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Effects of β-Amino Butyric Acid Induced Rice Blast Resistance on Reactive Oxygen Metabolism 被引量:5
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作者 李莉 郭晓丽 +5 位作者 刘晓梅 温嘉伟 张秀容 孙辉 赵宇 任金平 《Agricultural Science & Technology》 CAS 2009年第3期112-114,共3页
[Objective] This study was to understand the effects of β-Amino butyric acid(abbreviated as BABA) induced rice blast resistance on reactive oxygen metabolism. [Method] Using the cultivar Chaochan 2 that is highly sus... [Objective] This study was to understand the effects of β-Amino butyric acid(abbreviated as BABA) induced rice blast resistance on reactive oxygen metabolism. [Method] Using the cultivar Chaochan 2 that is highly susceptible to disease as experimental material, the changes of catalase(CAT), and superoxide dismutase(SOD) and MDA activities in rice treated by BABA were investigated. [Result] In rice plants treated by BABA, the activities of CAT and SOD increased, meanwhile the MDA content also rose to some extent, resulting in the disease resistance to rice blast. [Conclusion] By influencing reactive oxygen metabolism, BABA endows rice plants with resistance to rice blast. BABA is safe to environment and has highly resistance-inducing capacity, it could be generalized in production. 展开更多
关键词 β-amino butyric acid Rice blast Induced resistance
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脂肪乳氨基酸(17)葡萄糖(11%)注射液稳定性研究
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作者 杨培培 张丽雯 +1 位作者 程钢 黄赵刚 《中国药业》 CAS 2024年第2期60-62,共3页
目的为临床合理使用脂肪乳氨基酸(17)葡萄糖(11%)注射液(商品名卡文)提供依据。方法将卡文3个腔室液体混匀(样品S1);再分别添加电解质(氯化钾和氯化钠,样品S2),维生素(水溶性维生素及脂溶性维生素,样品S3),多种微量元素(样品S4),以及上... 目的为临床合理使用脂肪乳氨基酸(17)葡萄糖(11%)注射液(商品名卡文)提供依据。方法将卡文3个腔室液体混匀(样品S1);再分别添加电解质(氯化钾和氯化钠,样品S2),维生素(水溶性维生素及脂溶性维生素,样品S3),多种微量元素(样品S4),以及上述所有成分(样品S5)。分别于室温下放置0,4,8,12 h时测定混合液的pH、渗透压、不溶性微粒数,并考察乳剂粒径分布情况。结果样品S1-S5室温下放置12 h内外观无明显变化,pH为5.51~5.59;渗透压,S2为934~972 mOsmol/kg,S3为816~831 mOsmol/kg,S4为810~835 mOsmol/kg,S5为934~957 mOsmol/kg;不溶性微粒变化不明显;乳剂粒径分布集中在1~10 nm。结论在卡文中添加规定限度内的电解质、维生素和多种微量元素,对其pH、不溶性微粒、乳剂粒径等影响较小,但电解质对渗透压影响较大,应予以重视。 展开更多
关键词 脂肪乳氨基酸(17)葡萄糖(11%)注射液 电解质 维生素 配伍 稳定性
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克罗恩病患者血清CCL11及I-FABP的表达水平与疾病活动指数的相关性研究
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作者 杨晓英 窦维嘉 庞秀峰 《海南医学》 CAS 2024年第12期1685-1689,共5页
目的探究克罗恩病(CD)患者血清嗜酸性粒细胞趋化因子(CCL11)及肠脂肪酸结合蛋白(I-FABP)水平表达与疾病活动指数的相关性。方法选取2021年2月至2023年2月于上海市杨浦区中心医院就诊的98例CD患者进行研究(CD组),根据疾病活动指数(CDAI)... 目的探究克罗恩病(CD)患者血清嗜酸性粒细胞趋化因子(CCL11)及肠脂肪酸结合蛋白(I-FABP)水平表达与疾病活动指数的相关性。方法选取2021年2月至2023年2月于上海市杨浦区中心医院就诊的98例CD患者进行研究(CD组),根据疾病活动指数(CDAI)评分将患者分为缓解期21例、轻度活动期31例、中度活动期28例和重度活动期18例,另选取同期健康者100例作为对照组,采用酶联免疫吸附法检测血清CCL11、I-FABP水平,采用Spearman法分析血清CCL11、I-FABP水平与CDAI评分的相关性,采用受试者工作特征曲线(ROC)分析血清CCL11、I-FABP水平对CD患者疾病活动度的评估价值。结果CD组患者的血清CCL11、I-FABP水平分别为(51.33±7.14)pg/mL、(64.85±11.56)ng/mL,明显高于对照组的(28.56±6.61)pg/mL、(31.38±10.35)ng/mL,差异均有统计学意义(P<0.05);缓解期、轻度、中度、重度活动期CD患者血清CCL11水平分别为(31.47±7.02)pg/mL、(45.52±7.08)pg/mL、(57.83±7.12)pg/mL、(74.41±7.43)pg/mL,I-FABP水平分别为(48.13±10.79)ng/mL、(59.97±11.32)ng/mL、(70.76±11.75)ng/mL、(83.58±12.58)ng/mL,缓解期、轻度活动期、中度活动期、重度活动期CD患者血清CCL11、I-FABP水平依次升高,差异均有统计学意义(P<0.05)。Spearman相关性分析结果显示,血清CCL11、I-FABP水平均与CDAI评分呈正相关(r=0.834、0.620,P<0.01);ROC分析结果显示,血清CCL11、I-FABP水平评估CD患者疾病活动度的AUC分别为0.882、0.889,敏感性为81.82%、80.52%,特异性为85.71%、85.71%。两者联合评估疾病活动度的AUC为0.938,显著高于单项检测(P<0.05),联合检测的敏感性和特异性为93.51%、85.71%。结论CD患者血清CCL11、I-FABP水平升高,与疾病活动指数密切相关,且两者联合评估CD患者疾病活动度具有较高效能。 展开更多
关键词 克罗恩病 嗜酸性粒细胞趋化因子 肠脂肪酸结合蛋白 疾病活动指数 相关性
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Acetyl-11-keto-β-boswellic acid extracted from Boswellia serrata promotes Schwann cell proliferation and sciatic nerve function recovery 被引量:5
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作者 xiao-wen jiang bin-qing zhang +3 位作者 lu qiao lin liu xue-wei wang wen-hui yu 《Neural Regeneration Research》 SCIE CAS CSCD 2018年第3期484-491,共8页
Frankincense can promote blood circulation. Acetyl-11-keto-β-boswellic acid (AKBA) is a small molecule with anti-inflammatory properties that is derived from Boswellia serrata. Here, we hypothesized that it may pro... Frankincense can promote blood circulation. Acetyl-11-keto-β-boswellic acid (AKBA) is a small molecule with anti-inflammatory properties that is derived from Boswellia serrata. Here, we hypothesized that it may promote regeneration of injured sciatic nerve. To address this hypothesis, we established a rat model of sciatic nerve injury using a nerve clamping method. Rats were administered AKBA once every 2 days at doses of 1.5, 3, and 6 mg/kg by intraperitoneal injection for 30 days from the 1st day after injury. Sciatic nerve function was evaluated using the sciatic functional index. Degree of muscle atrophy was measured using the triceps surae muscle Cuadros index.Neuropathological changes were observed by hematoxylin-eosin staining. Western blot analysis was used to detect expression of phospho-extracellular signal-regulated kinase 1 and 2 (p-ERK1/2) in injured nerve. S100 immunoreactivity in injured nerve was detected by immunohistochemistry. In vivo experiments showed that 3 and 6 mg/kg AKBA significantly increased sciatic nerve index, Cuadros index of triceps muscle, p-ERK1/2 expression, and S100 immunoreactivity in injured sciatic nerve of sciatic nerve injury model rats. Furthermore,for in vitro experiments, Schwann cells were treated with AKBA at 0–20 μg/mL. Proliferation of Schwann cells was detected by Cell Counting Kit-8 colorimetry assay. The results showed that 2 μg/mL AKBA is the optimal therapeutic concentration. In addition, ERK phosphorylation levels increased following 2 μg/mL AKBA treatment. In the presence of the ERK1/2 inhibitor, PD98059 (2.5 μL/mL), the AKBA-induced increase in p-ERK1/2 protein expression was partially abrogated. In conclusion, our study shows that AKBA promotes peripheral nerve regeneration with ERK protein phosphorylation playing a key role in this process. 展开更多
关键词 nerve regeneration acetyl-11-keto-β-boswellic acid peripheral nerve injury repair sciatic nerve crush injury Schwann cells cell proliferation ERK signaling pathway PD98059 neural regeneration
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UV-Vis Spectroscopy Study on Interaction between Microperoxidase-11 and Pr Ion Under Acid Rain Stress 被引量:2
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作者 吉红念 黄晓华 +1 位作者 周青 陆天虹 《Journal of Rare Earths》 SCIE EI CAS CSCD 2002年第5期541-546,共6页
Interaction between rare earth ion praseodymium (Pr(Ⅲ)) and MP11 with/without hydrogen ion (H +) in different media( aqueous, phosphate buffer, physiological condition) were studied by UV Vis spectroscopy. All the ... Interaction between rare earth ion praseodymium (Pr(Ⅲ)) and MP11 with/without hydrogen ion (H +) in different media( aqueous, phosphate buffer, physiological condition) were studied by UV Vis spectroscopy. All the results indicate that Pr(Ⅲ) interacts with MP11, increasing the non planarity of porphyrin periphery, leading MP11 to form two conformations when titrated by Pr(Ⅲ). Excessive Pr(Ⅲ) acts as a contaminant in living organism. H + and Pr(Ⅲ) have antagonistic effect on MP11, suggesting that at suitable concentration under physiological conditions, Pr(Ⅲ) can be used as biomodulator in protecting plants from acid rain stress or in rehabilitating the harm. 展开更多
关键词 rare earths PRASEODYMIUM MICROPEROXIDASE-11 UV-Vis spectroscopy acid rain stress antagonistic effect
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Acetyl-11-keto-β-boswellic acid inhibits proliferation and induces apoptosis of gastric cancer cells through the phosphatase and tensin homolog/Akt/cyclooxygenase-2 signaling pathway 被引量:5
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作者 Meng-Xue Sun Xiao-Pu He +4 位作者 Pei-Yun Huang Qi Qi Wei-Hao Sun Gao-Shuang Liu Jie Hua 《World Journal of Gastroenterology》 SCIE CAS 2020年第38期5822-5835,共14页
BACKGROUND Gastric cancer is one of the most common malignant tumors of the digestive system worldwide,posing a serious danger to human health.Cyclooxygenase(COX)-2 plays an important role in the carcinogenesis and pr... BACKGROUND Gastric cancer is one of the most common malignant tumors of the digestive system worldwide,posing a serious danger to human health.Cyclooxygenase(COX)-2 plays an important role in the carcinogenesis and progression of gastric cancer.Acetyl-11-keto-β-boswellic acid(AKBA)is a promising drug for cancer therapy,but its effects and mechanism of action on human gastric cancer remain unclear.AIM To evaluate whether the phosphatase and tensin homolog(PTEN)/Akt/COX-2 signaling pathway is involved in the anti-tumor effect of AKBA in gastric cancer.METHODS Human poorly differentiated BGC823 and moderately differentiated SGC7901 gastric cancer cells were routinely cultured in Roswell Park Memorial Institute 1640 medium supplemented with 10%fetal bovine serum and 1%penicillin/streptomycin.Gastric cancer cell proliferation was determined by methyl thiazolyl tetrazolium colorimetric assay.Apoptosis was measured by flow cytometry.Cell migration was assessed using the wound-healing assay.Expression of Bcl-2,Bax,proliferating cell nuclear antigen,PTEN,p-Akt,and COX-2 were detected by Western blot analysis.A xenograft nude mouse model of human gastric cancer was established to evaluate the anti-cancer effect of AKBA RESULTS AKBA significantly inhibited the proliferation of gastric cancer cells in a dose-and time-dependent manner,inhibited migration in a time-dependent manner,and induced apoptosis in a dose-dependent manner in vitro;it also inhibited tumor growth in vivo.AKBA up-regulated the expression of PTEN and Bax,and downregulated the expression of proliferating cell nuclear antigen,Bcl-2,p-Akt,and COX-2 in a dose-dependent manner.The PTEN inhibitor bpv(Hopic)reversed the high expression of PTEN and low expression of p-Akt and COX-2 that were induced by AKBA.The Akt inhibitor MK2206 combined with AKBA downregulated the expression of p-Akt and COX-2,and the combined effect was better than that of AKBA alone.CONCLUSION AKBA inhibits the proliferation and migration and promotes the apoptosis of gastric cancer cells through the PTEN/Akt/COX-2 signaling pathway. 展开更多
关键词 Acetyl-11-keto-β-boswellic acid Gastric cancer Cell proliferation APOPTOSIS CYCLOOXYGENASE-2 Tumor xenograft
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Syntheses and Structural Characterization of Dimethyltin Complexs of N-(3-Methoxysalicylidene)-α-amino Acid 被引量:3
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作者 党艳秋 杨红军 田来进 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2012年第4期479-484,共6页
Three new dimethyltin complexes of N-(3-methoxysalicylidene)-α-amino acid,(CH3)2Sn(3-CH3O-2-OC6H3CH=NCHRCOO)(R = H,1;CH3,2;(CH3)2CH,3),have been synthe-sized by treating dimethyltin dichloride with the pota... Three new dimethyltin complexes of N-(3-methoxysalicylidene)-α-amino acid,(CH3)2Sn(3-CH3O-2-OC6H3CH=NCHRCOO)(R = H,1;CH3,2;(CH3)2CH,3),have been synthe-sized by treating dimethyltin dichloride with the potassium salt of the ligand and characterized by elemental analysis,IR and 1H NMR spectra.The crystal structure of [(CH3)2Sn(3-CH3O-2-OC6H3CH=NCH2COO)(CH3OH)]2 H2O(1a),formed from methanol solution of 1,has been deter-mined.The crystal belongs to the monoclinic system,space group C/2c with a = 20.636(3),b = 7.8854(9),c = 20.668(2) ,β= 113.265(2)°,V = 3089.7(6) 3,Z = 4,Dc = 1.707 g/cm3,= 1.675 mm-1,F(000) = 1592,R = 0.0301 and wR = 0.0841.In complex 1a,the tin atom is six-coordinate and possesses a distorted [SnC2NO3] octahedral geometry with the two methyl groups occupying the trans positions.The weak Sn O interactions and intermolecular hydrogen bonds connected the molecules into an infinite chain. 展开更多
关键词 organotin complex N-(3-methoxysalicyliden)-α-amino acid crystal structure
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A practical synthesis of trifluorophenyl R-amino acid:The key precursor for the new anti-diabetic drug sitagliptin 被引量:1
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作者 Li Li Zeng Ying Jie Ding +2 位作者 Gui Cheng Zhang Hong Rui Song Wen Hui Hu 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第12期1397-1399,共3页
Sitagliptin is the first new anti-diabetic drug in DPP-Ⅳ inhibitor class. The general synthesis of sitagliptin is by coupling of the β-amino acid fragment with the heterocycle fragment. Though the specific β-amino ... Sitagliptin is the first new anti-diabetic drug in DPP-Ⅳ inhibitor class. The general synthesis of sitagliptin is by coupling of the β-amino acid fragment with the heterocycle fragment. Though the specific β-amino acid can be easily made from the corresponding R-amino acid by Arndt-Eistert hornologation, the optically pure precursor R-amino acid is difficult to prepare. We herein reported a practical protocol to make the trifluorophenyl substituted R-amino acid 4 in 〉99.9% ee and 40.3% yield by the enzymatic resolution employing enantioselective hydrolysis and a general separation procedure. This protocol requires only cheap starting materials and friendly reaction condition. The procedure not only allows people to prepare the drug substance, but also provides an alternative method for prepareing the rare α-amino acid and the subsequent β-amino acid. 展开更多
关键词 SITAGLIPTIN β-amino acid DPP-Ⅳ inhibitor Practical synthesis
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EFFECT OF CIS-9, TRANS-11-CONJUGATED LINOLEIC ACID ON CELL CYCLE OF MAMMARY ADENOCARCINOMA CELLS(MCF-7) 被引量:1
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作者 刘家仁 陈炳卿 +3 位作者 韩晓辉 杨艳梅 郑玉梅 刘瑞海 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2002年第2期93-99,共7页
Objective: To determine the effect of cis-9, trans-1 1-conjugated linoleic acid on the cell cycle of mammary cancer cells (MCF-7) and the possible mechanism of the inhibitory effect of c9,t11-CLA. Methods: Using cell ... Objective: To determine the effect of cis-9, trans-1 1-conjugated linoleic acid on the cell cycle of mammary cancer cells (MCF-7) and the possible mechanism of the inhibitory effect of c9,t11-CLA. Methods: Using cell culture and immunocytochemical techniques, we examined the cell growth, DNA synthesis, expression of PCNA, cyclin A, B1, D1, p16ink4a and p21cip/waf1 of MCF-7 cells at various c9,t11-CLA concentrations (25μM, 50μM, 100μM and 200μM), at 24h and 48h. 96% ethand was used as negative control. Results: The cell growth and DNA synthesis of MCF-7 cells were inhibited by c9,t11-CLA. After treatment with various doses of c9,t11-CLA mentioned above for 8 days, the inhibition frequency was 27.18%, 35.43%, 91.05%, and 92.86%, respectively. Inhibitory effect of c9,t11-CLA on DNA synthesis (except for 25μM, 24h) was demonstrated by significantly less incorporation of 3H-TdR than the negative control (P<0.05 and P<0.01). To further investigate the influence of the cell cycle progression, we found that c9,t11-CLA may arrest the cell cycle of MCF-7 cells. Immunocytochemical staining demonstrated that incubation with different concentration of c9,t11-CLA at various times significantly decreased the expression of PCNA, Cyclin A, B1, D1 in MCF-7 cells compared to the negative control (P<0.01), whereas the expression of p16ink4a and p21cip/waf1, cyclin-dependent kinases inhibitors (CDKI), were increased. Conclusions: The cell growth and proliferation of MCF-7 cells is inhibited by c9,t11-CLA via blocking cell cycle, accompanying reduced expression of cyclin A, B1, D1 and enhanced expression of CDKI (p16ink4a and p21cip/waf1). 展开更多
关键词 Mammary adenocarcinoma cells (MCF-7) cis-9 trans-11-conjugated linoleic acid(c9 t11-CLA) IMMUNOCYTOCHEMISTRY Cell cycle Inhibition
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Evaluation of the Dietary Reference Intakes for Japanese (2010 Edition): Recommended Protein, Pantothenic acid, Vitamin D, and Iron Intakes for Breast-Fed Infants Aged 6 - 11 Months 被引量:1
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作者 Setsuko Tsutie Nobutaka Kurihara +3 位作者 Aki Sasaki Arisa Takagi Harumiti Seguti Tetsuya Inatome 《Food and Nutrition Sciences》 2011年第4期272-280,共9页
Objective: With regard to the 2010 edition of Dietary Reference Intakes for Japanese (DRIs-2010), we investigated whether the DRIs for two age groups, breast-fed infants aged 6-8 and 9-11 months, can be fulfilled for ... Objective: With regard to the 2010 edition of Dietary Reference Intakes for Japanese (DRIs-2010), we investigated whether the DRIs for two age groups, breast-fed infants aged 6-8 and 9-11 months, can be fulfilled for every nutrient in actual dietary practice. Design: We evaluated (1) whether the DRIs for all nutrients can be fulfilled in a formula with energy and protein exceeding their DRIs, (2) whether the DRIs for all nutrients can be fulfilled in a formula prepared in accordance with Japanese government-recommended weaning guidelines, and (3) what kinds of formulas can be prepared if the DRIs for all nutrients are fulfilled without referring to the weaning guidelines. Setting: Simulation of diet menu on the basis of published data in our university and survey of diet menu in a university hospital attached to a national medical school. Subjects: The three types of formulas were planned for ten days. Results: It was impossible to simultaneously fulfil the DRIs for 6 - 8-month-old infants concerning pantothenic acid, vitamin D, and iron and those for 9 - 11-month-old infants concerning these nutrients plus protein. Conclusion: According to the DRIs-2010, the DRI for all nutrients could not be fulfilled in an ingestible formula. 展开更多
关键词 Dietary Reference INTAKES Breast-Fed INFANTS (6 - 11-Month-Old) Pantothenic acid PROTEIN Vitamin D Iron
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Novel Method for Selective Debenzylation Under Maintenance of Fluoro Atom Substituted on β-Amino Acids
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作者 ZHENG Yi WU Gang +5 位作者 ZHU Xin-rong LI Yue-jie MA Yu-heng ZHAO Xin LU Tao ZHU Yong-qiang 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2011年第2期224-227,共4页
tert-Butyl (R)-3-amino-3-(3-fluorophenyl)propanoate(5) was prepared with conventional debenzylation method. However, the tert-butyl (R)-3-[(S)-1-phenylethyl-amino]-3-(3-fluorophenyl) propanoate(6) and te... tert-Butyl (R)-3-amino-3-(3-fluorophenyl)propanoate(5) was prepared with conventional debenzylation method. However, the tert-butyl (R)-3-[(S)-1-phenylethyl-amino]-3-(3-fluorophenyl) propanoate(6) and tert-butyl (R)-3-amino-3-phenylpropanoate(7) were generated as the byproducts under the general catalytic hydrogenation Pd(OH)2/C-H2 conditions. So a series of experiments was performed to optimize the reaction conditions so that product 5 could be obtained with high purity and yield. Finally an effective catalytic system, Pd/C-HCOOH-CH3OH, was discovered. 展开更多
关键词 β-amino acid DEBENZYLATION DEFLUORINATION Catalytic hydrogenation
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The design and synthesis of a novel organophosphorus compound containing the structure of both β-amino acid and β-aminophosphonate
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作者 Han Bing Teng 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第7期810-812,共3页
A novel organophosphorus compound containing the structure of bothβ-amino acid andβ-aminophosphonate is designed and synthesized.Arbuzov reaction with P(OEt)_3,the N-Boc protected iodide 3 cannot provide the desir... A novel organophosphorus compound containing the structure of bothβ-amino acid andβ-aminophosphonate is designed and synthesized.Arbuzov reaction with P(OEt)_3,the N-Boc protected iodide 3 cannot provide the desired product but 2-oxazolidinone 4 because of the neighboring-group participation of the Boc moiety.To avoid the intramolecular participation of the carbamates,the Ts protecting group is employed and the Ts-protected iodide 5 affords the target product successfully. 展开更多
关键词 β-amino acid β-aminophosphonate Neighboring-group participation Arbuzov reaction Amino-protecting group
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Synthesis and Structural Characterization of Some Diorganotin Complexes of N-(3,5-Dibromosalicylidene)-α-amino Acid and their Diphenyltin Dichloride Adducts
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作者 LaiJinTIAN ZhiCaiSHANG +1 位作者 XiJieLIU QingSenYU 《Chinese Chemical Letters》 SCIE CAS CSCD 2005年第2期193-196,共4页
The title complexes, R′2Sn(3,5-Br2-2-OC6H2CH=NCHRCOO), and their diphenyltindichloride adduct, R′2Sn(3,5-Br2-2-OC6H2CH=NCHRCOO)?SnPh2Cl2, were synthesized and char-acterized by elemental analysis, IR, H and C NMR an... The title complexes, R′2Sn(3,5-Br2-2-OC6H2CH=NCHRCOO), and their diphenyltindichloride adduct, R′2Sn(3,5-Br2-2-OC6H2CH=NCHRCOO)?SnPh2Cl2, were synthesized and char-acterized by elemental analysis, IR, H and C NMR and X-ray single crystal diffraction. The 1 13structural features of the compounds were described. 展开更多
关键词 Diorganotin complexes molecular adduct crystal structure α-amino acid Schiff base.
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Dietary <i>γ</i>-Aminobutyric Acid Shortens the Life Span of Stroke-Prone Spontaneously Hypertensive Rats
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作者 Nakamichi Watanabe Naomi Washio 《Food and Nutrition Sciences》 2011年第4期301-303,共3页
Dietary γ-amino butyric acid (GABA) has been suggested to decrease systolic blood pressure. This study aimed to ex-amine the effects of dietary GABA on the life span of stroke-prone spontaneously hypertensive rats (S... Dietary γ-amino butyric acid (GABA) has been suggested to decrease systolic blood pressure. This study aimed to ex-amine the effects of dietary GABA on the life span of stroke-prone spontaneously hypertensive rats (SHRSPs). In this study, life span was determined for SHRSPs provided 1% NaCl solution or 0.01% GABA in 1% NaCl solution as drinking water. The life span of the GABA-fed group (76.3 ± 1.65 days) was significantly shorter than that of the control group (81.6 ± 0.88 days). The results of this study may not be applicable to humans. Future studies will be necessary to elucidate the mechanism underlying this phenomenon. 展开更多
关键词 γ-amino Butyric acid Stroke-Prone Spontaneously HYPERTENSIVE Rat Life Span
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亚油酸含量对大豆11S球蛋白膜理化性质的影响
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作者 周荣雪 赵源 +2 位作者 石林凡 任中阳 翁武银 《食品科学》 EI CAS CSCD 北大核心 2024年第2期1-8,共8页
为探究成膜液和膜中脂质和蛋白之间的相互作用,研究了亚油酸含量(蛋白质量的0%、10%、20%、30%和40%)对11S球蛋白成膜液的黏度及膜的微观结构和理化性质的影响。共聚焦激光扫描显微镜图像显示,成膜液中油滴尺寸均随亚油酸含量增加而增大... 为探究成膜液和膜中脂质和蛋白之间的相互作用,研究了亚油酸含量(蛋白质量的0%、10%、20%、30%和40%)对11S球蛋白成膜液的黏度及膜的微观结构和理化性质的影响。共聚焦激光扫描显微镜图像显示,成膜液中油滴尺寸均随亚油酸含量增加而增大,干燥成膜后油滴尺寸进一步增大。扫描电子显微镜结果显示,添加亚油酸后光滑致密的蛋白膜上表面出现油滴聚集,而下表面变得粗糙,但未出现油滴。添加40%亚油酸后,膜的玻璃化转变温度、抗拉伸强度和水蒸气透过系数分别由53.50℃、12.67MPa和2.52×10^(-10)g/(m·Pa·s)降低至50.38℃、7.30 MPa和1.83×10^(-10)g/(m·Pa·s),而断裂延伸率由95.58%增加至198.15%。分子动力学模拟结果表明,11S球蛋白与亚油酸分子在200 ns内没有发生相互作用。添加亚油酸会导致11S球蛋白膜中离子键和二硫键比例下降,而疏水相互作用和非二硫键共价键比例增加。以上结果表明,添加亚油酸可以通过改变膜中蛋白间的化学相互作用,从而影响膜的理化性质。研究结果将为大豆蛋白乳液膜成膜机制的研究提供理论参考。 展开更多
关键词 11S球蛋白 可食膜 亚油酸 分子动力学模拟 化学结合力
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A Theoretical Study of <i>β</i>-Amino Acid Conformational Energies and Solvent Effect
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作者 Victor F. Waingeh Felix N. Ngassa Jie Song 《Open Journal of Physical Chemistry》 2015年第4期122-131,共10页
The conformations of four β-amino acids in a model peptide environment were investigated using Hartree-Fock (HF) and density functional theory (DFT) methods in gas phase and with solvation. Initial structures were ob... The conformations of four β-amino acids in a model peptide environment were investigated using Hartree-Fock (HF) and density functional theory (DFT) methods in gas phase and with solvation. Initial structures were obtained by varying dihedral angles in increments of 45° in the range 0° - 360°. Stable geometries were optimized at both levels of theory with the correlation consistent double-zeta basis set with polarization functions (cc-pVDZ). The results suggest that solvation generally stabilizes the conformations relative to the gas phase and that intramolecular hydrogen bonding may play an important role in the stability of the conformations. The β3 structures, in which the R-group of the amino acid is located on the carbon atom next to the N-terminus, are somewhat more stable relative to each other than the β2 structures which have the R-group on the carbon next to the carbonyl. 展开更多
关键词 Density Functional Theory β-amino acidS Conformational SEARCH
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STUDIES ON CHIRAL THIOPHOSPHORIC ACIDS AND THEIR DERIVATIVES 11.——THE RESOLUTION OF O-METHYL O-PHENYL THIOPHOSPHORIC ACID AND ABSOLUTE CONFIGURATIONS OF ITS OPTICAL ISOMERS
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作者 Chu Chi TANG, Mian Ji ZHANG, Fu Peng MA and Zhen LI Institute of Elemento-Organic Chemistry, Nankai University, Tianjin 300071 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第11期949-950,共2页
Racemic O-methyl O-pheayl thiophosphoric acid 1 has been successfully resolved through its quinine and brucine salts in methanol solution by fractional crystallization. The absolute configurations of the optically act... Racemic O-methyl O-pheayl thiophosphoric acid 1 has been successfully resolved through its quinine and brucine salts in methanol solution by fractional crystallization. The absolute configurations of the optically active 1 have been established as (+)-R-1 and (-)-S-1 by chemical correlation. 展开更多
关键词 acid STUDIES ON CHIRAL THIOPHOSPHORIC acidS AND THEIR DERIVATIVES 11 THE RESOLUTION OF O-METHYL O-PHENYL THIOPHOSPHORIC acid AND ABSOLUTE CONFIGURATIONS OF ITS OPTICAL ISOMERS ITS
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Development of <i>α</i>-Amino Acid Detection with Peroxyoxalate Chemiluminescence by Using Water-Acetonitrile-Ethyl Acetate Mixed Solution
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作者 Hyo Kan Ryo Mizutani Kazuhiko Tsukagoshi 《American Journal of Analytical Chemistry》 2020年第1期15-24,共10页
Peroxyoxalate chemiluminescence was, for the first time, examined by using ternary mixed solutions of water-hydrophilic/hydrophobic organic solvent. Eosin Y as a model fluorescence compound was dissolved with the tern... Peroxyoxalate chemiluminescence was, for the first time, examined by using ternary mixed solutions of water-hydrophilic/hydrophobic organic solvent. Eosin Y as a model fluorescence compound was dissolved with the ternary solutions of water (1.0 mM carbonate buffer, pH 9.0)-acetonitrile-ethyl acetate, water-rich of 15:3:2 volume ratio and organic solvent-rich of 3:8:4 volume ratio, to which bis(2,4,6-trichlorophenyl) oxalate and hydrogen peroxide chemiluminescence reagent were added. The chemiluminescence observed with the ternary solutions, especially the organic solvent-rich solution, showed a larger signal than that observed with the water only solution or water-acetonitrile mixed solution. Chemiluminescence in the presence of twenty types of α-amino acid was similarly examined by using the ternary organic solvent-rich solution. The chemiluminescence of three α-amino acids with fluorescence properties was enhanced with the ternary solution. The data reported here may contribute to development of a new, sensitive peroxyoxalate chemiluminescence detection system. 展开更多
关键词 PEROXYOXALATE chemiluminescence α-amino acids Water-Acetonitrile-Ethyl Acetate Bis(2 4 6-Trichlorophenyl) OXALATE
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Synthetic Approach for Novel Fluorine Substituted <i>α</i>-Aminophosphonic Acids Containing 1,2,4-Triazin-5-One Moiety as Antioxidant Agents
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作者 Mohammed S. T. Makki Reda M. Abdel-Rahman Abdulrahman S. Alharbi 《International Journal of Organic Chemistry》 2018年第1期1-15,共15页
Novel fluorine substituted α-amino phosphonic acids containing 1,2,4-triazin- 5-one (6a-f) have been obtained from fluoroacylation of 6-(2&prime;-amino-5&prime;-nitrophenyl)-3-thioxo-1,2,4-triazin-5(4H)-one (... Novel fluorine substituted α-amino phosphonic acids containing 1,2,4-triazin- 5-one (6a-f) have been obtained from fluoroacylation of 6-(2&prime;-amino-5&prime;-nitrophenyl)-3-thioxo-1,2,4-triazin-5(4H)-one (1) followed by ammonilysis to give the corresponding 3-amino-derivative 3. Condensation of compound 3 with nitro/halogenated aromatic aldehydes yielded the Schiff bases 4. The simple addition of diethyl phosphonate to compound 4 produced the α-amino phosphonates 5. Acidic hydrolysis of compound 5 produced the fluorine substituted α-amino acids derivatives 6. Structures of the new compounds have been established with the help of elemental analysis and spectral measurements. Also, the products evaluated as antioxidants, where the fluorinated α-amino phosphonic acids 6 are more active than the other synthesized systems. 展开更多
关键词 Synthetic FLUORINE α-amino acids 1 2 4-Triazin-5-One MOIETY ANTIOXIDANTS Activity
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Evaluation of the Anti-Inflammatory Activities of 5,8,11-<i>cis</i>-Eicosatrienoic Acid
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作者 Lun-Chung Hsu Zhi-Hong Wen +3 位作者 Han-Min Chen Han-Tzo Lin Chi-Ming Chiu Hui-Chung Wu 《Food and Nutrition Sciences》 2013年第9期113-119,共7页
The main eicosanoids inflammatory mediators, prostaglandins and leukotrienes, are both generated from arachidonic acid (AA;20:4 n-6). AA is a member of polyunsaturated fatty acids (PUFAs). Numerous studies have demons... The main eicosanoids inflammatory mediators, prostaglandins and leukotrienes, are both generated from arachidonic acid (AA;20:4 n-6). AA is a member of polyunsaturated fatty acids (PUFAs). Numerous studies have demonstrated that various contents of PUFAs can modulate the inflammatory responses. However, fewer studies have examined n-9PUFAs and their effects on the inflammatory responses. In the present study, the role of 5,8,11-cis-eicosatrienoic acid (ETrA;20:3 n-9, also called Mead acid) in the inflammatory responses has been investigated. The anti-inflammatory activities of ETrA were examined using an in vitro macrophage system and the inhibitory effect was confirmed by western blot analysis for iNOS and COX-2 expressions. The interactions between ETrA and COX-2 protein were simulated to produce a computer modeling protein-ligand complexes and the results suggest a possible mechanism for the effects of ETrA. In this study, we described a significant inhibition of the inflammatory activities initiated by ETrA. Since ETrA is a substance presented in the tissues of young animals, we therefore anticipate that ETrA can be utilized as a natural therapeutic supplement to inhibit inflammatory activities. 展开更多
关键词 5 8 11-cis-Eicosatrienoic acid ANTI-INFLAMMATORY Activities COX-2 INOS PUFAS
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