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Allelopathic Effects of Water Extracts of Sweet Potato (Ipomoea batatas) on Seed Germination of Ageratum conyzoides 被引量:1
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作者 Shuangshuang Zhang Wenlei Cheng +2 位作者 Ye Chen Mingxing Jiang Genshen Yin 《Journal of Agricultural Chemistry and Environment》 CAS 2023年第2期124-133,共10页
Sustainable weed management strategies are essential to reduce chemical and labor inputs. This study aimed to evaluate the effect of water extracts from sweet potato [Ipomoea batatas (L.) Lamarck] on seed germination ... Sustainable weed management strategies are essential to reduce chemical and labor inputs. This study aimed to evaluate the effect of water extracts from sweet potato [Ipomoea batatas (L.) Lamarck] on seed germination of Ageratum conyzoides L. under controlled conditions. The aqueous was produced from plant parts i.e., roots, stems, and leaves of sweet potato at concentrations of 0.025, 0.050, 0.075, and 0.100 g·mL<sup>-1</sup>. The results showed that the plant parts of sweet potato all contained allelopathic substances, which showed high-concentration inhibition and low-concentration promotion of seed germination of A. conyzoides. When the aqueous extract concentrations were 0.050, 0.075, and 0.100 g·mL<sup>-1</sup>, the germination of A. conyzoides seeds was inhibited, while the germination was promoted at a concentration of 0.025 g·mL<sup>-1</sup>. This shows that when the planting density of sweet potato is large, it can form an obvious prevention and control effect on A. conyzoides, and thus improve herbicide resistance management. 展开更多
关键词 Sweet Potato geratum conyzoides water extracts Allelopathic Effect
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Antibacterial Effects of Water Extracts of Various Broadleaf Wild Leeks (Allium ampeloprasum)
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作者 Armin Tavakkoli Barat Oboud Alireza Tavakkoli 《Journal of Pharmacy and Pharmacology》 2015年第9期438-442,共5页
There are numerous reports regarding the antimicrobial effects of herbal extracts on bacteria and fungi. We have prepared water extracts of Wild Leek (A. ampeloprasum var. porrum), Kurrat (A. ampeloprasum var. kur... There are numerous reports regarding the antimicrobial effects of herbal extracts on bacteria and fungi. We have prepared water extracts of Wild Leek (A. ampeloprasum var. porrum), Kurrat (A. ampeloprasum var. kurrat) and Elephant Garlic (A. ampeloprasum var. ampeloprasum) by rotary vacuum distillation. As a result, the extraction was carried out in 40 ℃ thus omitting any risk of loss of anti-bacterial activity due to high temperatures reported in prior similar studies [ 1]. The five bacteria Bacillus subtilis, Pseudomonas aeruginosa, Escherichia coli, Enterococcus faecalis, and Staphylococcus aureus were tested against the extracts. While some extent of inhibition was observed when the bacteria were cultured in presence of the leek and kurrat extracts, elephant garlic was determined to possess an extreme inhibitory quality against all the aforementioned bacteria, completely inhibiting the growth of the bacteria after 24 hrs of culture in exposure to the extract. We propose that elephant garlic extract could be an effective alternative to chemical antibiotic treatments and disinfectants in hospital and other settings in which infections are common. 展开更多
关键词 Elephant garlic kurrat LEEK Bacillus subtilis Pseudomonas aeruginosa Escherichia coli Staphylococcus aureus Enterococcus faecalis water extracts inhibition.
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Effect of water extracts of larch on growth of Manchurian walnut seedlings 被引量:9
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作者 YANG Li-xue 《Journal of Forestry Research》 SCIE CAS CSCD 2005年第4期285-288,共4页
A study was conducted to detect the effect of water extracts from different parts such as root, bark, branch and leaf, of adult larch, Larix gmelini, trees on growth of Manchurian walnut, Juglans mandshudca, seedlings... A study was conducted to detect the effect of water extracts from different parts such as root, bark, branch and leaf, of adult larch, Larix gmelini, trees on growth of Manchurian walnut, Juglans mandshudca, seedlings and the allelopathy between the two tree species. Four concentrations (100 g. kg i, 50 g. kg^-1, 25 g. kg^-1 and 12.5 g. kg^-1) were prepared for each kind of extracts. Result showed that the water extracts with low and moderate concentrations accelerated the growth of collar diameter and increased biomass and root/shoot ratio of walnut seedlings. The water extracts from branches and barks with low and moderate concentrations accelerated the height growth of the seedlings, while those from leaves and roots slightly decreased the height growth of seedlings. The fact that application of water extracts of larch improved the growth of Manchurian walnut attributes possibly to the allelopathy between the two tree species. 展开更多
关键词 Juglans mandshurica Larix gmelini water extract Collar diameter Tree height Root/shoot ratio ALLELOPATHY
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Anti-tumor Effect and Protective Effect on Chemotherapeutic Damage of Water Soluble Extracts from Hedyotis diffusa 被引量:26
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作者 李瑞 赵浩如 林以宁 《Journal of Chinese Pharmaceutical Sciences》 CAS 2002年第2期54-58,共5页
Bai-Hua-She-She-Cao Hedyotis diffusa Willd. (Ru-biaceae) is a medicinal herbwidely distributed in northeast Asian countries. In traditional Chinese medicine, it has the effectof 'clearing away heat and toxic mater... Bai-Hua-She-She-Cao Hedyotis diffusa Willd. (Ru-biaceae) is a medicinal herbwidely distributed in northeast Asian countries. In traditional Chinese medicine, it has the effectof 'clearing away heat and toxic material, promoting blood circulation and removing blood stasis'.It is a well known Chinese folk-medicine used for the treatment of appendicitis, sore throat, mumps,acne, sebo-rheic dermatitis and various kinds of tumors, such as tumors of digestive tract,carcinoma of liver. It was reported that the MeOH extract of H. diffusa demonstrated a significantantitumor activity and ursolic acid succeeded in being isolated from the MeOH extract as an activecomponent . Shan BN, et al suggested that the direct aqueous extract of H. diffusa hadimmuno-modulating activity and antitumor activity in vitro through stimulating the immune system tokill or engulf tumor cells. But regarding anti-tumor activity in vivo of water soluble extracts fromH. diffusa, no detail was reported. Therefore, we prepared water soluble extracts (H_1 and H_2)from H. diffusa and evaluated their anti-tumor property in vivo experiments as well as protectiveeffect on chemo-therapeutic damage. 展开更多
关键词 hedyotis diffusa water soluble extracts ANTI-TUMOR CHEMOTHERAPY
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Mutagenicity and Genotoxicity of Organic Extracts from Finished Water with Different Treatment Process
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作者 FANG Dao Kui ZHOU Guo Hong +1 位作者 YU Shu Yuan FENG Jin Shu 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2018年第8期632-636,共5页
Purification of surface water is widely practiced with conventional water treatment processes like coagulation-flocculation, sedimentation, filtration,and disinfection. Some reports have specified that conventional wa... Purification of surface water is widely practiced with conventional water treatment processes like coagulation-flocculation, sedimentation, filtration,and disinfection. Some reports have specified that conventional wastewater purification processes do not effectively remove many chemical contaminants, 展开更多
关键词 Mutagenicity and Genotoxicity of Organic extracts from Finished water with Different Treatment Process
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Fractionation of water-soluble organic matter(WSOM)with polyvinylpyrrolidone:A study on antimony associated with WSOM in contaminated soils
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作者 Saeed Bagherifam Trevor C.Brown +2 位作者 Andrea Baglieri Binoy Sarkar Jörg Rinklebe 《Journal of Environmental Sciences》 2025年第11期303-313,共11页
Water-soluble organic matter(WSOM)significantly influences the transport of metals and organic contaminants in soils,yet the interaction specifics with antimony(Sb)remain largely unexplored.Antimony is of particular e... Water-soluble organic matter(WSOM)significantly influences the transport of metals and organic contaminants in soils,yet the interaction specifics with antimony(Sb)remain largely unexplored.Antimony is of particular environmental concern due to its toxic properties and harmful effects on ecosystems and human health.Employing a three-step fractionation method with polyvinylpyrrolidone(PVP),this study aimed to isolate and analyze humic acids(HA),PVP-non adsorbed fulvic acids(FAA),and PVP-adsorbed fulvic acids(FAB)from WSOM in soil spiked with Sb and incubated for 18 months.These fractions underwent chemical analysis for carbon(C),nitrogen(N),total organic carbon(TOC),and Sb,complemented by FTIR and 1H NMR spectroscopic characterization.The study revealed that HA wasmore aliphatic,with Sb predominantly associating with the fulvic acid(FA)fraction,accounting for 97%of Sb in extracts.Specifically,the FAA subfraction held substantial portions of total carbon(TC),total nitrogen(TN),total organic carbon(TOC),and Sb.Correlations between Sb concentrations and TN,TC,and TOC were significant.Extraction methods showed NaOH and Na_(4)P_(2)O_(7) outperformed HCl and deionised water in extracting TC,TN,and TOC,with higher Sb concentrations found in Na_(4)P_(2)O_(7) and NaOH extracts.This underscores the role of Fe/Al-SOM complexes in Sb soil availability.The results revealed that FAA subfraction accounted for 76%,64%and 94%of TN,TOC and Sb,respectively.Therefore,this research highlights the FAA fraction’s central role,predominantly comprising non-humic substances like amines,in the availability of C,N,and Sb in Sb-impacted soils.The findings offer insights for environmental management and remediation strategies. 展开更多
关键词 POLYVINYLPYRROLIDONE water extractable organic matter Sodium pyrophosphate ANTIMONY Iron Dissolved organic carbon Fulvic acids FRACTIONATION
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Regulatory Effects of Radix Salviae Miltiorrhizae Water Extract and Semen Ziziphi Spinosae Compound onβ-secretase Activity in Mice Exposed to Aluminum Maltolate
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作者 Jiaguo LIANG Min WEI +7 位作者 Yuxue HUANG Yu GU Jinmiao WU Kun CHEN Yongqiu QIU Yuncong LU Junchen WEI Shuqiu ZHANG 《Medicinal Plant》 2025年第4期39-42,共4页
[Objectives]To explore the effects of Radix Salviae Miltiorrhizae water extract and Semen Ziziphi Spinosae compound on theβ-secretase activity in mice exposed to aluminum maltolate.[Methods]A total of 60 healthy,clea... [Objectives]To explore the effects of Radix Salviae Miltiorrhizae water extract and Semen Ziziphi Spinosae compound on theβ-secretase activity in mice exposed to aluminum maltolate.[Methods]A total of 60 healthy,clean-grade SPF mice were randomly assigned to four groups based on their body weight,with each group consisting of 15 mice.The groups included a control group,a model group,treatment group 1,and treatment group 2.The control group received an equivalent dose of normal saline,while the model group and treatment groups 1 and 2 were intraperitoneally injected with 0.3 mg/kg of aluminum maltolate solution for 60 d.Additionally,treatment groups 1 and 2 were injected with 0.3 mg/kg of Radix Salviae Miltiorrhizae water extract and 0.3 mg/kg of Semen Ziziphi Spinosae compound,respectively,starting from the 31 st day for a total of 30 d.The cognitive functions of mice,specifically their learning and memory capabilities,were assessed using the Y-shaped water maze test at three distinct time points:prior to,during,and following the experimental procedure.Serum samples were collected for the analysis of various biochemical markers,including hemoglobin(Hb),total cholesterol(TC),triglycerides(TG),total protein(TP),alanine aminotransferase(ALT),and blood urea nitrogen(BUN).Additionally,brain tissues were harvested to evaluate the levels of glutathione peroxidase(GSH-PX)and acetylcholinesterase(AChE)in both serum and brain samples.The expression levels ofα-secretase,β-secretase,andγ-secretase in mouse serum were quantified using enzyme-linked immunosorbent assay(ELISA).[Results]According to the final results of the Y-shaped water maze test,the administration of therapeutic drugs to mice resulted in a gradual reduction in both the swimming time and the distance traveled to reach the platform in treatment groups 1 and 2.Additionally,the number of errors made by these treatment groups was significantly greater than that observed in the control group,with statistically significant differences(P<0.01).Among the three groups subjected to subchronic aluminum exposure,statistically significant differences were observed in the levels of Hb,TC,TG,TP,ALT,BUN,brain GSH-PX,and brain AChE(P<0.05).Furthermore,with the increasing duration of therapeutic drug administration,the levels ofβ-secretase in the brains of mice in both the treatment groups and the model group exhibited a significant decrease,while the levels ofα-secretase showed a significant increase.Additionally,the differences were statistically significant when compared to the control group(P<0.05).[Conclusions]Radix Salviae Miltiorrhizae water extract and Semen Ziziphi Spinosae compound will decrease the expression level ofβ-secretase activity in mice exposed to aluminum maltolate. 展开更多
关键词 Radix Salviae Miltiorrhizae water extract Semen Ziziphi Spinosae compound ALUMINUM Β-SECRETASE MICE Learning and memory capability
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Study on Processing of Clear Banana Juice Using Hot Water Extraction Method 被引量:2
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作者 郑欣 余元善 +4 位作者 吴继军 徐玉娟 肖更生 黄婉华 温靖 《Agricultural Science & Technology》 CAS 2014年第11期2003-2005,2044,共4页
In this study, the effects of hot water temperature on clarity, total soluble solids, polyphenol oxidase (PPO) and color of banana juice during hot water ex-traction were discussed based on the theory in which heat ... In this study, the effects of hot water temperature on clarity, total soluble solids, polyphenol oxidase (PPO) and color of banana juice during hot water ex-traction were discussed based on the theory in which heat treatment might induce the pectin and protein in banana pulp to form insoluble products. The results showed the hot water temperature had a significant effect on the formation of insol-uble polymers in banana pulp from pectin and protein. In 75 ℃ water, the pectin and protein in banana pulp were most inclined to form insoluble products. Under this condition, the clarity of banana juice was also highest. The light transmittance at 660 nm was close to 90%. In the banana juice, extracted by 75 ℃ water, the pectin and protein contents were lowest, and they were lower than 7.3 mg/100 ml and 12.9 mg/100 ml respectively. The 75 ℃ water could not inactivate completely the pectin in banana pulp due to its high heat resistance, Therefore, 0.05% L-cys-teine or ascorbic acid needed to be added into banana pulp to inhibit the browning of juice induced by residual PPO. 展开更多
关键词 Clear banana juice Hot water extraction Polyphenol oxidase Pectin Protein
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Toxicity Effects of Water Extract of Euphorbia fischeriana Steud.against Silkworm(Bombyx mori)
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作者 侯伟倬 甄占萱 +3 位作者 李云祥 杨贵明 李季生 李娜 《Plant Diseases and Pests》 CAS 2011年第1期64-66,共3页
[Objective] Taking silkworm (Bombyx mori) as the test material, the research aimed to study the toxicity effects of Euphorbiafischeriana Steud. against the insects in Lepidoptera. [ Methods ] Water extract was prepa... [Objective] Taking silkworm (Bombyx mori) as the test material, the research aimed to study the toxicity effects of Euphorbiafischeriana Steud. against the insects in Lepidoptera. [ Methods ] Water extract was prepared with fresh perennial E. fischer/ana Steud. , which was applied in silkworm with different methods including daubing the extract on silkworm back, soaking silkworm in the extract and feeding silkworm with the mulberry leaves daubed by the extract. [ Re- suits] Those silkworms whose backs were daubed with the water extract had no obvious poisoning symptom. The silkworms soaked for 1 and 3 min could be survived for about 7 d; the silkworms soaked for 5 min could be survived for about 2 d; and the silkworms soaked for 15 rain could be survived for 10 h at most. Those silk- worms fed with mulberry leaves daubed by water extract completely died after 2 d. [ Conduslons ] The water extract of E. fischer/ana Steud. had significant contact toxicity and stomach poisoning against silkworm. 展开更多
关键词 Euphorbiafischeriana Steud. water extract SILKWORM Contact toxicity Stomach poisoning
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Proposed Models for Subcritical Water Extraction of Essential Oils 被引量:9
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作者 M.Khajenoori A.Haghighi Asl F.Hormozi 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2009年第3期359-365,共7页
Mechanisms that control the extraction rate of essential oil from Zataria multiflora Boiss. (Z. multiflora) with subcritical water (SW) were studied. The extraction curves at different solvent flow rates were used to ... Mechanisms that control the extraction rate of essential oil from Zataria multiflora Boiss. (Z. multiflora) with subcritical water (SW) were studied. The extraction curves at different solvent flow rates were used to deter-mine whether the extractions were limited primarily by the near equilibrium partitioning of the analyte between the matrix and solvent (i.e. partitioning thermodynamics) or by the rates of analyte desorption from the matrix (i.e. ki-netics). Four simple models have been applied to describe the extraction profiles obtained with SW: (1) a model based solely on the thermodynamic distribution coefficient KD, which assumes that analyte desorption from the ma-trix is rapid compared to elution; (2) one-site kinetic model, which assumes that the extraction rate is limited by the analyte desorption rate from the matrix, and is not limited by the thermodynamic (KD) partitioning that occurs dur-ing elution; (3) two-site kinetic model and (4) external mass transfer resistance model. For SW extraction, the thermodynamic elution of analytes from the matrix was the prevailing mechanism as evidenced by the fact that ex-traction rates increased proportionally with the SW flow rate. This was also confirmed by the fact that simple re-moval calculations based on determined KD (for major essential oil compounds) gave good fits to experimental data for flow rates from 1 to 4 ml·min-1. The results suggested that the overall extraction mechanism was influenced by solute partitioning equilibrium with external mass transfer through liquid film. 展开更多
关键词 essential oils Zataria multiflora Boiss. subcrltlcal water extraction mechanisn
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Effect of Temperature, pH and Salt on Fluorescent Quality of Water Extractable Organic Matter in Black Soil 被引量:9
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作者 LI Ming-tang ZHAO Lan-po ZHANG Jin-jing 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2013年第7期1251-1257,共7页
Water erosion is the major reason for the loss of soil organic carbon in the Northeast China, which leads to the soil quality deterioration and adjacent water pollution. In this study, the effect of extraction tempera... Water erosion is the major reason for the loss of soil organic carbon in the Northeast China, which leads to the soil quality deterioration and adjacent water pollution. In this study, the effect of extraction temperature, pH value, and salt on the water extractable organic matter (WEOM) was determined by means of the UV absorbance, fluorescence excitation-emission matrix, and derived fluorescence indexes. In general, the carbon content and aromaticity of WEOM increased with the increasing of extraction temperature, with the exception that there was no significant difference in the amount at 0 and 20℃. More fluorophores, especially microbially-derived organic matter were extracted at high temperature. The pH values of extractant, including 5, 7, and 10, showed no effect on the carbon amount of WEOM, whereas the aromaticity and microbially-derived component gradually increased with the increasing of pH values. The fluorescence intensity of humic acid-like fluorophore was stronger in neutral and alkali condition than that in acidic condition. The addition of 10 mmol L-1 CaCl2 significantly decreased the carbon amount of recovered WEOM. Moreover, it significantly decreased the aromaticity of WEOM and the quantity of fulvic acid-like and humic acid-like fluorophores, whereas increased the percentage of tyrosine-like and tryptophan-like fluorophores in the total fluorophores and the amount of microbially-derived organic matter. Generally, 10 mmol L-1 KCl showed the same influence trend, but with low influence degree. 展开更多
关键词 black soil water extractable organic matter soil profile fluorescence spectroscopy
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Biodegradability of soil water soluble organic carbon extracted from seven different soils 被引量:8
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作者 SCAGLIA Barbara ADANI Fabrizio 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第5期641-646,共6页
Water soluble organic carbon (WSOC) is considered the most mobile and reactive soil carbon source and its characterization is an important issue for soil ecology study. A biodegradability test was set up to study WS... Water soluble organic carbon (WSOC) is considered the most mobile and reactive soil carbon source and its characterization is an important issue for soil ecology study. A biodegradability test was set up to study WSOC extracted from 7 soils differently managed. WSOC was extracted from soil with water (soil/water ratio of 1:2, W/V) for 30 min, and then tested for biodegradability by a liquid state respirometric test. Result obtained confirmed the finding that WSOC biodegradability depended on the both land use and management practice. These results suggested the biodegradability test as suitable method to characterize WSOC, and provided useful information to soil fertility. 展开更多
关键词 biodegradability test cumulated oxygen uptake water extractable organic carbon water soluble organic carbon
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Water extraction kinetics of metals, arsenic and dissolved organic carbon from industrial contaminated poplar leaves 被引量:4
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作者 Muhammad Shahid Tiantian Xiong +2 位作者 Maryse Castrec-Rouelle Tibo Leveque Camille Dumat 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2013年第12期2451-2459,共9页
In industrial areas, tree leaves contaminated by metals and metalloids could constitute a secondary source of pollutants. In the present study, water extraction kinetics of inorganic elements (IE: Pb, Zn, Cd, As, Fe... In industrial areas, tree leaves contaminated by metals and metalloids could constitute a secondary source of pollutants. In the present study, water extraction kinetics of inorganic elements (IE: Pb, Zn, Cd, As, Fe and Mn), dissolved organic carbon, pH and biological activity were studied for industrial contaminated poplar leaves. Moreover, the distribution of the IE through the size fractions of the associated top soil was measured. High quantities ofMn, Zn and As and polysaccharides were released in the solution from the strongly contaminated leaves. The kinetic of release varied with time and metal type. The solution pH decreased while dissolved organic contents increased with time after 30 days. Therefore, these contaminated leaves could constitute a source of more available organic metals and metalloids than the initial inorganic process particles. However, the distribution of the IE through the size fractions of the top soil suggested that a great part of the released IE was adsorbed, reducing in consequence their transfers and bioavailability. It's concluded that mobility/boioavailability and speciation of metals and metalloids released from the decomposition of polluted tree leaves depends on soil characteristics, pollutant type and litter composition, with consequences for environmental risk assessment. 展开更多
关键词 metals and metalloids dissolved organic carbon litter decomposition kinetics SPECIATION water extraction
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Screening the effective components in treating dampness stagnancy due to spleen deficiency syndrome and elucidating the potential mechanism of Poria water extract 被引量:3
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作者 LI Huijun ZHANG Dandan +9 位作者 WANG Tianhe LUO Xinyao XIA Heyuan PAN Xiang HAN Sijie YOU Pengtao WEI Qiong LIU Dan ZOU Zhongmei YE Xiaochuan 《Chinese Journal of Natural Medicines》 SCIE CAS CSCD 2023年第2期83-98,共16页
Poria is an important medicine for inducing diuresis to drain dampness from the middle energizer.However,the specific effective components and the potential mechanism of Poria remain largely unknown.To identify the ef... Poria is an important medicine for inducing diuresis to drain dampness from the middle energizer.However,the specific effective components and the potential mechanism of Poria remain largely unknown.To identify the effective components and the mechanism of Poria water extract(PWE)to treat dampness stagnancy due to spleen deficiency syndrome(DSSD),a rat model of DSSD was established through weight-loaded forced swimming,intragastric ice-water stimulation,humid living environment,and alternate-day fasting for 21 days.After 14 days of treatment with PWE,the results indicated that PWE increased fecal moisture percentage,urine output,D-xylose level and weight;amylase,albumin,and total protein levels;and the swimming time of rats with DSSD to different extents.Eleven highly related components were screened out using the spectrum-effect relationship and LC-MS.Mechanistic studies revealed that PWE significantly increased the expression of serum motilin(MTL),gastrin(GAS),ADCY5/6,p-PKAα/β/γcat,and phosphorylated cAMP-response element binding protein in the stomach,and AQP3 expression in the colon.Moreover,it decreased the levels of serum ADH,the expression of AQP3 and AQP4 in the stomach,AQP1 and AQP3 in the duodenum,and AQP4 in the colon.PWE induced diuresis to drain dampness in rats with DSSD.Eleven main effective components were identified in PWE.They exerted therapeutic effect by regulating the AC-cAMP-AQP signaling pathway in the stomach,MTL and GAS levels in the serum,AQP1 and AQP3 expression in the duodenum,and AQP3 and AQP4 expression in the colon. 展开更多
关键词 Poria water extract Dampness stagnancy due to spleen deficiency syndrome Spectrum-effect relationship Effective components MECHANISMS
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Comparison of surface water extraction performances of different classic water indices using OLI and TM imageries in different situations 被引量:2
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作者 Ke ZHAI Xiaoqing WU +1 位作者 Yuanwei QIN Peipei DU 《Geo-Spatial Information Science》 SCIE EI CSCD 2015年第1期32-42,共11页
Recently,water extraction based on the indices method has been documented in many studies using various remote sensing data sources.Among them,Landsat satellites data have certain advantages in spatial resolution and ... Recently,water extraction based on the indices method has been documented in many studies using various remote sensing data sources.Among them,Landsat satellites data have certain advantages in spatial resolution and cost.After the successful launch of Landsat 8,the Operational Land Imager(OLI)data from the satellite are getting more and more attention because of its new improvements.In this study,we used the OLI imagery data source to study the water extraction performance based on the Normalized Difference Vegetation Index,Normalized Difference Water Index,Modified Normalized Water Index(MNDWI),and Automated Water Extraction Index(AWEI)and compared the results with the Thematic Mapper(TM)imagery data.Two test sites in Tianjin City of north China were selected as the study area to verify the applicability of OLI data and demonstrate its advantages over TM data.We found that the results of surface water extraction based on OLI data are slightly better than that based on TM in the two test sites,especially in the city site.The AWEI and MNDWI indices performs better than the other two indices,and the thresholds of water indices show more stability when using the OLI data.So,it is suitable to combine OLI imagery with other Landsat sensor data to study water changes for long periods of time. 展开更多
关键词 water extraction operational land imager(OLI)data threshold stability water indices
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Automated Extraction for Water Bodies Using New Water Index from Landsat 8 OLI Images 被引量:5
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作者 Pu YAN Yue FANG +2 位作者 Jie CHEN Gang WANG Qingwei TANG 《Journal of Geodesy and Geoinformation Science》 CSCD 2023年第1期59-75,共17页
The extraction of water bodies is essential for monitoring water resources,ecosystem services and the hydrological cycle,so analyzing water bodies from remote sensing images is necessary.The water index is designed to... The extraction of water bodies is essential for monitoring water resources,ecosystem services and the hydrological cycle,so analyzing water bodies from remote sensing images is necessary.The water index is designed to highlight water bodies in remote sensing images.We employ a new water index and digital image processing technology to extract water bodies automatically and accurately from Landsat 8 OLI images.Firstly,we preprocess Landsat 8 OLI images with radiometric calibration and atmospheric correction.Subsequently,we apply KT transformation,LBV transformation,AWEI nsh,and HIS transformation to the preprocessed image to calculate a new water index.Then,we perform linear feature enhancement and improve the local adaptive threshold segmentation method to extract small water bodies accurately.Meanwhile,we employ morphological enhancement and improve the local adaptive threshold segmentation method to extract large water bodies.Finally,we combine small and large water bodies to get complete water bodies.Compared with other traditional methods,our method has apparent advantages in water extraction,particularly in the extraction of small water bodies. 展开更多
关键词 water bodies extraction Landsat 8 OLI images water index improved local adaptive threshold segmentation linear feature enhancement
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Inhibitory Effects of Polygoni Multiflori Caulis Extracts on Matrix Metalloproteinase Activities 被引量:2
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作者 LIU Jun-song YANG Jin-gang +4 位作者 HONG Yuan JIN Feng-hai WANG Ming-cui ZHAO Shu-hua FANG Xue-xun 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2009年第2期211-215,共5页
Matrix metalloproteinases(MMPs) play an essential role in development and tissue remodeling of living organisms. However, the overexpression of MMPs has lead to a series of diseases, such as cancer, arthritis, and a... Matrix metalloproteinases(MMPs) play an essential role in development and tissue remodeling of living organisms. However, the overexpression of MMPs has lead to a series of diseases, such as cancer, arthritis, and atherosclerosis; and inhibition of MMPs may have therapeutic benefits. The discovery of MMP inhibitors from herbal has become a prospective event. We showed that the extract of Polygoni multiflori caulis from ethyl acetate or water(ethyl acetate extract and water extract) can inhibit the activities of MMPs 9, 14, and 16 in a dose-dependent manner and n-butyl alcohol extract of it can also inhibit these MMPs. Furthermore, we found that n-butyl alcohol extract and water extract of it influence the cell viability. These discoveries may contribute to the development of MMP in- hibitors for the therapy of a variety of pathological conditions. 展开更多
关键词 Matrix metalloproteinases(MMPs) Polygoni multi/lori caulis water extract Cell viability assay
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Inhibitory Effects of Ginseng Water Extract on Hydroxyl Radical 被引量:3
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作者 Hongyan LI Ruihai LI +1 位作者 Lin ZHAO Yang CAO 《Medicinal Plant》 CAS 2018年第4期107-109,118,共4页
[Objectives] The aim of this work was to compare the inhibitory effects of different water-soluble extracts of ginseng on hydroxyl radical. [Methods]The water-soluble effective parts of ginseng were extracted by ortho... [Objectives] The aim of this work was to compare the inhibitory effects of different water-soluble extracts of ginseng on hydroxyl radical. [Methods]The water-soluble effective parts of ginseng were extracted by orthogonal test,the hydroxyl radical scavenging rate of each extract was determined by salicylic acid method,and the extraction process of the optimum hydroxyl radical inhibitor was optimized using variance analysis and cluster analysis. [Results] A total of 16 samples were prepared. Among them,the sample No. 12 had the highest hydroxyl radical scavenging rate,and the inhibition rate reached 105. 08% at the concentration of 1 g/L. [Conclusions] Ginseng water extract contained hydroxyl radical scavenger,of which the optimum extraction process was as follows: p H of 8,solid to liquid ratio of 1∶ 10,extraction temperature of 4℃,extraction time of 12 h and extraction times of 3. 展开更多
关键词 Ginseng water extract Orthogonal text Hydroxyl radical ANTIOXIDATION
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SAR image water extraction using the attention U-net and multi-scale level set method:flood monitoring in South China in 2020 as a test case 被引量:1
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作者 Chuan Xu Shanshan Zhang +4 位作者 Bofei Zhao Chang Liu Haigang Sui Wei Yang Liye Mei 《Geo-Spatial Information Science》 SCIE EI CSCD 2022年第2期155-168,共14页
Level set method has been extensively used for image segmentation,which is a key technology of water extraction.However,one of the problems of the level-set method is how to find the appropriate initial surface parame... Level set method has been extensively used for image segmentation,which is a key technology of water extraction.However,one of the problems of the level-set method is how to find the appropriate initial surface parameters,which will affect the accuracy and speed of level set evolution.Recently,the semantic segmentation based on deep learning has opened the exciting research possibilities.In addition,the Convolutional Neural Network(CNN)has shown a strong feature representation capability.Therefore,in this paper,the CNN method is used to obtain the initial SAR image segmentation map to provide deep a priori information for the zero-level set curve,which only needs to describe the general outline of the water body,rather than the accurate edges.Compared with the traditional circular and rectangular zero-level set initialization method,this method can converge to the edge of the water body faster and more precisely;it will not fall into the local minimum value and be able to obtain accurate segmentation results.The effectiveness of the proposed method is demonstrated by the experimental results of flood disaster monitoring in South China in 2020. 展开更多
关键词 water extraction flood monitoring level set attention U-net Convolutional Neural Network(CNN)
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Extracting water body data based on SDWI and threshold segmentation:A case study in permafrost area surrounding Salt Lake in Hoh Xil,Qinghai-Tibet Plateau,China 被引量:2
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作者 QingSong Du GuoYu Li +4 位作者 Dun Chen ShunShun Qi Yu Zhou Fei Wang YaPeng Cao 《Research in Cold and Arid Regions》 CSCD 2023年第4期202-209,共8页
There are a large number of lakes,rivers,and other natural water bodies distributed in the permafrost area of the Qinghai-Tibet Plateau(QTP).The changes in water bodies will affect the distribution of water resources ... There are a large number of lakes,rivers,and other natural water bodies distributed in the permafrost area of the Qinghai-Tibet Plateau(QTP).The changes in water bodies will affect the distribution of water resources in sur-rounding areas and downstream areas,resulting in environmental impact and bringing potential flood disasters,which will induce more serious issues and problems in alpine and high-altitude areas with a fragile habitat(such as the QTP in China).Generally,effective,reasonable,and scientific monitoring of large-scale water bodies can not only document the changes in water bodies intuitively,but also provide important theoretical reference for subsequent environmental impact prediction,and disaster prevention and mitigation in due course of time.The large-scale water extraction technology derived from the optical remote sensing(RS)image is seriously affected by clouds,bringing about large differences among the extracted water result products.Synthetic aperture radar(SAR)RS technology has the unique advantage characteristics of all-weather,all-day,strong penetration,and not being affected by clouds,which is hopeful in extracting water body data,especially for days with cloudy weather.The data extraction of large-scale water bodies based on SAR images can effectively avoid the errors caused by clouds that become prevalent at present.In this paper,the Hoh Xil Salt Lake on the QTP and its surrounding five lakes are taken as the research objects.The 2-scene Sentinel-1 SAR image data covering the whole area on 22 August 2022 was used to verify the feasibility of extracting water body data in permafrost zones.Furthermore,on 22 August 2022,the wealth here was cloudy,which made the optical RS images,e.g.,Sentinel-2 images full of clouds.The results show that:using the Sentinel-1 image and threshold segmentation method to extract water body data is efficient and effective with excellent results in permafrost areas.Concretely,the Sentinel-1 dual-polarized water index(SDWI),calculated by combining dual vertical–vertical(VV)polarized and verti-cal–horizontal(VH)polarized data is a useful index for water extraction and the result is better than each of the VV or VH polarized images. 展开更多
关键词 Permafrost region water body extraction Salt Lake in Hoh Xil Qinghai-Tibet Plateau Sentinel-1 Ecological environment impact Disaster prevention and mitigation
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