3页
[Objective]The research aimed to probe into the mechanism of polyamine enhancing the tolerance of plants to drought stress and provide theoretical basis for application of polyamine in process of maize drought resista... [Objective]The research aimed to probe into the mechanism of polyamine enhancing the tolerance of plants to drought stress and provide theoretical basis for application of polyamine in process of maize drought resistance. [Method]With PEG-6000 simulating natural drought,the change in content of soluble protein and relative water content were investigated in seedling leaves of two maize cultivars,Nongda 108 and Yedan 13 under osmotic stress with exogenous Spd treatment. [Result]On the 7th day,leaf relative water content and the content of soluble protein decreased more significantly in leaves of Yedan 13 (drought-sensitive) than in Nongda 108 (drought-tolerant). Exogenous Spd treatment not only obviously inhibited the decrease of leaf relative water content,but also increased the content of soluble protein. [Conclusion]Exogenous Spd treatment could enhance the tolerance of maize seedlings to osmotic stress,via improving the content of soluble protein in seedling leaves. 展开更多
关键词 osmotic stress MAIZE POLYAMINE Soluble protein
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Preparation of monolithic osmotic tablet of quercetin loaded by solid dispersion 被引量:3
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作者 郝海军 贾幼智 +4 位作者 张红芹 韩茹 王雪萍 韩丽妹 王建新 《Journal of Chinese Pharmaceutical Sciences》 CAS CSCD 2015年第6期383-392,共10页
The objective of this study was to prepare monolithic osmotic tablet of quercetin for controlled drug release. Quercetin-PVP solid dispersion was prepared to enhance its solubility and dissolution rate. Solid dispersi... The objective of this study was to prepare monolithic osmotic tablet of quercetin for controlled drug release. Quercetin-PVP solid dispersion was prepared to enhance its solubility and dissolution rate. Solid dispersion, suspending agents, osmotic agents and other conventional excipients were used as tablet core composition and cellulose acetate (CA) with plasticizer as release controlling membrane. Different formulation variables, the amounts of PEO (polyethylene oxide), NaC1, plasticizer, and coating weight gain were optimized to gain the optimum formulation. The mechanism of drug release from monolithic osmotic tablet was also discussed. The optimal monolithic osmotic pump tablet could deliver quercetin at the rate of approximate zero-order up to 12 h, and the cumulative release was 90.74%. The developed monolithic osmotic system for quercetin loaded by solid dispersion was found to be a promising approach for controlled release of poorly-water soluble drug candidates. 展开更多
关键词 QUERCETIN Solid dispersion Monolithic osmotic tablet Controlled drug delivery system
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Response of Photosynthesis, Growth, Carbon Isotope Discrimination and Osmotic Tolerance of Rice to Elevated CO_2 被引量:3
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作者 彭长连 段俊 +2 位作者 林桂珠 陈贻竹 彭少麟 《Acta Botanica Sinica》 CSCD 2002年第1期76-81,共6页
Four rice ( Oryza sativa L.) cultivars 'IR72', 'Tesanai 2', 'Guichao 2' and 'IIyou 4480' were grown in two plastic house (15 m×3 m) with 35 μmol/mol and 60 μmol/mol CO 2 conc... Four rice ( Oryza sativa L.) cultivars 'IR72', 'Tesanai 2', 'Guichao 2' and 'IIyou 4480' were grown in two plastic house (15 m×3 m) with 35 μmol/mol and 60 μmol/mol CO 2 concentration which was controlled by computer. As compared with rice at ambient 35 μmol/mol CO 2, the changes in photosynthetic rate at elevated CO 2 showed up_regulation ('IR72' and 'Tesanai 2'), stable (unchanged) in 'Guichao 2' and down_regulation type ('IIyou 4480'). Growth rate, panicle weight, integrated water use efficiency (WUE) calculated from Δ 13 C and the capacity of scavenging DPPH · (1,1_diphenyl_2_picrylhydrazyl) free radical were increased at elevated CO 2. An increment in total biomass was observed in three cultivars by elevated CO 2, with the exception of 'IIyou 4480'. Ratios of panicle weight/total biomass were altered to different extents in tested cultivars by elevated CO 2. When leaf segments were subjected to PEG osmotic stress, the electrolyte leakage rate from leaves grown at elevated CO 2 was less than that at 35 μmol/mol CO 2. Those intraspecific variations of rice imply a possibility for selecting cultivars with maximal productivity and high tolerance to stresses adapted to elevated CO 2 in the future. 展开更多
关键词 rice cultivars elevated CO 2 PHOTOSYNTHESIS water use efficiency 13 C discrimination osmotic tolerance
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Effects of Drought Stress on Osmotic Regulation Substances of Five Catalpa bungei Clones 被引量:3
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作者 董蕾 李吉跃 +2 位作者 王军辉 谢堃 苏艳 《Agricultural Science & Technology》 CAS 2013年第9期1335-1343,共9页
[Objective] This study aimed to investigate the effects of drought stress on osmotic regulation substances of Catalpa bungei clones. [Method] Potting experimental was carried out with plastic film sealing method, to d... [Objective] This study aimed to investigate the effects of drought stress on osmotic regulation substances of Catalpa bungei clones. [Method] Potting experimental was carried out with plastic film sealing method, to differentiate the degrees of drought stress based on changes in soil water content and leaf water potential and investigate variations in contents of osmotic regulation substances(free proline,soluble sugar and soluble protein) in leaves of five Catalpa bungei clones under different degrees of drought stresses. [Result] According to changes in soil water content and leaf water potential, the whole process of drought stress was divided into normal level(CK, with soil water content of 97.49% and leaf water potential of-0.54MPa), light drought(LD with soil water content of 59.96% and leaf water potential of-1.28 MPa), mediate drought(MD with soil water content of 34.19% and leaf water potential of-2.32 MPa) and severe drought(SD with soil water content of 14.52%and leaf water potential of-2.99 MPa). The soil water content and leaf water potential of five Catalpa bungei clones reached the highest correlation in exponential fitting, with an average R2of 0.989 3(P0.001). The free proline content in leaves of five Catalpa bungei clones increased rapidly with the increasing degree of drought stress(P 0.001). To be specific, free proline contents of Catalpa bungei clones015-1 and 7080 were 34.39 and 33.41 times of the normal level under severe drought conditions, which reached an extremely significant level(P0.001); the free proline content of Catalpa bungei clone 1-3 rapidly increased to(855.46±227.52) μg/g Fw under light drought conditions. The soluble protein content in leaves showed different variation trends. To be specific, the soluble protein content of Catalpa bungei clone 7080 was the lowest at various drought stages and reached(1.644 ±0.137)mg/g Fw under normal conditions; the soluble protein content of Catalpa bungei clone 1-3 was relatively high under normal conditions and was reduced rapidly under light drought conditions, showing different response patterns. [Conclusion] Osmotic regulation substances in leaves of five Catalpa bungei clones all have certain response to drought stress. Free proline is the most important osmotic regulation substance, followed by soluble protein, while soluble sugar makes no significant contribution. According to changes in content of osmotic regulation substances, Catalpa bungei clone 7080 has relatively high capacity and good drought resistance, while Catalpa bungei clone 1-3 has the rapidest response to drought stress. 展开更多
关键词 Drought stress Catalpa bungei clones osmotic regulation substances
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Mechanism of Drug Release from Compound Metformin/Glipizide Elementary Osmotic Pump Tablets 被引量:1
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作者 欧阳德方 孟晋 +2 位作者 孔翠凤 聂淑芳 潘卫三 《Journal of Chinese Pharmaceutical Sciences》 CAS 2006年第2期92-96,共5页
In previous studies, compound mefformin/glipizide was developed. Aim To discover the mechanism of drug release from factors influencing drug release from dosage form (the semi-permeable cry orifice) were investigate... In previous studies, compound mefformin/glipizide was developed. Aim To discover the mechanism of drug release from factors influencing drug release from dosage form (the semi-permeable cry orifice) were investigated. Results The influx of water that elementary osmotic pump tablet it. Methods Three rate-limiting membrane, tablet core and delivpassed the osmotic pump tablet was almost equal to the metformin release rate, while it was greatly less than the drug dissolution rate from tablet core. The size of orifice from 0. 4 mm to 0.8 mm had no influence on drug release. The osmotic pressure of tablet core was mainly caused by mefformin. Conclusion From the developed model of osmotic pump systems, it can be seen that only the water influx through the membrane is a rate-limiting step, not tablet core dissolution rate and solution influx, and only when the core dissolution rate is equal to the solution influx, the zero order release is seen in the osmotic pump systems. 展开更多
关键词 METFORMIN GLIPIZIDE osmotic pump MECHANISM
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OSMOTIC STRESS DECREASES THE ACTIVITY OF ATPASE ASSOCIATED WITH THE ROOT CAP PLASMODESMATAIN ZEA MAYS 被引量:1
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作者 苗龙 王学臣 张伟成 《Acta Botanica Sinica》 CSCD 1997年第8期774-777,共4页
With light and electron microscopy the substructural change and the ATPase activity of corn (Zea mays L.) root cap cells after short-term osmotic stress were studied. Some spoke-like fine strands originating from the ... With light and electron microscopy the substructural change and the ATPase activity of corn (Zea mays L.) root cap cells after short-term osmotic stress were studied. Some spoke-like fine strands originating from the departed periplasm and stretching towards cell wall could be observed even after plasmolysis. By observing the precipitation of ATPase activity product (lead phosphate) at plasma membrane and plasmodesmata, it was found that the fine strands were plasma membrane-lined channels surrounding the cytoplasm and that they still firmly connected to the plasmodesmata during plasmolysis. Compared with the control (unstressed), a sharp decrease of ATPase activity in the plasmodesmata of the stressed cells was observed. Inhibition of energy metabolism in these limited locales would affect the physiological activity, maybe including the regulation of permeability and the change of size exclusion limit (SEL) of plasmodesmata. 展开更多
关键词 ATPASE osmotic stress PLASMODESMATA Zea mays
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The clinical pharmacokinetics of osmotic pump controlled release tablets of terazosin hydrochloride in healthy volunteers
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作者 马廷升 李高 +2 位作者 杨光忠 刘志华 朱兰寸 《Journal of Chinese Pharmaceutical Sciences》 CAS 2011年第3期253-258,共6页
The clinical pharmacokinetics of osmotic pump controlled release tablets of terazosin hydrochloride in healthy volunteers was studied.A sensitive and rapid HPLC method was used to determine the terazosin plasma concen... The clinical pharmacokinetics of osmotic pump controlled release tablets of terazosin hydrochloride in healthy volunteers was studied.A sensitive and rapid HPLC method was used to determine the terazosin plasma concentrations,and single and multiple doses of terazosin hydrochloride regular tablets(reference tablets)and osmotic pump controlled release tablets were orally administrated in randomized crossover design.The results showed that the C_(max)of the reference tablets after single oral dose((120.56±23.15)ng/mL)in 20 healthy volunteers was significantly higher than that of controlled release tablets ((95.27±16.35)ng/mL).The T_(max)of the controlled release tablets((2.65±0.82)h)was significantly longer than that of reference tablets((1.27±0.61)h)(P0.05).The relative bioavailability of the controlled release tablets was found to be(105.85±6.12)%. The multiple oral dose pharmacokinetic parameters of the regular tablets and controlled release tablets were as follows:AUC_(SS) were(1275.17±175.35)and(1382.65±205.31)ng·h/mL respectively,C_(max)were(128.15±22.37)and(98.57±18.16)ng/mL respectively,T_(max)were(1.35±0.71)and(2.76±0.85)h respectively,C_(av)were(53.13±9.12)and(57.61±9.25)ng/mL respectively, and DF were(2.25±0.26)%and(1.62±0.25)%respectively.The relative bioavailability of the controlled release tablets to the reference tablets was(108.43±6.26)%.The controlled release tablet of terazosin hydrochloride was bioequivalent to the reference tablet.The controlled release tablet exhibited a sustained-release property with a significantly longer T_(max)and lower C_(max). 展开更多
关键词 Terazosin hydrochloride osmotic pump system Controlled release tablets PHARMACOKINETICS BIOEQUIVALENCE
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Relationship between ATPase activity and conjugated polyamines in mito-chondrial membrane from wheat seedling roots under osmotic stress 被引量:16
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作者 LIUHuai-pan LIUJun ZHANGYan-yan LIUYou-liang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2004年第5期712-716,共5页
The effects of osmotic stress on the ATPase activity, the contents of —SH group and conjugated polyamines in mitochondrial membrane from wheat seedling [Triticum aestivum L. cv. Yumai No.18(drought-tolerant) and cv. ... The effects of osmotic stress on the ATPase activity, the contents of —SH group and conjugated polyamines in mitochondrial membrane from wheat seedling [Triticum aestivum L. cv. Yumai No.18(drought-tolerant) and cv. Yumai No.9(drought-sensitive)] roots were investigated. The results showed that ATPase activity and —SH group content decreased with polyethylene glycol(PEG) 6000(-0.55 MPa) treatment for 7 d, in concert with the decrease of the ratio of noncovalently conjugated spermidine(NCC-Spd)/noncovalently conjugated putrescine(NCC-Put) and increase of the covalently conjugated putrescine(CC-Put). Osmotic stress injury to Yangmai No.9 seedlings was alleviated greatly with 1 mmol/L exogenous spermidine(Spd), in concert with marked increases of the ratio of NCC-Spd/NCC-Put, —SH group contents and ATPase activity in mitochondrial membrane. Under osmotic stress, the concomitant treatment of Yumai No.18 seedlings with methylglyoxyl bis(guanylhydrazone) (MGBG), an inhibitor of S-adenosyl methionine decarboxylase(SAMDC), and phenanthrolin (o-Phen), an inhibitor of transglutaminase(TGase), caused a significant decrease of the ratio of NCC-Spd / NCC-Put, CC-Put contents, respectively, in concert with the marked decreases of ATPase activity, —SH group content and its tolerance to osmotic stress. All the results above suggested that osmotic stress tolerance of wheat seedlings was associated with the ATPase activity, the contents of —SH group, NCC-Spd and CC-Put in mitochondrial membrane. 展开更多
关键词 ATPASE conjugated polyamines MITOCHONDRIA osmotic stress wheat(Triticum aestivum L.)
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Double-layered osmotic pump controlled release tablets of actarit: In vitro and in vivo evaluation 被引量:9
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作者 Yuenan Li Hao Pan +6 位作者 Hongliang Duan Jianting Chen Zhihong Zhu Jingxin Fan Pingfei Li Xinggang Yang Weisan Pan 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2019年第3期340-348,共9页
The aim of the study was to develop actarit double-layered osmotic pump tablets to overcome the weak points of actarit common tablets, such as short half-life and large plasma concentration fluctuations. Single factor... The aim of the study was to develop actarit double-layered osmotic pump tablets to overcome the weak points of actarit common tablets, such as short half-life and large plasma concentration fluctuations. Single factor experiment and orthogonal test were applied to optimize the formulation;the pharmacokinetic study was performed in beagle dogs adopting actarit common tablets as reference tablets. The optimal formulation was as follows: drug layer: 150 mg actarit, 240 mg PEO-N80, 50 mg NaCl;push layer: 140 mg PEO-WSR303, 20 mg NaCl;coating solution: 30 g cellulose acetate and 6 g PEG 4000 in 1000 ml 94% acetone solution, 60 mg coating weight gain. The pharmacokinetic study showed that T max was prolonged by the contrast of commercial common tablets with constant drug release rate, but the bioavailability was equivalent. And a good in vivo –in vitro correlation of the actarit osmotic pump tablets was also established. The designed actarit osmotic pump tablets can be applied for rheumatoid arthritis, proposing a promising replacement for the marked common products. 展开更多
关键词 Actarit Double-layered osmotic pump TABLET PHARMACOKINETICS In vivo –in VITRO correlation
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Effects of osmotic stress on antioxidant enzymes activities in leaf discs of P_(SAG12)-IPT modified gerbera 被引量:6
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作者 LAI Qi-xian BAO Zhi-yi +2 位作者 ZHU Zhu-jun QIAN Qiong-qiu MAO Bi-zeng 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2007年第7期458-464,共7页
Leaf senescence is often caused by water deficit and the chimeric gene PSA612-1PT is an auto-regulated gene delaying leaf senescence. Using in vitro leaf discs culture system, the changes of contents of chlorophylls, ... Leaf senescence is often caused by water deficit and the chimeric gene PSA612-1PT is an auto-regulated gene delaying leaf senescence. Using in vitro leaf discs culture system, the changes of contents of chlorophylls, carotenoids, soluble protein and thiobarbituric acid reactive substance (TBARS) and antioxidant enzymes activities were investigated during leaf senescence of PSA612-1PT modified gerbera induced by osmotic stress compared with the control plant (wild type). Leaf discs were incubated in 20%, 40% (w/v) polyethylene glycol (PEG) 6 000 nutrient solution for 20 h under continuous light [ 130 μmol/(m^2·s)]. The results showed that the contents of chlorophylls, carotenoids and soluble protein were decreased by osmotic stress with the decrease being more pronounced at 40% PEG, but that, at the same PEG concentration the decrease in the transgenic plants was significantly lower than that in the control plant. The activities of superoxide dismutase (SOD), catalases (CAT), ascorbate peroxidase (APX), guaiacol peroxidase (GPX) and dehydroascorbate reductase (DHAR) were stimulated by PEG treatment. However, the increases were higher in PSA612-IPT transgenic plants than in the control plants, particularly at 40% PEG treatment. Lipid peroxidation (TBARS content) was increased by PEG treatment with the increase being much lower in transgenic plant than in the control plant. It could be concluded that the increases in the activities ofantioxidant enzymes including SOD, CAT, APX, GPX and DHAR were responsible for the delay of leaf senescence induced by osmotic stress. 展开更多
关键词 Antioxidant enzymes GERBERA Leaf disc Leaf senescence osmotic stress PSAG12-IPT
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Effects of lanthanum on the growth and essential oil components of lavender under osmotic stress 被引量:6
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作者 Liyun Zhu Linzhen Song +3 位作者 Yongsheng Gao Junqing Qian Xiaodong Zhang Sufang Li 《Journal of Rare Earths》 SCIE EI CAS CSCD 2018年第8期891-897,共7页
The effects of lanthanum on growth, soluble sugar content, essential oil contents and quality were studied in lavender plant(Lavandula Angustifolia Mill, Variety 701) under osmotic stress by means of PEG-6000 soluti... The effects of lanthanum on growth, soluble sugar content, essential oil contents and quality were studied in lavender plant(Lavandula Angustifolia Mill, Variety 701) under osmotic stress by means of PEG-6000 solution. The results show that osmotic stress could reduce the growth rate of lavender, and increase the content of SSC(soluble sugar concentration) to some extent. Compared with control group,the contents of essential oil in flowers and leaves respectively increase by 45.6% and 48.3% in the osmotic stress group induced by 15% PEG-6000. However, the presence of lanthanum can make the contents of essential oil in the flowers and leaves of stressed lavender plants enhance by 19.4% and 18.6%, respectively. Under osmotic stress, the relative contents of four kinds of lavender essential oil compositions of camphor, linalool, linalyl acetate and lavandulol acetate in the lavender flowers were successively 22.63%,0.61%,25.46%,7.03%,and 20.17%,0.62%,20.72%,10.80%,respectively in the presence and absence of lanthanum. The contents of all four main components of lavender essential oils meet the requirements of the national standard under osmotic stress in the presence of lanthanum. However, in the absence of lanthanum, the contents of linalyl acetate and lavandulol acetate does not meet the requirements of the national standard under osmotic stress. Moreover, the contents of five components of borneol, camphor,eudesmol, caryophyllene oxide and bicyclic sesquiphellandrene from the essential oil of lavender leaves are 12.89%, 3.84%, 8.76%, 11.30% and 8.10%, respectively. The total content of above five components accounts for 44.89% of the essential oil of the lavender leaves. Particularly, the borneol content in leaf essential oil is up to 12.89%. It is 125.2 times the amount of borneol in the flower essential oil. In conclusion, the suitable concentration of lanthanum can improve the adaptability of lavender plants, and heighten the content and quality of lavender essential oil to some extent under osmotic stress. 展开更多
关键词 LANTHANUM LAVENDER Essential oil Secondary metabolites osmotic stress Rare earths
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