微生物来源的醛糖还原酶抑制剂F01-195A的研究

利用自建的高通量醛糖还原酶抑制剂的筛选方法,从数千株放线菌和真菌中筛选得到阳性菌株F01-195.对阳性菌株的发酵产物进行有机溶剂提取、硅胶柱色谱和ODS HPLC纯化,得到活性化合物F01-195A,其对醛糖还原酶有较强的特异性抑制活性,IC50为57.2μmol/L.通过对F01-195A的紫外、质谱、核磁等理化数据的分析,鉴定了其化学结构与化合物Flavomannin相同,Flavomannin已被报道作为了抗疟疾药物的先导化学物.     

真菌来源的乙酰胆碱酯酶抑制剂F01-2076A的研究

利用自建的乙酰胆碱酯酶抑制剂的高通量筛选模型,从大量真菌中筛选到1株阳性菌株F01-2076.该菌株的发酵液经有机溶剂提取、硅胶柱层析及HPLC ODS反相柱层析分离,得到1个活性化合物F01-2076A,该化合物对乙酰胆碱酯酶的IC50为23.4μmol/L.通过对该化合物的紫外、质谱、核磁等理化分析,得知该化合物与已知化合物Altenusin结构相同.     

弹性蛋白酶抑制剂筛选方法的建立及天然产物对其抑制活性观察

发现弹性蛋白酶抑制剂是治疗肺气肿等疾病药物的重要研发方向之一.本研究用弹性蛋白酶建立微量、高效的体外抑制剂筛选模型,利用西维来司钠作为阳性对照,验证了筛选模型的稳定性和灵敏度,并筛选了33种中药单体对弹性蛋白酶的抑制活性,其中部分化合物表现一定的抑制活性.     

刺五加根茎活性成分对蛋白酪氨酸磷酸酶1B的抑制作用

采用正相硅胶柱色谱、 C-18反相柱色谱和半制备型高效液相色谱（HPLC）等多种层析方法分离、 纯化刺五加根茎乙酸乙酯层中的降糖活性成分, 得到10个化合物, 通过核磁共振氢谱(¹H-NMR)、 核磁共振碳谱（¹³C-NMR）、 无畸变极化转换技术(DEPT)、 质谱（MS）等方法分析各化合物的光谱数据, 并与相关文献比较, 确定所得化合物的结构, 对其进行活性测试. 结果表明： 化合物1~5为贝壳杉烷型二萜类化合物, 化合物6~8为松脂烷型二萜类化合物, 化合物9,10为木脂素类化合物; 化合物1,5,7,8对蛋白酪氨酸磷酸酶1B(PTP1B)具有明显的特异性抑制活性, 化合物2,4,9对蛋白磷酸酶（PP1）具有较好的抑制活性,  化合物9,10对牛痘H1相关磷酸酶（VHR）的抑制活性作用较低.     

玉竹中高异黄酮类化合物生物活性研究

采用四唑盐(MTT)比色法、白细胞弹性蛋白酶抑制剂筛选模型及二氢乳清酸脱氢酶抑制剂筛选模型对从玉竹中分离出的4个高异黄酮类化合物进行生物活性评价,探讨化合物结构与其活性之间的构效关系.高异黄酮类化合物1～4对肿瘤细胞K562,A549和HCT-15具有细胞毒性,IC50为7～35μg/mL;化合物1～4对人白细胞弹性蛋白酶有抑制作用,IC50分别为13.1,70.4,13.8,55.2μg/mL;化合物2,4对二氢乳清酸脱氢酶有一定的抑制作用,IC50分别为10.0,11.1μg/mL.高异黄酮类化合物的生物活性与其取代基的类型及位置有关.     

产体外抗鼻咽癌物质红树林土壤细菌筛选及其活性成分分析

研究一株通过活性筛选获得的、具有抗鼻咽癌(Nasopharyngeal Carcinoma,NPC)活性物质生产潜力的细菌,对其所产活性物质进行分离纯化,以探讨其抗肿瘤研发价值。以鼻咽癌肿瘤细胞株TW03和5-8F作为测试对象,利用细胞计数试剂盒(Cell Counting Kit-8,CCK8)法从广西北海采集的红树林土壤中筛选出具有体外抗鼻咽癌活性物质生产潜力的细菌,通过基因分析、细菌形态以及生理生化特性对活性菌株进行分类鉴定,通过柱层析分离和活性测试追踪法从菌株的发酵液中获得具有体外抗鼻咽癌活性的化合物,并应用核磁共振波谱和低分辨质谱鉴定其结构。结果表明,经16S rRNA和看家基因(atpD和rpoB)的多位点序列分析鉴定菌株归属于链霉菌,命名为Streptomyces sp.MCCG 218。从该菌株的发酵液中分离得到一个活性化合物 1,经图谱分析和文献比对确认该化合物为巴弗洛霉素A1衍生物(17,18-dehydro-24-demethyl-bafilomycin A1),其对鼻咽癌细胞株TW03和5-8F表现出较强的细胞增殖抑制活性,半抑制浓度(Half Inhibitory Concentration,IC₅₀)值分别为2.7 μmol/L和9.2 μmol/L。红树林来源链霉菌MCCG 218能够生产具有抑制鼻咽癌细胞增殖活性的化合物巴弗洛霉素A1衍生物。     

苦瓜皂甙的分离以及PTP1B抑制活性

通过溶剂萃取、大孔树脂D-101去杂、正相硅胶柱粗分、ODS反相硅胶柱反复分离纯化、薄层色谱检测,从苦瓜中分离出5种化合物.借助于ESI-MS、IR、13C NMR、1H NMR、DEPT-NMR等波谱技术,对这5种化合物进行结构鉴定.结果表明,此5种化合物都属于皂甙类,其中化合物A是甾体皂甙,其余4种为四环三萜葫芦烷皂甙.这5个化合物分别为:A为α-菠甾醇-3-O-β-D-吡喃葡萄糖甙;B为19(R)-羰基-25-二甲氧基-5β-葫芦烷-6,23-二烯-3β,25-羟基-5-19环氧酯-3-O-β-D-吡喃葡萄糖甙;C为葫芦烷-5-烯-3β,22,23,24,25-五基-3-O-3-β-D-吡喃葡萄糖(1→6)-D-吡喃葡萄糖甙(苦瓜素A);D为葫芦烷-5,23-二烯-3p,7,25-羟基-9-醛基-7-O-β-D-吡喃葡萄糖甙(苦瓜素L);E为葫芦烷-5,23-二烯-3β,7-二羟基-9-醛基-25-甲氧基-7-O-β-D-吡喃葡萄糖甙(苦瓜素K).5种化合物进行PTP1B抑制活性筛选试验,结果表明,这5种皂甙单体中,化合物D和化合物E对PTP1B没有抑制活性,化合物A、B、C对PTP1B有不同程度的抑制活性,其中抑制活性大小为化合物A＞化合物C＞化合物B.     

白云鄂博稀土矿来源放线菌Actinorectispora metalli的次生代谢产物研究

对白云鄂博稀土矿来源放线菌Actinorectispora metalli KC 198~T的次生代谢产物进行研究,并测定其单体化合物的抗氧化活性.将放线菌A. metalli KC 198~Ti进行土豆液体培养基(PDB)发酵,然后采用乙酸乙酯萃取发酵产物;萃取物采用硅胶柱色谱、凝胶柱色谱、反相RP-18柱色谱等方法,分离纯化次生代谢产物;单体化学成分通过核磁共振波谱与质谱表征,并结合文献数据对比,确定单体化合物的化学结构,单体化合物采用DPPH的方法测试其抗氧化活性.从乙酸乙酯及正丁醇部分共分离得到7个单体化学成分,依次确定为(1) 1,4-dimethoxy-2-hydroxynaphthalene-2-O-β-D-glucopyranoside、(2) 4-hydroxy-tetralone、(3)环(L-色氨酸-L-脯氨酸)、(4)尿嘧啶、(5)胸腺嘧啶、(6) β-adenosine、(7) 3-(2,3-dihydroxypropyl) indole.对分离的结构进行抗氧化活性筛选,结果表明以上单体化合物在50μmol/L的浓度下,均未显示出较明显的抗氧化活性.化合物1为...     

贝莱斯芽孢杆菌BR-01菌株高产抗菌肽培养基的优化及其抗菌肽的鉴定

贝莱斯芽孢杆菌(Bacillus velezensis) BR-01菌株对水稻细菌性条斑病菌(Xanthomonas oryzae pv.oryzicola,Xoc)具有较好的拮抗作用。为了提高该菌株的抗菌肽发酵产量和生防价值,对其产抗菌肽培养基进行了优化,并初步鉴定了其抗菌肽的成分。以B.velezensis BR-01菌株无菌发酵滤液对Xoc的抑菌圈直径为评价指标,从7种常见培养基中筛选出最适培养基,通过单因素试验优化初始培养基各组分含量和发酵条件,再利用Plackett-Burman (PB)试验筛选出影响发酵滤液抑菌活性的显著因素,运用响应面分析法获得最优发酵条件。利用PCR分析B.velezensis BR-01基因组中抗菌肽合成相关基因;使用液相色谱-质谱联用(Liquid Chromatography-Mass Spectrometer, LC-MS)技术鉴定其产生的抗菌肽。结果表明,B.velezensis BR-01菌株最佳抗菌肽培养基配方与发酵条件为麦芽糖11.89 g/L、酵母提取物13.54 g/L、NaCl 5 g/L、KH₂PO     

真菌Alternaria sp.XZSBG-1的四氢蒽醌类次级代谢产物

采用硅胶、C-18反相硅胶、Sephadex LH-20等柱色谱及高效液相色谱技术对真菌Alternaria sp.XZSBG-1的次级代谢产物进行系统研究;采用波谱分析及与文献比对等方法鉴定化合物结构;采用MTT法和比色法进行抗肿瘤和酶抑制活性筛选。结果从真菌Alternaria sp.XZSBG-1的发酵物中分离得到8个四氢蒽醌类化合物,分别鉴定为Alterporriol F'(1)、Alterporriol G'(2)、Alterporriol F(3)、Alterporriol G(4)、Altersolanol A(5)、Altersolanol F(6)、Tetrahydroaltersolanol B(7)和Tetrahydroaltersolanol D(8);活性测试结果表明仅化合物6对结肠癌细胞株(HCT-116)和子宫癌细胞株(Hela)具有明显抑制活性,IC50值分别为3.026和8.094μmol/L。     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3～4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰～ -7.8‰, PDB) and matrix dolomites (-6.6‰～ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084～0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078～0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.     

橡胶颗粒沥青混合料低温抗裂性试验研究

以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

Quantitative trait loci （QTLs） for quality traits related to protein and starch in wheat

Quality traits in wheat （Triticum aestirum L.） were studied by quantitative trait locus （QTL） analysis in a recombinant inbred line （RIL） population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross （ChSh）. Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.