生态网络分析的研究进展

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国产凤仙花属的三新种

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昆虫胁迫下的植物应激反应模式

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生态学的精神价值

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以芳香胺玻璃为载体的固定化的胆固醇脂酶和胆固醇氧化酶

Ｉｎｃｒｅａｓｅｄｌｅｖｅｌｏｆｃｈｏｌｅｓｔｅｒｏｌｉｓｆｏｕｎｄｉｎｃｏｒｏｎａｒｙａｒｔｅｒｙｄｉｓｅａｓｅ ,ｎｅｐｈｒｏｓｉｓ,ｄｉａｂｅｔｅｓ,ｍｙｘｏｅｄｅｍａ ,ｏｂｓｔｒｕｃｔｉｖｅｊａｕｎｄｉｃｅａｎｄｈｙｐｏｔｈｙ ｒｏｉｄｉｓｍ ;ｗｈｉｌｅｄｅｃｒｅａｓｅｄｌｅｖｅｌｏｆｃｈｏｌｅｓｔｅｒｏｌｉｓｏｂｓｅｒｖｅｄｉｎｃａｓｅｓｏｆｈｙｐｏｔｈｙｒｏｉｄｉｓｍ ,ａｎｅｍｉａ,ｍａｌａｂｓｏｒｐｔｉｏｎａｎｄｗａｓｔｉｎｇｓｙｎｄｒｏｍｅｓ[1] .Ｔｈｕｓ,ｃｈｏｌｅｓｔｅｒｏｌｄｅｔｅ…     

黄土高原的土壤水分利用与生态环境的关系

黄土高原的土壤水分利用与生态环境的关系韩仕峰,黄旭（中国科学院西北水土保持研究所,陕西杨陵７１２１００）（水利部西北水土保持研究所,陕西杨陵７１２１００）ＲｅｌａｔｉｏｎｓｈｉｐＢｅｔｗｅｅｎＳｏｉｌＷａｔｅｒＵｔｉｌｉｚａｔｉｏｎａｎｄＥｃｏｌｏｇｉｃａｌＥｎｖｉｒｏｎｍｅｎｔｉｎｔｈｅＬｏｅｓｓＰｌａｔｅａｕ￥ＨａｎＳｈｉｆｅｎｇ;ＨｕａｎｇＸｕ（ＮｏｒｔｈｗｅｓｔｅｒｎＩｎｓｔｉｔｕｔｅｏｆＳｏｉｌａｎｄＷａｔｅｒＣｏｎｓｅｒｅａｔｉｏｎ,ＡｃａｄｅｍｉａＳｉｎｉｃａ,Ｙａｎｇｌｉｎｇ,ＳｈａａｎｘｉＰｒｏｖｉｎｃｅ７１２１００）．ＣｈｉｎｅｓｅＪｏｕｒｎａｌｏｆＥｃｏｌｏｇｙ,１９９３,１２（１）：２５－２８。Ｉｔ＇ｓｃｏｎｓｉｄｅｒｅｄｂｙｔｈｅａｕｔｈｏｒｓｔｈａｔｔｈｅｒｅａｒｅｔｈｒｅｅｋｉｎｄｓｏｆｐｒｏｂｌｅｍｓｉｎｕｔｉｌｉｚａｔｉｏｎｏｆｓｏｉｌｗａｔｅｒｒｅｓｏｕｒｃｅｓｉｎｔｈｅＬｏｅｓｓＰｌａｔｅａｕ：１．ｆｏｒｍａｔｉｏｎｏｆａｄｅｆｉｎｉｔｅｔｈｉｃｋｎｅｓｓｏｆｄｒｙｓｏｉｌｌａｙｅｒｄｕｅｔｏｉｎｔｅｎｓｉｖｅｗａｔｅｒａｂｓｏｒｐ－ｔｉｏｎａｎｄｃｏｎｓｕｍｐｔｉｏｎ     

鼎湖山土壤的微生物及其对酸度的适应特征

鼎湖山土壤的微生物及其对酸度的适应特征葛荣盛（广东省土壤研究所广州５１０６５０）ＳｏｉｌＭｉｃｒｏｂｃｓａｔＤｉｎｇｈｕｓｈａｎＮａｔｕｒａｌＲｅｓｅｒｖｅａｎｄＴｈｅｉｒＡｄａｐｔａｂｉｌｉｔｙｔｏＡｃｉｄｉｔｙ￥．ＧｅＲｏｎｇｓｈｅｎｇ（Ｇｕａｎｇ－ｄｏｎｇＩｎｓｔｉｔｕｔｅｏｆＳｏｉｌＳｃｉｅｎｃｅｓ,Ｇｕａｎｇｚｈｏｕ５１０６５０）．ＣｈｉｎｅｓｅＪｏｕｒｎａｌｏｆＥｃｏｌｏｇｙ,１９９３,１２（３）：１１－１８．ＴｈｉｓｐａｐｅｒｄｉｓｃｕｓｓｅｓｔｈｅｍｉｃｒｏｆｌｏｒａｅｉｎｓｏｉｌｓｕｎｄｅｒｄｉｆｆｅｒｅｎｔｆｏｒｅｓｔｔｙｐｅｓａｔＤｉｎｇｈｕｓａｎｎａｔｕｒａｌｒｅｓｅｒｖｅａｎｄｔｈｅｉｒａｄａｐｔａｂｉｌｉｔｙｔｏａｃｉｄｉｔｙ：１．Ｕｎｄｅｒｍｉｘｅｄｆｏｒｅｓｔ,ａｍｍｏｎｉｆｙｉｎｇＢａｃｔｅｒｉａ,ｃｅｌｌｕｌｏｓｅ－ｄｅｃｏｍｐｏｓｉｎｇｂａｃｔｅｒｉａａｎｄＯｌｉｇｏｎｉｔｒｏｐｈｉｌｅｓａｒｅｄｏｍｉｎａｎｔ;ｕｎｄｅｒｂｒｏａｄｌｅａｖｅｄｆｏｒｅｓｔ,ｃｅＩｌｕｌｏｓｅ－ｄｅｃｏｍｐｏｓｉｎｇｆｕｎｇｉａｒｅｍｏｒｅ;ａｎｄｌｉｔｔｌｅｄｉｆｆｅｒｅｎｃｅｃａｎｂ     

落叶松人工林土壤肥力变化的研究

落叶松人工林土壤肥力变化的研究阎德仁（内蒙古林业科学研究院呼和浩特市０１００１０）ＳｏｉｌＦｅｒｔｉｌｉｔｙＶａｒｉａｔｉｏｎｓＵｎｄｅｒＡｒｔｉｆｉｃｉａｌＬａｒｃｈＦｏｒｅｓｔ￥．ＹａｎＤｅｒｅｎ（ＦｏｒｅｓｉｒｙＩｎｓｔｉｌｕｔｅｏｆＩｎｎｅｒＭｏｎｇｏｌｉａ,Ｈｕｈｈｏｔ０１００１０）．ＣｈｉｉｎｅｓｅＪｏｕｒｎａｌｏｆＥｃｏｌｏｇｙ,１９９３,１２（３）：８－１０．Ｔｈｉｓｐａｐｅｒｓｔｕｄｉｅｓｔｈｅｖａｒｉａｔｉｏｎｏｆｓｏｉｌｆｅｒｔｉｌｉｔｙｕｎｄｅｒｐｕｒｅａｒｔｉｆｉｃｉａｌｌａｒｃｈ（Ｌａｒｉｘｇｍｅｌｉｎｉｉ）ｆｏｒｅｓｔｆｒｏｍａｓ－ｐｅｃｔｓｏｆｓｏｉｌｈｕｍｕｓａｎｄｅｎｚｙｍｅａｃｔｉｖｉｔｙ．Ｗｉｔｈｉｎｃｒｅａｓｉｎｇａｇｅｏｆｆｏｒｅｓｔｓｔａｎｄ,ｓｏｉｌｆｅｒｔｉｌｉｔｙｔｅｎｄｓｔｏｄｅ－ｃｒｅａｓｅ,ｂｕｔｓｏｉｌｅｎｚｙｍｅａｃｔｉｖｉｔｙｔｅｎｄｓｔｏｉｎｃｒｅａｓｅ．Ｕｎｄｅｒｆｏｒｅｓｔｗｉｔｈ２０ｙｅａｒｓｏｆａｇｅ,ｔｈｅｃｏｎｔｅｎｔｓｏｆｓｏｉｌｈｕｍｕｓ,ｈｕｍｉｃａｃｉｄａｎｄｆｕｌｖｉｃａｃｉｄａｎｄｔｈｅｒａｔｉｏｏｆｈｕｍｉｃａｃｉｄ     

空气污染对植物病虫害的影响

空气污染对植物病虫害的影响吴亚,金翠霞（江苏省农科院植物保护研究所,南京２１００１４）ＥｆｆｅｃｔｓｏｆＡｔｍｏｓｐｂｅｒｉｃＰｏｌｌｕｔｉｏｎｏｎＰｌａｎｔＤｉｓｅａｓｅｓａｎｄＰｅｓｔｓ￥ＷｕＹａ;ＪｉｎＣｕｉｘｉａ（ＩｎｓｔｉｔｕｔｅｏｆＰｌａｎｔＰｒｏ－ｔｅｃｔｉｏｎ,ＪｉａｎｇｓｕＡｃａｄｅｍｙｏｆＡｇｒｉｃｕｌｔｕｒａｌＳｃｉｅｎｃｅｓ,Ｎａｎｊｉｎｇ２１００１４）．ＣｈｉｎｅｓｅＪｏｕｒｎａｌｏｆＥｃｏｌｏｇｙ,１９９３,１２（６）：４９－５３．Ｔｈｉｓｐａｐｅｒｓｕｍｍａｒｉｚｅｓｔｈｅｅｆｆｅｃｔｓｏｆｍａｉｎａｔｍｏｓｐｈｅｒｉｃｐｏｌｌｕｔａｎｔｓ,ｓｕｃｈａｓＯ＿３,ＳＯ＿２,ｆｌｕｏｒｉｄｅｓ,ａｃｉｄｒａｉｎｅｔｃ．ｏｎｐｌａｎｔｐａｔｈｏｇｅｎｉｃｍｉｃｒｏｏｒｇａｎｉｓｍｓ;ｔｈｅｅｆｆｅｃｔｓｏｆａｉｒｐｏｌｌｕｔｉｏｎｏｎｔｈｅｏｃｃｕｒａｎｃｅａｎｄｉｎｆｅｓｔａｔｉｏｎｏｆｐｈｙｔｏｐｈａｇｕｓｉｎｓｅｃｔｓ,ａｎｄｔｈｅｉｎｆｌｕｅｎｃｅｓｏｆｇｒｅｅｎｈｏｕｓｅｅｆｆｅｃｔｏｆＣＯ＿２ｏｎｔｈｅｏｕｔｂｒｅａｋｏｆｐｅｓｔｓ。Ｋｅｙｗｏｒｄｓ：ａｔｍｏｓｐｈｅｒｉ     

肿柄菊的化学成分

Ｔｉｔｈｏｎｉａｄｉｖｅｒｓｉｆｏｌｉａ (Ｈｅｍｓｌ.)Ａ .Ｇｒａｙ (Ｃｏｍｐｏｓｉｔａｅ)ｉｓａｎＡｍｅｒｉｃａｎｐｌａｎｔｗｈｉｃｈｈａｓｂｅｃｏｍｅｎａｔｕｒａｌｉｚａｔｉｏｎｉｎｔｈｅｓｏｕｔｈｏｆＣｈｉｎａ .ＩｎＹｕｎｎａｎ ,ｉｔｉｓｍａｉｎｌｙｄｉｓｔｒｉｂｕｔｅｄｏｎｓｍａｌｌｈｉｌｌｓｏｆｔｏｒｒｉｄｚｏｎｅｗｉｔｈａｎａｌｔｉｔｕｄｅｆｒｏｍ 5 0 0ｔｏ 1 6 0 0ｍｅｔｅｒｓａｂｏｖｅｓｅａｌｅｖｅｌ.Ｔｈｅｌｅａｖｅｓｈａｖｅｂｅｅｎｕｓｅｄａｓａｎａｇｅｎｔｆｏｒｓｕｂｄｕｉｎｇｓ…     

Photoregulation of seed germination of wild-type and of an aurea-mutant of tomato

Seed germination of an aurea mutant of tomato ( Lycopersicon esculentum Mill.) is promoted by continuous irradiation with red, far-red or long-wavelength far-red (758 nm) light as well as by cyclic irradiations (5 min red or 5 min far-red/25 min darkness). Far-red light applied immediately after each red does not change the germination behaviour. Seed germination of the isogenic wild-type, cv. UC-105, is promoted by continuous and cyclic red light while it is inhibited by continuous and cyclic far-red light and by continious 758 nm irradiation. Far-red irradiation reverses almost completely the promoting effect of red light. The promoting effect (in the aurea mutant) and the inhibitory effect (in the wild-type) of continuous far-red light do not show photon fluence rate dependency above 20 nmol m⁻² s⁻¹. It is concluded that phytochrome controls tomato seed germination throgh low energy responses in both the wild type and the au mutant. The promoting effect of continuous and cyclic far-red light in the au mutant can be attributed to a greater sensitivity to P_fr.     

六种藓类植物茎的比较解剖学研究

通过对6种藓类植物,即褶叶青藓(Brachythecium salebrosum(Web.et Mohr.)B.S.G.)、湿地匐灯藓(Plagiomnium acutum(Lindb.)Kop.)、侧枝匐灯藓(Plagiomnium maximoviczii(Lindb.)Kop.)、大凤尾藓(Fissidensnobilis Griff.)、大羽藓(Thuidium cymbifolium(Doz.et Molk.)B.S.G.)和大灰藓(Hypnum plumaeforme Wils.)嫩茎和老茎的石蜡切片和显微观察发现,同一藓类植株的嫩茎和老茎,茎结构稳定,不同种藓类植物茎横切面具有不同特征.植物体茎横切面形状、表层细胞的层数、细胞大小和细胞壁厚薄、皮层细胞大小和形状、中轴的有无以及比例等特征可以作为藓类植物的分科分类依据之一.     

真菌类遗传学分析的知识结构教学

本文以认知结构理论为指导,讨论了真菌类遗传分析与高等动植物遗传分析的内在联系,认为利用这种内在联系进行教学可收到好的效果并说明了作者的具体教学过程。 Abstract:In the paper, the relationship between genetic analysis of Fungi and genetic analysis of high animal and plant was discussed.A good results were obtained when we adopted this method in the teaching.     

Interconnection of parameters of regulation system of lipid peroxidation and of morphophysiological parameters of mouse liver

A complex analysis of seasonal fluctuations of the mean group parameters of the system of regulation of lipid peroxidation has been performed in liver of Balb/c mice. Association of lipid characteristics and morphophysiological parameters is studied in the Balb/c mouse liver. An inter-connection is revealed between the liver index and the amount of lysoforms of phospholipids, the scale and character of the interconnection differing essentially depending on proportion of phos-phatidylcholine in mouse liver phospholipids.     

History of the discovery of the mode of transmission of yellow fever virus

This essay documents and examines the historical circumstances and events surrounding the discovery of the mode of transmission of yellow fever virus in Cuba. Close scrutiny of the articles published by Walter Reed and his colleagues in 1900, 1901 and 1902 reveals their limitations as historic documents. Fortunately, other sources of information from that period survive in letters and documents written by individuals involved in the quest for the mode of transmission. Examination and comparison of those sources of information unveiled a fascinating story which reveals that misunderstandings engendered by published articles accorded merit where it was not fully due.     

Physiological characteristics of various species of strains of carboxydobacteria

Seven strains of aerobic carbon monoxide-oxidizing bacteria (carboxydebacteria) when growing on CO as sole source of carbon and energy had doubling times which ranged from 12–42 h. The activity profiles obtained after discontinuous sucrose density gradient centrifugation indicated that the CO-oxidizing enzymes are soluble and the hydrogenases are membrane-bound in all strains examined. The CO-oxidizing enzymes of Pseudomonas carboxydohydrogena, Pseudomonas carboxydoflava, Comamonas compransoris, and the so far unidentified strains OM2, OM3, and OM4 had a molecular weight of 230,000; that of Achromobacter carboxydus amounted to 170,000. The molecular weights of the CO-oxidizing and H₂-oxidizing enzymes turned out to be identical. The cell sonicates were shown to catalyze the oxidation of both CO and H₂ with methylene blue, thionine, phenazine methosulfate, toluylene blue, dichlorophenolindophenol, cytochrome c or ferricyanide as electron acceptors. Methyl viologen, benzyl viologen, FAD⁺, FMN⁺, and NAD(P)⁺ were not reduced. The spectrum of electron acceptors was identical for all strains tested. Neither free formate, hydrogen nor oxygen gas were involved in the CO-oxidation reaction. Methylene blue was reduced by CO at a 1:1 molar ratio. The results indicate that CO-oxidation by carboxydobacteria is catalyzed by identical or similar enzymes and that the reaction obeys the equation CO+H₂OCO₂+2H⁺+2e^- as previously shown for Pseudomonas carboxydovorans.Dedicated to Otto Kandler remembering almost three decades of enjoyable cooperation     

Modulation of allostery of pyruvate kinase by shifting of an ensemble of microstates

Since the introduction of the concepts of allostery about four decades ago, much advancement has been made in elucidating the structure-function correlation in allostery. However, there are still a number of issues that remain unresolved. In this review we used mammalian pyruvate kinase (PK) as a model system to understand the role of protein dynamics in modulating cooperativity. PK has a triosephosphate isomerase (TIM)(α/β)₈ barrel structural motif. PK is an ideal system to address basic questions regarding regulatory mechanisms about this common (α/β)₈ structural motif. The simplest model accounting for all of the solution thermodynamic and kinetic data on ligand-enzyme interactions involves two conformational states, inactive E^T and active E^R. These conformational states are represented by domain movements. Further studies provide the first evidence for a differential effect of ligand binding on the dynamics of the structural elements, not major secondary structural changes. These data are consistent with our model that allosteric regulation of PK is the consequence of perturbation of the distribution of an ensemble of states in which the inactive E^T and active E^R represent the two extreme end states. Sequence differences and ligands can modulate the distribution of states leading to alterations of functions. The future work includes: defining the network of functionally connected residues; elucidating the chemical principles governing the sequence differences which affect functions; and probing the nature of mutations on the stability of the secondary structural elements, which in turn modulate allostery.     

Time of detection of recessive genes: effects of system of mating and number of examined individuals

Summary Anthers were cultured from two sets of seven lines of hexaploid wheat (Triticum aestivum L.) with different cytoplasms, the euplasmic nucleus donors, Siete Cerros 66 and Penjamo 62, as well as their six alloplasmic lines derived from wild relative species of the genera Triticum and Aegilops. Significant cytoplasmic and nuclear effects but no cytoplasmic-nuclear interaction were found for embryogenic anther response, with the best performance of Penjamo 62 in Ae. kotschyi cytoplasm. Plant regeneration was not affected significantly by the cytoplasmic background of the lines cultured. The possible genetic implications of the observed cytoplasmic and nuclear influences on the in vitro haploid induction of wheat are discussed.