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1.
云南纵坑切梢小蠹四个地理种群同工酶比较研究   总被引:7,自引:0,他引:7  
邹平  叶辉  谭德勇  昝瑞光 《遗传》1999,21(6):27-31
采用不连续聚丙烯酰胺凝胶电泳技术研究了纵坑切梢小蠹(Tom icus piniperda L.)4 个自然种群的9 个同工酶基因座。4 个种群均在Es- 1、Es- 2、Es- 4、Mdh- 1、Mdh- 2 及AAT- 1 基因座上存在遗传多态现象。路南长湖、楚雄、蒙自3 种群间的遗传距离为0.0036~0.0173, 平均值为0.0105, 表明其遗传结构基本相似。丽江种群与上述3 种群之间的遗传距离为0.1421~0.2035, 平均值为0.1765,表明丽江种群与上述三种群已有了遗传分化。丽江种群近交系数较大,近亲繁殖程度较高。种群遗传结构的差异可能与不同蠹害程度之间存在一定的内在联系。  相似文献   

2.
对欧洲及地中海地区燕麦草复合体27个居群的等位酸电泳调查表明,燕麦草复合体维持比较高的等位酶多样性(He=0.447,A=3.29),亚种间遗传分化较小(G(ST)=0.053);在四个亚种内,也维持着比较高的多样性(He:0.325—0.533),各亚种内的基因多样度主要存在于居群之内,居群间分化较小.四倍体的基因多样性高于二倍体的.燕麦草复合体内居群间基因流较高,表明燕麦草繁育方式主要为风媒远交.对Nei氏标准遗传距离的UPGMA聚类结果表明,四倍体是从二倍体有鳞茎的ssP.baeticum中产生的.  相似文献   

3.
小鲤Cyprinus micristius分布于云南省的滇池、抚仙湖和星云湖,对历年馆藏和作者近年定期野外收集的200尾标本和生态资料进行综合分析的结果表明:小鲤已分化为两个地理亚种,即滇池特有的小鲤指名亚种C.(M.)micristius micristius Regan和分布于抚仙湖、星云湖的抚仙小鲤C.(M.)micristius fuxianensis Yang et al.,亚种间形态的  相似文献   

4.
分析了苍术(Atractylodeslandea(Thunb.)DC.)5种等位酶(MDH,GDH,PPO,SOD,PER)12个位点上25个等位基因的分化特征。结果表明:群体内多态位点比例平均为0.61,每个位点的平均杂合率为0.26,每个位点发现的平均等位基因数为1.78。苍术种内基因多样性的86%产生在群体内,群体间分化的明显效果为14%。所有配对组合,群体间的平均遗传距离是0.11,遗传同一性是0.90。说明苍术种内变异很大。同时探讨茅苍术的分类位置,认为茅苍术不是苍术和白术的杂交种。  相似文献   

5.
恽锐  王洪新 《Acta Botanica Sinica》1998,40(11):1040-1046
通过植物群落结构、壳斗、叶脉形态特征、同工酶及DNA等多方面调查与测定,分析了帽儿山的蒙古栎(QuercusmongolicaFisch.)和东灵山、关帝山的辽东栎(Q.liaotungensisKoidz.)的遗传分化及多样性。各种水平的研究一致说明:两种植物的遗传分化较小,东灵山种群是典型蒙古栎、辽东栎种群的中间类型。确切地说,从东北到山西组成一个地理渐变群,存在大范围、强大的双向基因流  相似文献   

6.
宿兵  王文 《遗传学报》1997,24(2):109-115
采用蛋白电泳分析技术研究了来源于我国和越南的猕猴属(Gen usMacaca)5个种(M.mulatta、M.arctoides、M.assamensis、M.thibetana、M.fascicularis)的蛋白多态性及其遗传分化关系。共分传座位30个。在分析的19只恒河猴中,30个遗传座有位9个座位表现出多态性,多态座位百分比P=0.3,平均等位基因数A=1.4,平均杂合度H=0.01045  相似文献   

7.
中国貉随机扩增多态DNA及其亚种分化关系   总被引:29,自引:2,他引:27  
对来自陕西、云南、越南、安徽和广西等地的8只中国貉(Nyctereutesprocyonides)进行随机扩增多态DNA分析。应用28个10bp的随机引物,平均每只貉获得的RAPD标记数约为130条。遗传距离计算结果显示,中国貉个体间的平均遗传距离指数值为11.20%,最大值为14.93%,最小值为2.94%。以赤狐(Vulpesvulpes)为外群,应用PHYLIP3.0计算软件包中的UPGMA和NJ聚类方法构建分子系统树。结果表明,不同地理群体间的中国貉存在遗传分化;中国貉可分为4组:(1)广西貉,(2)安徽貉,(3)陕西貉,(4)云南貉和越南貉。其中安徽貉和广西貉间的关系稍近,陕西貉则与云南貉-越南貉稍近。对合中国貉的形态分类、地理分布、mtDNA多态分析以及进化遗传学的观点,认为陕西貉、广西貉和安徽貉可能与云南貉-越南貉具有等同的分类地位。  相似文献   

8.
四种松毛虫不同地理种群遗传多样性的等位酶分析   总被引:3,自引:0,他引:3  
【目的】采用等位酶电泳技术对中国松毛虫属Dendrolimus 4种共9个地理种群进行遗传多样性和遗传分化研究。【方法】对6种等位酶系统乳酸脱氢酶(LDH)、苹果酸脱氢酶(MDH)、苹果酸酶(ME)、乙醇脱氢酶(ADH)、甲酸脱氢酶(FDH)、谷氨酸脱氢酶(GDH)进行聚丙烯酰胺凝胶电泳分析。【结果】在4种松毛虫9个地理居群中共检测到10个基因位点,其中4个位点为多态位点,检测到17个等位基因; 种群总体水平多态位点比率P=40%,平均有效基因数A=1.700,平均期望杂合度He=0.151,种群平均遗传距离为0.001~0.285; 其中马尾松毛虫指名亚种Dendrolimu punctatus Walker 6个居群的遗传分化度Fst=0.265,基因流Nm=0.692。4种松毛虫之间遗传关系最近的是落叶松毛虫D. superans Butler和马尾松毛虫的地理亚种赤松毛虫D. punctatus spectabilis Butler,遗传关系最远的是落叶松毛虫D. superans Butler和云南松毛虫D. houi Lajonquiere。【结论】 马尾松毛虫居群间遗传分化程度较大,基因交流较少,遗传漂变已经成为导致该物种种群分化的主要原因之一;遗传距离与地理距离存在一定相关性。  相似文献   

9.
中国牦牛线粒体DNA多态性及遗传分化   总被引:27,自引:3,他引:24  
涂正超  邱怀 《遗传学报》1998,25(3):205-212
用20种限制性内切酶分析了我国5个牦牛群体90个个体的限制性片段长度多态性,其中AvaI,AvaII、BglII、EcoRI.HindIII、HpaI6个酶切类型具有多态性,共发现5种mtDNA单倍型,每种单倍型中检出50-55个位点,并利用双酶切制定出其物理图谱。我国牦牛群体mtDNA多样度HT为0.1065,群体内的平均一致性概率为0.8966,表明我国牦牛群体mtDNA多态性较贫乏,群体间的平均净遗传距离Pet为0.000201,群体基因分化系数Gst为0.0291,我国牦牛群体mtDNA变异只有2.91%来自群体间的差异,群体间的分化程度较低。并根据报道,比较了牦牛和其他家养牛种的mtDNA遗传分化,估计出牦牛和普通牛、瘤牛的分化时间大约分别在1.1-2.2百万年和1.01-1.02百万年之间。  相似文献   

10.
栗属中国特有种居群的遗传多样性及地域差异   总被引:38,自引:0,他引:38  
采用超薄平板聚丙烯酰胺等电聚焦技术对栗属(Castanea(Tourn.)L.)3个中国特有种即中国板栗(C.molisimaBL.)、茅栗(C.seguiniDode.)和锥栗(C.henryi(Skan)Rehd.etWils.)的30个居群,12个酶系统的20个位点进行了遗传多样性与遗传结构分析。结果表明:中国板栗在种和居群水平都具有较茅栗、锥栗高的遗传多样性(P分别为90.0%和84.7%,He分别为0.311和0.295),尤以长江流域居群表现显著,揭示了长江流域的神农架及周边地区为中国板栗的遗传多样性中心。Nei的遗传一致度测量结果显示中国板栗和茅栗的亲缘关系最近,并且地理距离和遗传距离有一定的相关性。中国板栗、茅栗和锥栗的遗传分化程度逐渐增大,Gst分别为7.5%、10.9%和22.1%;基因流(Nm)分别为3.20、2.05和0.88。研究结果为探明栗属起源、系统进化及制定保育策略提供了科学依据。  相似文献   

11.
Defects in mitochondrial energy metabolism have been implicated in the pathology of several neurodegenerative disorders. In addition, the reactive metabolites generated from the metabolism and oxidation of the neurotransmitter dopamine (DA) are thought to contribute to the damage to neurons of the basal ganglia. We have previously demonstrated that infusions of the metabolic inhibitor malonate into the striata of mice or rats produce degeneration of DA nerve terminals. In the present studies, we demonstrate that an intrastriatal infusion of malonate induces a substantial increase in DA efflux in awake, behaving mice as measured by in vivo microdialysis. Furthermore, pretreatment of mice with tetrabenazine (TBZ) or the TBZ analogue Ro 4-1284 (Ro-4), compounds that reversibly inhibit the vesicular storage of DA, attenuates the malonate-induced DA efflux as well as the damage to DA nerve terminals. Consistent with these findings, the damage to both DA and GABA neurons in mesencephalic cultures by malonate exposure was attenuated by pretreatment with TBZ or Ro-4. Treatment with these compounds did not affect the formation of free radicals or the inhibition of oxidative phosphorylation resulting from malonate exposure alone. Our data suggest that DA plays an important role in the neurotoxicity produced by malonate. These findings provide direct evidence that inhibition of succinate dehydrogenase causes an increase in extracellular DA levels and indicate that bioenergetic defects may contribute to the pathogenesis of chronic neurodegenerative diseases through a mechanism involving DA.  相似文献   

12.
葫芦科植物包括多种瓜类蔬菜,对其进行离体培养研究具有重要的理论和实践意义。综述了国内在葫芦科植物器官培养、体细胞胚胎发生、花药培养、原生质体培养和体细胞杂交及离体遗传转化等方面取得的研究进展,并对葫芦科植物离体培养、遗传转化与育种的前景作了展望。  相似文献   

13.
Somatostatin (SST) peptide is a potent inhibitor of insulin secretion and its effect is mediated via somatostatin receptor 5 (SSTR5) in the endocrine pancreas. To investigate the consequences of gene ablation of SSTR5 in the mouse pancreas, we have generated a mouse model in which the SSTR5 gene was specifically knocked down in the pancreatic beta cells (betaSSTR5Kd) using the Cre-lox system. Immunohistochemistry analysis showed that SSTR5 gene expression was absent in beta cells at three months of age. At the time of gene ablation, betaSSTR5Kd mice demonstrated glucose intolerance with lack of insulin response and significantly reduced serum insulin levels. Insulin tolerance test demonstrated a significant increase of insulin clearance in vivo at the same age. In vitro studies demonstrated an absence of response to SST-28 stimulation in the betaSSTR5Kd mouse islet, which was associated with a significantly reduced SST expression level in betaSSTR5Kd mice pancreata. In addition, betaSSTR5Kd mice had significantly reduced serum glucose levels and increased serum insulin levels at 12 months of age. Glucose tolerance test at an older age also indicated a persistently higher insulin level in betaSSTR5Kd mice. Further studies of betaSSTR5Kd mice had revealed elevated serum C-peptide levels at both 3 and 12 months of age, suggesting that these mice are capable of producing and releasing insulin to the periphery. These results support the hypothesis that SSTR5 plays a pivotal role in the regulation of insulin secretion in the mouse pancreas.  相似文献   

14.
2018年中国植物科学若干领域重要研究进展   总被引:1,自引:0,他引:1  
2018年中国植物科学继续呈现快速发展的态势, 我国科学家在国际植物科学主流学术刊物发表论文数量大幅增加, 取得了多项具有重要影响的成果。调控植物生长-代谢平衡实现可持续农业发展入选2018年度中国科学十大进展; 中国被子植物区系进化历史研究入选2018年度中国生命科学十大进展。以水稻为代表的农作物和果蔬等经济作物研究在国际上已呈现出明显的优势, 若干领域已从“追赶”状态跨越到“领跑”地位。该文对2018年中国科学家在植物科学若干领域取得的重要研究成果进行了概括性评述, 旨在全面追踪和报道当前中国植物科学领域的发展前沿和热点, 展示中国科学家所取得的杰出成就。  相似文献   

15.
2018年中国植物科学继续呈现快速发展的态势, 我国科学家在国际植物科学主流学术刊物发表论文数量大幅增加, 取得了多项具有重要影响的成果。调控植物生长-代谢平衡实现可持续农业发展入选2018年度中国科学十大进展; 中国被子植物区系进化历史研究入选2018年度中国生命科学十大进展。以水稻为代表的农作物和果蔬等经济作物研究在国际上已呈现出明显的优势, 若干领域已从“追赶”状态跨越到“领跑”地位。该文对2018年中国科学家在植物科学若干领域取得的重要研究成果进行了概括性评述, 旨在全面追踪和报道当前中国植物科学领域的发展前沿和热点, 展示中国科学家所取得的杰出成就。  相似文献   

16.
2017年中国植物科学若干领域重要研究进展   总被引:1,自引:0,他引:1  
2017年中国植物科学继续保持高速发展态势, 重大成果频出, 具体表现在中国植物学家在国际顶级学术期刊发表的文章数量平稳上升。中国植物科学领域的研究工作者成果精彩纷呈, 如新型广谱抗病机制的发现、水稻广谱抗病遗传基础及机制和疫霉菌诱发病害成灾机制研究等。2017年中国生命科学领域十大进展评选中, 有两项植物科学领域的研究成果入选。水稻生物学、进化与基因组学和激素生物学等领域学科发展突出。另外, 值得一提的是, 长期从事高等植物与代谢途径调控分子网络研究和水稻品种设计育种的李家洋院士的研究成果“水稻高产优质性状形成的分子机理及品种设计”荣获2017年国家自然科学一等奖。这一具有重大国际影响的开创性贡献标志着中国植物科学在该领域的国际科学前沿居于引领和卓越地位。该文对2017年中国本土科学家在植物科学若干领域取得的重要研究成果进行了系统梳理, 旨在全面追踪和报道当前中国植物科学领域发展的最新前沿动态, 与广大读者共同分享我国科学家所取得的辉煌成就。  相似文献   

17.
我国葫芦科植物离体培养研究进展   总被引:5,自引:0,他引:5  
葫芦科植物包括多种瓜类蔬菜,对其进行离体培养研究具有重要的理论和实践意义.综述了国内在葫芦科植物器官培养、体细胞胚胎发生、花药培养、原生质体培养和体细胞杂交及离体遗传转化等方面取得的研究进展,并对葫芦科植物离体培养、遗传转化与育种的前景作了展望.  相似文献   

18.
Abstract. Changes are described in aquatic vegetation in oligotrophic, groundwater-fed Rhine floodplain streams in Alsace (eastern France), resulting from disturbance. Disturbance factors include changes in nutrients, either permanent ones - effluent from a waste water treatment plant or trout hatcheries - or periodic ones: flooding. Regular inputs of high levels of phosphate and ammonia modified the macrophyte vegetation in these streams. The floristic composition, which was characteristic of oligotrophic waters upstream of the eutrophicated sector, changed to that of a eutrophic situation as originally found downstream. Periodic disturbance by floods which normally occur once a year, irregularly eutrophicates the small streams, causing the development of a mixture of eutrophic and oligotrophic species. Six macrophyte communities are distinguished, indicating different trophic levels. The aquatic vegetation is adapted to the variations of phosphate and ammonia levels. Hence, aquatic macrophytes can be used as bio-indicators of fluctuations in water nutrient levels in relation to the type of disturbance.  相似文献   

19.
The detailed mechanisms underlying morphine-signaling pathways in platelets remain obscure. Therefore, we systematically examined the influence of morphine on washed human platelets. In this study, washed human platelet suspensions were used for in vitro studies. Furthermore, platelet thrombus formation induced by irradiation of mesenteric venules with filtered light in mice pretreated with fluorescein sodium was used for an in vivo thrombotic study. Morphine concentration dependently (0.6, 1, and 5 microM) potentiated platelet aggregation and the ATP release reaction stimulated by agonists (i.e., collagen and U46619) in washed human platelets. Yohimbine (0.1 microM), a specific alpha(2)-adrenoceptor antagonist, markedly abolished the potentiation of morphine in platelet aggregation stimulated by agonists. Morphine also potentiated phosphoinositide breakdown and intracellular Ca(2+) mobilization in human platelets stimulated by collagen (1 microg/ml). Moreover, morphine (0.6-5 microM) markedly inhibited prostaglandin E(1) (10 microM)-induced cyclic AMP formation in human platelets, while yohimbine (0.1 microM) significantly reversed the inhibition of cyclic AMP by morphine (0.6 and 1 microM) in this study. The thrombin-evoked increase in pH(i) was markedly potentiated in the presence of morphine (1 and 5 microM). Morphine (2 and 5 mg/g) significantly shortened the time require to induce platelet plug formation in mesenteric venules. We concluded that morphine may exert its potentiation in platelet aggregation by binding to alpha(2)-adrenoceptors in human platelets, with a resulting inhibition of adenylate cyclase, thereby reducing intracellular cyclic AMP formation followed by increased activation of phospholipase C and the Na(+)/H(+) exchanger. This leads to increased intracellular Ca(2+) mobilization, and finally potentiation of platelet aggregation and of the ATP release reaction.  相似文献   

20.
We report the appearance of apoptotic cells in experimental myocardial infarction (rabbit heart) in in situ and in vitro preparations. Apoptosis was recognized by intravital staining with Hoechst 33342 (Ho342), by nick-end labeling (TUNEL) and by DNA laddering. A steady rise in the relative number of apoptotic cardiomyocytes (apoptotic index) was noted in in situ preparations. Apoptosis was first noted 6 h after the onset of ischemia with its highest value occurring after 72 h. Apoptotic nuclei were absent in remote areas of the left and right ventricles. Apoptotic nuclei within the infarcted area showed diminished intensity of Ho342 fluorescence. Three days after ischemia, a border zone adjacent to the infarcted area consisting of apoptotic macrophages was recognized. A novel finding was the appearance of apoptotic cardiomyocytes in the isolated perfused ischemic heart. Occurring as early as 50 min after the onset of ischemia, a high apoptotic index was present adjacent to the ligature placed around the coronary artery. This observation provides the opportunity to selectively examine factors leading to apoptosis in the ischemic heart under controlled experimental conditions.  相似文献   

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