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Pharmacokinetica studies of aristolochic acid-I and-II in rats after intragastrical administration of Radix Aristolochiae and Muskone 被引量:3
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作者 白玛卓玛 杨东辉 +2 位作者 俞捷 王璇 蔡少青 《Journal of Chinese Pharmaceutical Sciences》 CAS 2009年第1期79-83,共5页
The pharmacokinetic parameters of aristolochic acid-Ⅰ (AA-Ⅰ) and -Ⅱ (AA-Ⅱ) in rat serum after intragastrical administration of the crude drug powders of Radix Aristolochiae (RA) and Muskone containing equal ... The pharmacokinetic parameters of aristolochic acid-Ⅰ (AA-Ⅰ) and -Ⅱ (AA-Ⅱ) in rat serum after intragastrical administration of the crude drug powders of Radix Aristolochiae (RA) and Muskone containing equal amounts of RA were compared. The pharmacokinetic profiles of AA-Ⅰ and AA-Ⅱ could be fitted with a two-compartment model The elimination half time (T1/2β) of AA-Ⅰ in Muskone was 1573.2 min and that of AA-Ⅰ in RA was 475.8 min; T1/2β of AA-Ⅱ in Muskone was 2344.8 min and that of AA-Ⅱ in RA was 427.8 rain. The area under the concentration-time curve (AUC) of AA-Ⅰ in Muskone was 13.07 μg/h/mL and that of AA-Ⅰ in RA was 3.86 μg/h/mL; AUC of AA-Ⅱ in Muskone was 67.67 μg/h/mL and that of AA-Ⅱ in RA was 23.93 μg/h/mL. The bioavailabilities of AA-Ⅰ and AA-Ⅱ in Muskone were markedly increased compared with that in RA based on the elimination half-time and A UC values. 展开更多
关键词 Aristolochiae Radix Muskone Aristolochic acid- Aristolochic acid- PHARMACOKINETICS
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Comparison between Sulfuric Acid-phenol and Sulfuric Acid-anthrone Methods Used for Determination of Polysaccharides in Shoots of Aralia elata (Miq.) Seem. 被引量:3
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作者 Donghai CHU Zhanbo HUANG Fengwei HE 《Agricultural Biotechnology》 CAS 2018年第3期170-173,共4页
Sulfuric acid-phenol and sulfuric acid-anthrone methods were used to detect polysaccharide content in shoots of Aralia elata( Miq.) Seem.,and the conversion factor to glucose was measured with refined polysaccharide... Sulfuric acid-phenol and sulfuric acid-anthrone methods were used to detect polysaccharide content in shoots of Aralia elata( Miq.) Seem.,and the conversion factor to glucose was measured with refined polysaccharides. Comprehensive evaluation was carried out by linear relationship,precision,reproducibility,stability and recovery rate. The results showed that the linear relationship between glucose concentration and absorbance was good when glucose concentration was0-40 μg/ml,and the average recovery rate was equal to or higher than 97. 00% with good reproducibility( RSD 〈 1. 60%,n = 5). It revealed that the two methods were accurate and reliable,and suitable for the determination of polysaccharide content in the shoots of A. elata. Polysaccharide content detected by sulfuric acid-phenol and sulfuric acid-anthrone methods was 19. 31% and 20. 40% respectively. 展开更多
关键词 Shoots of Aralia elata (Miq.) Seem. POLYSACCHARIDES Sulfuric acid-phenol method Sulfuric acid-anthrone method
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Three component reactions: An efficient and green synthesis of 3, 4-dihydropyrimidin-2-(1H)-ones and thiones using silica gel-supported L-pyrrolidine-2-carboxylic acid-4-hydrogen sulfate 被引量:3
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作者 Arash Ghorbani-Choghamarani Parisa Zamani 《Chinese Chemical Letters》 SCIE CAS CSCD 2013年第9期804-808,共5页
An environmentally benign aqueous protocol for the synthesis of 3,4-dihydropyrimidin-2-( 1 H)-ones and thiones promoted by a green catalyst, silica gel-supported L-pyrrolidine-2-carboxylic acid-4-hydrogen sulfate, h... An environmentally benign aqueous protocol for the synthesis of 3,4-dihydropyrimidin-2-( 1 H)-ones and thiones promoted by a green catalyst, silica gel-supported L-pyrrolidine-2-carboxylic acid-4-hydrogen sulfate, has been developed. The use of nontoxic, thermally stable and inexpensive amino acid catalyst makes the process simple with minimal amount of chemical waste. Compared with classical Biginelli reaction conditions, this new method has the advantages of high yields and simple workup procedures. 展开更多
关键词 3 4-Dihya ropyrimldin-2 -( 1H)-ones(DHPMs)L-Pyrrolidine-2 -carboxylic acid-4-hydrogensulfateOne-potThree-component
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Effects of salvianolic acid-A on NIH/3T3 fibroblast proliferation,collagen synthesis and gene expression 被引量:25
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作者 Liu CH Hu YY +2 位作者 Wang XL Liu P Xu LM 《World Journal of Gastroenterology》 SCIE CAS CSCD 2000年第3期361-364,共4页
AIM To investigate the mechanisms ofsalvianolic acid A(SA-A)against liver fibrosisin vitro.METHODS NIH/3T3 fibroblasts were culturedroutinely,and incubated with 10<sup>-4</sup>mol/L-10<sup>-7</s... AIM To investigate the mechanisms ofsalvianolic acid A(SA-A)against liver fibrosisin vitro.METHODS NIH/3T3 fibroblasts were culturedroutinely,and incubated with 10<sup>-4</sup>mol/L-10<sup>-7</sup>mol/L SA-A for 22 h.The cell viability wasassayed by[<sup>3</sup>H]proline incorporation,cellproliferation by[<sup>3</sup>H]TdR incorporation,cellcollagen synthetic rate was measured with[<sup>3</sup>H]proline impulse and collagenase digestionmethod.The total RNA was prepared from thecontrol cells and the drug treated cellsrespectively,and α(1)I pro-collagen mRNAexpression was semi-quantitatively analyzedwith RT-PCR.RESULTS 10<sup>-4</sup>mol/L SA-A decreased cellviability and exerted some cytotoxiciy,while10<sup>-5</sup>mol/L-10<sup>-7</sup>mol/L SA-A did not affect cellviability,but inhibited cell proliferationsignificantly,and 10<sup>-6</sup>mol/L SA-A had the besteffect on cell viability among theseconcentrations of drugs.10<sup>-5</sup>mol/L-10<sup>-6</sup>mol/LSA-A inhibited intracellular collagen syntheticrate,but no significant influence on extracellularcollagen secretion.Both 10<sup>-5</sup>mol/L and10<sup>-6</sup>mol/L SA-A could decrease α(1)I pro-collagen mRNA expression remarkably.CONCLUSION SA-A had potent action againstliver fibrosis.It inhibited NIH/3T3 fibroblastproliferation,intracellular collagen syntheticrate and type I pro-collagen gene expression,which may be one of the main mechanisms of thedrug. 展开更多
关键词 salvianolic acid-A NIH/3T3 FIBROBLAST CELL VIABILITY CELL PROLIFERATION COLLAGEN gene expression
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Protective effects of lipoic acid-niacin dimers against blue light-induced oxidative damage to retinal pigment epithelium cells 被引量:4
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作者 Xiu-Lan Zou Yong-Zhen Yu +8 位作者 Hong-Hua Yu Guan-Feng Wang Rong-Biao Pi Zhe Xu Chu Zhang Wen-Jie Zhou Dan-Dan Li Xuan-Ge Chen Yu-Ping Zou 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2019年第8期1262-1271,共10页
AIM: To evaluate the protective effects of lipoic acid-niacin(N2 L) dimers against blue light(BL)-induced oxidative damage to human retinal pigment epithelium(hRPE) cells in vitro.METHODS: h RPE cells were divided int... AIM: To evaluate the protective effects of lipoic acid-niacin(N2 L) dimers against blue light(BL)-induced oxidative damage to human retinal pigment epithelium(hRPE) cells in vitro.METHODS: h RPE cells were divided into a control group(CG), a BL group, an N2 L plus BL irradiation group, an α-lipoic acid(ALA) plus BL group, an ALA-only group, and an N2 L-only group. hRPE cellular viability was detected by performing 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium(MTT) bromide assays, and apoptosis was evaluated by annexin-V-PE/7-AAD staining followed by flow cytometry. Ultrastructural changes in subcellular organelles were observed by transmission electron microscopy. Reactive oxygen species formation was assayed by flow cytometry. The expression levels of the apoptosis-related proteins BCL-2 associated X protein(BAX), B-cell leukmia/lymphoma 2(BCL-2), and caspase-3 were quantified by Western blot analysis.RESULTS: BL exposure with a light density of 4±0.5 mW/cm2 exceeding 6 h caused hRPE toxicity, whereas treatment with a high dose of N2 L(100 mol/L) or ALA(150 mol/L) maintained cell viability at control levels. BL exposure caused vacuole-like degeneration, mitochondrial swelling, and reduced microvillus formation;however, a high dose of N2 L or ALA maintained the ultrastructure of hRPE cells and their organelles. High doses of N2 L and ALA also protected hRPE cells from BL-induced apoptosis, which was confirmed by Western blot analysis: BCL-2 expression significantly increased, while BAX and caspase-3 expression slightly decreased compared to the CG.CONCLUSION: High-dose N2 L treatment(>100 mol/L) can reduce oxidative damage in degenerating hRPE cells exposed to BL with an efficacy similar to ALA. 展开更多
关键词 lipoic acid-niacin DIMERS RETINAL PIGMENT EPITHELIUM cell lipoic ACID oxidative stress reactive oxygen species apoptosis
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Photo-degradation of Acid-red 3B dye catalyzed by TiO_2 nanotubes 被引量:6
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作者 JIANG Fang ZHENG Shou-rong ZHENG Zheng XU Zhao-yi WANG Yan-jin 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2006年第4期783-787,共5页
TiO2 nanotube precursor was synthesized by the hydrothermal reaction of TiO2 powders with NaOH solution and the properties of the nanotube materials were tuned using different post-treatments. Transmission electron mi... TiO2 nanotube precursor was synthesized by the hydrothermal reaction of TiO2 powders with NaOH solution and the properties of the nanotube materials were tuned using different post-treatments. Transmission electron microscopic (TEM) observation revealed that the nanotube could be obtained by either a direct rinse with acid solution or rinse with distilled water followed by acid solution. The results of X-ray diffraction (XRD) and inductively coupled plasma (ICP) analysis indicated that the nanotube material was composed of H2Ti2O5·H2O. In addition, the photocatalytic activities of the resulting catalysts were found to be strongly dependent on the post-treatment. The results of the photocatalytic reaction showed that the degradation of Acid-red 3B dye fitted pseudo-zero-order kinetics and TiO2 nanotube prepared under direct rinse with acid solution exhibited a higher catalytic efficiency compared to other catalysts. 展开更多
关键词 TiO2 nanotube acid-red 3B photocatalysis hydrothermal reaction
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Efficient adsorption and desorption of Cu^(2+) by a novel acid-resistant magnetic weak acid resin 被引量:6
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作者 Man Cheng Zhang Qing Zhou +2 位作者 Yang Zhou Ai Min Li Chen Dong Shuang 《Chinese Chemical Letters》 SCIE CAS CSCD 2012年第11期1267-1270,共4页
A novel magnetic weak acid resin NDMC-1 was prepared in the presence of methyl acrylate (MA), divinylbenzene (DVB) and titanate coupling agent (TCA) coated γ-Fe203 particles. To evaluate the adsorption of Cu^2... A novel magnetic weak acid resin NDMC-1 was prepared in the presence of methyl acrylate (MA), divinylbenzene (DVB) and titanate coupling agent (TCA) coated γ-Fe203 particles. To evaluate the adsorption of Cu^2+ on the obtained resin NDMC- 1, another two magnetic resins NDMC-0 (the precursor of NDMC-1 without hydrolyzation) and NDMO-1 (the synthesized weak acid resin using oleic acid coated γ-Fe2O3) were chosen for comparison. The results showed that the carboxyl groups were formed after hydrolyzation, and NDMC-1 exhibited a greater adsorption capacity to Cu2~. The desorption experiment demonstrated that the desorption ratio at pH 2 (95.14%) was greatly higher than pH 3 (25.97%). Moreover, the magnetic resin NDMC-1 was proved to be stable at pH 2, extending the application of magnetic materials which were always considered to be acid-nor, resistant. 展开更多
关键词 acid-resistant Magnetic resin COPPER Adsorption behavior Desorpfion
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Isolation and Characterization of Acid-soluble Collagen and Pepsin-soluble Collagen from the Skin of Hybrid Sturgeon 被引量:7
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作者 WEI Pei LI Dan 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2019年第4期950-959,共10页
By using the wastes fish skin of sturgeon processed as a raw material, a macromolecule biomaterial of collagen was extracted. Acid-soluble collagen(ASC) and pepsin-soluble collagen(PSC) were successfully isolated from... By using the wastes fish skin of sturgeon processed as a raw material, a macromolecule biomaterial of collagen was extracted. Acid-soluble collagen(ASC) and pepsin-soluble collagen(PSC) were successfully isolated from the skin of hybrid sturgeon with two extraction methods. The yields of ASC and PSC based on the wet weight of skin were 5.73 ± 0.11% and 10.26 ± 0.39%, respectively. The denaturation and melting points of ASC(26.83 ℃ and 110.49 ℃) and PSC(26.54 ℃ and 102.99 ℃) were assessed by Circular dichroism(CD) and Differential scanning calorimetry(DSC). ASC and PSC appeared to be dense sheet-like film linked by random-coiled filaments under scanning electron microscopy(SEM). Sodium dodecyl sulfate-polyacrylamide gel electrophoresis(SDS-PAGE) and Fourier transform infrared spectroscopy(FTIR) confirmed that both the ASC and PSC were Type I collagen and maintained a complete triple helix structure. These results indicated that both ASC and PSC possessed good biological activity and could be widely used in medical biomaterials and other fields. 展开更多
关键词 hybrid STURGEON acid-soluble collagen(ASC) pepsin-soluble collagen(PSC) isolation characterization
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Two new b-hydroxy amino acid-coupled secoiridoids from the flower buds of Lonicera japonica:Isolation,structure elucidation,semisynthesis,and biological activities 被引量:28
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作者 Wei-Xia Song Yong-Chun Yang Jian-Gong Shi 《Chinese Chemical Letters》 SCIE CAS CSCD 2014年第9期1215-1219,共5页
Two new β-hydroxy amino acid-coupled secoiridoids, named serinosecologanin (1) and threoninose- cologanin (2), were isolated from an aqueous extract of the flower buds of Lonicera japonica. Their uncommon structu... Two new β-hydroxy amino acid-coupled secoiridoids, named serinosecologanin (1) and threoninose- cologanin (2), were isolated from an aqueous extract of the flower buds of Lonicera japonica. Their uncommon structures including absolute configurations were determined by spectroscopic data analysis, and confirmed by semisynthesis from the co-occurring secologanin (3) and secologanic acid (4). Compounds 1 and 2 exhibited resistant activity against β-glucosidase from almonds and hesperidinase from Aspergillus niger, they also showed activity against the release of glucuronidase in rat polymorphonuclear leukocytes induced by the platelet-activating factor with inhibition rates of (34.9 ±3.1 )% and (53.6 ± 2.6)%, respectively. 展开更多
关键词 Lonicera japonicaCaprifoliaceae β-Hydroxy amino acid-coupled secoirridoidIsolationStructure elucidationSemisynthesisBiological activity
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Antibacterial Activity of 9-Octadecanoic Acid-Hexadecanoic Acid-Tetrahydrofuran-3,4-Diyl Ester from Neem Oil 被引量:3
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作者 PU Zhong-hui ZHANG Yu-qun +4 位作者 YIN Zhong-qiong XU Jiao JIA Ren-yong LU Yang YANG Fan 《Agricultural Sciences in China》 CSCD 2010年第8期1236-1240,共5页
The 9-octadecanoic acid-hexadecanoic acid-tetrahydrofuran-3,4-diyl ester from neem oil was investigated for antibacterial activity against three bacterial strains viz., Staphylococcus aureus ATCC No. 25923, Escherichi... The 9-octadecanoic acid-hexadecanoic acid-tetrahydrofuran-3,4-diyl ester from neem oil was investigated for antibacterial activity against three bacterial strains viz., Staphylococcus aureus ATCC No. 25923, Escherichia coli ATCC No. 44102 and Salmonella sp. ATCC No. 50 041 in vitro. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values of the 9-octadecanoic acid-hexadecanoic acid-tetrahydrofuran-3,4-diyl ester were determined by using the broth microdilution dilution (BMD) method at different concentrations ranging from 20 to 0.625 mg mL-1. Its time-inhibition curve against E. coli was also tested and showed that the MIC values for the bacterial strains S. aureus, E. coli and Salmonella sp. were 20, 5 and 10 mg mL-1, respectively. Its MBC values were 20, 20 and 10 mg mL-1, respectively. The antibacterial activity of 9-octadecanoic acid-hexadecanoic acid-tetrahydrofuran-3,4-diyl ester against three strain tested showed the relationship with time and concentration. 展开更多
关键词 Azadiraehta indica A. Juss neem oil MIC MBC time-inhibition curve 9-octadecanoic acid-hexadecanoic acid-tetrahydro furan-3 4-diyl ester
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Effect of Chitosan Coating on the Properties of Poly(glycolic acid-lactic acid)Thread-Embedding Material 被引量:1
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作者 徐晓霞 危惠敏 +1 位作者 赵俐 张佩华 《Journal of Donghua University(English Edition)》 EI CAS 2017年第6期722-725,共4页
Poly( glycolic acid-lactic acid)( PGLA) threadembedding material was modified by chitosan coating which could improve the rigidity,hydrophilicity and moisture absorption of the material,and produced better stimulation... Poly( glycolic acid-lactic acid)( PGLA) threadembedding material was modified by chitosan coating which could improve the rigidity,hydrophilicity and moisture absorption of the material,and produced better stimulation effect. Thus,this kind of thread-embedding materials which can be buried into acupuncture points to produce a long-time stimulation is popular in the acupuncture and moxibustion therapies. The variation tendencies of diameter,weight, hydrophilicity, and flexibility of the samples under the change of chitosan coating concentration,coating time and coating times were studied respectively. The results showed that the hydrophilicity,weight,and rigidity after coating rose in a certain range with the increase of coating time,coating times and coating concentration. The coating time had little influence on the diameter of fiber. 展开更多
关键词 poly(glycolic acid-latic acid)(PGLA) thread-embedding chitosan coating HYDROPHILICITY FLEXIBILITY RIGIDITY
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Effect of Uric-acid-lowering Therapy on Progression of Chronic Kidney Disease: A Meta-analysis 被引量:2
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作者 张叶芳 何凡 +5 位作者 丁红晖 代维 张茜 栾宏 吕永曼 曾红兵 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2014年第4期476-481,共6页
The efficacy and safety of uric-acid-lowering therapy (UALT) on slowing the progression of chronic kidney disease (CKD) accompanied by hyperuricemia were assessed. We searched Cochrane Library, PubMed, EMbase, CNK... The efficacy and safety of uric-acid-lowering therapy (UALT) on slowing the progression of chronic kidney disease (CKD) accompanied by hyperuricemia were assessed. We searched Cochrane Library, PubMed, EMbase, CNKI, Wanfang and Vip databases up to November 15, 2012 for randomized controlled trials (RCTs) which compared the effect of UALT to control therapy in hyperuricemic patients secondary to CKD, and then performed quality evaluation and meta-analysis on the included studies. Seven RCTs involving 451 cases were included. UALT delayed the increase of serum creatinine (MD=-62.55 μol/L, 95% CI: -98.10 to -26.99) and blood urea nitrogen (MD= -6.15 mmol/L, 95% CI -8.17 to -4.13) as well as the decrease of glomerular filtration rate [MD=5.65 mL/(min.l.73 m2), 95% CI: 1.88 to 9.41], decreased systolic blood pressure (SBP) (MD= -6.08 mmHg, 95% CI: -11.67 to -0.49), and reduced the risk of the renal disease progression (RR=0.30, 95% CI: 0.19 to 0.46). However, there was no statistically significant difference in 24-h urinary protein quantity and diastolic blood pressure (P〉0.05). We identified that UALT could delay the progression of CKD with secondary hyperuricemia. And this also indirectly proved that hyperuricemia was a risk factor for the CKD progression. 展开更多
关键词 HYPERURICEMIA chronic kidney disease uric-acid-lowering META-ANALYSIS
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Two Dehydroabietic Acid-based Arylamines: Synthesis, Crystal Structure and Fluorescent Properties 被引量:2
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作者 高宏 宋杰 +1 位作者 商士斌 宋湛谦 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2013年第3期396-402,共7页
Two dehydroabietic acid-based arylamines have been synthesized and characterized by FTIR, 1H NMR, 13C NMR, MS spectra and elemental analysis. Their spatial structures were determined by X-ray diffraction analysis. UV-... Two dehydroabietic acid-based arylamines have been synthesized and characterized by FTIR, 1H NMR, 13C NMR, MS spectra and elemental analysis. Their spatial structures were determined by X-ray diffraction analysis. UV-Vis absorption and fluorescence spectral characteristics of these compounds in methanol were investigated. Their fluorescence emission spectra in different polarity solvents were further evaluated. Fluorescent properties and structural relationship of the compounds showed that fluorescence intensity and quantum yield inversely increase with the non-coplanar degree. In addition, the solvent polarity has different effects on the fluorescence emission spectra of two compounds. 展开更多
关键词 dehydroabietic acid-based arylamine SYNTHESIS crystal structure fluorescent property
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Acid-base characterization of foursulfide minerals 被引量:1
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作者 Lin Yuhuan(Research Center for Eco-Environmentai Sciences, Chinese Academy of Sciences, Beijing 100085, China)George W. Bailey(Environmental Research Laboratory Office of Research and Development, U. S. Environmental Protection Agency, Athens, Georgia 306 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1994年第2期215-223,共9页
The amphoteric properties of four sulfide minerals were characterized byacidimetric-alkalimetric titration. Chalcocite, galena, and sphalerite were found to bediprotic acids, while pyrite was determined to be a tripro... The amphoteric properties of four sulfide minerals were characterized byacidimetric-alkalimetric titration. Chalcocite, galena, and sphalerite were found to bediprotic acids, while pyrite was determined to be a triprotic acid. Intrinsic acidity con-stants for the four minerals are as follows: chalcocite-pK_(a1)=5.25, pK_(a2)=9.68;galena- pK_(a1)=5.26, pK_(a2)=9.62; sphalente- pK_(a1)= 5.08, pK_(a2)= 9.13;and pyrite - pK_(a1) = 3.50,pK_(a2)=5.32, pK_(a3)=9.81. 展开更多
关键词 acid-base titration CHALCOCITE GALENA pynte sphalerite.
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Characterization of Turbot(Scophthalmus maximus) Skin and the Extracted Acid-Soluble Collagen 被引量:1
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作者 SUN Jianan ZHANG Jingjing +3 位作者 ZHAO Dandan XUE Changhu LIU Zhen MAO Xiangzhao 《Journal of Ocean University of China》 SCIE CAS CSCD 2019年第3期687-692,共6页
The biochemical composition of the turbot skin was investigated. The moisture level of the skin was found to be 51.4%. Based on dry matter content, there were relatively high protein(82.1%) and lipid(13.1%) concentrat... The biochemical composition of the turbot skin was investigated. The moisture level of the skin was found to be 51.4%. Based on dry matter content, there were relatively high protein(82.1%) and lipid(13.1%) concentrations in the turbot skin. Mineral element analysis revealed that the turbot skin had high Ca content(2069.0 mg kg^-1), and the concentrations of toxic heavy metals Hg and Pb were less than 0.005 mg kg^-1, which indicates that the turbot skin is a safe resource for collagen production. The sodium dodecyl sulfate-polyacrylamide gel electrophoresis(SDS-PAGE) analysis showed that acid-soluble collagen(ASC) extracted from the turbot skin was type-I collagen. The imino acid content of the ASC was 241.6 per 1000 amino acids, which suggests a relatively high denaturation temperature. The Fourier transform infrared(FTIR) spectra of ASC reflected a highly stable structure, and the measured denaturation temperature of ASC was 29.5℃, which is higher than those from many temperate fishes. ASC was the most soluble at pH 4.0, and when the pH values were below or above 4.0, the solubility decreased rapidly. The ASC exhibited a relatively high solubility when NaCl concentration was lower than 2%. These results show that turbo skin can be employed as a source for producing collagen with high quality. 展开更多
关键词 TURBOT SKIN acid-soluble COLLAGEN BYPRODUCT extraction COLLAGEN
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Identification and Function of Acid-sensing Ion Channels in RAW 264.7 Macrophage Cells 被引量:2
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作者 Lan NI Peng FANG +4 位作者 Zhuang-li HU Hai-yun ZHOU Jian-guo CHEN Fang WANG You JIN 《Current Medical Science》 SCIE CAS 2018年第3期436-442,共7页
Activation of acid-sensing ion channels (ASICs) plays an important role in neuroinflammation. Macrophage recruitment to the sites of inflammation is an essential step in host defense. ASIC1 and ASIC3 have been repor... Activation of acid-sensing ion channels (ASICs) plays an important role in neuroinflammation. Macrophage recruitment to the sites of inflammation is an essential step in host defense. ASIC1 and ASIC3 have been reported to mediate the endocytosis and maturation of bone marrow derived macrophages. However, the expression and inflammation-related functions of ASICs in RAW 264.7 cells, another common macrophage, are still elusive. In the present study, we first demonstrated the presence of ASIC 1, ASIC2a and ASIC3 in RAW 264.7 macrophage cell line by using reverse transcriptase polymerase chain reaction (RT-PCR), Western blotting and immunofluorescence experiments. The non-specific ASICs inhibitor amiloride and specific homomeric ASICla blocker PcTxl reduced the production of iNOS and COX-2 by LPS-induced activating RAW 264.7 cells. Furthermore, not only amiloride but also PcTxl inhibited the migration and LPS-induced apoptosis of RAW 264.7 cells. Taken together, our findings suggest that ASICs promote the inflammatory response and apoptosis of RAW 264.7 cells, and ASICs may serve as a potential novel target for immunological disease therapy. 展开更多
关键词 acid-sensing ion channels (ASICs) RAW 264.7 cells INFLAMMATION apoptosis MIGRATION
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Determination of pKa values of alendronate sodium in aqueous solution by piecewise linear regression based on acid-base potentiometric titration 被引量:2
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作者 Jing Ke Hanfei Dou +3 位作者 Ximin Zhang Dushimabararezi Serge Uhagaze Xiali Ding Yuming Dong 《Journal of Pharmaceutical Analysis》 SCIE CAS 2016年第6期404-409,共6页
As a mono-sodium salt form of alendronic acid,alendronate sodium presents multi-level ionization for the dissociation of its four hydroxyl groups.The dissociation constants of alendronate sodium were determined in thi... As a mono-sodium salt form of alendronic acid,alendronate sodium presents multi-level ionization for the dissociation of its four hydroxyl groups.The dissociation constants of alendronate sodium were determined in this work by studying the piecewise linear relationship between volume of titrant and p H value based on acidbase potentiometric titration reaction.The distribution curves of alendronate sodium were drawn according to the determined p Ka values.There were 4 dissociation constants(pKa_1=2.43,pKa_2=7.55,pKa_3=10.80,pKa_4=11.99,respectively) of alendronate sodium,and 12 existing forms,of which 4 could be ignored,existing in different p H environments. 展开更多
关键词 Dissociation CONSTANTS ALENDRONATE SODIUM Distribution curve Piecewise linear regression acid-BASE POTENTIOMETRIC TITRATION
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Studies on synthesis and property of novel acid-base proton exchange membranes 被引量:1
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作者 Yong Fang Liang Hai Yan Pan Xiu Ling Zhu Yao Xia Zhang Xi Gao Jian 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第5期609-612,共4页
Sulfonated poly(phthalazinone)s (SPPENK, SPPESK and SPPBEK) were prepared by direct polymerization reaction from sulfonated monomers. The novel acid-base membranes were composed of sulfonated polymers as the acidi... Sulfonated poly(phthalazinone)s (SPPENK, SPPESK and SPPBEK) were prepared by direct polymerization reaction from sulfonated monomers. The novel acid-base membranes were composed of sulfonated polymers as the acidic compounds, and polyetherimide (PEI) as the basic compounds, casting from their N-methylpyrrolidone (NMP) solution directly onto clean glass plates at 60 ℃ aiming at enhancing membrane toughness and other relative properties. The resulted acid-base composite membranes had excellent resistance to swelling, thermo-stability, hydrolysis resistance and oxidative resistance properties with highly ion-exchange capacity (IEC). 展开更多
关键词 acid-base composite membrane PEM STABILITY SULFONATION
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Sinulariol-D,Sinularial-A和Sinularic Acid-A前体化合物的合成 被引量:1
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作者 岑文 邢雅成 李裕林 《高等学校化学学报》 SCIE EI CAS CSCD 北大核心 1998年第7期1086-1089,共4页
报道了以香叶醇为起始原料经9步反应合成Sinulariol-D,Sinularial-A和SinularicAcid-A的前体化合物(E,E,E)-2,6,10,14-四甲基-2,3-环氧-16-苯硫醚基十六碳-6,... 报道了以香叶醇为起始原料经9步反应合成Sinulariol-D,Sinularial-A和SinularicAcid-A的前体化合物(E,E,E)-2,6,10,14-四甲基-2,3-环氧-16-苯硫醚基十六碳-6,10。 展开更多
关键词 大环二萜 Sinulariol-D Sinulrial-A 合成
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Crystallization behavior of zeolite beta from acid-leached metakaolin 被引量:2
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作者 Li Qiang Zhang Ying +2 位作者 Cao Zhijun Gao Wei Cui Lishan 《Petroleum Science》 SCIE CAS CSCD 2010年第4期541-546,共6页
Well-crystallized zeolite beta was synthesized by using acid-leached metakaolin as the silica-alumina source and tetraethylammonium hydroxide structure-directing agent.The influence of the composition of the reaction ... Well-crystallized zeolite beta was synthesized by using acid-leached metakaolin as the silica-alumina source and tetraethylammonium hydroxide structure-directing agent.The influence of the composition of the reaction mixture on product crystallinity was investigated,and the crystallization process was studied by examining solid samples obtained at different synthesis times.Results showed that the acid-leached metakaolin was fully converted into soluble aluminum and silicon species,which is crucial for the formation of well-crystallized zeolite beta.At the beginning of the crystallization process,these soluble aluminum and silicon species formed a aluminum-rich intermediate structure with layer morphology.With the crystallization proceeding,more silicon species were incorporated into the zeolite beta framework and the layered structure was changed into spherical particles of zeolite beta with high SiO 2 /Al 2 O 3 ratio and crystallinity. 展开更多
关键词 Zeolite beta acid-leached metakaolin tetraethylammonium hydroxide (TEAOH) liquid phase transformation mechanism
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