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Preparation and bioactivity evaluation of low salt peptide from sunf lower seed meal 预览
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作者 Tingting Guo Chuyun Wan Fenghong Huang 《Oil Crop Science-中国油料作物学报英文版》 2019年第2期118-126,共9页
Sunflower seed meal peptide as one sort of bioactive peptide has intensively application prospects. However, preparation of low salt peptide from sunflower seed meal with high efficiency remains a challenge. In this s... Sunflower seed meal peptide as one sort of bioactive peptide has intensively application prospects. However, preparation of low salt peptide from sunflower seed meal with high efficiency remains a challenge. In this study, single and compound proteases were optimized to hydrolyze protein. Results showed that hydrolysis at pH 7.0 by proteases resulted in ash content in the range of 5.66%-7.37% and small peptides. Among all hydrolysis processes, sequential hydrolysis of Alcalase with Flavourzyme and Alcalase with Protamex showed higher nitrogen recovery ratio (67.66% and 66.49%, respectively). Furthermore, biological activities of peptides were investigated by testing their ABTS (2,2-azinobis (3-ethylben-zothiazoline-6-sulfonic acid) diammonium salt) radical scavenging activity, DPPH (2,2-diphenyl-1-picrylhydrazil) radical scavenging activity and angiotensin converting enzyme (ACE) inhibitory activity. Peptide hydrolyzed by Alcalase with Papain presented the highest antioxidant activity, followed by Alcalase with Protamex, with ABTS scavenging rate as 63.01% and 31.75%, and DPPH scavenging rate as 56.04% and 28.06%, respectively. Synchronously, peptide hydrolyzed by Alcalase with Protamex and Alcalase with Alcalase had the highest ACE inhibitory activity (56.74%, 56.76%). In conclusion, hydrolysis by proteases Alcalase with Protamex at pH 7.0 was the most effective method for the preparation of low salt peptide from sunflower seed meal, which could be an alternative for anti-oxidants and anti-vasoconstrictor. 展开更多
关键词 low salt PEPTIDE SUNFLOWER seed MEAL compound ENZYME antioxidant ACTIVITY ANTIHYPERTENSIVE ACTIVITY
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Rapid discovery and identification of the anti-inflammatory constituents in Zhi-Shi-Zhi-Zi-Chi-Tang
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作者 WANG Hai-Qiang ZHU Yun-Xiang +2 位作者 LIU Yi-Ning WANG Ruo-Liu WANG Shu-Fang 《中国天然药物:英文版》 SCIE CAS CSCD 2019年第4期308-320,共13页
The anti-inflammatory active ingredients of Zhi-Shi-Zhi-Zi-Chi-Tang(ZSZZCT), a traditional Chinese medicine formula, were predicted and identified using an approach based on activity index, LC-MS, semi-preparative LC ... The anti-inflammatory active ingredients of Zhi-Shi-Zhi-Zi-Chi-Tang(ZSZZCT), a traditional Chinese medicine formula, were predicted and identified using an approach based on activity index, LC-MS, semi-preparative LC and NMR. Firstly, the whole extract of ZSZZCT was analyzed using liquid chromatography-quadrupole time of flight-mass spectrometry(LC-QTOF-MS) and liquid chromatography-ion trap mass spectrometry(LC-IT-MS), 79 constituents were detected and 39 constituents were identified unambiguously or tentatively. Subsequently, the whole extract of the formula was separated into multiple components and the activity index method was used to calculate index values of the 79 constituents by integrating the chemical and pharmacological information of multiple components. Four polymethoxyl flavones were predicted as the major active constituents according to the activity index values. Furthermore, three polymethoxyl flavones were prepared using the strategy with semipreparative LC guided by LC-MS, and their anti-inflammatory activities were validated. The results show that three polymethoxyl flavones with higher positive index values, i.e., 3, 5, 6, 7, 8, 3’, 4’-heptamethoxyflavone, 3-hydroxynobiletein and tangeretin had significant anti-inflammatory effects. In conclusion, the predicted results indicated that the activity index method is feasible for the accurate prediction of active constituents in TCM formulae. 展开更多
关键词 Zhi-Shi-Zhi-Zi-Chi-Tang LC-MS Semi-preparative LC NMR ACTIVITY index ANTI-INFLAMMATORY ACTIVITY
学术活动与习惯 预览
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作者 冯东飞 白亚平 《延安大学学报:社会科学版》 2019年第2期32-36,共5页
人实质上就是一种习惯性存在物,其行为习惯像血液似的融入于生命体之中,人的任何行为习惯都是在自己长期实践活动过程中积淀形成的。作为人类活动重要形式之一的学术活动,其过程也是与行为习惯密不可分的,学术活动行为习惯有良好习惯与... 人实质上就是一种习惯性存在物,其行为习惯像血液似的融入于生命体之中,人的任何行为习惯都是在自己长期实践活动过程中积淀形成的。作为人类活动重要形式之一的学术活动,其过程也是与行为习惯密不可分的,学术活动行为习惯有良好习惯与不良习惯之分。抑制不良习惯,弘扬良好习惯,对于从事学术活动的研究者极为重要。 展开更多
关键词 活动 学术活动 习惯
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Antioxidant and antitumor potential of wild and IMTA-cultivated Osmundea pinnatifida 预览
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作者 SILVA J. Paulo ALVES Celso +4 位作者 PINTEUS Susete SILVA Joana VALADO Ana PEDROSA Rui PEREIRA Leonel 《海洋湖沼学报(英文)》 SCIE CAS CSCD 2019年第3期825-835,共11页
Osmundea pinnatifida is a red edible seaweed known as pepper dulse.O.pinnatifida was cultivated in the farm of ALGAplus(ílhavo,Portugal).This farm is integrated with a seabream and seabass commercial aquaculture ... Osmundea pinnatifida is a red edible seaweed known as pepper dulse.O.pinnatifida was cultivated in the farm of ALGAplus(ílhavo,Portugal).This farm is integrated with a seabream and seabass commercial aquaculture and uses the nutrient-enriched water resultant from the fish production as its cultivation medium in the integrated multi-trophic aquaculture(IMTA)manner.Wild and IMTA-cultivated samples of O.pinnatifi da were screened for antioxidant and antitumor activities.The antioxidant capacity of solvent extracts from wild and IMTA cultivated samples was assessed in two methods(2,2-diphenyl-1-picrylhydrazyl(DPPH)and oxygen radical absorbance capacity(ORAC)),and their total phenolic contents(TPC)were estimated.Antitumor activity was evaluated in three different tumor cell lines(HepG-2,MCF-7,and SH-SY5Y)through 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT)assay.Among the solvents used for extraction,dichloromethane was the most eff ective to extract phenolic compounds and presented higher ORAC.A significant correlation was found between TPC and ORAC,which was also sustained by the principal components analysis(PCA).Dichloromethane extracts induced a cytostatic eff ect on MCF-7 cells and showed weak cytotoxicity to SH-SY5Y cells and weak impact on cell proliferation.Overall,there were no statistically signifi cant differences in the biological activities shown by the wild and IMTA-cultivated samples.Hence,O.pinnatifida can be obtained in an economical and environmentally sustainable way through IMTA,maintaining bioactive properties in a high potential for further nutraceutical purposes. 展开更多
关键词 EDIBLE SEAWEED bioactive compounds POLYPHENOLS cytotoxic ACTIVITY ANTIPROLIFERATIVE ACTIVITY
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Android程序调用机制研究 预览
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作者 张天 耿庆田 高琦坤 《长春师范大学学报》 2019年第4期48-50,共3页
随着“互联网+”和大数据的应用推广,移动终端相当普及,基于Android平台开发的应用越来越多,有些应用在开发测试阶段可能需要反复大量调用硬件设备或者第三方程序,在调用时可能会耗费很多时间。为提高开发效率,本文基于Android应用程序... 随着“互联网+”和大数据的应用推广,移动终端相当普及,基于Android平台开发的应用越来越多,有些应用在开发测试阶段可能需要反复大量调用硬件设备或者第三方程序,在调用时可能会耗费很多时间。为提高开发效率,本文基于Android应用程序运行机制,提出Intent对象属性替换方法,以实现第三方程序调用的替换,来节省应用程序开发的调试时间。 展开更多
关键词 ANDROID ACTIVITY INTENT 程序调用
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Design, Synthesis, Biological Activity and Molecular Docking Study of Coumarin Derivatives Bearing 2-MethyIbiphenyl Moiety
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作者 MA Junjie HUANG Kun +3 位作者 NI Xin CHEN Roufen XU Boxuan WANG Cuifang 《高等学校化学研究:英文版》 SCIE CAS CSCD 2019年第3期410-417,共8页
A hybrid pharmacophore approach was used to design and synthesize a series of coumarin derivatives bearing 2-methylbiphenyl moiety, which were evaluated for their in vitro anticancer activities against four cancer cel... A hybrid pharmacophore approach was used to design and synthesize a series of coumarin derivatives bearing 2-methylbiphenyl moiety, which were evaluated for their in vitro anticancer activities against four cancer cell lines(MCF-75 A549, H460 and HT29) and PD-1/PD-L1 inhibitory activities. Moreover, several compounds with excellent anticancer activities were selected to evaluate the cytotoxicities against one normal cell line(HEK-293). The most promising compound llo showed the best anticancer activities against the four tested cancer cell lines with the IC50 values of 6.45, 8.65, 6,57 and 8.13 gmol/L, respectively, and displayed weak cytotoxicity on the normal cell(HEK-293). Furthermore, screening of PD-1 /PD-L1 inhibitory activity revealed that compound llo could effectively inhibit the binding of PD-1/PD-L1, and the binding interactions of compound llo with PD-L1 protein were explored by molecular docking. All above evidences showed that compound llo might be worthy of further study as a valuable leading compound for the treatment of cancer. 展开更多
关键词 COUMARIN 2-Methylbiphenyl Anticancer ACTIVITY PD-1/PD-L1 inhibitory ACTIVITY MOLECULAR docking
Antioxidant and Anti-inflammatory Capacity of Ferulic Acid Released from Wheat Bran by Solid-state Fermentation of Aspergillus niger 预览
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作者 YIN Zhi Na WU Wen Jia +10 位作者 SUN Chong Zhen LIU Hui Fan CHEN Wen Bo ZHAN Qi Ping LEI Zhuo Gui XIN Xuan MA Juan Juan YAO Kun MIN Tian ZHANG Meng Meng WU Hui 《生物医学与环境科学:英文版》 SCIE CAS CSCD 2019年第1期11-21,共11页
Objective A strain of Aspergillus niger(A. niger), capable of releasing bound phenolic acids from wheat bran, was isolated. This strain was identified by gene sequence identification. The antioxidant and anti-inflamma... Objective A strain of Aspergillus niger(A. niger), capable of releasing bound phenolic acids from wheat bran, was isolated. This strain was identified by gene sequence identification. The antioxidant and anti-inflammatory capacity of ferulic acid released from wheat bran by this A. niger strain(FA-WB) were evaluated. Methods Molecular identification techniques based on PCR analysis of specific genomic sequences were conducted;antioxidant ability was examined using oxygen radical absorbance capacity(ORAC), cellular antioxidant activity(CAA) assays, and erythrocyte hemolysis assays. RAW264.7 cells were used as a model to detect anti-inflammatory activity. Results The filamentous fungal isolate was identified to be A. niger. ORAC and CAA assay showed that FA-WB had better antioxidant activity than that of the ferulic acid standard. The erythrocyte hemolysis assay results suggested that FA-WB could attenuate AAPH-induced oxidative stress through inhibition of reactive oxy gen species(ROS) generation. FA-WB could significantly restore the AAPH-induced increase in intracellular antioxidant enzyme activities to normal levels as well as inhibit the intracellular malondialdehyde formation. TNF-?, IL-6, and NO levels indicated that FA-WB can inhibit the inflammation induced by lipopolysaccharide(LPS). Conclusion Ferulic acid released from wheat bran by a new strain of A. niger had good anti-inflammatory activity and better antioxidant ability than standard ferulic acid. 展开更多
关键词 FUNGAL identification Fermentation Ferulic acid ANTIOXIDANT ACTIVITY Oxidative HEMOLYSIS ANTI-INFLAMMATORY activity.
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Identification and characterization of two novel cathelicidins from the frog Odorrana livida
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作者 Ruo-Han Qi Yan Chen +5 位作者 Zhi-Lai Guo Fen Zhang Zheng Fang Kai Huang Hai-Ning Yu Yi-Peng Wang 《动物学研究》 CAS CSCD 2019年第2期94-101,共8页
Antimicrobial peptides(AMPs) are a group of gene-encoded small peptides that play pivotal roles in the host immune system of multicellular organisms.Cathelicidins are an important family of AMPs that exclusively exist... Antimicrobial peptides(AMPs) are a group of gene-encoded small peptides that play pivotal roles in the host immune system of multicellular organisms.Cathelicidins are an important family of AMPs that exclusively exist in vertebrates. Many cathelicidins have been identified from mammals, birds, reptiles and fish. To date, however, cathelicidins from amphibians are poorly understood. In the present study, two novel cathelicidins(OL-CATH1 and 2) were identified and studied from the odorous frog Odorrana livida.Firstly, the cDNAs encoding the OL-CATHs(780 and735 bp in length, respectively) were successfully cloned from a lung cDNA library constructed for the frog. Multi-sequence alignment was carried out to analyze differences between the precursors of the OL-CATHs and other representative cathelicidins.Mature peptide sequences of OL-CATH1 and 2 were predicted(33 amino acid residues) and their secondary structures were determined(OL-CATH1 showed a random-coil conformation and OL-CATH2 demonstrated α-helical conformation). Furthermore,OL-CATH1 and 2 were chemically synthesized and their in vitro functions were determined. Antimicrobial and bacterial killing kinetic analyses indicated that OL-CATH2 demonstrated relatively moderate and rapid antimicrobial potency and exhibited strong anti-inflammatory activity. At very low concentrations(10 μg/mL), OL-CATH2 significantly inhibited the lipopolysaccharide(LPS)-induced transcription and production of pro-inflammatory cytokines TNF-α, IL-1βand IL-6 in mouse peritoneal macrophages. In contrast, OL-CATH1 did not exhibit any detectableantimicrobial or anti-inflammatory activities. Overall,identification of these OL-CATHs from O. livida enriches our understanding of the functions of cathelicidins in the amphibian immune system. The potent antimicrobial and anti-inflammatory activities of OL-CATH2 highlight its potential as a novel candidate in anti-infective drug development. 展开更多
关键词 ANTIMICROBIAL peptides (AMPs) CATHELICIDINS ODORRANA livida OL-CATHs ANTIMICROBIAL ACTIVITY ANTI-INFLAMMATORY ACTIVITY
南京市工业项目工程机械大气污染物排放清单研究 预览
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作者 林家宝 陈洁 张静 《四川环境》 2019年第3期83-87,共5页
通过对金陵石化及扬子石化两个特大施工工地活动水平的研究,根据收集的南京市工业项目工程机械数据资料,采用合适的估算方法和排放因子,据此建立了2017年南京市工业项目工程机械大气污染物排放清单。结果表明,2017年南京市工业项目工程... 通过对金陵石化及扬子石化两个特大施工工地活动水平的研究,根据收集的南京市工业项目工程机械数据资料,采用合适的估算方法和排放因子,据此建立了2017年南京市工业项目工程机械大气污染物排放清单。结果表明,2017年南京市工业项目工程机械共排放NOx13072.13kg,占工程机械污染物排放总量的55.79%,为最大污染贡献源;CO排放总量为6194.17kg、VOC排放总量为1511.82kg、PM10排放总量为932.20kg、SO2排放总量为1068.42kg、PM2.5排放总量为651.74kg。在所有工程机械的使用过程中,挖掘机为最大污染贡献源,占污染物排放总量的30.22%;其次为200t以下吊车(起重机),占比为20.41%;压路机、搅拌机分别为第三、第四污染贡献源,占比分别为17.81%、15.18%。 展开更多
关键词 工程机械 排放清单 大气污染物 活动水平 南京市
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毛尖茶叶中的黄酮类化合物对脂氧合酶的抑制性 预览
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作者 吴桂玲 代虹镜 +1 位作者 邓維先 罗骏 《云南化工》 CAS 2019年第4期65-67,共3页
采用紫外可见光分光光度法,以亚油酸钠为底物,研究了都匀毛尖茶叶中的黄酮类化合物对大豆脂氧合酶活性的抑制作用。结果表明,毛尖茶叶中的黄酮类化合物的提取率为5.227%,毛尖茶叶中的黄酮类化合物对大豆脂氧合酶有一定的抑制效果,并且... 采用紫外可见光分光光度法,以亚油酸钠为底物,研究了都匀毛尖茶叶中的黄酮类化合物对大豆脂氧合酶活性的抑制作用。结果表明,毛尖茶叶中的黄酮类化合物的提取率为5.227%,毛尖茶叶中的黄酮类化合物对大豆脂氧合酶有一定的抑制效果,并且随着黄酮类化合物的浓度的增加抑制效果增强。 展开更多
关键词 黄酮类化合物 脂氧合酶 活性 抑制作用
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Sedimentary geochemical proxies for methane seepage at Site C14 in the Qiongdongnan Basin in the northern South China Sea 预览
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作者 Tiantian Sun Daidai Wu +3 位作者 Fei Yang Lihua Liu Xuegang Chen Ying Ye 《海洋学报:英文版》 SCIE CAS CSCD 2019年第7期84-95,共12页
Recent studies have shown that specific geochemical characteristics of sediments can be used to reconstruct past methane seepage events.In this work,the correlation between the Sr/Ca and Mg/Ca ratios of sediment sampl... Recent studies have shown that specific geochemical characteristics of sediments can be used to reconstruct past methane seepage events.In this work,the correlation between the Sr/Ca and Mg/Ca ratios of sediment samples is analyzed and the sulfate concentration profile in Site C14 from cold-seep sediments in the Qiongdongnan Basin in northern South China Sea is obtained.The results confirmed that,sulfate at 0–247 cm below sea floor(Unit I)is mainly consumed by organic matter sulfate reduction(OSR),while sulfate at 247–655 cm(UnitⅡ)is consumed by both the OSR and the anaerobic oxidation of methane(AOM).In addition,the bottom sediment layer is affected by weak methane seepage.The Mo and U enrichment factors also exhibit similar trends in their respective depth profiles.The responses of trace elements,including Co/Al,Ni/Al,Cr/Al and Zn/Al ratios to methane seepage allowed the study of depositional conditions and methane seepage events.Based on the results,it is speculated that the depositional conditions of UnitⅡchanged with depth from moderate conditions of sulfidic and oxic conditions to locally anoxic conditions,and finally to suboxic conditions due to methane fluid leakage.The stable isotope values of chromium-reducible sulfide produced by AOM and those of sulfide formed by OSR in the early diagenetic environment suffered serious depletion of 34S.This was probably due to weak methane leakage,which caused the slower upward diffusion and the effect of early diagenesis on the samples.It is necessary to consider the effects of depositional environments and diagenesis on these geochemical parameters. 展开更多
关键词 Qiongdongnan Basin trace elements stable ISOTOPE values ANAEROBIC oxidation of METHANE METHANE activity
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The origins of food 预览
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作者 Andy Keedwell 《新世纪智能》 2019年第8期37-39,共3页
Where does our food come from?Once upon a time carrots were purple, there were no pineapples in Asia or lemons in America, and many people thought potatoes were poisonous. Many types of fruit and vegetable grew only i... Where does our food come from?Once upon a time carrots were purple, there were no pineapples in Asia or lemons in America, and many people thought potatoes were poisonous. Many types of fruit and vegetable grew only in one place. So how did they spread all over the world? 展开更多
关键词 ACTIVITY The origins of FOOD
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Activities of Biapenem against Mycobacterium tuberculosis in Macrophages and Mice 预览
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作者 GUO Zhen Yong ZHAO Wei Jie +4 位作者 ZHENG Mei Qin LIU Shuo YAN Chen Xia LI Peng XU Shao Fa 《生物医学与环境科学:英文版》 SCIE CAS CSCD 2019年第4期235-241,共7页
Objective To assess the activities of biapenem against multidrug-resistant and extensively drug-resistant Mycobacterium tuberculosis. Methods Biapenem/clavulanate(BP/CL) was evaluated for in vitro activity against Myc... Objective To assess the activities of biapenem against multidrug-resistant and extensively drug-resistant Mycobacterium tuberculosis. Methods Biapenem/clavulanate(BP/CL) was evaluated for in vitro activity against Mycobacterium tuberculosis(Mtb) multidrug-resistant(MDR) isolates, extensively drug-resistant(XDR) isolates, and the H37 RV strain. BP/CL activity against the H37 Rv strain was assessed in liquid cultures, in macrophages, and in mice. Results BP/CL exhibited activity against MDR and XDR Mtb isolates in liquid cultures. BP/CL treatment significantly reduced the number of colony forming units(CFU) of Mtb within macrophages compared with control untreated infected macrophages. Notably, BP/CL synergized in pairwise combinations with protionamide, aminosalicylate, and capreomycin to achieve a fractional inhibitory concentration for each pairing of 0.375 in vitro. In a mouse tuberculosis infection model, the efficacy of a cocktail of levofloxacin + pyrazinamide + protionamide + aminosalicylate against Mtb increased when the cocktail was combined with BP/CL, achieving efficacy similar to that of the positive control treatment(isoniazid + rifampin + pyrazinamide) after 2 months of treatment. Conclusion BP/CL may provide a new option to clinically treat MDR tuberculosis. 展开更多
关键词 BIAPENEM CLAVULANATE MULTIDRUG resistant EXTENSIVE DRUG-RESISTANT MYCOBACTERIUM tuberculosis Activity Macrophage Synergy
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The synthesis of 6-(tert-butyl)-8-fluoro-2,3-dimethylquinoline carbonate derivatives and their antifungal activity against Pyricularia oryzae
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作者 Long Cheng Ruirui Zhang +2 位作者 Hongke Wu Xinghai Liu Tianming Xu 《化学科学与工程前沿:英文版》 EI CAS CSCD 2019年第2期369-376,共8页
A series of novel 6-(/er/-butyl)-8-fluoro-2,3- dimethylquinoline carbonate derivatives were designed and synthesized. Bioassay results showed that some of them exhibited good activity against Pyricularia oryzae (P. or... A series of novel 6-(/er/-butyl)-8-fluoro-2,3- dimethylquinoline carbonate derivatives were designed and synthesized. Bioassay results showed that some of them exhibited good activity against Pyricularia oryzae (P. oryzae). It was found that the compound 5q (benzyl (6-(tert-butyl)-8-fluoro-2,3-dimethylquinolin-4-yl) carbonate) possessed good activity against P. oryzae whatever protective activity (10 mg·L^-1) or curative activity (25 mg·L^-1), which was better than that of control tebufloquin. In addition, the frontier molecular orbit results revealed that the compound held higher activity against P. oryzae when the total energy was low and the ClogP was high, which may provide useful information for further design novel fungicides. 展开更多
关键词 QUINOLINE synthesis ANTIFUNGAL activity rice BLAST SAR
Solid-Phase Enzymatic Peptide Synthesis to Produce an Antioxidant Dipeptide 预览
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作者 Yuyao Shan Mengfan Wang +2 位作者 Wei Qi Rongxin Su Zhimin He 《天津大学学报:英文版》 EI CAS 2019年第3期276-282,共7页
Peptide bond synthesis is favorable to the production of bioactive small peptides.However,the abuse of toxic reagents remains an issue for chemical synthesis method,whereas the low product yield and purity limit the w... Peptide bond synthesis is favorable to the production of bioactive small peptides.However,the abuse of toxic reagents remains an issue for chemical synthesis method,whereas the low product yield and purity limit the widespread use of enzymatic method.In this study,a new solid-phase enzymatic peptide synthesis(SPEPS) strategy was developed to produce an antioxidant tyrosine-alanine dipeptide(Tyr-Ala) by using recombinant carboxypeptidase Y(CPY) as the catalyst.The general SPEPS procedure involves three steps.First,the N-protected acyl donor was covalently attached to solid resin.Second,the peptide bond was condensed between the acyl donor and the nucleophile under the catalysis of CPY.Finally,one-step cleavage was performed to remove the protecting group and cleave the peptides from solid resin.Upon the optimization of reaction conditions,77.92%(±2.723%) yield of Tyr-Ala with high product purity of 90.971%(±2.695%) was obtained.In addition,the antioxidant activity of Tyr-Ala was determined by ABTS method,indicating that the synthesized Tyr-Ala obtained by SPEPS showed a superior antioxidant capability compared with commercial glutathione. 展开更多
关键词 SOLID-PHASE ENZYMATIC PEPTIDE synthesis CARBOXYPEPTIDASE Y Tyrosine-alanine Antioxidant activity
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Effect of Particle Size on Gasification Reactivity of Different Rank Coal Chars 预览
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作者 Li Wenxiu Rong Ling Kun Jia Feng Jun 《环境科学前沿:中英文版》 2019年第1期8-12,共5页
In the current research process of coal rank char gasification reaction in China, it is found that particle size has different influence on the gasification reactivity of coal char of different ranks. Therefore, monod... In the current research process of coal rank char gasification reaction in China, it is found that particle size has different influence on the gasification reactivity of coal char of different ranks. Therefore, monodisperse pulverized coal was prepared from eight kinds of coal chars of different ranks in entrained-flow gasifier. The particle size and gasification temperature of coal char were analyzed for these samples. The degree of influence of carbon dioxide gasification reaction. Through research and analysis, the performance differences of these samples under different carbon conversion rates were compared, and the sample reaction under high carbon conversion rates was discussed. The experimental results show that the orderliness of the microcrystalline structure of coal char is directly proportional to the rank of coal, while the gasification activity of coal char is inversely proportional to the rank of coal. Therefore, for different coal ranks, the influence of coal char particle size on coal char gasification reaction is different. According to the experiments, smaller coal char size and higher gasification temperature can promote the reactivity of higher-order coal gasification. In order to clarify the correlation between particle size and gasification reactivity of coal chars with different ranks, this paper discussed this issue. 展开更多
关键词 Particle Size DIFFERENT RANKS of COAL GASIFICATION Activity of COAL CHAR
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血浆D-二聚体水平在抗中性粒细胞胞浆抗体相关性血管炎中的临床意义
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作者 刘星 谢丽娇 +8 位作者 张齐武 张均 贺江花 唐莎 王卫黎 张莹 黄云剑 赵景宏 张静波 《免疫学杂志》 CAS CSCD 北大核心 2019年第3期241-247,共7页
目的探讨D-二聚体(D-dimer)在抗中性粒细胞胞浆抗体相关性血管炎(anti-neutrophil cytoplasmic antibody-associated vasculitis,AAV)患者中的临床意义。方法回顾性分析2014年5月至2017年11月我院肾内科穿刺活检确诊的50例ANCA相关性血... 目的探讨D-二聚体(D-dimer)在抗中性粒细胞胞浆抗体相关性血管炎(anti-neutrophil cytoplasmic antibody-associated vasculitis,AAV)患者中的临床意义。方法回顾性分析2014年5月至2017年11月我院肾内科穿刺活检确诊的50例ANCA相关性血管炎患者的临床资料。采用免疫比浊法检测血浆D-二聚体水平,以其中位数(3.17 mg/L FEU)为截点值将AAV患者分成高低水平2组,低水平组D-dimer<3.17 mg/L FEU,高水平组D-dimer≥3.17 mg/L FEU,比较2组患者临床特征、实验室检查、肾脏病理及预后差异。结果①高水平组患者C反应蛋白(C-reaction protein,CRP)、白细胞介素6(Interleukin-6,IL-6)水平及伯明翰血管炎活动性评分(Birmingham vasculitis activity score,BVAS)高于低水平组(P值分别为0.001、0.015、0.055),24小时尿蛋白定量、血清白蛋白(albumin,Alb)低于低水平组(P值分别为0.031、0.006)。②AAV患者血浆D-二聚体水平与BVAS(r=0.322,P=0.022)、CRP(r=0.573,P<0.001)、IL-6(r=0.341,P=0.015)、肿瘤坏死因子α(tumor necrosis factor alpha,TNF-α)(r=0.343,P=0.015)呈正相关。③肾脏病理特征:相较于高水平组患者,低水平组中球性硬化百分比较高(P=0.002),新月体形成的患者较少(P=0.247)。高水平组中细胞性新月体形成的患者数较低水平组多(P=0.017),且百分比高于低水平组(P=0.027)。④血浆D-二聚体(AUC=0.707)评估活动性AAV的预后无统计学差异(P>0.05)。结论血浆D-二聚体水平与AAV患者疾病活动性密切相关,有望成为评估AAV活动性的生物学标志物。 展开更多
关键词 D-二聚体 抗中性粒细胞胞浆抗体 血管炎 活动性
炭黑活性的测试方法研究 预览
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作者 王丹 邓旺 吴晓宇 《橡胶科技》 2019年第4期226-230,共5页
研究几种牌号炭黑活性的测试方法。结果表明:对于炭黑N326,N134,N115,N220和N234,相对活性、红外光谱、结合胶含量和物理性能4种方法测试的炭黑活性具有高度一致性。相对活性大的炭黑,红外光谱活性基团吸收峰明显,其胶料结合胶含量大,... 研究几种牌号炭黑活性的测试方法。结果表明:对于炭黑N326,N134,N115,N220和N234,相对活性、红外光谱、结合胶含量和物理性能4种方法测试的炭黑活性具有高度一致性。相对活性大的炭黑,红外光谱活性基团吸收峰明显,其胶料结合胶含量大,物理性能和耐磨性能好。建议有条件的企业测试炭黑的相对活性和红外光谱,条件有限的企业测试结合胶含量。 展开更多
关键词 炭黑 反相气相色谱 红外光谱 活性 结合胶含量 耐磨性能
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调动学生积极性提高教学实战技能 预览
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作者 胡要花 韩运侠 韩礼刚 《教育教学论坛》 2019年第30期212-213,共2页
结合笔者指导物理学专业师范生教学技能实训实践的经历,分析师范生教学技能实训课中学生积极性减弱的原因,并对调动学生积极性提出对策,有效地激发学生的积极性,为开展师范生课堂教学技能实训工作提供参考。
关键词 师范生 课堂教学技能 中学物理 积极性
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艾叶精油对玉米螟赤眼蜂的影响及两者对米蛾的联合作用 预览
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作者 杨小蓉 王智楠 +3 位作者 江浩林 田永清 张佩文 张志祥 《环境昆虫学报》 CSCD 北大核心 2019年第3期619-625,共7页
玉米螟赤眼蜂是生物防治中一种重要的天敌昆虫,为探明艾叶精油对玉米螟赤眼蜂的影响及两者对米蛾的联合防治效果,本文研究了艾叶精油熏蒸、触杀、驱避活性对玉米螟赤眼蜂的影响及艾叶精油和玉米螟赤眼蜂对米蛾的联合作用。结果表明,艾... 玉米螟赤眼蜂是生物防治中一种重要的天敌昆虫,为探明艾叶精油对玉米螟赤眼蜂的影响及两者对米蛾的联合防治效果,本文研究了艾叶精油熏蒸、触杀、驱避活性对玉米螟赤眼蜂的影响及艾叶精油和玉米螟赤眼蜂对米蛾的联合作用。结果表明,艾叶精油熏蒸和触杀处理对玉米螟赤眼蜂卵具有明显影响,寄生在米蛾卵上的玉米螟赤眼蜂卵经0.1、0.2、0.3、0.4、0.5、0.6μg/cm3艾叶精油熏蒸处理72h后玉米螟赤眼蜂的羽化率分别为56.67%、49.33%、44.00%、33.33%、26.00%和14.67%;寄生在米蛾卵上的玉米螟赤眼蜂卵经100、200、300、400、500、600mg/L艾叶精油触杀处理72h后玉米螟赤眼蜂的羽化率分别为54.00%、45.33%、38.00%、28.67%、18.00%和6.00%,均与对照组表现出显著性差异。艾叶精油驱避活性对玉米螟赤眼蜂成蜂也有明显的影响,300mg/L艾叶精油对玉米螟赤眼蜂的驱避率79.05%,随着时间间隔和距离间隔的增加,这种影响作用降低;联合应用艾叶精油与玉米螟赤眼蜂时先释放玉米螟赤眼蜂,24h后再滴加艾叶精油的防治效果最佳,米蛾的死亡率可高达96%。 展开更多
关键词 艾叶油 赤眼蜂 米蛾 活性
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