946 resultados para Woodwardia japonica


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三峡库区一些污染严重的工业企业是当地主要的点源污染源,对周围植物群落产生了巨大危害,而植物是生态系统赖以存在的基础,它的生长发育直接影响到生态系统的结构及其正常功能的实现。本研究按照与点源污染源的距离为梯度,通过在三峡库区兴山县白沙河磷化工厂周围布设了32个植物群落固定样地,并以点源污染无法影响到的植物群落为对照,进行样地的野外群落学调查;在每个样地取不同种植物叶片100克左右和样地0~20cm土壤500克,以石灰滤纸法同步进行大气氟化物的取样。样品带回室内应用氟离子选择电极法,测定大气氟化物含量、植物叶片氟的累积量和土壤水溶性氟的含量。同时在野外调查时使用PAM2100叶绿素荧光仪测定植物最大光化学效率即Fv/Fm的值。通过野外调查试验和相关的室内分析,研究了(1):点源污染对三峡库区陆生植物群落组成和物种多样性的影响;(2):点源污染中的主要污染物对植物及土壤环境的影响;(3):不同物种叶片最大光化学效率Fv/Fm对污染胁迫响应的差异。结果如下: 点源污染对植物群落物种丰富度以及Pielou均匀度指数均有不同程度的影响,对于群落结构相对简单的马尾松林和柏木林的不利影响更为显著。相对于污染区来说,对照区中物种重要值的集中程度有所下降。许多物种的重要值在污染区与对照区有明显的变化。马尾松(Pinus massoniana)、檵木(Loropetalum chinense )、铁仔(Myrsine africana)、卷柏(Selaginella tamariscina )等对照区重要值较污染区为高,黄檀(Dalbergia hupeana )、菱叶海桐(Pittosporum truncatum)、君迁子(Diospyros lotus)等污染区的重要值较对照区为高。群落中有些物种比如柏木(Cupressus funebris)的天然更新也受到污染的影响。 污染区土壤pH值大多低于对照区,但是与离污染源距离的相关性不强。污染区有些物种比如马尾松、柏木等叶片中的全氟含量与大气中氟化物的含量和土壤水溶性氟含量明显正相关。但是另外有些物种氟的累积量受点源污染的影响不显著,比如菱叶海桐、翅柃(Eurya alata)等在污染严重的样地内生存状况仍然很好。 在距离点源污染近的样地内,大多数物种的最大光化学效率Fv/Fm的值显著下降。栓皮栎(Quercus variabilis)、马尾松和柏木等的Fv/Fm值与距污染源的距离呈明显的正相关,都是随着离污染源越来越近而逐渐降低。根据污染区相对对照区Fv/Fm值下降幅度的不同,把植物划分为三种类型:对污染敏感型如柏木、铁仔、檵木等,中等敏感型如油桐(Vernicia fordii)、香叶树(Lindera communis)和不敏感型如山胡椒(Lindera glauca)和 蝴蝶花(Iris japonica)等。

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忍冬(Lonicera japonica Thunb.)属忍冬科忍冬属,是一种重要的药用植物,其花蕾称为金银花(Flos Lonicerae),在我国已有1000多年的药用历史,具有清热解毒、凉散风热等功效。我们利用秋水仙素诱导二倍体“大毛花”品种茎尖选育出同源四倍体“九丰一号”品种,并在生产中发现花蕾产量显著提高,而药效成份含量是否发生变化了呢?四倍体忍冬表现出典型的器官巨大性,这些变化是否与其较强生态适应性之间存在联系呢?染色体加倍增强了忍冬的生态适应性,其生态修复功能如何呢?在本研究中,主要从以下几个方面进行了探讨:(1)染色体加倍对其叶片,茎、花蕾和花蕾产量及其药效成份等生物学性状的影响;(2)染色体加倍后植物对水分胁迫的响应;(3)染色体加倍后植物对热胁迫的响应;(4)除上述两个品种外,增加一个变异品种“红银花”,探讨3个忍冬品种对退化生态系统的修复功能。主要结果如下: 1. 通过测定根尖细胞染色体数目和使用流式细胞仪分析茎尖细胞DNA含量,表明四倍体忍冬(2n = 4x = 36)确实来自二倍体忍冬(2n = 2x = 18)的染色体加倍。四倍体忍冬气孔细胞大小显著大于二倍体,而气孔密度显著低于二倍体。四倍体忍冬没有光合“午休”,而二倍体存在明显的光合“午休”,这可能与其存在抗高温的叶片解剖结构特性有关。四倍体忍冬叶片较二倍体变大、变厚、变浓绿(较高叶绿素含量)。与二倍体相比,四倍体忍冬单位叶面积重量显著增高,表明其具有较强的生态适应性。四倍体忍冬单个花蕾的鲜重和干重均显著大于二倍体。连续3年的花蕾产量调查表明,四倍体显著高于二倍体。染色体加倍使其茎干粗壮、节间变短、新梢上着生花蕾数目增多及单个花蕾变大,这是其花蕾高产的生物学基础。对金银花的药效成份而言,染色体加倍不影响绿原酸的含量,但增加了木犀草苷的含量。结果表明,染色体加倍能增加金银花的产量和药效成份的含量,建议四倍体忍冬在药材生产中推广应用。 2. 水分胁迫显著降低二倍体和四倍体忍冬叶片的净光合速率、气孔导度和蒸腾速率。水分胁迫也降低电子传递速率、光系统II实际量子产量和光化学猝灭,而增加非光化学猝灭、总可溶性糖、脯氨酸和丙二醛的含量。四倍体忍冬对水分胁迫的响应表现为其叶片水势、气体交换、叶绿素荧光和有关代谢物含量的变化程度低于二倍体,并且复水后其恢复能力快于二倍体,表明染色体加倍增强了忍冬的抗旱能力。分析其主要原因,可能是由于四倍体植株总叶面积减少、单位叶面积重量增加、叶片表皮细胞和栅栏组织增大以及叶片表皮毛较浓密等形态解剖结构特性有关。结果表明,染色体加倍能增加忍冬植物的抗旱能力,而使其具有较强的生态适应性。 3. 二倍体和四倍体忍冬受48 ºC热胁迫处理6 h和恢复10 h,以及离体叶片45 ºC,50 ºC,55 ºC 水浴热胁迫3 min,应用叶绿素荧光成像系统研究了它们对热胁迫的响应。热胁迫显著降低了两个品种叶片的最大光化学效率、电子传递速率、光系统II实际量子产量和光化学猝灭,降低了四倍体的非光化学猝灭,而增加了二倍体的非光化学猝灭。热胁迫增加了两个品种叶片的总可溶性糖、脯氨酸和丙二醛的含量。四倍体受热胁迫的叶绿素荧光参数和有关代谢物的响应程度低于二倍体,以及其恢复程度快于二倍体,表明染色体加倍提高了抗热性。此外,叶绿素荧光成像的异质性也表明,四倍体的抗热能力大于二倍体。进一步的叶片解剖结构分析表明,四倍体叶片的表皮细胞变大、栅栏组织增厚、表皮毛较浓密等特点,是其抗热性强的主要原因。 4.根据以上的研究结果,通过四倍体忍冬生态修复功能的野外试验证明染色体加倍后其生态适应性变化。在本研究中,针对北京市门头沟区大面积不同类型的废弃地急需恢复植被和景观的问题,在恢复生态学理念的指导下,综合运用集成技术,将3个忍冬品种植物用于这些退化生态系统的恢复。在王平镇的公路下边坡(以碎石和矿渣为主)、煤矿、石灰窑和采石场4种类型废弃地建立生态修复的试验示范区。结果表明,在4个废弃地类型上引进的3个金银花品种,具有使示范区快速复绿、当年成景和群落快速形成的潜力,并具有对不同退化迹地的适应能力和恢复效果,其中四倍体忍冬效果更好些,这主要与其形态解剖结构和较强的生态适应性有关。

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Microalgae play an important role in conditioning water quality for penaeid larval culture. Recently it has been demonstrated that a modification of the green water larval culture system (Ling, 1969) for Macrobrachium allows the production of post larvae without any water change, despite extensive use of artificial feeds (Ang and Cheah, 1986). Increase of toxic metabolites such as ammonia and nitride are also common in penaeid larval culture, especially where excessive amounts of artifial feeds are employed. Present work examines the use of six marine microalgae at four cell concentrations as a "biological filter" system, to control and detoxify levels of ammonia and nitrite in P. monodon larval culture water whilst using artificial diet. Preliminary results indicate that amongst the six algal species tested, C. japonica at 1000 cell μlˉ¹ was most effective in reducing accumulated toxic metabolites from an unchanged culture water environment.

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The monthly average temperatures at Puttalam Lagoon, Dutch Bay, Portugal Bay towards Kovilmunai and Portugal Bay towards Pallugaturai showed a distinct annual cycle. The peak was in April and values gradually fell till September. There was a further gradual fall in temperature from October to January. The highest temperatures in all four stations were in April. The highest salinities in all the stations were from May to October i.e., during the south-west monsoon. The salinities at Dutch Bay and Portugal Bay were high in March and April corresponding to the highest temperatures reached during these months. Two maxima have been observed in phytoplankton production. A primary maximum in May-June and a secondary maximum in October. The primary and secondary maxima are due to the influx of nutrient laden waters from the rivers Kal Aru and Pomparippu Aru. The phytoplankton producing blooms were Rhizosolenia alata. Rhizosolenia imbricata, Chaetoceros lascinosus, Chaetoceros pervianus, Ch,aetoceros diversus, Coscinodiscus gigas, Thallasionema nitzschioides, Thalassiosira subtilis, Thallassiothrix frauenfeldii, Asterionella japonica, Sceletonema costatum, Bacteriastrum varians and Biddulphia sinensis. Sudden outbursts of a single species were common. These diatoms were species of Chaetoceros and Rhizosolenia, and Thallassiothrix frauenfeldii. Wide fluctuations have been observed in the distribution of phytoplankton but no definite conclusions can be drawn as the period of observation was only one year.

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PLEASE ALSO CHECK THE FULL TEXT ABSTRACT. Toxin production and toxin profiles of four Raphidophytes grown under different salinities were compared to investigate the influence of salinity on cellular content of neurotoxin. In Chatonella andqua CaTx-1, CaTx-11, and CaTx-111 peaked at 25 pplt with yields of 0.99, 0.42, and 2.90 pg/ceU, but the highest yields (2.35 pg/cell) of CaTx-IV was attained at 30 ppt. On the other hand, Chatonella marina yielded higher proportions of CmTx-1 (0.55 pg/ceH) and CmTx-111 (2.50 pg/cell) at 25 ppt. However, CmTx-IV was present in its highest amount (1.65 pg/cell) at 30 ppt, as seen in C anriqua. A smaH amount of CmTx-11 was also detected at 20-35 ppt. The toxin compositions indicate that H. akashiwo is more sensitive to higher salinities than the other three raphidophytes. Substantial compositional change was observed in case of H. akashiwo. HaTx-11 (corresponding to PbTx-9) was detected only as a trace at 20 and 25 ppt. Toxin HaTx-IV (corresponding to oxidized PbTx-2) was most dominant and peaked at 20 ppt with a yield of 0.3 pg/cell. Considerable amounts of HaTx-1 and III (corresponding to PbTx-2 and 3) were also detected. At higher salinities of above 25 ppt HaTx-11 was not detected. F. japonica gave highest yields of FjTx-11 (PbTx-2) and FjTx-IV (Oxidized PbTx-2) at 20 ppt with yields of 0.95, 1.54 pg/cell while the production of toxic profiles FjTx-1 (PbTx- 1) and FjTx-111 (PbTx-3) peaked at 25 ppt with yields of 0.99, 2.54 pg/ceU. A sharp decrease in all toxins profiles (CaTx, CmTx, HaTX and FjTx) was found at salinities of above 30 ppt.

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We report improved whole-genome shotgun sequences for the genomes of indica and japonica rice, both with multimegabase contiguity, or almost 1,000-fold improvement over the drafts of 2002. Tested against a nonredundant collection of 19,079 full-length cDNAs, 97.7% of the genes are aligned, without fragmentation, to the mapped superscaffolds of one or the other genome. We introduce a gene identification procedure for plants that does not rely on similarity to known genes to remove erroneous predictions resulting from transposable elements. Using the available EST data to adjust for residual errors in the predictions, the estimated gene count is at least 38,000 - 40,000. Only 2% - 3% of the genes are unique to any one subspecies, comparable to the amount of sequence that might still be missing. Despite this lack of variation in gene content, there is enormous variation in the intergenic regions. At least a quarter of the two sequences could not be aligned, and where they could be aligned, single nucleotide polymorphism ( SNP) rates varied from as little as 3.0 SNP/kb in the coding regions to 27.6 SNP/kb in the transposable elements. A more inclusive new approach for analyzing duplication history is introduced here. It reveals an ancient whole-genome duplication, a recent segmental duplication on Chromosomes 11 and 12, and massive ongoing individual gene duplications. We find 18 distinct pairs of duplicated segments that cover 65.7% of the genome; 17 of these pairs date back to a common time before the divergence of the grasses. More important, ongoing individual gene duplications provide a never-ending source of raw material for gene genesis and are major contributors to the differences between members of the grass family.

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This project was done for identifying the mesopelagic fish of the Iranian waters of Oman Sea, during two year from 2008 to 2010. The specimens were collected using two trawler vessel from nine station. All the specimens were fixed in formalin then in 70% alcohol and carried to the laboratory. In total of 19 species belonged to 14 families of 6 orders identified including: Echinorhinidae, Stomidae, Phosichthyidae, Synodontidae, Paralepididae, Myctophidae, Acropomatidae, Priacanthidae, Pentacerotidae, Champsodontidae, Gempylidae, Trichiuridae, Nomeidae and Congridae. Of which 17 species were identified up to species level including: Echinorhinus brucus, Bathophilus indicus, Chauliodus sloani, Harpadon nehereus, Lestrolepis japonica, Benthosema pterotum, Diaphus garmani, Diaphus effulgens, Bolinichthys photothorax, Acropoma japonicum, Synagrops adeni, Cookeolus boops, Histiopterus typus, Champsodon sagittus, Neoepinnula orientalis, Trichiurus lepturus, Cubiceps baxteri. Vinciguerria was identified up to genus level because only one specimen caught during the survey and one species (Congridae) was identified up to family level because only 3 specimens of this fish in early stage of life were caught and their characters were not suitable for identify up to species level. The highest species belong to Myctophidae family of Myctophiformes order.

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<正> 近年来,在我国福建省养鳗场,发生一种新的鳗鲡(Anguilla japonica)流行病。虽然此病不像细菌性的爱德华氏病(Edwardsielliasis)那样普遍。但一旦发生此病,全场鳗鲡就毁灭性地死亡。使养鳗者经济蒙受严重损失。这种情况,不得不引起鱼病工作者关注。1991年7月,在福建省“S”养鳗场暴发此病,死亡严重。我们把病鳗(尚未死亡)空运回本所实验

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<正> 一. 绪言我国池塘养鱼事业有着悠久的历史,饲养的种类有鱿(草鱼),青、鲢、鳙、鲤、鳊、鲮等,通常称为“家鱼”,而生长在池塘里的其它鱼类如刺鳅(Mastacembelus aeuleatus),黄鳝(Monopiterus albus),鳗鲡(Anguilla japonica),鲫(Carassius auratus),麦穗鱼(Pseudorasbora parva),白鲦(Hemiculter laucisculus),赤眼鳟(Squaliobarbus curri-culus),(Elopic

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The infra- and component communities of intestinal helminths of carp Cyprinus carpio were investigated in six lakes in the flood plain of the lower and middle reaches of the Yangtze River, China. Eight species of helminth parasites were recorded. The intestinal helminth communities were species rich in Niushan and Tonghu lakes where the digenean Asymphylodora japonica was the dominant species, whereas in Qinggang and Yanglan lakes a species-poor helminth community had only one species, Khawia sinensis. The degree of similarity within localities was highest in Qinggang and Yanglan lakes, and was high between communities where K. sinensis was the dominant species. The rich composition of these helminth communities may be because China is the heartland for carp while the poor helminth composition of those in Qinggang and Yanglan lakes may reflect the poor fauna there. It is suggested that species compositions of intestinal helminth communities of carp may be diversified in lakes in the hood plain of the Yangtze River. (C) 1999 The Fisheries Society of the British Isles.

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对采集自我国不同地区、不同森林生态类型中的,以及现保存于中国科学院沈阳应用生态研究所东北生物标本馆(IFP)、中国科学院微生物研究所真菌标本馆(HMAS)等国内主要标本馆的非褶菌目木材白色腐朽菌,小薄孔菌属(Antrodiella Ryvarden & I. Johans.)、耙齿菌属(Irpex Fr.)、容氏菌属(Junghuhnia Corda. emend. Ryvarden)和齿耳属(Steccherinum Gray)四属真菌标本进行了全面系统的研究。按照现代分类学方法对四属白腐菌进行详细的描述和显微结构绘图,记载了每种的寄主、国内分布及研究标本,并对每种与其相似种的联系和区别进行了讨论。我国范围内共记录及描述小薄孔菌属(Antrodiella)15种,耙齿菌属(Irpex)2种,容氏菌属(Junghuhnia)7种,齿耳属(Steccherinum)12种。其中,共发现新种4个,分别是:柄生小薄孔菌Antrodiella stipitata H.S. Yuan & Y.C. Dai,柏生小薄孔菌Antrodiella thujae Y.C. Dai & H.S.Yuan,亚圆孢齿耳菌Steccherinum subglobosum H.S. Yuan & Y.C. Dai和尖囊齿耳菌Steccherinum subulatum H.S. Yuan & Y.C. Dai;发现中国新记录种4个,分别是:柔韧小薄孔菌Antrodiella duracina (Pat.) I. Lindblad & Ryvarden,日本容氏孔菌Junghuhnia japonica Núñez & Ryvarden,集刺齿耳菌Steccherinum aggregatum Hjortstam & Spooner和圆孢齿耳菌Steccherinum hydneum (Rick) Maas Geest.。对四属中的代表性种类和重要种类进行了rDNA ITS片段序列测定,利用系统发育分析软件PHYLIP3.6对Antrodiella属和Steccherinum属中的种类进行系统发育分析,并探讨了Antrodiella等上述四属间的系统发育关系。结果表明,与Irpex相比,Junghuhnia和Steccherinum 与Antrodiella具有更近的亲缘关系。Irpex和Steccherinum两个属虽然都具有齿状子实层体结构,但其亲缘关系较远。

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广西壮族自治区是中国多孔菌资源比较丰富的区域之一,本研究对广西主要林区进行了初步调查,并根据形态学研究方法对广西地区的多孔菌进行了系统分类学研究。 结果显示,广西地区的多孔菌共有15科,60属,140种。研究过程中发现两个新种,分别是菌索容氏孔菌Junghuhnia rhizomorpha H.S. Yuan & Y.C. Dai和小孔大孢卧孔菌Megasporoporia microporela X.S. Zhou &Y.C. Dai;发现7个中国新记录种:萨拉氏灵芝Ganoderma sarasinii Steyaert,唐氏胶囊革菌Gloeocystidiellum donkii S.S. Rattan,线浅孔菌Grammothele lineata Berkeley & M.A. Curtis,粉状捷克革菌Jacksonomyces furfurellus (Bres.) Sheng H. Wu & Z.C. Chen,半伏容氏孔菌Junghuhnia separabilima (Pouzar) Ryvarden,非洲纵隔担孔菌Protomerulius africanus (Ryvarden) Ryvarden和日本芮氏孔菌Wrightoporia japonica Núñez & Ryvarden;78种为广西地区新记录种,占该地区已报道种类的55.7%。 依据分类学的研究结果,对广西地区的多孔菌的种类组成和地理成分进行了初步分析,结果显示,优势科为多孔菌科Polyporaceae(33.3%),其次为皱孔菌科Meripilaceae(10%),优势属为多孔菌属Polyporus(7.9%%)和针层孔菌属Phellinus(5.7%);属的地理成分以世界广布属(68.3%)和热带–亚热带分布属(23.3%)为主,种的地理成分以泛热带分布成分(35%)和世界广布种(30%)为主。 经研究表明广西地区共有森林干基腐朽病原多孔菌21种,食用多孔菌菌有5种,药用多孔菌32种,工业用多孔菌17种,多孔菌资源较丰富。 对重要种类木蹄层孔菌Fomes fomentarius (L.:Fr.) Fr.进行了固体培养研究,结果显示木蹄层孔菌的营养菌丝生长最适培养温度为28℃,最适培养pH值为7,最适培养碳源为蔗糖,最适培养氮源为蛋白胨。

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本文采用热解吸与气相色谱联用技术对沈阳市主要绿化树种银中杨(Populus alba × berolinensis)、垂柳(Salix babylonica)、榆树(Ulmus pumila)、皂角(Gleditsia japonica)、丁香(Syringa oblate)和水腊(Ligustrum obtusifolium)植物源挥发性有机物(Biogenic Volatile Organic Compounds,BVOCs)排放的日变化、季节变化规律进行了观测,并估算了这6种树的BVOCs排放通量;同时采用开顶箱法研究了高浓度CO2(700 µmol•mol-1)、O3(80 nmol•mol-1)及二者复合作用下蒙古栎(Quercus mongolica)和油松(Pinus tabulaeformis)BVOCs排放规律。研究结果如下所示: (1) 6种绿化树种BVOCs的释放具有显著的日变化和季节变化规律,且夜间几乎均不排放异戊二烯。 (2) 不同树种排放的BVOCs组成明显不同,银中杨、垂柳和蒙古栎以排放异戊二烯为主;油松主要释放α-蒎烯;榆树、皂角和丁香以释放柠檬烯为主;水腊在不同时段其BVOCs组成情况变化较大,主要释放异戊二烯、柠檬烯和α-蒎烯;其中银中杨和垂柳的BVOCs释放量明显高于其它树种。 (3) 在实测数据基础上,估算出沈阳市6种主要绿化树种银中杨、垂柳、榆树、皂角、丁香和水腊在自然条件下的BVOCs年排放量分别为104.86tC,168.66tC,3.56tC,1.27tC,4.07tC和1.33tC。 (4) 大气CO2和O3浓度升高条件下,树木BVOCs释放规律和排放物组成受植物种类和生长季的影响;单独提高大气CO2或O3浓度可显著影响树木BVOCs的释放,二者的复合作用对BVOCs释放的影响主要介于两者单独作用的结果之间。

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由于森林生态系统的复杂性,过去常用统计回归模型模拟它的各种动态现象。但这样的模型不能揭示森林生态系统的内在规律,故可称之为“黑箱”模型。随着对森林生态系统认识的加深,以及电子计算机技术的广泛应用,用来模仿森林生态系统内在结构与功能规律的各种计算机模型得到了极大发展,从而产生一些不同“灰化”程度的森林动态“仿真”模型。本文建立的阔叶红松林生长与演替计算模型(DOPIDE)就属于这样的“灰箱”模型。KOPIDE(for KOrean PIne'DEciduous mixed forests)是在JABOWA(Botkin, 1972)和FORET(Shugart等,1977)两个模型的基础上建立的,它们都可称为GAP模型。KOPIDE模型共涉及八个树种:红松(Pinus koraiensis)、水曲柳(Fraxinus mandshurica)、紫椴(Tilia amurensis)、春榆(Ulmus japonica)、蒙古柞(Quercus mongolica)、色木(Acer mono)、白桦(Betula platyphylla)、以及山杨(Populus davidiana)。建立该模型的理论基础是森林演替的林窗(CAP)动态理论,它以一年的步长模拟了样地里每株树木的整个生长发育过成(即更新、生长和枯死)。虽然KOPIDE是JABOWA和FORET的直接效仿模型,但它的模拟针对性较强,在模型的结构上有了很大改进。它的运行结果表明,KOPIDE模型在树种生物学特性的描写上、在阔叶红松林动态规律的模拟上、以及在择伐生长的预测上都有较好的可靠性,可用来揭示阔叶红松林长时期的更新、生长和演替规律与特征,也可模拟阔叶红松林的各种经营方式,为决策人提供预测性结果,以供参考。经过KOPIDE模型的反复运行与调试,发现各树种在更新、枯死与林窗大小的关系上很不相同。根据这种现象,可将树种划分为四类:1、在较大的林窗下更新,枯死后不产生大林窗;2、更新不需要林窗,死亡后产生的林窗较大;3、更新需要林窗条件,枯死后不产生林窗;4、不在林窗下更新,死亡后也不产生林窗。尽管这样的建有点绝对化和简单化,但从中可以得出几类树种之间复杂的相互关系网。由此把复杂森林生态系统大范围的动态变化过程视为组成其许多同质或异质小林地单元的动态相嵌。林地单元的同质性,决定了它们动态变化的同步性,从而导致整个林分动态的突性或不稳定性;而林地单元的异质性是决定森林生态系统稳定性的关键性因素。这从另一角度为在东北东部山地和发展阔叶红松林提供了较有说服力的理论基础。

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干扰素(IFNs)是最早发现的具有广泛用途的一类细胞因子,IFN-α通过JAK/STAT信号途径调控机体一系列生理和病理反应。至今尚未发现类干扰素的小分子。我们前期研究发现天然产物毛蕊异黄酮可激活干扰素诱导的JAK/STAT信号途径。为发现类干扰素小分子、获得小分子探针,本课题拟建立成熟的JAK/STAT信号途径的筛选模型,合成毛蕊异黄酮及其类似物,研究这些化合物的构效关系,进而尝试通过共价键标记生物素或香豆素来直接研究它们与相关受体的作用。 从异香草醛出发经7步合成反应得到了毛蕊异黄酮。采用平行合成策略得到异黄酮类化合物;采用分支式合成策略,以取代苯乙酸作为合成砌块,获得具有与异黄酮类似结构的香豆素、3-芳基喹诺酮。与分离得到的黄酮类化合物,构建了一个包括异黄酮、黄酮、香豆素、3-芳基喹诺酮在内的化合物库。 建立了包含IFN-α刺激反应元件 (ISRE)的荧光素酶报告基因体系,通过筛选化合物库中的化合物,发现异黄酮骨架为激活JAK/STAT信号途径必须结构、毛蕊异黄酮7-位酚羟基被取代后活性丧失。根据以上结果,对毛蕊异黄酮3′-位标记物的合成进行了初步尝试。 发现山茱萸科植物青荚叶(Helwingia japonica (Thunb.) Dietr.)有抑制蛋白酪氨酸磷酸酯酶1B(PTP1B)的活性。从其地上部分95%乙醇提取物的乙酸乙酯部分分离得到5个化合物,应用波谱方法及与已知品对照的手段鉴定它们为p-menth-2-en-1β, 4β, 8-triol (Z-1)、blumenol A (Z-2)、2′,3′,4′,5′,6′-五羟基查尔酮(Z-3)、洋芹素7-O-β-D-吡喃葡萄糖苷(Z-4)、木犀草素7-O-β-D-吡喃葡萄糖苷(Z-5). Interferons (IFNs) are one kind of cytokines with broad functions. IFN-α mediates series physiological and pathological changes of human body via JAK/STAT pathway. Untill now, no IFNs-like small molecules are discovered. In our preliminary experiment, the natural product calycosin has been observed to activate JAK/STAT pathway. Therefore, we establish a luciferase reporter gene system and synthesize calycosin and its analogues to reveal their structure-activity relationship (SAR). Besides, in order to prove that calycosin activates JAK/STAT pathway through IFN receptor, we attempted to tag it with biotin or coumarin by covalent bonding. Calycosin was synthesized from isovanillin via seven steps. Other isoflavones were obtained by parallel synthesis; coumarins and quinolones were prepared through divergent synthesis, using substituted phenylacetic acids as building blocks. Combing with natural flavones, a small molecule library was established. A luciferase reporter gene system, consisting of 5 copies of the ISRE (interferon-stimulated response element), was used for screening of small molecules from that library. We found that the core-structure of isoflavone was necessary, and if the 7-OH is substituted, the activity slumps. According to our observation, we tried to tag biotin or coumarin at 3′-OH of calycosin. The 95% ethanol extract of the aerial parts of Helwingia japonica (Thunb.) Dietr. showed protein tyrosine phosphatase 1B (PTP1B) inhibitory activity. Five compounds were isolated. On the basis of spectral data or by comparison with authentic samples, they were identified as p-menth-2-en-1β,4β,8-triol (1), blumenol A (2), 2′,3′,4′,5′,6′-pentahydroxychalcone (3), apigenin 7-O-β-D-glucopyranoside (4), and luteolin 7-O-β-D-glucopyranoside (5).