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1.
大连潮间带底栖海藻群落的数量特征和优势种的季节变化   总被引:5,自引:0,他引:5  
大连潮间带底栖海藻群落的数量特征和优势种的季节变化熊韶峻,王献平,郭旭光(辽宁师范大学生物系,大连116022)SeasonalVariationofQuantitativeCharactersandDominantSpeciesofBenthicSeaweedCommunitieswithinIntertidalsinDalian,China¥.XiongShaojun,WangXianping,GuoXuguang(DepartmentofBiolo-gy,LiaoningNormalUniuersity,Dalian116022).ChineseJournalofEcology,1993,12(4):27-29.Thecomposition,coverage,biornassanddorninantspeciesofbenthicseaweedcornmunltywithinintertidalinDalian,ChinaweremonthlyinvestigatedfrornMarch1990toMarch1991.Itisxhownthat1).thegen-eraltendencyofseaso  相似文献   

2.
安西荒漠植物群落和优势种的分布与环境的关系   总被引:6,自引:0,他引:6  
应用排序(DCA)和回归分析方法对安西砾石戈壁荒漠植物群落及优势种的分布与环境的关系进行了研究。结果表明,该区群落的盖度(C)和密度(D)均与年降水量(R)有密切关系,而群落的种类丰富度(N)则与土壤含盐量(S)相关,其回归关系式为:C=0.051968163e0.040786821R(R=0.95,P<0.01),D=0.27147913e0.052741829R(R=0.96,P<0.01),N=13.7748-6.477303lg1000S(R=0.83,P<0.01)。即:年降水量是决定戈壁荒漠植物群落盖度和密度的主要因素,土壤含盐量则与群落种类丰富度的关系尤为突出。优势种的抗旱性顺序是:红砂(Reaumuriasongorica((Pal.)Maxim.)>泡泡刺(NitrariasphaerocarpaMaxim.)>黑柴(SympegmaregeliBge.)>珍珠(SalsolapaserinaBge.)>膜果麻黄(EphedraprzewalskiStapf.),而耐盐性顺序是:珍珠>红砂>黑柴>泡泡刺>膜果麻黄  相似文献   

3.
英加  陈佩度 《遗传学报》2000,27(6):506-510
对普通小麦(Triticum aestivum)-节节麦(Aegilops squarrosa)八倍体(2n=8x=56,AABBDDDD)与硬粒小麦(Triticum durum)-簇毛麦9Haynaldia villosa)六倍体(2n=6x=42,AABBVV)杂交后,将所得七倍体杂种(AABBDDV)进行连续自交,在F4代中利用C-分带鉴定出可能的簇毛麦6V二体附加系95-7和2V二体附加  相似文献   

4.
动脉平滑肌细胞(SMC)的增殖在动脉粥样硬化(AS)的形成过程中极其重要。我们在建立人主动脉SMC体外培养方法的基础上,观察了LDL,VLDL及HDL和相应的氧化修饰型脂蛋白对培养人SMCsis,jun,H-ras原癌基因及Rb抗癌基因转录表达的影响。结果表明:(1)HDL对SMCsis,jun,ras基因表达无影响;(2)LDL和VLDL有使这些基因表达增加的趋势;(3)ox-LDL,ox-VLDL和ox-HDL具有使SMCsis,jun,和ras基因表达显著增强的作用(P<0.01),且其作用较相应的天然脂蛋白大(P<0.01);(4)天然和氧化修饰型脂蛋白对Rb基因表达均无影响。据上述结果推测:LDL,VLDL,ox-LDL,ox-VLDL和ox-HDL的致AS作用可能与刺激SMCsis,jun和ras原癌基因表达增加有关。  相似文献   

5.
鸡减蛋综合征病毒(EggDropSyndromeVirus,EDSV)巯基内肽酶的基因序列分析曾力宇1金奇1朱雷1章金钢2殷震2侯云德1关键词鸡减蛋综合征病毒(EDSV),巯基内肽酶(Thiol-endopeptidase),核苷酸序列分析EDS病毒...  相似文献   

6.
新城疫基因工程疫苗研究进展   总被引:3,自引:0,他引:3  
新城疫基因工程疫苗研究进展霍龙飞,王莉林,卢景良(哈尔滨兽医研究所备医生物技术国家重点实验室,哈尔滨)鸡新城疫(ND)是由新城疫病毒(New-castleDiseaseVirus,NDV)所致的一种死亡率很高急性败血性高度接触性禽类传染病,也是养禽业...  相似文献   

7.
KEYWORDINDES(1996,Vol.17)Abundance(3):232ACAserum(4):499,507Accipitridae(4)=482Adenohypophysis(l):78Aerialrespiration(2):151A...  相似文献   

8.
天然及氧化修饰脂蛋白对人动脉平滑肌细胞原癌基因…   总被引:9,自引:1,他引:8  
动脉平滑肌细胞(SMC)的增殖在动脉粥样硬化(AS)的形成过程中极其重要。我们在建立人主动脉SMC体外培养方法的基础上,观察了LDL,VLDL及HDL和相应的氧化修饰型脂蛋白对培养人SMC sis,jun,H-ras原癌基因及Rb抗癌基因转录表达的影响。结果表明:(1)HDL对SMCsis,jun,ras基因表达无影响;(2)LDL和VLDL有使这些基因表达增加的趋势;(3)ox-LDL,ox-V  相似文献   

9.
肿瘤微血管密度检测及其意义   总被引:1,自引:0,他引:1  
近年来,随着对肿瘤血管生长与抑制研究的深入,肿瘤微血管密度(Microvesseldensity,MVD)与预后的关系越来越受到人们的关注。为观察放射介入治疗大肠癌后,肿瘤MVD变化情况,用第八因子相关抗原(F8),以免疫组化技术,SP法,对60例大...  相似文献   

10.
闫庆国  朱德生 《病毒学报》2000,16(4):327-331
为明确何杰金病(Hodgkin’s disease,HD)瘤细胞中是否存在人巨细胞病毒(human cytomegalovirus,HCMV)感染,采用显微切割技术结合PCR方法检测HD组织及其瘤细胞Hodgkin/Reed-Sternberg(H/RS)中的HCMV核酸;采用免疫组织化学催化信号扩增(catalysed signal amplification,CSA)法检测HD中HCMV的立即  相似文献   

11.
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.  相似文献   

12.
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 Pfr.  相似文献   

13.
14.
真菌类遗传学分析的知识结构教学   总被引:5,自引:2,他引:3  
罗桂花 《遗传》2002,24(3):349-350
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.  相似文献   

15.
The levels of endogenous phytohormones and respiratory rate in nine sorts of flowers such as Cymbidium faberi Rolfe, Nopalxochia ackermannii Kunth and others were investigated both at full bloom and senescence and meanwhile the effect of exogenous phytohormones on prolonging the blossoms and promoting ethylene production were tested. There is a high content of endogenous ethylene in all the long-lived flowere, about 3–16 folds higer than the short-lived ones. There is a high level of ABA at full blooming flowers of short-lived flowers, in which there is no or only some cytokinins in it, but the ratio of CTK (6BA+zeatin)/ABA is smaller(l.7). The endogenous ABA reached a much higher level at senescence in all nine sorts of flowers, so it is reasonable to consider that it is ABA which plays an important role of regulation in controlling flower's senescence. There is a much higher level of GA3 and zeatin in the long-lived flowers which is not demonstrated in the shortlived ones. The respiratory rate is one of the factors controtling the longevity of flowers, but it does not play a decided role. Application of 6BA and zeatin prolongs distinctly orchid’s longevity, however exogenous IAA through the promotive action on ethylene production, evidently extends the longevity of the flowers of the Nopalxochia ackermannii Kunth.  相似文献   

16.
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.  相似文献   

17.
龙胆科药用植物化学成分的研究现状   总被引:16,自引:0,他引:16  
龙胆科植物在我国的分布范围很广,且多数为药用植物,其多数种属的药用植物,至今其化学成分尚未被系统研究。综述了目前龙胆科药用植物的化学成分的研究现状及一般提取方法,对近年来发现的环烯醚萜及裂环烯醚萜类化合物进行了总结,为本科药用植物的更深入研究提供了参考。  相似文献   

18.
19.
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  相似文献   

20.
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 ET and active ER. 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 ET and active ER 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.  相似文献   

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