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First total synthesis of natural products cajanolactone A and cajanonic acid A 被引量:7
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作者 Wen-Zhang Chen Ling-Ling Fan +4 位作者 Hai-Tao Xiao Ying Zhou Wan Xiao Jian-Ta Wang Lei Tang 《Chinese Chemical Letters》 SCIE CAS CSCD 2014年第5期749-751,共3页
First total synthesis of cajanolactone A and cajanonic acid A has been achieved through steps of anion–anion condensations,cyclization,Williams etherification,selective demethylation,1 3-sigmatropic rearrangement and... First total synthesis of cajanolactone A and cajanonic acid A has been achieved through steps of anion–anion condensations,cyclization,Williams etherification,selective demethylation,1 3-sigmatropic rearrangement and hydrolysis.This work provides an efficient method for future cajanonic acid A derivatives synthesis. 展开更多
关键词 total synthesis Cajanolactone A Cajanonic acid A
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Can tranexamic acid change preoperative anemia management during total joint arthroplasty? 被引量:5
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作者 Duy L Phan Joseph B Rinehart Ran Schwarzkopf 《World Journal of Orthopedics》 2015年第7期521-527,共7页
AIM: To investigate the postoperative transfusion and complication rates of anemic and nonanemic total joint arthroplasty patients given tranexamic acid(TXA).METHODS: A cross-sectional prospective study was conducted ... AIM: To investigate the postoperative transfusion and complication rates of anemic and nonanemic total joint arthroplasty patients given tranexamic acid(TXA).METHODS: A cross-sectional prospective study was conducted of primary hip and knee arthroplasty cases performed from 11/2012 to 6/2014. Exclusion criteria included revision arthroplasty, bilateral arthroplasty, acute arthroplasty after fracture, and contraindication to TXA. Patients were screened prior to surgery, with anemia was defined as hemoglobin of less than 12 g/d L for females and of less than 13 g/d L for males. Patients were divided into four different groups, based on the type of arthroplasty(total hip or total knee) and hemoglobin status(anemic or nonanemic). Intraoperatively, all patients received 2 g of intravenous TXA during surgery. Postoperatively, allogeneic blood transfusion(ABT) was directed by both clinical symptomsand relative hemoglobin change. Complications were recorded within the first two weeks after surgery and included thromboembolism, infection, and wound breakdown. The differences in transfusion and complication rates, as well as the relative hemoglobin change, were compared between anemic and nonanemic groups.RESULTS: A total of 232 patients undergoing primary joint arthroplasty were included in the study. For the total hip arthroplasty cohort, 21%(18/84) of patients presented with preoperative anemia. Two patients in the anemic group and two patients in the nonanemic group needed ABTs; this was not significantly different(P = 0.20). One patient in the anemic group presented with a deep venous thromboembolism while no patients in the nonanemic group had an acute complication; this was not significantly different(P = 0.21). For nonanemic patients, the average change in hemoglobin was 2.73 ± 1.17 g/d L. For anemic patients, the average change in hemoglobin was 2.28 ± 0.96 g/d L. Between the two groups, the hemoglobin difference of 0.45 g/d L was not significant(P = 0.13). For the total knee arthroplasty cohort, 18%(26/148) of patients presented with preoperative anemia. No patients in either group required a blood transfusion or had an acute postoperative complication. For nonanemic patients, the average change in hemoglobin was 1.85 ± 0.79 g/d L. For anemic patients, the average change in hemoglobin was 1.09 ± 0.58 g/d L. Between the two groups, the hemoglobin difference of 0.76 g/d L was significant(P < 0.001). CONCLUSION: TXA administration results in low transfusion and complication rates and may be a useful adjunct for TJA patients with preoperative anemia. 展开更多
关键词 total KNEE REPLACEMENT Tranexamic acid total HIP REPLACEMENT PREOPERATIVE ANEMIA
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Relationship of nocturnal concentrations of melatonin, gamma-aminobutyric acid and total antioxidants in peripheral blood with insomnia after stroke: study protocol for a prospective non-randomized controlled trial 被引量:53
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作者 Wei Zhang Fang Li Tong Zhang 《Neural Regeneration Research》 SCIE CAS CSCD 2017年第8期1299-1307,共9页
Melatonin and gamma-aminobutyric acid(GABA) have been shown to regulate sleep. The nocturnal concentrations of melatonin, GABA and total antioxidants may relate to insomnia in stroke patients. In this prospective si... Melatonin and gamma-aminobutyric acid(GABA) have been shown to regulate sleep. The nocturnal concentrations of melatonin, GABA and total antioxidants may relate to insomnia in stroke patients. In this prospective single-center non-randomized controlled clinical trial performed in the China Rehabilitation Research Center, we analyzed the relationship of nocturnal concentrations of melatonin, GABA and total antioxidants with insomnia after stroke. Patients during rehabilitation of stroke were recruited and assigned to the insomnia group or non-insomnia group. Simultaneously, persons without stroke or insomnia served as normal controls. Each group contained 25 cases. The primary outcome was nocturnal concentrations of melatonin, GABA and total antioxidants in peripheral blood. The secondary outcomes were Pittsburgh Sleep Quality Index, Insomnia Severity Index, Epworth Sleepiness Scale, Fatigue Severity Scale, Morningness-Eveningness Questionnaire(Chinese version), and National Institute of Health Stroke Scale. The relationship of nocturnal concentrations of melatonin, GABA and total antioxidants with insomnia after stroke was analyzed and showed that they were lower in the insomnia group than in the non-insomnia group. The severity of stroke was higher in the insomnia group than in the non-insomnia group. Correlation analysis demonstrated that the nocturnal concentrations of melatonin and GABA were associated with insomnia after stroke. This trial was registered at Clinical Trials.gov, identifier: NCT03202121. 展开更多
关键词 nerve regeneration STROKE INSOMNIA MELATONIN γ-aminobutyric acid total antioxidants sleep-related scales National Institute ofHealth Stroke Scale neural regeneration
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Optimization of Extraction Process of Total Flavonoids and Chlorogenic Acid from Flos Lonicerae by Orthogonal Experiment 被引量:1
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作者 Huasheng LI Zhenhua ZHOU Shouyong TANG 《Medicinal Plant》 CAS 2019年第5期64-68,共5页
[Objectives]To explore the process of simultaneous extracting total flavonoids and chlorogenic acid from Flos Lonicerae by pressure assisted extraction.[Methods]Based on the single factor experiment,orthogonal experim... [Objectives]To explore the process of simultaneous extracting total flavonoids and chlorogenic acid from Flos Lonicerae by pressure assisted extraction.[Methods]Based on the single factor experiment,orthogonal experiments were carried out to investigate the effects of solvent concentration,solid-to-liquid ratio,extraction pressure,extraction time and extraction temperature on the extraction rate of total flavonoids and chlorogenic acid.[Results]The results showed that the extraction pressure had a significant effect on the extraction of two kinds of chemical constituents from F.Lonicerae.The optimum process conditions were as follows:solvent concentration was 60%,solid-liquid ratio was 1∶20(g/mL),extraction pressure was 2 MPa,extraction time was 30 min,extraction temperature was 70℃.The process conditions are stable,and the extraction efficiency is higher than that of ultrasonic assisted extraction method.Under the test conditions,the extraction rates of total flavonoids and chlorogenic acids were respectively 15.66%and 3.89%.[Conclusions]This study provides a new theoretical basis for the development and utilization of F.Lonicerae. 展开更多
关键词 Flos Lonicerae PRESSURE ASSISTED EXTRACTION total FLAVONOIDS Chlorogenic acid
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Evaluation of the diagnostic value of total bile acids/platelets in HBV related liver fibrosis
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作者 SUN Tian-Yi HUANG Sheng-kai SUN Long 《Journal of Hainan Medical University》 CAS 2023年第20期51-55,共5页
Objective:Explore the diagnostic value of total bile acids/platelets in HBV related liver fibrosis.Methods:160 patients with chronic HBV infection admitted to the Infection Department of the First Affiliated Hospital ... Objective:Explore the diagnostic value of total bile acids/platelets in HBV related liver fibrosis.Methods:160 patients with chronic HBV infection admitted to the Infection Department of the First Affiliated Hospital of Hainan Medical College from February 2021 to December 2022 were selected.They were divided into two groups based on the degree of liver fibrosis detected by liver biopsy:significant liver fibrosis group and non-significant liver fibrosis group.The total bile acid/blood platelet levels and their correlation with liver fibrosis in the two groups were compared and observed,and the efficacy of other non-invasive liver fibrosis diagnostic models was evaluated.Results:(1)Compared with the non-significant liver fibrosis group,the significant liver fibrosis group showed an increase in total bile acid levels,a decrease in platelet levels,and a significant increase in total bile acid/platelet levels(P<0.05).(2)Platelets decrease with the increase of liver fibrosis degree,total bile acids increase with the increase of liver fibrosis degree,and total bile acids/platelets increase with the increase of liver fibrosis degree.(3)The area under the curve(AUC)of total bile acid/platelet,APRI,FIB-4,and elastography in diagnosing the degree of liver fibrosis were 0.69,0.57,0.56,and 0.68,respectively.Conclusions:The diagnostic efficacy of total bile acids/platelets in diagnosing HBV related liver fibrosis is no less than that of other liver fibrosis diagnostic methods,and it is non-invasive,simple,and convenient,which is worthy of further clinical promotion and validation. 展开更多
关键词 total bile acids PLATELETS Liver fibrosis Hepatitis B virus
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Total DNA of Glycyrrhiza uralensis transformed into Hansenula anomala by ion implantation:Preparing Glycyrrhizic acid in recombined yeasts 被引量:1
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作者 Jin Xiang Lue Jie +1 位作者 Ma Yuan Mao Peihong 《Nuclear Science and Techniques》 SCIE CAS CSCD 2010年第6期347-351,共5页
Glycyrrhizic acid(GA) in Glycyrrhiza uralensis(G.uralensis) is physiologically active.In this study,the total DNA of wild G.uralensis was randomly transformed into Hansenula anomala by implantation of low-energy Ar^+ ... Glycyrrhizic acid(GA) in Glycyrrhiza uralensis(G.uralensis) is physiologically active.In this study,the total DNA of wild G.uralensis was randomly transformed into Hansenula anomala by implantation of low-energy Ar^+ and N^+,to produce five recombinant yeast strains relating to biological synthesis of the GA or Glycyrrhetinic acid (GAs).After culturing in liquid medium for 96 h,the resultant GA,18α-GAs and 18β-Gas were determined by reversed-phase high performance liquid chromatography(RP-HPLC),and the corresponding concentrations were 114.49,0.56,and 0.81 mg·L^(-1).After one hundred primers were analyzed with random amplified polymorphic DNA (RAPD),the seven different DNA fragments were produced by the N7059 strain of recombined yeasts,and,the polymerase chain reaction(PCR) verified that one of them came from the genome of G.uralensis,indicating a successful transfer of genetic information by ion implantation. 展开更多
关键词 异常汉逊酵母 DNA转化 重组酵母 离子注入 甘草酸 乌拉尔甘草 随机扩增多态性DNA 反相高效液相色谱法
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Dysregulation of bile acid signal transduction causes neurological dysfunction in cirrhosis rats
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作者 Chao Ren Li Cha +7 位作者 Shu-Yue Huang Guo-Hui Bai Jin-Hui Li Xin Xiong Yu-Xing Feng Dui-Ping Feng Long Gao Jin-Yu Li 《World Journal of Hepatology》 2025年第3期140-151,共12页
BACKGROUND The pathogenesis of hepatic encephalopathy(HE)remains unclear,and the classical theory of ammonia toxicity lacks sufficient justification.AIM To investigate the potential of bile acids as intervention targe... BACKGROUND The pathogenesis of hepatic encephalopathy(HE)remains unclear,and the classical theory of ammonia toxicity lacks sufficient justification.AIM To investigate the potential of bile acids as intervention targets for HE.METHODS This study employed 42 wild-type male SD rats weighing 200±20 g.Using a random number table method,two rats were randomly selected to undergo common bile duct ligation(BDL).The remaining 40 rats were randomly assigned to four groups serving as controls:The vehicle+control diet(VC)group,the thioacetamide(TAA)group,the TAA+total bile acids(TAAT)group,and the TAA+cholestyramine(TAAC)group.Except for the VC group,all rats were intraperitoneally injected with 100 mg/kg TAA solution once daily for ten consecutive days to establish a HE model.Simultaneously,the TAAT and TAAC groups were administered a diet containing 0.3%bile acids(derived from BDL rats)and 2%cholestyramine,respectively,by gavage for ten days.For the BDL rat model group,the common BDL procedure was performed following the aforementioned protocol.After four weeks,laparotomy revealed swollen bile ducts at the ligation site,and bile was collected.Following successful modeling,behavioral tests,including the elevated plus maze and open field test,were conducted to assess the HE status of the rats.Peripheral blood,liver,and cerebral cortex tissue samples were collected,and the total bile acid content in the serum and cerebral cortex was measured using an enzyme cycling method.The levels of inflammatory factors in the serum and cerebral cortex were analyzed using enzyme-linked immunosorbent assay.Liver histological examination was performed using the hematoxylin-eosin double-labeling method.Reverse transcription polymerase chain reaction,western blot,immunohistochemistry,and other techniques were employed to observe the expression of microglial activation marker ionized calcium-binding adaptor molecule-1 and Takeda G protein-coupled receptor 5(TGR5)protein.RESULTS Compared to the VC group,the TAA group exhibited an exacerbation of HE in rats.The total bile acid content,proinflammatory factors[interleukin-1β(IL-1β),IL-6],and the anti-inflammatory factor IL-10 in both the serum and cerebral cortex were significantly elevated.Similarly,the expression of the TGR5 receptor in the cerebral cortex was upregulated.To investigate the impact of total bile acids on HE in rats,comparisons were made with the TAA group.In the TAAT group,the severity of HE was further aggravated,accompanied by increased total bile acid content in the serum and cerebral cortex,elevated pro-inflammatory factors(IL-1β,IL-6),reduced levels of the antiinflammatory factor IL-10,and decreased expression of the TGR5 receptor in the cerebral cortex.In the TAAC group,the severity of HE was alleviated.This group showed reductions in total bile acid content in the serum and cerebral cortex,decreased pro-inflammatory factors(IL-1β,IL-6),increased levels of the anti-inflammatory factor IL-10,and enhanced expression of the TGR5 receptor in the cerebral cortex.CONCLUSION This study demonstrated that the total bile acid content in the serum and cerebral cortex of TAA-induced liver cirrhosis rats was elevated.Furthermore,total bile acids exacerbate the progression of HE in rats.This effect may be attributed to bile acids’involvement in the development of neurological dysfunction by mediating TGR5 expression and regulating neuroinflammation. 展开更多
关键词 Hepatic encephalopathy total bile acid THIOACETAMIDE G protein-coupled bile acid receptor 1 Liver cirrhosis
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Effect of Citric Acid on the Total Monomeric Anthocyanins and Antioxidant Activity of Liquor Made from Unprocessed Purple Leafed TRFK 306 Kenyan Tea Clone
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作者 Emily C. Kilel John K. Wanyoko +1 位作者 Abdul K. Faraj Peninah Ngoda 《Food and Nutrition Sciences》 2019年第10期1191-1201,共11页
A study was conducted to find out the effect of citric acid on total monomeric anthocyanins and antioxidant activity of liquor made from unprocessed purple-leafed TRFK 306 Kenyan tea, brewed at various time/temperatur... A study was conducted to find out the effect of citric acid on total monomeric anthocyanins and antioxidant activity of liquor made from unprocessed purple-leafed TRFK 306 Kenyan tea, brewed at various time/temperature combinations. Most purple tea consumers usually brew the tea leaves then add some lemon juice before consuming it. Citric acid was used here to mimic the use of lemon juice. Documentation on the quality of such a brew is scanty and the effect of acid on its quality is equally scanty. The current study used brewing time/temperature combinations of 5, 10 and 15 minutes with 70&deg;C and 92&deg;C drinking water. Total monomeric anthocyanins were analysed using UV-1800 spectrophotometer (Shimadzu, Japan) while DDPH method was used to assay for antioxidant activity. Citric acid concentration of 0, 0.1% to 0.5% was used to check their effect on the brews with the highest total anthocyanins and antioxidant activity. The results showed that brewing temperature of 70&deg;C had 9.5 mg/L to 27.7 mg/L, with 5 minutes brewing time being the highest. Temperature of 92&deg;C had 37.5 mg/L to 92 mg/L with 5 minutes brewing time having the highest total monomeric anthocyanins. Antioxidant activity of 92&deg;C brewing temperature ranged from 90.7% to 92.0%. Total monomeric anthocyanins increased with increased citric acid concentration up to 0.3% before it decreases while for antioxidant activity, it decreased with addition of citric acid. It was concluded that for maximum anthocyanins extraction, 5 minutes brewing time is the best while ten minutes brewing time could give optimum antioxidant activity. 展开更多
关键词 TRFK 306 total MONOMERIC Anthocyanins Antioxidant Activity Citric acid BREWING Conditions
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Effect of lactic acid bacteria and propionic acid on conservation characteristics,aerobic stability and in vitro gas production kinetics and digestibility of whole-crop corn based total mixed ration silage 被引量:19
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作者 CHEN Lei YUAN Xian-jun +3 位作者 LI Jun-feng WANG Si-ran DONG Zhi-hao SHAO Tao 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第7期1592-1600,共9页
This study was conducted to evaluate the effect of lactic acid bacteria and propionic acid on the fermentation quality, aer- obic stability and in vitro gas production kinetics and digestibility of whole-crop corn bas... This study was conducted to evaluate the effect of lactic acid bacteria and propionic acid on the fermentation quality, aer- obic stability and in vitro gas production kinetics and digestibility of whole-crop corn based totalmixed ration (TMR) silage. Total mixed ration was ensiled with four treatments: (1) no additives (control); (2) an inoculant (Lactobacillus plantarum) (L); (3) propionicacid (P); (4) propionic acid+lactic acid bacteria (PL). All treatments were ensiled in laboratory-scale silos for 45 days, and then subjected to an aerobic stability test for12 days. Further, four TMR silages were incubated in vitro with buffered rumen fluid to study in vitro gas production kinetics and digestibility. The results indicated that all TMR silages had good fermentation characteristics with low pH (〈3.80) and ammonia nitrogen (NH3-N) contents, and high lactic acid contents as well as Flieg points. Addition of L further improved TMR silage quality with more lactic acid production. Addition of P and PL decreased lactic acid and NH3-N contents of TMR silage compared to the control (P〈0.05). After 12 days aerobic exposure, P and PL silages remained stable, but L and the control silages deteriorated as indicated by a reduction in lactic acid and an increase in pH, and numbers of yeast. Compared to the control, addition of L had no effects on TMR silage in terms of 72 h cumulative gas production, in vitro dry matter digestibility, metabolizable energy, net energy for lactation and short chain fatty acids, whereas addition of PL significantly (P〈0.05) increased them. L silage had higher (P〈0.05) in vitro neutral detergent fiber digestibility than the control silage. The results of our study suggested that TMR silage prepared with whole-crop corn can be well preserved with or without additives. Furthermore, the findings of this study suggested that propionic acid is compatible with lactic acid bacteria inoculants, and when used together, although they reduced lactic acid production of TMR silage, they improved aerobic stability and in vitro nutrients digestibility of TMR silage. 展开更多
关键词 lactic acid bacteria propionic acid fermentation quality aerobic stability in vitro digestibility total mixed rationsilage
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中药炮制辅料米泔水质量标准研究
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作者 王光函 鞠俭奎 +5 位作者 辛旭阳 邹桂欣 姜鸿 范英兰 靖博宇 陶弘武 《中华中医药学刊》 北大核心 2026年第1期30-33,I0007,共5页
目的提高并完善米泔水质量标准,以保证米泔水炮制中药饮片的质量稳定。方法增加了米泔水澄清度及pH值测定;采用TLC法,以L-赖氨酸为对照品,对米泔水进行薄层定性鉴别;建立紫外分光光度法测定米泔水中总氨基酸含量及酶活力。结果10批米泔... 目的提高并完善米泔水质量标准,以保证米泔水炮制中药饮片的质量稳定。方法增加了米泔水澄清度及pH值测定;采用TLC法,以L-赖氨酸为对照品,对米泔水进行薄层定性鉴别;建立紫外分光光度法测定米泔水中总氨基酸含量及酶活力。结果10批米泔水浊度值为2.280~3.412;pH值在6.14~6.58;薄层定性鉴别斑点清晰;总氨基酸在5.31~53.1μg(r=0.9990)范围内线性关系良好,加样回收率97.54%~100.1%(RSD=0.9%);总氨基酸含量在1.19~1.47 mg·mL^(-1),酶活力在5.42~6.37 U·L^(-1)。结论提高并完善了米泔水的质量控制方法,方法准确稳定,重复性好,可用于米泔水的质量控制。 展开更多
关键词 米泔水 质量标准 L-赖氨酸 总氨基酸 酶活力
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近红外光谱技术快速检测烟草花中主要活性成分含量的研究
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作者 付秋娟 许明磊 +6 位作者 张忠锋 黄择祥 谭效磊 侯小东 韩晓 孙婷婷 孟凡超 《中国烟草科学》 北大核心 2026年第1期116-123,共8页
为了实现对烟草花中主要活性成分(还原糖、总黄酮、绿原酸、芸香苷和西柏三烯二醇)的快速无损检测,以全国196份不同产地、不同品种的烟草花为研究对象,采用近红外光谱技术建立了5种活性成分的分析模型。通过筛选光谱预处理方法,优化谱... 为了实现对烟草花中主要活性成分(还原糖、总黄酮、绿原酸、芸香苷和西柏三烯二醇)的快速无损检测,以全国196份不同产地、不同品种的烟草花为研究对象,采用近红外光谱技术建立了5种活性成分的分析模型。通过筛选光谱预处理方法,优化谱区范围和主成分数,进一步提升了模型性能。利用内部交叉验证,得到了各成分的最优模型。结果表明:还原糖、总黄酮、绿原酸、芸香苷和西柏三烯二醇5种活性成分的近红外校正模型中,校正集相关系数(R_(c))为0.957~0.986,校正均方根误差(RMSEC)为0.025%~0.995%;交叉验证相关系数(R_(cv))为0.901~0.979,交叉验证均方根误差(RMSECV)为0.030%~1.350%。外部验证结果显示,5种活性成分模型的相对标准偏差(RSD)均小于10%,且t检验表明,近红外光谱法预测值与传统化学分析值之间无显著差异。这表明该方法具有较高的准确性和可靠性,能够快速无损地检测烟草花中5种主要活性成分,为烟草花的高效开发利用提供了技术支撑。 展开更多
关键词 烟草花 近红外 还原糖 总黄酮 绿原酸 芸香苷 西柏三烯二醇
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Changes of Petroleum Acid Distribution Characterized by FT-ICR MS in Heavy Acidic Crude Oil after True Boiling Point Distillation 被引量:8
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作者 Liu Yingrong Zhang Qundan +3 位作者 Wang Wei Liu Zelong Zhu Xinyi Tian Songbai 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2014年第1期8-12,共5页
The molecular transformations of carboxylic acids in heavy acidic SL crude before and after true boiling point distillation were examined by ultra-high resolution negative-ion electrospray ionization(ESI) Fourier tran... The molecular transformations of carboxylic acids in heavy acidic SL crude before and after true boiling point distillation were examined by ultra-high resolution negative-ion electrospray ionization(ESI) Fourier transform ion cyclotron resonance mass spectrometry(FT-ICR MS). The acid class(heteroatom number), type(z numbers) and carbon number distributions were positively characterized. It was found out that the total acid number(TAN) of SL crude decreased after true boiling point distillation, and the abundance of O2 class in mass spectra was also found to be reduced from 67.6% to 34.5% in SL TBP mixed crude as measured by MS spectra, indicating to a potential carboxylic acid decomposition. However, it was interesting that the carboxylic acids type distribution in both oils was almost the same although their relative abundance in SL TBP mixed crude turned to be much lower, suggesting that various petroleum carboxylic acid types have the similar thermal decomposition reaction behavior. Furthermore, for each O2 type of acids in SL TBP mixed crude, the abundance of carboxylic acids with carbon number higher than 35 was reduced greatly, especially for those with carbon number higher than 60, the mass peaks of which were nearly totally removed, indicating that the large carboxylic acid molecules in heavy fractions decomposed more significantly because of longer heating time during the true boiling point distillation process. As a result, the reduction of TAN may be caused by the thermal decomposition of carboxylic acids especially those with high carbon number, suggesting that quick distillation or much lower pressure is required to avoid the thermal decomposition. 展开更多
关键词 true boiling point distillation carboxylic acid ESI FT-ICR MS acidic crude total acid number(TAN)
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低共熔溶剂法提取九牛草总酚酸及其眼刺激性和抗氧化活性研究
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作者 胡思齐 蒋青香 +3 位作者 钟民勇 刘剑 刘红芹 李慧 《化学与生物工程》 北大核心 2026年第3期50-56,共7页
通过单因素和正交实验优化了九牛草总酚酸的低共熔溶剂(DESs)提取工艺,并对提取的九牛草总酚酸的眼刺激性和体外抗氧化活性进行了评价。结果表明,在DESs-4(甜菜碱-尿素,物质的量比1∶2)为提取溶剂、DESs-4含水率为50%、料液比为1∶20(g... 通过单因素和正交实验优化了九牛草总酚酸的低共熔溶剂(DESs)提取工艺,并对提取的九牛草总酚酸的眼刺激性和体外抗氧化活性进行了评价。结果表明,在DESs-4(甜菜碱-尿素,物质的量比1∶2)为提取溶剂、DESs-4含水率为50%、料液比为1∶20(g∶mL)、提取时间为150 min的条件下,总酚酸提取量为91.7 mg·g^(-1),相较于提取溶剂水(50.0 mg·g^(-1))和30%乙醇(60.0 mg·g^(-1))分别提高了83%和53%;当九牛草总酚酸浓度低于10 mg·mL^(-1)时,无眼刺激性;在测试浓度范围内,九牛草总酚酸清除DPPH自由基、ABTS自由基的IC_(50)值分别为0.920、0.158 mg·mL^(-1)。提供了一种简单、高效的九牛草总酚酸提取工艺,在保证较高总酚酸提取量的同时保留了其生物活性,为九牛草资源的开发利用提供了理论基础。 展开更多
关键词 低共熔溶剂 九牛草 总酚酸 抗氧化活性
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牛膝总皂苷提取物对自发性高血压大鼠血管内皮功能损伤的改善作用及机制研究
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作者 梁瑞峰 葛文静 +4 位作者 寇晓波 田萍 安鸿志 魏征 张明利 《中国药房》 北大核心 2026年第3期331-337,共7页
目的 基于细胞色素P450 4A(CYP4A)/20-羟-二十烷四烯酸/(20-HETE)/G蛋白偶联受体75(GPR75)轴探究牛膝总皂苷(ABS)提取物对自发性高血压大鼠(SHR)血管内皮功能损伤的改善作用及机制。方法 将10只Wistar-Kyoto大鼠设为正常对照组;将40只SH... 目的 基于细胞色素P450 4A(CYP4A)/20-羟-二十烷四烯酸/(20-HETE)/G蛋白偶联受体75(GPR75)轴探究牛膝总皂苷(ABS)提取物对自发性高血压大鼠(SHR)血管内皮功能损伤的改善作用及机制。方法 将10只Wistar-Kyoto大鼠设为正常对照组;将40只SHR根据收缩压进行分层后,按随机数字表法分为模型组(MOD组)、卡托普利阳性对照组(CAP组,10 mg/kg)和ABS提取物低、高剂量组(ABS-L、ABS-H组,60、120 mg/kg),每组10只。各组动物灌胃相应药物或等体积纯水,每天1次,连续28 d。末次给药后,测量大鼠收缩压,检测血清中血管活性物质、炎症因子和氧化应激指标水平,观察大鼠胸主动脉病理形态学变化,检测胸主动脉组织中活性氧(ROS)水平及内皮型一氧化氮合酶(eNOS)、CYP4A、GPR75、核因子-κB p65(NF-κB p65)、磷酸化NF-κB p65、p22phox、还原型烟酰胺腺嘌呤二核苷酸磷酸氧化酶4(NOX4)的表达。结果 给药28 d后,与MOD组比较,ABS-L、ABS-H组大鼠收缩压及血清中20-HETE、血管紧张素II、内皮素1、白细胞介素1β、白细胞介素6、肿瘤坏死因子α、细胞间黏附分子1和丙二醛水平均显著降低(P<0.05或P<0.01);一氧化氮、超氧化物歧化酶、谷胱甘肽过氧化物酶和过氧化氢酶水平均显著升高(P<0.05或P<0.01);胸主动脉内膜损伤减轻,内皮细胞形态改善;胸主动脉中ROS、CYP4A、GPR75、p22phox和NOX4的表达及NF-κB p65蛋白的磷酸化水平均显著下调/降低(P<0.05或P<0.01),eNOS的表达均显著上调(P<0.05或P<0.01)。结论 ABS提取物可能通过下调CYP4A表达,减少20-HETE生成,抑制GPR75激活,进而抑制下游NF-κB和NOX4的活化,有效减轻SHR的炎症反应和氧化应激,从而改善其高血压相关血管内皮功能损伤。 展开更多
关键词 牛膝总皂苷提取物 高血压 血管内皮功能损伤 20-羟-二十烷四烯酸 细胞色素P4504A
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酸性氧化电位水对鸡蛋的清洗除菌效果研究
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作者 赵向华 夏树立 +4 位作者 吴鹏飞 韩静 夏毅 李晓红 于海涛 《家禽科学》 2026年第2期12-19,共8页
本研究旨在探究不同浓度酸性氧化电位水清洗鸡蛋对蛋壳及蛋液中沙门氏菌、大肠杆菌、菌落总数及蛋品质的影响,为其在鸡蛋清洗除菌领域的规模化应用提供试验依据。试验选取同一品种、同一批次健康蛋鸡新产蛋15 000枚,随机分为5组(每组3... 本研究旨在探究不同浓度酸性氧化电位水清洗鸡蛋对蛋壳及蛋液中沙门氏菌、大肠杆菌、菌落总数及蛋品质的影响,为其在鸡蛋清洗除菌领域的规模化应用提供试验依据。试验选取同一品种、同一批次健康蛋鸡新产蛋15 000枚,随机分为5组(每组3个重复,每重复1 000枚):对照组为未清洗组,试验1组使用自来水清洗,试验2~4组分别采用1:1、1:5、1:10比例稀释的酸性氧化电位水清洗。结果显示:1:1、1:5浓度组对蛋壳及蛋内微生物的抑菌效果最佳,测试期内可维持大肠杆菌及菌落总数含量<1 CFU/mL;蛋品质横向比较,试验第14天,1:10浓度组蛋白高度、哈氏单位显著高于自来水组;纵向对比可见,随放置时间延长,各组蛋白高度、哈氏单位均显著性下降,其中1:1浓度组降幅最小,可有效延缓鸡蛋新鲜度下降。 展开更多
关键词 酸性氧化电位水 鸡蛋 沙门氏菌 大肠杆菌 菌落总数 蛋品质
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Review and Comprehensive Analysis of Composition and Origin of High Acidity Crude Oils 被引量:1
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作者 Cai Xinheng Tian Songbai 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2011年第1期6-15,共10页
High acidity crude oils have an advantage over normal oils in terms of their price,but can cause corrosion and refinery problems.They are the so-called opportunity crudes and likely to be important reserved resources ... High acidity crude oils have an advantage over normal oils in terms of their price,but can cause corrosion and refinery problems.They are the so-called opportunity crudes and likely to be important reserved resources in the 21st century.Researches on high acidity crude oils are becoming more and more profound.Based on the existing research achievements,this article has given an overview of the chemical composition and acid distribution of high acidity oils,and also analyzed their origin types and potential influence factors. 展开更多
关键词 high acidity oils total acid number acid composition ORIGIN influence factors
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浓香型成品酒货架期物质变化探究
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作者 张燕 彭礼群 +3 位作者 张建 肖宇航 罗明有 罗陟 《酿酒》 2026年第2期66-70,共5页
本研究监测了浓香型成品酒在2年货架期内的总酸、总酯及己酸乙酯的含量变化,重点分析储存1年后“酸酯总量”与“己酸+己酸乙酯”指标的稳定性及新国标(GB/T 10781—2021)的符合性。结果显示:货架期内酒体呈“酸增酯减”趋势,且初始总酸... 本研究监测了浓香型成品酒在2年货架期内的总酸、总酯及己酸乙酯的含量变化,重点分析储存1年后“酸酯总量”与“己酸+己酸乙酯”指标的稳定性及新国标(GB/T 10781—2021)的符合性。结果显示:货架期内酒体呈“酸增酯减”趋势,且初始总酸含量较高的酒样酯类水解速率相对较缓;储存1年后,各酒样的复合指标变异系数均低于2.0%,稳定性良好,且均符合新国标优级标准,本研究为浓香型白酒货架期品质调控提供了理论依据。 展开更多
关键词 浓香型白酒 货架期 总酸 总酯 己酸乙酯 复合指标
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Cold Acclimation-Induced Changes in Total Soluble Protein, RNA, DNA, RNase and Freezing Resistance in Populus tomentosa Cuttings 被引量:3
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作者 林善枝 张志毅 《Forestry Studies in China》 CAS 2002年第2期9-15,共7页
The changes in the contents of total soluble protein and RNA, the activity of RNase in leaves and branches of Populus tomentosa cuttings at various periods (viz: cold acclimation, deacclimation, chilling stress an... The changes in the contents of total soluble protein and RNA, the activity of RNase in leaves and branches of Populus tomentosa cuttings at various periods (viz: cold acclimation, deacclimation, chilling stress and the recovery after chilling stress), and the survival rate and the freezing resistance of cuttings during cold acclimation at -3℃ were investigated. Results showed that cold acclimation not only increased the contents of total soluble protein and RNA, the survival rates and the freezing resistance of cuttings, decreased the activity of RNase, but also reduced the declining degree of total soluble protein and RNA contents, and the increasing level of RNase caused by chilling stress as compared with the controls. In addition, cold acclimation augmented the increase in the level of total soluble protein and RNA, and facilitated the decrease of RNase during the recovery periods. Further analysis found that the DNA content of all treatments kept relative stability at various periods. The changes in total soluble protein, RNA and RNase were closely related to the freezing resistance of cuttings. It appears that the increase of RNA content caused by cold acclimation induced decrease of RNase activity may be involved in the accumulation of total soluble protein and the induction of freezing resistance of cuttings. 展开更多
关键词 Populus tomentosa cold acclimation freezing resistance total soluble protein nucleic acid
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银杏叶茶主要成分含量测定及抗氧化、抗炎活性分析
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作者 邓慧聪 柳娟 +2 位作者 冯宝民 卢轩 马逍遥 《食品研究与开发》 2026年第6期63-70,共8页
该文以银杏叶茶为研究对象,建立银杏叶茶中总黄酮、总萜类内酯及总酚酸含量测定方法,并比较其沸水浸泡提取物的体外抗氧化和抗炎活性。采用紫外-可见分光光度法测定银杏叶茶中总黄酮含量,利用高效液相色谱法(high performance liquid ch... 该文以银杏叶茶为研究对象,建立银杏叶茶中总黄酮、总萜类内酯及总酚酸含量测定方法,并比较其沸水浸泡提取物的体外抗氧化和抗炎活性。采用紫外-可见分光光度法测定银杏叶茶中总黄酮含量,利用高效液相色谱法(high performance liquid chromatography,HPLC)测定银杏叶茶中总萜类内酯和总酚酸含量。利用自由基清除试验评估银杏叶茶沸水浸泡提取物的抗氧化活性,通过检测银杏叶茶沸水浸泡提取物对脂多糖(lipopolysaccharide,LPS)诱导细胞释放炎症介质一氧化氮的抑制能力,评估银杏叶茶提取物的抗炎作用。结果显示,银杏叶茶中总黄酮和总萜类内酯含量最高分别可达(37.583±0.003) mg/g和(52.153±0.061) mg/g,而总酚酸含量为(24.831±0.004) mg/g,该含量测定方法简便易行,结果准确。生物活性分析显示,银杏叶茶沸水提取物具有抗氧化能力和抗炎活性。 展开更多
关键词 银杏叶茶 含量测定 总黄酮 总萜类内酯 总酚酸 抗氧化活性 抗炎活性
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酱香型鲜白酒糟的液态菌酶协同发酵工艺优化及发酵酱香型鲜白酒糟在生长猪上的营养价值评定
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作者 周紫筠 黎美宏 +4 位作者 张焜 周艺璇 车炼强 虞洁 吴彩梅 《动物营养学报》 北大核心 2026年第2期1410-1430,共21页
本试验旨在优化酱香型鲜白酒糟的液态菌酶协同发酵工艺,评定发酵酱香型鲜白酒糟在生长猪上的营养价值,为酱香型鲜白酒糟在生长猪饲粮的利用提供参考。采用单因素试验,选取初始pH、发酵时间、水料比、菌酶添加量和发酵温度5个主要考察因... 本试验旨在优化酱香型鲜白酒糟的液态菌酶协同发酵工艺,评定发酵酱香型鲜白酒糟在生长猪上的营养价值,为酱香型鲜白酒糟在生长猪饲粮的利用提供参考。采用单因素试验,选取初始pH、发酵时间、水料比、菌酶添加量和发酵温度5个主要考察因素来考察发酵对半纤维素、总糖和总酸含量的影响;基于单因素试验结果,以半纤维素含量为响应值,采用响应面试验优化酱香型鲜白酒糟的发酵工艺参数。通过养分含量测定、扫描电镜观察、红外光谱分析和微生物16S测序分析液态菌酶发酵前后酱香型鲜白酒糟的品质变化,通过测定生长猪的氨基酸回肠消化率、养分全肠道消化率(TTD)、消化能和代谢能,评价其对生长猪的营养价值。结果表明:1)以半纤维素含量为响应值的最佳发酵工艺为初始pH 5.7,发酵时间28 h,水料比1.8,菌酶添加量0.3%,发酵温度43.7℃;2)与未发酵的酱香型鲜白酒糟相比,发酵酱香型鲜白酒糟的粗蛋白质含量显著升高了10.74%(P<0.05),粗纤维含量显著降低了21.02%(P<0.05);发酵酱香型鲜白酒糟表面粗糙且孔隙增加,纤维结构部分分解,蛋白质二级结构向α-螺旋结构转变,微生物组成主要以肠球菌属(62%)和梭状芽孢杆菌属(25%)为主;3)与未发酵的酱香型鲜白酒糟相比,发酵酱香型鲜白酒糟中除胱氨酸外的其余17种氨基酸的标准回肠消化率均显著提高(P<0.05);4)与添加未发酵的酱香型鲜白酒糟试验饲粮相比,添加发酵酱香型鲜白酒糟试验饲粮的粗蛋白质、粗纤维和粗灰分的TTD均显著提高(P<0.05),消化能和代谢能差异不显著(P>0.05)。综上所述,液态菌酶协同发酵有效改善了酱香型鲜白酒糟的营养品质和对生长猪的营养价值。 展开更多
关键词 酱香型鲜白酒糟 菌酶协同 液态发酵 发酵工艺 氨基酸回肠消化率 全肠道消化率 消化能 代谢能
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