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报道了广义报春苣苔属14种3变种和7个未定名种的染色体数目,并对其近缘属——广义石山苣苔属的3个种也进行了细胞学研究。结合最近的分类处理和系统发育假设,对所得结果和以前发表的染色体数据进行了综合分析, 结果表明:广义报春苣苔属的染色体数目为2n=36,基数为x=18,表现出高度稳定性。染色体相对较小,以中间着丝粒和亚中间着丝粒染色体为主。尽管一些类群的染色体大小之间存在微小差异,但是染色体形态的均一性和染色体数目的一致性有力地支持分子系统学的研究结果。另外,相同的染色体数目及相似的染色体形态也表明广义报春苣苔属和广义石山苣苔属的亲缘关系较近,与分子系统学的结果一致。 相似文献
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广义报春苣苔属(苦苣苔科)的染色体新计数及其分类学意义 总被引:1,自引:0,他引:1
报道了广义报春苣苔属14种3变种和7个未定名种的染色体数目,并对其近缘属-广义石山苣苔属的3个种也进行了细胞学研究。结合最近的分类处理和系统发育假设,对所得结果和以前发表的染色体数据进行了综合分析,结果表明:广义报春苣苔属的染色体数目为2n=36,基数为x=18,表现出高度稳定性。染色体相对较小,以中间着丝粒和亚中间着丝粒染色体为主。尽管一些类群的染色体大小之间存在微小差异,但是染色体形态的均一性和染色体数目的一致性有力地支持分子系统学的研究结果。另外.相同的染色体数目及相似的染色体形态也表明广义报春苣苔属和广义石山苣苔属的亲缘关系较近,与分子系统学的结果一致。 相似文献
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对报春花科(Primulaceae)报春花属(Primula)灯台报春组植物Section Proliferoe的7种报春进行了细胞学研究,其中腾冲灯台报春和川东灯台报春的核型分析为首次报道,结合已报道的灯台报春组其它植物的细胞学资料进行统计分析,结果表明灯台报春组植物在染色体基数、染色体形态、着丝点位置及染色体对称性上都具有很高的一致性,在灯台报春组有核型记录的种类中,其核型都属于Stebbins的2A型或2B型,核型差异很小,染色体基数均为x=11,推测其可能与报春花属中具有相同染色体基数的组亲缘关系更近。结合已发表的灯台报春组植物的细胞学资料及它们的形态特征,对其系统演化关系进行了比较分析,以期对该组的系统学及演化关系提供一些证据。 相似文献
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本文报道了四川峨眉山、云南点苍山和北京雾灵山产的25种蕨类植物的染色体数目,其中15种的染色体数目和4个种的细胞型是首次记载。此外,还对荚囊蕨属(Struthiote-ris)和水龙骨属(Ppolypodiodes)等属的染色体基数进行了讨论。 相似文献
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石山苣苔属(苦苣苔科)约41种,主要分布于我国西南石灰岩地区。到目前为止,仅其中四种的染色体数目被研究和报道,其余绝大多数物种的染色体数目和倍性尚不清楚,染色体数目和倍性在该属及其姐妹属报春苣苔属中的演变历史及其对两属物种多样性分化的影响亦不清楚。该文以叶片水培生根法获取的四种(含一变种)石山苣苔属植物 [即石山苣苔原变种(Petrocodon dealbatus var. dealbatus)、齿缘石山苣苔(Petrocodon dealbatus var. denticulatus)、弄岗石山苣苔(Petrocodon longangensis)、石山苣苔未定名种(Petrocodon sp.)]的根尖细胞为材料开展染色体实验,探索了多种不同的实验条件对染色体制片效果的影响并获取染色体数目,在石山苣苔属和报春苣苔属的系统树上追踪了染色体数目和倍性的演变历史,同时探讨染色体数目尤其是倍性变化是否对两属物种多样性分化存在影响。结果表明:(1)长度为1~1.5 cm的根尖,0.002 mol·L-1 8-羟基喹啉溶液预处理5 h,解离4 min为较适宜的染色体制备条件。(2)四种(含一变种)石山苣苔属植物染色体数目一致,均为二倍体(2n=2x=36)。(3)两属之间及两属各自的最近共同祖先染色体数目尚不能确定,除个别物种染色体条数或倍性有变化以外,其余已知染色体数目的物种均为2n=2x=36,在两属中高度一致,石山苣苔属与报春苣苔属物种多样性分化尤其两属物种多样性巨大差异与染色体数目和基因组倍性变化无关。综上结果为石山苣苔属植物及其近缘类群染色体制备提供了参考,也为进一步对该类群的分类、系统演化和物种形成等方面的研究提供了基础数据和启示。 相似文献
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新疆多年生小麦族植物染色体数的观察 总被引:6,自引:0,他引:6
本文对1987年采集于新疆的多年生小麦族(Triticeae Dum. )属种进行了细胞学观察。该地区多年生小麦族各属种的染色体数目变化范围是从2n=14到2n=84,前者主要存在于大麦属(Hordeum)、新麦草属(Psathyrostachys),而后者全部集中于赖草属(Leymus).其中染色体数目为2n=28和2n=42的频率最高,主要存在于鹅冠草属(Roegneria)和披碱草属(Elymus)。Roegneria gobicola, Roegneria kuqaensis, Roegneria tahelacona, Roegneria zhoasuensis的染色体数为首次报道。 相似文献
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独尾草属(Eremurus M. Bieb)全世界约有20多种,主要分布于中亚及西亚的山地和平原沙漠地区。我国产4种,其中独尾草(E. chinensis Fedtsch. )主要分布于四川、云南和西藏,在甘肃南部的岷县、舟曲、武都、文县也有分布。其染色体数目和核型迄今未见报道,本文对采 相似文献
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九种报春花属植物的核形态学研究 总被引:12,自引:3,他引:9
对报春花属(Prinula)4个组9种植物进行了核形态学研究。这9个种的间期核构形均为复杂染色中心型,前期染色体属于中间型,体细胞有丝分裂中期染色体的数目及核型如下:中甸海水仙报表P.monticola(Hand.-Mazz.)Chen et C.M.Hu,K(2n)=16=12m 4sm;高穗花报春P.vialii Delavay ex Franch.,K(2n)=20=16m 2sm 2st;偏花报春P.secundiflora Franch.,K(2n)=22=18m 4sm;海仙花报春P.poissonii Fanch.,K(2n)=22=16m 6sm;霞红灯台报春P.beesiana Forr.,K(2n)=22=18m 4sm;桔红灯台报春P.bulleyana Forr., K(2n)=22=18m 4sm;橙红灯台报春P.aurantiaca W.W.Smith et Forr.,K(2n)=22=16m(sat) 6sm;粉被灯台报春P.pulverulenta Duthie,K(2n)=22=19m 2sm 1st;钟花报春P.sikkimensis Hook.,K(2n)=20=14m(1sat) 4sm 2T。其中,中甸海水仙报春和高穗花报春两种的染色体数目及核型为首次报道。同时,本文还将偏花报春与灯台组报春以及钟花组报春进行了细胞学的比较分析。 相似文献
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Chromosome numbers and karyotypes of 13 populations of six Oxytropis species (Fabaceae) from the Qinghai Tibetan Plateau, China, were presented. The chromosome numbers and karyotypes in O.ochrocephala, O.tatarica, O.kansuensis and O.humifusa (2n=16) were reported for the first time. B chromosomes were found from O.stracheyana (2n=48). The basic chromosome number of x=8 is confirmed for the genus. The available chromosomal data indicate that polyploidy may have played an important role in the evolution of the genus, with the incidence of polyploidy in the genus reaching 58%. However, our results indicated that among the populations here examined only one was a hexaploid with 2n=48. Such a chromosomal pattern indicates that the karyotypic repatterning at the diploid level seems to be the predominant feature of chromosomal evolution in the Oxytropis species from the Qinghai Tibetan Plateau, and that sympatric speciation via hybridization and polyploidization has played a minor role in the species diversification of the genus from this area. 相似文献
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Schwanke U Heusch G Schipke JD 《Physiological research / Academia Scientiarum Bohemoslovaca》2002,51(1):17-25
Myocardial blood flow is spatially heterogeneous, reflecting nonuniform oxygen supply. Also, myocardial oxidative metabolism is spatially heterogeneous. The effects of acute ischemia and reperfusion on the relationship between local myocardial blood flow (LMF) and oxidative metabolism are still unknown. LMF was measured in isolated, blood-perfused rabbit hearts using colored microspheres and oxidation water labeled with 18O2 (H2(18)O). Three protocols were performed: 18O2-perfusion during normoxia (N; n=7), during early reperfusion (ER; 10 min, n=6), and late reperfusion (LR; 40 min, n=6) following 20 min no-flow ischemia. LMF and local H2(18)O residues were determined within defined myocardial samples (105+/-15 mg). For interindividual comparison, values were normalized to the mean of the individual experiment and expressed as percentages. LMF ranged from 18 to 193% (N), 12 to 250% (ER), and 11 to 180% (LR). The H2(18)O tissue residue ranged from 63 to 132% (N), 73 to 142% (ER) and 32 to 148% (LR). The correlation between LMF and local oxidative metabolism during N (r=0.77; n=56) was lost in the postischemic heart during ER and LR. LMF during N and ER were only weakly correlated (r=0.24; n=48), whereas LMF during N and LR correlated well (r=0.87; n=48). It is concluded that the heterogeneous LMF pattern at baseline is maintained in the stunned myocardium whereas that of local oxidative metabolism is not. Apart from the established mechanisms underlying myocardial stunning, a mismatch between local flow and oxidative metabolism might also contribute. 相似文献
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对6种棘豆属植物(Oxytropis)的13个居群样进行细胞学研究,其中黄花棘豆(O.ochrocephala)、绢毛棘豆(O.tatarica)、甘肃棘豆(O.kansuensis)和铺地棘豆(0.humifusa)为首次报道染色体数目(2n=16)和核型;在胀果棘豆(O.stracheyana)中(2n=48)首次发现B染色体。现有的细胞学资料表明:棘豆属植物中多倍体占总报道数的58%,这说明多倍化在本属植物的进化过程中起着非常重要的作用,但青藏高原仅有一种植物发现多倍体,多倍化并不占主导地位,而主要表现为二倍体水平上的结构变异,即核型不对称性的变化。 相似文献
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Characterization of Vibrio anguillarum and closely related species isolated from farmed fish in Norway. 总被引:11,自引:0,他引:11
E Myhr J L Larsen A Lillehaug R Gudding M Heum T H?stein 《Applied and environmental microbiology》1991,57(9):2750-2757
A total of 264 bacterial strains tentatively or definitely classified as Vibrio anguillarum were examined. The strains were isolated from diseased or healthy Norwegian fish after routine autopsy. With the exception of five isolates from wild saithe (Pollachius virens), the strains originated from nine different species of farmed fish. The bacteria were subjected to morphological, physiological, and biochemical studies, numerical taxonomical analyses, serotyping by slide agglutination and enzyme-linked immunosorbent assay, DNA-plasmid profiling, and in vitro antimicrobial drug susceptibility testing. The results of the microbiological studies were correlated to anamnestic information. The bacterial strains were identified as V. anguillarum serovar O1 (n = 132), serovar O2 (n = 89), serovar O4 (n = 2), serovar O8 (n = 1), and not typeable (n = 1) as well as Vibrio splendidus biovar I (n = 36) and biovar II (n = 1), Vibrio tubiashii (n = 1), and Vibrio fischerii (n = 1). V. anguillarum serovar O1 or O2 was isolated in 176 out of 179 cases of clinical vibriosis in Atlantic salmon (Salmo salar). V. anguillarum serovar O1 was the only serovar isolated from salmonid fish species other than Atlantic salmon, while V. anguillarum serovar O2 was isolated from all marine fish suffering from vibriosis. A 48-Mda plasmid was isolated from all V. anguillarum serovar O1 isolates examined. Serovar O2 isolates did not harbor any plasmids. Resistance against commonly used antibiotic compounds was not demonstrated among V. anguillarum isolates. Neither V. splendidus biovar I nor other V. anguillarum-related species appeared to be of clinical importance among salmonid fish.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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鲱形目和鲈形目七种鱼的核型分析 总被引:18,自引:0,他引:18
本文利用体内注射秋水仙素、低渗和空气干燥法,分析了7种海产鱼的染色体组型;鲱形目的斑和青鳞小沙丁,鲈形目的花鲈、皮氏叫姑鱼、黄姑鱼、小黄鱼和黄鳍刺假虎鱼。并结合前人的文献,讨论了鲱形目的核型演化,将鲈形目几种鱼的核型与前人的报道作了比较。 相似文献
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NADH fluorescence of isolated ventricular myocytes: effects of pacing, myoglobin, and oxygen supply. 总被引:7,自引:1,他引:6 下载免费PDF全文
Endogenous fluorescence was used to measure the extent of reduction of mitochondrial NAD in individual, isolated rat cardiac myocytes. NAD reduction was determined from emitted fluorescence at 415 and 470 nm during brief epi-illumination at 365 nm. NAD reduction of resting myocytes, superfused with medium equilibrated with 95% O2/5% CO2, was 27 +/- 3% (SE) (n = 78), comparable to that in beating whole heart. Increasing intracellular Ca2+ did not significantly change NAD reduction. NAD reduction decreased reversibly to 11 +/- 1% (n = 78) in contracting myocytes electrically paced at 5 Hz for 10 min. Oxygen uptake was stimulated fivefold. There was minimal change in sarcoplasmic pH measured by fluorescence of carboxy-seminaphthorhodafluor-1. However, NAD reduction increased reversibly in response to electrically paced contractions when: (a) myoglobin was inactivated with sodium nitrite (37 +/- 7%; n = 48); or (b) cells were more densely layered and gassed with 20% O2/5% CO2 (48 +/- 3%; n = 30). We conclude that (a) the ratio NADH/NAD is decreased in well-oxygenated cells with increased work; (b) steady-state NAD reduction is increased with increased work when oxygen delivery is limited; and (c) functional myoglobin ensures an oxygen supply to the mitochondria of working cells. 相似文献