314 resultados para 21-210


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本研究通过选择性富集培养,从辽河油田稠油污染土壤中获得了能以2000mg·L~(-1)菲为唯一碳源和能源快速生长的优势降解菌株ZL5,经165 roNA序列分析认其属变形细菌a亚类中的鞘氨醇单胞菌属。ZL5菌株具有较强的降解菲、花能力,但是不能以蔡为唯一碳源和能源生一氏。外加碳源葡萄糖能有效促进PAHs降解,降解率提高达18.21-23.5%,但糖过量会表现出抑制效应。菌株ZL5含有一个大小约为60 kb的内生大质粒。丝裂霉素C消除试验表明,随着质粒丢失,菌株利用菲和花的能力也丧失。应用电转化和氯化铆转化将质粒导入大肠杆菌中,转化子获得了相应的降解菲、花能力,表明菌株ZLS的内生大质粒是与代谢PAHs功能有关的降解质粒。菌株ZL5具有PAHs诱导的邻苯二酚2,3-双加氧酶酶活(C230),指明其能以菲为唯一碳源和能源生长但不能降解蔡的原因可能为一未见报道的菲代谢新途径-水杨酸和邻苯二酚途径。采用特异性引物,扩增菌株ZLS的C230编码基因全序列,再与表达载体pET-30a(+)连接,实现了在E.coli JM109(OE3)中的高效表达。SDS-PAGE结果表明:C230蛋白不仅在细胞内存在,也能被大量地分泌到胞外,属国内首次报道。经Southern杂交,将菌株ZLS的C230基因定位在内生大质粒的不同酶切片段上。

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生态系统评价是为了向决策者提供生态系统管理信,息而对生态系统结构、功能进行分析,并根据其变化趋势及驱动力提出相应措施的综合研究过程。生态功能分区是依据生态系统胁迫过程与效应、生态环境质量、敏感性和生态系统服务功能重要性等特征空间分异规律而进行的地理空间分区,目的是辨析区域生态环境问题与生态环境脆弱区和良好区,明确优先保护的生态系统和地区,为生态保护与建设、产业结构调整与优化及区域生态系统分区管理提供科学依据。本研究以辽宁省域生态系统为对象,在生态环境调查的基础上,分析了生态环境状况及变化趋势,进行了生态环境质量、敏感性和生态系统服务功能重要性评价,辨析了存在的生态环境问题及驱动力,明确了生态环境质量、敏感性和生态系统服务功能重要性空间分布格局,然后对辽宁省进行了生态功能区划分,并指出了各功能区生态保护与建设的重点和措施以及产业结构调整与优化的对策和方向研究结果表明,在经济和人口增长的长期胁迫作用下,辽宁省生态环境问题依然严峻,主要表现为:土地退化,地表水污染严重,森林质量下降和功能减弱,草地减少与退化并存,天然湿地萎缩,滩涂和海岸带生境恶化,生物多样性面临威胁,农业面源污染凸显,生态系统抗干扰能力下降,生态灾害加剧。全省生态环境质量超过2/3属于一般以下水平,其中优级面积仅占12.56%,良好级面积占18.71%,主要分布在东部及东南部;一般级面积占34.25%,主要分布在中部、北部和南部;较差级面积占34.48%,主要分布在西部及西北部。全省县级市及县有44个,其中生态环境质量为优的仅有4个市县,占总县数的9.09%;生态环境质量为良的有7个市县,占总县数的15.91%;生态环境质量一般的有19个市县,占总县数的43.18%,生态环境质量较差的有14个市县,占总县数的31.82%。全省处于轻度至高度敏感区域。高度敏感区占34.00%,主要分布在辽东山地丘陵、辽东半岛、辽西低山丘陵、辽西北、柳绕地区和大洼县。辽东山地丘陵、辽东半岛和辽西低山丘陵主要是土壤侵蚀高度敏感。辽西北和柳绕地区主要是土地沙漠化高度敏感。大洼县是土壤盐渍化高度敏感。中度敏感区占能.66%,与高度敏感区相间分布。轻度敏感区占3.34%,零星分布在辽东,在辽西和辽河平原也有少量分布。全省生态服务功能均处于比较重要以上。极重要地区占60.66%,基本分布在辽东、辽西和辽河平原的北部与盘锦滨海地区,辽东主要为水源涵养、生物多样性保护、土壤保持、营养物质保持,辽西主要为土壤保持、生物多样性保护、水源涵养、营养物质保持,辽北主要为土壤保持,盘锦滨海地区主要为生物多样性保护。中等重要地区占37.01%,基本分布在辽河平原,在辽东、辽西也有分布,辽河平原主要为土壤保持、水源涵养,沙漠化控制,辽东和辽西主要为土壤保持,辽西北为沙漠化控制。其它地区为比较重要地区,仅占2.33%,主要分布在辽东和辽河平原,在辽西也有少量分布,主要为土壤保持。在生态系统评价的基础上,首先根据地貌和气候划分出4个生态区,即辽东山地丘陵温带湿润半湿润生态区、辽河平原温带半湿润生态区、辽西低山丘陵温带半湿润生态区、辽南环黄渤海海岸带生态区。在明确生态区的基础上,依据生态系统类型与过程的完整性,以及生态服务功能类型的一致性,划分出21个生态亚区。依据生态环境质量、敏感性及生态服务功能重要性等的一致性,进一步划分出52个生态功能区。

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神经节甘脂GD2在正常的组织细胞中很少存在,而在黑色索瘤、小细胞肺癌、等肿瘤细胞表面大量存在。因此能特异性结合神经节营脂GD2,激活肿瘤附近免疫细胞功能的基因工程融合蛋白将为上述肿瘤的治疗开辟新的途径。实验中采用重叠PCR技术,将抗神经节普脂GDZ的单链抗体和抗CD16(FcyRIIIA)分子的单链抗体用(GGGG4s)3和sGGGGs两种连接肤连接,形成两个新型的anti-GD2/anti-CD16单链双特异性抗体基因N1M1和N2M2,将重组基因分别连接表达载体PSE380和pET22b(+),得到重组质粒PSE380-N1M1/pSE380-N2M2和pET22b(+)-N1M1/pET22b(+)-N2M2。psE380-N1M1/pSE380-N2M2转化BL21后诱导表达,表达后的单链双特异性抗体以包涵体的形式存在于细胞中。pET22b(+)-N1M1/pET22b(+)-N2M2转化大肠杆菌BL21(DE3),表达的单链双特异性抗体以可溶形式存在于细胞的周质空问。实验中选择BL21(DE3)/pET22b(+)-N1M1和BL21(DE3)/pET22b(+)-N2M2作为双」亢的生产菌株,经均匀设计优化诱导条件后,两个单链双特异性抗体nlml和n2m2的表达量均可达菌体总蛋白的30%左右,分子量分别为54KD和53KD。实验中选择经过突变改变过的人IL-2(125Ala)与抗GDZ单链抗体触合,构建了副:合蛋白基因IL-2-M,连接表达载体PSE38。,重组质粒转化BI,21菌株,得到工程菌BL21/pSE38O-IL-2-M,诱等农达后,触合蛋白IL-2-m以包涵体的形式存在于细胞中,表达量约占菌体总蛋白的30%,分子量为43KD。IISA分析表明,诱导后表达的融合蛋白可与hIL-2抗体特异性结合。采用Ni-NTA亲和层析和分子筛层析纯化上述三种融合蛋自,纯度可达95%以上。用LDH法检测其对肿瘤的杀伤作月」,实验结果证明:实验构建的中.链双特异性抗体nlml和112m2均可以激活单个核细胞(PBMC),杀伤GDZ阳性肿瘤细胞:IL-2与抗GDZ单链抗体融合蛋白IL-2-m对GD2阳性肿瘤细胞也起到一定的杀伤作用;anti-GD2/anti-CD16单链双特异性抗体与融合蛋白IL-2-m联用效果史为显著。

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长白山岳桦云冷杉林是我国北部亚高山地段罕见的森林植被之一。林下有大量的倒木。倒木株数和生物量分别为509株/ha和33.82吨/ha,主要以鱼鳞云杉为主,多数处于中度腐烂时期。在这种森林中,由于林地苔藓,草本植物对幼苗的竞争以及雨季水湿对种子,苗木的胁迫,所以倒木是该森林的主要苗床。虽倒木的覆盖面积只占林地面积的7.21%,但其上所着生的幼苗株数却占林内幼苗总数的82.45%。倒木只有腐烂至一定程度,而表层的苔藓又不至于达到对幼苗造成胁迫时,才是好的苗床。一般地倒木表层腐殖质的厚度是和倒木的腐烂程度一致的。只有表面腐殖质较厚的大直径腐朽木适合于种子发芽和幼苗生长,所以这里将腐烂倒木的覆盖面积定义为“倒木对更新的有效面积”,它和“倒木分布均匀度”共同影响森林的天然更新。除倒木外、根桩、腐烂根盘堆、林地等也是林下幼苗的更新基质。随着幼苗的生长,自然稀疏开始。在从幼苗到幼树及成树的发展过程中,各树种在不同基质上的株数以不同的指数模式减少。尽管生长于倒木上的植株,在苗期有相对较高的死亡率,但和生长于其它基质上的植株数相比,倒木上着生的树木始终占大多数。倒木上的植株不仅苗期数量大,而且成林率高。

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本文从不同供水、供服条件和耕作措施分别研究分析了试验年份辽宁西部半干旱地区春玉米的水分利用效率(WUE)及其提高途径。结果表明,冬灌可增补冻层储水,保证作物出苗和营养生长对水分的需求;在相对多雨的试验年份,不同供水处理的春玉米,其水分利用效率差异不大,但在春玉米的产品形成期——灌浆期灌水,可提高产量和水分利用率,与不灌相比,水分利用率由21.84提高到22.95kg/mm.ha.增施氮肥和磷肥可显著提高产量,但耗水量仅略有增加,因而提高了水分利用效率,与对照相比,水分利用效率由19.54提高到22.56kg/mm.ha;在施氮肥、磷肥基础配合施用有机肥,可进一步提高产量,达12210kg/ha,水分利用率为23.14kg/mm.ha,这主要是由于提高了春玉米对土壤储水的利用率。此外,合理的耕作措施在一下程度上也可提高水分利用效率。综上所述,补充供水和增施肥料是辽西地区提高作物水分利用效率直接而有效的途径;为充分利用有限的水资源,补充供水的最优选择应是土壤结冻前的优质冬灌和作物需水关键期的苗灌;增施肥料应重视施用磷肥和有机肥;在冬灌基础上进行麦秸覆盖和覆膜播种可进一步提高水分利用效率。

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链霉菌是十分重要的一类放线菌,绝大多数的抗生素都由该类细菌产生。毛壳属真菌是一类重要的丝状真菌,从中也发现有很多结构新颖、活性独特的活性物质。因此本论文对两株链霉菌的活性成分及一株金毛壳菌的次生代谢产物进行了研究。 1.从吸水链霉菌(Streptomyces hygroscopicus 1.358)液态发酵产物(乙酸乙酯提取物)中分离得到3个化合物,通过波谱方法鉴定为RK955A (1)、Nigericin(2)、Elaiophylin(3)。以青霉素耐药-金黄色葡萄球菌作为指示菌的抗菌活性测定表明,三者均具有较强抗菌活性。 2.通过抗肿瘤体外活性筛选模型筛选得到得到一株链霉属土壤放线菌,从中分离得到六个化合物:苯乙酰胺(4)、苯丙酰胺(5)、肉桂酰胺(6)、3-(N-(甲酰胺基)乙酰基)吲哚(7)、鸟苷磷酸(8)、鸟苷(9)。 3.从金色毛壳菌(Chaetomium aureus)的固态培养物中分离得到13个化合物,利用波谱方法将其鉴定为:金毛壳菌素A(10)、金毛壳菌素B(11)、Eugenetin(12)、Eugenitol(13)、Chaetoquadrin A(14)、Chaetoquadrin B(15)、Chaetoquadrin G(16)、Chaetoquadrin H(17)、Chaetochromin A(18)、Sterigmatocystin(19)、O-methylsterigmatocystin(20)、3β-羟基-麦角甾-5,7,22-三烯(21)和过氧麦角甾醇(22)。 4.综述了聚醚类抗生素的结构、生物合成、生物活性及作用机理。 The genus Streptomyces (Actinomycetes) is an important group of microbe. Most antibiotics known nowdays are discovered from species of Streptomyces. The fungi of the genus Chaetomium have attracted much attention because various kinds of secondary metabolites with diverse bioactivities have been found from them. Thus, the bioactive compounds from two strains of Streptomyces and the secondary metabolites of Chaetomium aureus were investigated. 1. Three compounds were isolated from the ethyl acetate extract of the fermentation broth of Streptomyces hygroscopicus. They are identified to be elaiophylin (1), nigericin (2), and antibiotic RK955A (3) on the basis of their spectroscopic data. Compounds 1-3 possess antibacterial activities against Staphyloccocus aureus. 2. It was found that the extract of the fermented broth of a strain of Actinomycetes could inhibit some tumor cel lines. Separation of the bioactive fraction led to the isolation of six compounds. They were characterized to be phenylacetamide (4), phenylpropylamide (5), trans-cinnamamide (6), 3- (N- (formylmethyl) acetamide) indole (7), guanylicacid (8), and guanosine (9). 3. From the fermented broth of Chaetomium aureus, 13 compounds were isolated for the first time. They were determined to be chaetomiumycin A (10), chaetomiumycin B (11), eugenetin (12), eugenitol (13), chaetoquadrin A (14), chaetoquadrin B (15), chaetoquadrin G (16), chaetoquadrin H (17), chaetochromin A (18), sterigmatocystin (19), O-methylsterigmatocystin (20), 3β-hydroxyergosta-5, 7, 22-triene (21) and peroxy-ergosterol (22). Compounds 10 and 11 are new ones. 4. Structure, biosynthesis, biological activity, and mechanisms of polyether antibiotics were reviewed.

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本学位论文报道了作为传统藏药材广泛使用的西藏产雪莲花化学成分的研究。论文由五章组成,第一章是三种西藏产雪莲花的化学成分的系统分离纯化和结构鉴定;第二章为西藏产雪莲花化学成分的液-质及串联质谱联用分析;第三章提出了以HPLC和TLC为检测方法的雪莲花药材质量标准草案;第四章给出了对西藏产雪莲花挥发油化学成分的气-质联用分析结果;第五章概述了雪莲花的化学成分及药理研究进展。 第一章包括三个部分。第一部分报道了绵头雪莲花(Saussurea laniceps Hand.-Mazz.)全草乙醇提取物化学成分的分离鉴定。采用正相硅胶柱层析及凝胶柱层析等分离方法,从西藏产绵头雪莲花的乙醇提取物中共分离鉴定出15个化合物。其中11个化合物为首次从该植物中分离得到,当中2个化合物系在凤毛菊属植物中首次发现。第二部分报道了水母雪莲花(Saussurea medusa Maxim.)全草乙醇提取物的化学成分。采用正、反相硅胶柱层析及凝胶柱层析等分离方法,共分离鉴定出15个化合物,其中1个为新化合物,另有4个化合物为首次从该植物中分离得到。新化合物结构通过质谱和一维及二维核磁共振等波谱解析方法及碱水解反应确定为巴豆酰基-高车前苷(M-7)。第三部分报道了三指雪莲花 (Saussurea tridactyla Sch.-Bip. ex Hook. f.)全草乙醇提取物的化学成分。采用正相硅胶柱层析及凝胶柱层析等分离方法,共分离鉴定出7个化合物,其中1个化合物为首次从该植物中分离得到。 第二章也包括三个部分。首先是采用液-质联用(HPLC-DAD-ESI-MSn)分析方法,对7个西藏不同产地的三指雪莲花化学成分进行了分析,通过与标准品的 UV和MS数据比较,共鉴定出14个峰,并对其中8个共有成分进行了定量测定。其次是关于八种西藏产雪莲花化学成分的液-质联用(HPLC-DAD-ESI-MSn)分析,通过与标准品的UV和MS数据比较,共鉴定出15个峰,并对其中8个共有成分进行了定量检测。最后通过对八种西藏产雪莲花主要化学成分的多级串联质谱(ESI-MSn)分析,快速、灵敏地鉴定出10个黄酮和3个香豆素化学成分。 第三章同样包括三个部分。首先是以绵头雪莲花中主要香豆素成分东莨菪素和伞形花内酯为对照品,通过TLC定性检测和HPLC含量测定,草拟出较严谨的药材质量标准。其次是将绵头雪莲花、三指雪莲花和雪兔子作为一个药材看待,草拟了以东莨菪素和伞形花内酯的TLC检测为指标的药材质量标准。最后是针对水母雪莲花,以主要黄酮成分芹菜素-7-O-b-D-葡萄糖苷为对照品作TLC检测,并草拟出该药材的质量标准草案。 第四章报道了西藏产雪莲花挥发油的化学成分分析。采用传统水蒸气蒸馏法分别从八种雪莲花全草中提取挥发油,利用气相色谱-质谱联用技术分别从水母雪莲花、绵头雪莲花、槲叶雪莲花、云状雪兔子、拉萨雪兔子、小果雪兔子、雪兔子和三指雪莲花中分别鉴定出83、83、56、34、21、20、24和20个化学成分,分别占其挥发油总量的70.7%、76.0%、82.2%、55.4%、49.7%、70.4 %、76.2%和 76.7%。 第五章为综述,总结和概括了雪莲花的化学和药理研究进展。 The dissertation reports the investigation of the chemical constituents of the genus Saussurea. Quite a lot of species in this genus are traditional Tibetan medicinal plants, and hence have been widely used in traditional Tibetan medicine. This dissertation consisted of five chapters. The first chapter is on the chemical constituents of three Saussurea plants. The second section is about the analysis of chemical constituents of Saussurea plants using HPLC-MS and ESI-MS/MS. In the third chapter, we proposed quality-control standards for the Genus Saussurea based on TLC (thin layer chromatography) and HPLC. The fourth chapter is about chemical compositions of the essential oil from the whole plant of Saussurea plants. The last chapter reviews the research progress of the Genus Saussurea. The first chapter consists of three parts. The first part is about chemical constituents of ethanol extracts from whole plant of Saussurea laniceps Hand.-Mazz. Fifteen compounds were isolated by column chromatography on normal phase silica gel and Sephadex LH-20. Among them, eleven compounds were isolated from this plant for the first time, and two compounds were isolated from Genus Saussurea for the first time. The second part is about chemical constituents of ethanol extracts from whole plant of Saussurea medusa Maxim. Fifteen compounds were isolated by column chromatography on normal phase, reversed phase silica gel and Sephadex LH-20. Five of them were isolated from this plant for the first time, and there is one new flavonoid glucoside which was identified as 6″-O-crotonoyl-homoplantaginin (M-7) based on the evidence of one- and two-dimensional nuclear magnetic resonance, mass spectrometry analysis, and alkaline hydrolysis reaction. The last part is about chemical constituents of ethanol extracts from whole plant of Saussurea tridactyla Sch.-Bip. ex Hook. f.. Seven compounds were isolated by column chromatography on normal phase silica gel and Sephadex LH-20. There is one compound which was isolated from this plant for the first time. The second chapter consists of three parts. In the first part, we analyzed the chemical constituents of S. tridactyla collected from seven different places in Tibet using HPLC-DAD-ESI-MSn. Fourteen peaks in the HPLC were identified by comparison of UV and MS spectra with those of authentic compounds, among which eight common peaks were quantified. In the second part, we analyzed the chemical constituents of eight Saussurea species using HPLC-DAD-ESI-MSn method. Fifteen peaks in the HPLC were identified by comparison of UV and MS spectra with those of authentic compounds and eight main peaks of them were quantified. In the last part, we analyzed the chemical compounds of the above eight Saussurea plants directly by ESI-MS/MS. Thirteen major compounds, including 10 flavonoids and 3 coumarins were easily rapidly identified. The third chapter consists of three parts. In the first part, we proposed a comparative high quality-control standard for S. laniceps, based on quality detection by TLC and quantity analysis by HPLC using two major compounds (umbelliferone and scopoletin) as standard compounds. In the second part, in viewing S. laniceps, S. tridactyla and S. gossypiphora as the members of one family of medicinal herbs, we suggested a quality-control standard based on the TLC detection of the two major compounds (umbelliferone and scopoletin). In the last part, we proposed a quality-control standard for S. medusa based on the TLC detection of its major component (apigenin 7-O-glucoside). The four chapter analyzed the chemical constituents of essential oil of eight Saussurea species. The essential oils were extracted from the whole plants of these samples with water stream distillation. By GC-MS analysis, we identified eighty-three compounds from S. medusa, eighty-three from S. laniceps, fifty-six from S. quercifolia, thirty-four from S. aster, twenty-one from S. kingii, twenty from S. simpsoniana, twenty-four from S. gossypiphora, and twenty from S. tridactyla respetively, which accounted for 70.7%, 76.0%, 82.2%, 55.4%, 49.7%, 70.4 %, 76.2% and 76.7% of the total essential oil, respectively. The last chapter reviews the research progress of the Genus Saussurea.