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Optimization on Production Key Factors of Microbial Fermented Feed and Analysis on Composition Variation During Fermentation 被引量:4
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作者 Lin Biaosheng Luo Jian +3 位作者 Li Yiming He Yuqin Luo Maochun Yang Xiaoyan 《Animal Husbandry and Feed Science》 CAS 2017年第3期179-183,194,共6页
[ Objective] In order to study the production key factors of microbial fermented feed and the composition variation during fermentation. [ Methods ] Water, temperature, energy and protein were selected to study the ef... [ Objective] In order to study the production key factors of microbial fermented feed and the composition variation during fermentation. [ Methods ] Water, temperature, energy and protein were selected to study the effects on microbial fermented feed. And the fermentation conditions were optimized. Changes on nutrient composition during fermentation were determined and analyzed. [ Result ] Test results showed that feed formula with high sugar content, low protein, 34% - 36% water content, high fermentation temperature was more conducive to the production and actual production needs of fermentation strains. During the fermentation, strains showed interactions, test tended to be completed at the 144^th h after the fermentation, and number of lactic acid bacteria reached the peak of 1.86×10^9 strain/g, contents of lactic acid could even reach 0.89%. As time prolonged, contents of total energy, fiber and isothiocyanate gradually reduced, while contents of water and protein increased slightly. Contents of vitamin were stable, which in an order of VB〉 VE 〉 Vx 〉 VA 〉 VD. Composition of amino acids showed an better change, contents of glutamic acid and proline decreased slowly, while contents of glycine and phenylalanine increased slowly. [ Conclusion] High quality microbial fermentation feed could improve the palatability and safety of feed and keep the intestinal balance of livestock and poultry, which had broad application prospect. 展开更多
关键词 Microbes Fermented feed key factors Composition variation ANALYSIS
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Study of the key factors affecting the triple grid lifetime of the LIPS-300 ion thruster 被引量:1
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作者 孙明明 王亮 +3 位作者 杨俊泰 温晓东 黄永杰 王蒙 《Plasma Science and Technology》 SCIE EI CAS CSCD 2018年第4期152-163,共12页
In order to ascertain the key factors affecting the lifetime of the triple grids in the LIPS-300 ion thruster,the thermal deformation,upstream ion density and component lifetime of the grids are simulated with finite ... In order to ascertain the key factors affecting the lifetime of the triple grids in the LIPS-300 ion thruster,the thermal deformation,upstream ion density and component lifetime of the grids are simulated with finite element analysis,fluid simulation and charged-particle tracing simulation methods on the basis of a 1500 h short lifetime test.The key factor affecting the lifetime of the triple grids in the LIPS-300 ion thruster is obtained and analyzed through the test results.The results show that ion sputtering erosion of the grids in 5 kW operation mode is greater than in the case of 3 kW.In 5 kW mode,the decelerator grid shows the most serious corrosion,the accelerator grid shows moderate corrosion,and the screen grid shows the least amount of corrosion.With the serious corrosion of the grids in 5 kW operation mode,the intercept current of the acceleration and deceleration grids increases substantially.Meanwhile,the cold gap between the accelerator grid and the screen grid decreases from 1 mm to 0.7 mm,while the cold gap between the accelerator grid and the decelerator grid increases from 1 mm to 1.25 mm after 1500 h of thruster operation.At equilibrium temperature with 5 k W power,the finite element method(FEM)simulation results show that the hot gap between the screen grid and the accelerator grid reduces to 0.2 mm.Accordingly,the hot gap between the accelerator grid and the decelerator grid increases to 1.5 mm.According to the fluid method,the plasma density simulated in most regions of the discharge chamber is 1?×?10;-8?×?10;m;.The upstream plasma density of the screen grid is in the range 6?×?10;-6?×?10;m;and displays a parabolic characteristic.The charged particle tracing simulation method results show that the ion beam current without the thermal deformation of triple grids has optimal perveance status.The ion sputtering rates of the accelerator grid hole and the decelerator hole are 5.5?×?10;kg s;and 4.28?×?10;kg s;,respectively,while after the thermal deformation of the triple grids,the ion beam current has over-perveance status.The ion sputtering rates of the accelerator grid hole and the decelerator hole are 1.41?×?10;kg s;and 4.1?×?10;kg s;,respectively.The anode current is a key factor for the triple grid lifetime in situations where the structural strength of the grids does not change with temperature variation.The average sputtering rates of the accelerator grid and the decelerator grid,which were measured during the 1500 h lifetime test in5 k W operating conditions,are 2.2?×?10;kg s;and 7.3?×?10;kg s;,respectively.These results are in accordance with the simulation,and the error comes mainly from the calculation distribution of the upstream plasma density of the grids. 展开更多
关键词 the triple grids LIFETIME ion thruster key factor
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Future Drought Changes in China Projected by the CMIP6 Models:Contributions from Key Factors 被引量:2
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作者 Qingxin CHEN Tianbao ZHAO +3 位作者 Lijuan HUA Jinhua YU Yafang WANG Chuan XU 《Journal of Meteorological Research》 SCIE CSCD 2023年第4期454-468,共15页
Model simulations show that drought may become more severe and widespread in the 21st century due to humaninduced global warming. However, the contributions from the key factors to the model-projected drought changes ... Model simulations show that drought may become more severe and widespread in the 21st century due to humaninduced global warming. However, the contributions from the key factors to the model-projected drought changes in China have not yet been examined in detail. We used the self-calibrated Palmer Drought Severity Index with Penman–Monteith potential evapotranspiration(scPDSIpm) based on 10 model simulations selected from the Coupled Model Intercomparison Project Phase 6(CMIP6). We investigated the contributions from precipitation(P), near-surface air temperature and specific humidity [Δ(T + q)], net surface longwave radiation(LW), net surface shortwave radiation(SW), and wind speed(WS) to the future changes in scPDSIpm, including the long-term mean, drying area,probability distribution function(PDF), drought frequency, and drought duration based on the scPDSIpm over China.Our results show that model-projected drying mainly occurs over southern China, whereas the dry areas under drought conditions increase from 20% to about 23%/30% under the two scenarios of the shared socioeconomic pathway(SSP2-4.5/SSP5-8.5) from 1985 to 2100, despite large uncertainties in individual projections partly due to internal variability. Drought frequency is projected to increases by about 10%–54%(15%–88%) under the SSP2-4.5(SSP5-8.5) scenario by the late 21st century, along with increases in drought duration. These changes are accompanied by a decrease in the mean scPDSIpm and flattening of the PDFs. The changes in drying over southern China are mainly attributed to surface warming and the increased surface vapor pressure deficit(VPD), with small contributions from changes in the surface net radiation. The changes in wetting over northern China mostly result from increased precipitation along with a small wetting effect from the changes in wind speed. 展开更多
关键词 DROUGHT future projection key factors China Coupled Model Intercomparison Project Phase 6
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Key Human Factors of Vehicle Interior Occupant Packaging in SAE Standard
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作者 丁祎 胡平 +1 位作者 靳春宁 吴晓军 《Journal of Beijing Institute of Technology》 EI CAS 2007年第1期38-44,共7页
Fourteen SAE standards related to accommodation and occupant' packaging for vehicle interior are studied. The influencing factors, key reference accommodation points and major design dimensions and their relationship... Fourteen SAE standards related to accommodation and occupant' packaging for vehicle interior are studied. The influencing factors, key reference accommodation points and major design dimensions and their relationships of occupant packaging and ergonomics during the vehicle interior layout design and development are analyzed. Prototypes are presented to verify the results and how to achieve the packaging is shown. Auto- mobile designers can achieve significant practical guidance for human safety, efficiency accommodation and occupant packaging of all passengers during the vehicle design process. 展开更多
关键词 vehicle interior occupant packaging vehicle layout design and verification key design factors
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Study on the Key Influence Factors of Environmental Mass Incidents by Delphi-PCA-Frequency Analysis Composite Method
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作者 Chuai Xiaoming HAN Jingwen +1 位作者 Zhou Ying Wang Jiajia 《Meteorological and Environmental Research》 CAS 2018年第3期54-59,共6页
In order to prevent and control environmental mass incidents,by comprehensively using literature research,case analysis and logical reasoning method,27 factors influencing environmental mass incidents were selected. A... In order to prevent and control environmental mass incidents,by comprehensively using literature research,case analysis and logical reasoning method,27 factors influencing environmental mass incidents were selected. Among them,15 key influencing factors were screened by Delphi-PCA-frequency analysis composite method. The key influencing factors were analyzed,and corresponding countermeasures were put forward. 展开更多
关键词 Environmental mass incidents Delphi-PCA-frequency analysis key influence factors
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R & D A Key Driving Factor of the Pipeline Industry
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《China Oil & Gas》 CAS 1999年第4期239-240,共2页
Kalamay-Dushanzioilpipelinebuiltin1958isthefirstlongdistanceoilpipelineofChina.Since1960s,withthedevelopmentofDaqing,Shengli,HuabeiandZhongyuanoilfields,oilpipelinenetworkscoveringnortheast,eastChina,andnorthChinahave... Kalamay-Dushanzioilpipelinebuiltin1958isthefirstlongdistanceoilpipelineofChina.Since1960s,withthedevelopmentofDaqing,Shengli,HuabeiandZhongyuanoilfields,oilpipelinenetworkscoveringnortheast,eastChina,andnorthChinahavebeensetup.Withthedevelopmentofnat... 展开更多
关键词 D A key Driving Factor of the Pipeline Industry
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Welding of 2205 duplex stainless steel natural gas pipeline 被引量:5
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作者 李为卫 许晓锋 +2 位作者 杨扬 刘亚旭 胡美娟 《China Welding》 EI CAS 2016年第3期49-56,共8页
There are abundant natural gas resources in western China, but many oil and gas fields are rich in chloridion, sulfureted hydrogen, carbon dioxide and other corrosive medium, which have strong corrosivity to pipeline.... There are abundant natural gas resources in western China, but many oil and gas fields are rich in chloridion, sulfureted hydrogen, carbon dioxide and other corrosive medium, which have strong corrosivity to pipeline. One gas field possesses abundant natural gas with great pressure, and the chloridion concentration in the water separated from gas is about 10% , so the medium has great corrosivity. In order to ensure the safety of the pipeline, about 13 km length pipeline and the internal pipes of a gas treatment plant that purifies gas about 12 billion cubic meter a year are made of 2205 duplex stainless steel (2205 DSS ) . 2205 DSS has many characteristics in welding with complex welding process; and because of high quality requirements for the construction of natural gas pipeline and restriction of on-site conditions, the site welding is very difficult. Around the engineering application, a large number of experimental researches have been carried out on the material microstructure, properties and weldability. Finally welded joints which conform to the requirements of standard are obtained, contributing to the first large-scale application of this material in the field of oil and gas pipelines. Considering the engineering application and the latest research development, the welding and key factors affecting the joint properties of 2205 DSS pipes are summarized and analyzed. 展开更多
关键词 duplex stainless steel WELDABILITY key factors PROPERTY
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A hydrocarbon enrichment model and prediction of favorable accumulation areas in complicated superimposed basins in China 被引量:16
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作者 Pang Xiongqi Meng Qingyang +2 位作者 Jiang Zhenxue Liu Luofu Lu Xiuxiang 《Petroleum Science》 SCIE CAS CSCD 2010年第1期10-19,共10页
The geologic conditions of superimposed basins in China are very complicated. This is mainly shown by multi-phase structural evolution, multiple sets of source-reservoir-cap rock combinations, multiple stages of hydro... The geologic conditions of superimposed basins in China are very complicated. This is mainly shown by multi-phase structural evolution, multiple sets of source-reservoir-cap rock combinations, multiple stages of hydrocarbon generation and expulsion from source rocks, multi-cycle hydrocarbon enrichment and accumulation, and multi-phase reservoir adjustment and reconstruction. The enrichment, accumulation and distribution of hydrocarbon is mainly controlled by the source rock kitchen, paleo- anticline, regional cap rock and intensity of tectonic movement. In this paper, the T-BCMS model has been developed to predict favorable areas of hydrocarbon accumulation in complicated superimposed basins according to time and spatial relationships among five key factors. The five factors include unconformity surface representing tectonic balancing (B), regional cap rock representing hydrocarbon protection (C), paleo-anticline representing hydrocarbon migration and accumulation (M), source rock kitchen representing hydrocarbon generation and expulsion (S) and geological time (T). There are three necessary conditions to form favorable areas of hydrocarbon accumulation. First, four key factors BCMS should be strictly in the order of BCMS from top to bottom. Second, superimposition of four key factors BCMS in the same area is the most favorable for hydrocarbon accumulation. Third, vertically ordered combination and superimposition in the same area of BCMS should occur at the same geological time. The model has been used to predict the most favorable exploration areas in Ordovician in the Tarim Basin in the main hydrocarbon accumulation periods. The result shows that 95% of the discovered Ordovician hydrocarbon reservoirs are located in the predicted areas, which indicates the feasibility and reliability of the key factor matching T-BCMS model for hydrocarbon accumulation and enrichment. 展开更多
关键词 Complicated superimposed basin key factor matching T-BCMS model favorable area for hydrocarbon accumulation hydrocarbon distribution prediction
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Removal of a type of endocrine disruptors—di-n-butyl phthalate from water by ozonation 被引量:7
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作者 LI Hai-van QU Jiu-hui LIU Hui-juan 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2006年第5期845-851,共7页
Ozonation of synthetic water containing a type of endocrine disruptor-di-n-butyl phthalate (DBP) was examined. Key impact factors such as pH, temperature, ionic strength, ozone dosage and initial DBP concentration w... Ozonation of synthetic water containing a type of endocrine disruptor-di-n-butyl phthalate (DBP) was examined. Key impact factors such as pH, temperature, ionic strength, ozone dosage and initial DBP concentration were investigated. In addition, the activities of radicals on uncatalysed and catalysed ozonation were studied. The degradation intermediate products were followed and the kinetic of the ozonation were assessed as well. Results revealed that ozonation of DBP followed two mechanisms. Firstly, the reaction rate of direct ozonation was slower at lower pH, temperature, and ionic strength. Secondly, when these factors were increased for indirect radical reaction, higher percentage of DBP was removed with the increase of the initial ozone dosage and the decrease of the initial DBP concentration. In addition, tea-butanol, humic substances and Fe(Ⅱ) affected DBP ozonation through the radical pathway. It was determined that ozonation was restrained by adding tea-butanol for its radical inhibition effect. Furthermore, humic substances enhanced the reaction to some extent, but a slight negative effect would be encountered if the optimum dosage was exceeded. As a matter of fact, Mn(Ⅱ) affected the ozonation by "active sites" mechanism. In the experiment, three different kinds of intermediate products were produced during ozonation, but the amount of products for each one of them decreased as pH, temperature, ionic strength and initial ozone dosage increased. A kinetic equation of the reaction between ozone and DBP was obtained. 展开更多
关键词 di-n-butyl phthalate (DBP) OZONATION key impact factors reaction kinetics degradation intermediate products
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Identifying Summer/Autumn Habitat Hotspots of Jumbo Flying Squid (Dosidicus gigas) off Chile
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作者 YU Wei FENG Zhiping +2 位作者 LI Nan CHEN Bingjian CHEN Xinjun 《Journal of Ocean University of China》 SCIE CAS CSCD 2022年第6期1669-1681,共13页
Abundance and distribution of jumbo flying squid(Dosidicus gigas)are evidently influenced by the changes of marine environment.In this study,the maximum entropy(MaxEnt)model was applied to examine the impacts of marin... Abundance and distribution of jumbo flying squid(Dosidicus gigas)are evidently influenced by the changes of marine environment.In this study,the maximum entropy(MaxEnt)model was applied to examine the impacts of marine environmental variables on its potential distribution,and identified habitat hotspots of D.gigas in summer and autumn along the coast of Chile.The MaxEnt model was constructed by using the fisheries data of D.gigas from summer to autumn during 2011–2017 combined with critical environmental factors including mixed layer depth(MLD),sea surface salinity(SSS),sea surface height(SSH)and water temperature at depths of 0 m,25 m,50 m,100 m,150 m,200 m,300 m,400 m and 500 m.Results showed that the actual fishing efforts of D.gigas in summer and autumn were mostly distributed in the suitable habitat,indicating that the MaxEnt model can well predict the habitat hotspots of D.gigas off Chile.The key environmental factors and their suitable ranges for D.gigas showed significant intermonthly changes from December to May.The critical environmental factors of D.gigas off Chile were MLD,SSH,water temperature at different depths in summer(Temp_25 m in December,Temp_300 m in January and Temp_400 m in February)and SSH,SSS,Temp_400 m in autumn.Our findings suggest that selecting the key environmental factors is vital to study the potential distribution of D.gigas off Chile in each month to explore its habitat hotspots. 展开更多
关键词 Dosidicus gigas MaxEnt model environmental effects habitat hotspots key environmental factors off Chile
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Introduction of Woody Landscape Plants in Linzhi City of Tibet
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作者 LIU Zhineng XING Zhen +1 位作者 YAO Xiazhen ZHOU Peng 《Journal of Landscape Research》 2016年第4期98-102,106,共6页
Due to the special geographical conditions of Tibet,the plant species applied in local landscaping have been limited.In the landscaping project of Fujian Park,59 woody landscape plant species were introduced from the ... Due to the special geographical conditions of Tibet,the plant species applied in local landscaping have been limited.In the landscaping project of Fujian Park,59 woody landscape plant species were introduced from the hinterland,and the survival rate and growth vigor of these species had been observed for 15 years.In terms of growth vigor and ornamental character,about 32 species showed good performance such as Prunus cerasifera f.atropuipurea and Dendrobenthemia japonica;8 species showed moderate growth performance such as Metasequoia glyptostroboides Hu et Cheng and Magnolia denudata Desr.;14 species showed poor growth vigor such as Ginkgo biloba L.and Osmanthus fragrans Lour.,and 5 species died such as Albizzia julibnssin Durazz.and Hibiscus mutabihs L..Moreover,the paper explored key factors that influence the introduction of woody landscape plants in Linzhi City and pointed out that wind damage and low temperature were 2 key factors. 展开更多
关键词 Woody landscape plants INTRODUCTION key factor Linzhi City TIBET
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Tourism will be a Key Factor in the Global Drive out of Recession and a Strong Contributor to a Long Term Green Economic New Deal
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《饭店现代化》 2009年第2期33-,共1页
Tourism is facing increasingly difficult conditions as the global economy deteriorates and Asia and the Pacific, one of fastest growing tourism regions in the world,is also strongly feeling the impact of the global sl... Tourism is facing increasingly difficult conditions as the global economy deteriorates and Asia and the Pacific, one of fastest growing tourism regions in the world,is also strongly feeling the impact of the global slowdown.But,as concluded by the over 100 experts from 25 countries gathered in Guilin for the 2nd UNWTO Conference on 展开更多
关键词 WILL over Tourism will be a key Factor in the Global Drive out of Recession and a Strong Contributor to a Long Term Green Economic New Deal Long
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Unconformity structures controlling stratigraphic reservoirs in the north-west margin of Junggar basin, North-west China 被引量:13
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作者 Kongyou WU Douglas PATON Ming ZHA 《Frontiers of Earth Science》 SCIE CAS CSCD 2013年第1期55-64,共10页
Tectonic movements formed several unconfor- mities in the north-west margin of the Junggar basin. Based on data of outcrop, core, and samples, the unconformity is a structural body whose formation associates with weat... Tectonic movements formed several unconfor- mities in the north-west margin of the Junggar basin. Based on data of outcrop, core, and samples, the unconformity is a structural body whose formation associates with weath- ering, leaching, and onlap. At the same time, the structural body may be divided into three layers, including upper layer, mid layer, and lower layer. The upper layer with good primary porosity serves as the hydrocarbon migration system, and also accumulates the hydrocarbon. The mid layer with compactness and ductility can play a role as cap rock, the strength of which increases with depth. The lower layer with good secondary porosity due to weathering and leaching can form the stratigraphic truncation traps. A typical stratigraphie reservoir lying in the unconformity between the Jurassic and Triassic in the north-west margin of the Junggar basin was meticulously analyzed in order to reveal the key controlling factors. The results showed that the hydrocarbon distribution in the stratigraphic onlap reservoirs was controlled by the onlap line, the hydro- carbon distribution in the stratigraphic truncation reser- voirs was confined by the truncation line, and the mid layer acted as the key sealing rock. So a conclusion was drawn that "two lines (onlap line and truncation line) and a body (unconformity structural body)" control the formation and distribution of stratigraphic reservoirs. 展开更多
关键词 unconformity structural body stratigraphicreservoir key controlling factors Jurassic bottom north-west margin of the Junggar basin
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The evolution of investments decision mode in China's telecommunication 被引量:2
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作者 ZHANG Ai-hua ZHAO Lian-qiang SHU Hua-ying 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 2007年第1期122-128,共7页
This essay analyzes the data of Chinese telecommunication market, telecommunication investments and investment benefits over the past 20 years. On the basis of these data, the essay reviews Chinese changing telecommun... This essay analyzes the data of Chinese telecommunication market, telecommunication investments and investment benefits over the past 20 years. On the basis of these data, the essay reviews Chinese changing telecommunication policies and discusses the major events in the course of China's telecommunication development. It is argued that telecommunication policies, regime backgrounds and market demand characteristics have a significant impact on investment decision mode in telecommunication industry. The evolution of network investments decision mode in China's telecommunication has corresponded to the transformation of these key factors. Considering the special events in the development of Chinese telecommunication as divisions, the essay discusses three stages of the evolution of investments decision mode in China's tel With the firm environment and problems that Chinese telecommunication operators have been facing since 2000 analyzed, it is demonstrated that Chinese telecommunication operators should change their mode of investment decision into the "profit-oriented investment decision mode" in order to achieve a high growth performance in the capital market,. This investment decision mode will result in increase of the investment profit with limited investment capital. The main procedure of profit-oriented investment decision mode is set out, which is abstracted to a mathematical model eventually. 展开更多
关键词 China's telecommunication investment decision mode evolution stage key factor investment profit
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Research Progress on Prevention and Treatment of Glucolipid Metabolic Disease with Integrated Traditional Chinese and Western Medicine 被引量:21
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作者 GUO Jiao 《Chinese Journal of Integrative Medicine》 SCIE CAS CSCD 2017年第6期403-409,共7页
Hyperlipidemia, type 2 diabetes mellitus, nonalcoholic fatty liver and many other metabolic disorder are frequently co-existing in patients. In addition, these diseases are closely related in pathophysiological settin... Hyperlipidemia, type 2 diabetes mellitus, nonalcoholic fatty liver and many other metabolic disorder are frequently co-existing in patients. In addition, these diseases are closely related in pathophysiological settings. However, increasing of the disease incidence, lacking of comprehensive prevention and control measurements against the key pathology point concomitant occurrence with the pattem of the single disease, single target therapy, that is leading therapeutic strategy for these metabolic disorders in the setting of Western medicine (WM). On the basis of the combination of the advantages of integrated Chinese medicine (CM) and WM, with unified understanding of such diseases, the new concept of glucolipid metabolic disease (GLMD) is introduced. In this new concept, disorders in glucose and lipid metabolism are recognized as the key trigger and major driving force for the progress of GLMD. The key points of pathology included dysfunction of neuronal-endocrine-immune system,insulin resistance, oxidative stress, inflammation and intestinal flora imbalance. In the core pathogenic perspective of CM, it can be explained as "Gan (Liver) Shi Shu Xie" (dysfunction of Gan in metabolism and emotion regulation) that will lead to the occurence/production of endogenous dampness and phlegm, blood stasis and turbid. This leads to the new concept of "Liver-based regulatory system for metabolic homeostasis" to be introduced further. The comprehensive prevention and control strategy "Tiao Gan Qi Shu Hua Zhuo" (modulating Gan, trigging key metabolic system to resolve pathogenic factors such as phlegm retention and dampness). Its representative formula Fufang Zhenzhu Tiaozhi Capsule (复方贞术调脂胶囊) is innovated under such rationales. Comment for some commonly-used CM GLMD therapeutic drugs was presented. High-level evidence-based and epidemiological and mechanism studies should be carded out to further interpret and explain of the scientific connotation of GLMD. 展开更多
关键词 glucolipid metabolic disease liver-based regulatory system for metabolic homeostasis Tiao Gan (Liver) Qi Shu Hua Zhuo (modulating Gan trigging key metabolic system to resolve pathogenic factors such as phlegm retention and dampness) Chinese medicine
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