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对鞑靼滨藜全草的挥发性化学成分进行分析。采用水蒸气蒸馏法及索氏提取法提取鞑靼滨藜全草中的挥发性化学成分,用GC-MS联用技术分析其化学组成,计算其相对百分含量,并对两种提取方法进行比较研究。结果表明:水蒸气蒸馏法提取物的成分比索氏提取法较多。从水蒸气蒸馏法分离出的53个色谱峰中鉴定了51种成分,含量最高的是茴香脑(45.84%),其次为正二十七烷(9.28%),羟基吲哚(6.81%),α-羟基-2-甲基丙基苯乙酸酯(4.03%)。从索氏提取法分离出的26个色谱峰中鉴定了22种成分,含量最高的是正二十九烷(22.63%),其次为硬酯酸(16.69%),十六醛(6.89%),棕榈酸(5.43%)。 相似文献
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This study was designed to examine the nursing patterns and related behavior of young saiga raised by their dams. Four captive born lambs were observed at weekly intervals during continuous 14 h watches for the first 7 weeks of life. One-week-old lambs were found to nurse at an average rate of 1.1 bouts per hour and nursed for an average of 14.6 seconds per bout. This high nursing frequency and the average total daily nursing time of 242 seconds decreased rapidly with age. Saiga lambs sampled solid food as early as 4 days of age and were nearly dependent on solid food by the age of 7 weeks. Communal nursing, in which one or more lambs would nurse from an unrelated adult female while she nursed her own, was common. Grooming of the lamb by the dam was never seen except immediately following birth. © 1994 Wiley-Liss, Inc. 相似文献
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The genomic distribution of microsatellites can be explained by DNA slippage, slippage like processes and base substitutions. Nevertheless, microsatellites are also frequently associated with repetitive DNA, raising the question of the relative contributions of these processes to microsatellite genesis. We show that in Silene tatarica about 50% of the microsatellites isolated by an enrichment cloning protocol are associated with repetitive DNA. Based on the flanking sequences, we distinguished seven different classes of repetitive DNA. PCR primers designed for the flanking sequences of an individual clone amplified a heterogeneous family of repetitive DNA. Despite considerable variation in the flanking sequence (pi = 0.108), the microsatellite repeats did not show any evidence for decay. Rather, we observed the emergence of a new repeat type that probably arose by mutation and was spread by replication slippage. In fact, a complete repeat type switch could be observed among the analysed clones. We propose that the analysis of microsatellite sequences embedded in repetitive DNA provides a hitherto largely unexplored tool to study microsatellite evolution. 相似文献
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从鞑靼滨藜(Atriplex tatarica)首次分离得到6个化合物,通过理化及波谱分析,它们分别确定为苜素(tricin,1),苜蓿素-7-O-β-D-吡喃葡萄糖苷(tricin 7-O-β-D-glucopyranoside,2),异鼠李素(isorhanmetin,3),异鼠李素.3-芸香糖甙(Isorhamnetin-3-rutinoside,4),豆甾醇(stigmasteml,5),β-谷甾醇(β-sitosterol,6)。 相似文献
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Five new microsatellite loci were isolated from the perennial plant, Silene tatarica. We characterized S. tatarica individuals originating from two riverbank populations in northern Finland and observed between four and nine alleles per locus. Observed heterozygosity was consistently lower than gene diversity (HO: 0.0450–0.2385, HE: 0.1919–0.6187). This deficiency of heterozygous genotypes was observed in most locus/population combinations, and is presumably caused by spatial genetic structuring due to restricted seed flow within subpopulations. The markers presented here are the first microsatellites reported for S. tatarica. 相似文献
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为了解世界濒危物种、国家Ⅰ级保护野生动物赛加羚羊(Saiga tatarica)主要器官组织的结构特征,本研究利用石蜡组织切片技术,对1只因胎衣不下死亡的雌性成年赛加羚羊心、肝、脾、肺、肾的组织结构进行了观察。赛加羚羊心肌纤维发达,呈圆柱状,有分支,其胞核位于细胞边缘,各心肌纤维分支末端相互连接构成肌纤维网,闰盘明显。肝组织致密,间质少,肝小叶分界不清,切面呈不规则的多边形,肝细胞以中央静脉为中心呈放射状排列。脾的被膜较厚,脾小梁由被膜和脾门的结缔组织伸入脾实质形成,相互连接构成脾的粗支架;实质部分可明显分为白髓和红髓,白髓主要分布在脾内小动脉周围,其内部脾小结形状为圆形或椭圆形;红髓主要分布于白髓区周围,其内充满大量的红细胞。肺实质导气部主要可见细支气管和终末细支气管,其中,细支气管的管腔面富含纵行皱襞,黏膜上皮为假复层柱状纤毛上皮;呼吸部可见大量的肺泡管、肺泡囊和肺泡,肺泡结构清晰可见。肾为平滑单乳头肾,由被膜和实质构成,实质可明显分为皮质与髓质,皮质内可见大量肾小体和少量结缔组织。总体而言,与其他同类型反刍动物相比较,赛加羚羊各主要器官的组织结构未见有明显差异。 相似文献
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Aspi J Jäkäläniemi A Tuomi J Siikamäki P 《Evolution; international journal of organic evolution》2003,57(3):509-517
This study partitions selection in a natural metapopulation of a riparian plant species, Silene tatarica, into individual- and patch-level components by using contextual analysis, in which a patch refers to a spatially distinct stand of individual plants. We estimated selection gradients for two morphological characters (plant height and number of stems), their respective patch means, and plant density with respect to reproductive success in a two-year study. The approach was also extended to partition selection separately within habitats with varying degrees of exposure to river disturbances and herbivory. The selection differentials and gradients for plant height were positive at both individual and patch levels, with selection forces highest in the closed habitat with low exposure to disturbance. This pattern suggests that local groups with taller than average plants are more visible to pollinators than to groups that are shorter than average plants; and, within patches, individuals with short stature are visited less often than taller ones. Selection on the number of stems was in opposition at individual and patch levels. At the individual level the character was selected toward higher values, whereas selection at the patch-level favored smaller mean number of stems. The strength of the latter component was associated with the intensity of herbivory in different habitats, suggesting that the patch-level selection against a large number of stems might be due to high attractiveness of such patches to the main herbivore, reindeer. Consequently, direction and strength of selection in spatially structured populations may depend significantly on fitness effects arising at the group level. 相似文献
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We describe an efficient process for the regeneration of Lonicera tatarica plants from cultured stem sections. Induction of multiple shoots was achieved directly from cultured stem cuttings. The highest regeneration rate was achieved on Gamborg's B5 medium supplemented with 4% sucrose and 0.8% Difco bacto-agar in the absence of hormones. Differentiated shoots were elongated for 5-7 days on induction medium supplemented with 0.5 mg/l GA3. Shoot induction and elongation experiments were carried out using original stem explants from either 2-, 6-, or 18-month-old donor plants. The age of the donor plant had no noticeable effect on either process. However, rooting of elongated shoots occurred only with shoots derived from 2-month-old donor plants. Rooting efficiency and proliferation were highest on half-strength WPM medium supplemented with 2 µM indole-3-butyric acid and 0.6% Keylis agar. The plants regenerated from stem explants were morphologically normal, and levels of loganin and secologanin were comparable to those detected in plants grown from seed and maintained through vegetative propagation. 相似文献
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2018年4月下旬至5月初对国家林业局甘肃濒危动物保护中心的61只初生赛加羚羊(Saiga tatarica)成活率、性别比例、单双羔比例、初生重等生物学数据进行了观测,并对结果进行归纳分析。赛加羚羊分娩期始于4月25日,截止于5月5日,产羔高峰期集中在4月28日至5月2日。共分娩61只羔羊,成活56只,成活率91.80%。其中,雄性羔羊占40.98%,雌性羔羊占59.02%,雌雄性别比(♀︰♂)为1.44︰1,与1︰1的性比差异不显著(χ2检验,P> 0.05);单羔比例80.33%,双羔比例19.67%,两者差异极显著(P <0.01);初生羔羊体重多数集中在2.501~3.000 kg,雄性羔羊平均初生重略高于雌性羔羊,单羔羚羊平均体重略高于双羔羚羊。单羔雄羚羊与双羔雄羚羊、单羔雌羚羊与双羔雌羚羊以及单双羔、雌雄羔羊总平均体重间的差异均不显著(P> 0.05)。 相似文献
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Ilya A. Volodin Olga V. Sibiryakova Lyudmila E. Kokshunova Roland Frey Elena V. Volodina 《Bioacoustics.》2013,22(2):79-98
The trunk-like nose of the saiga antelope Saiga tatarica is a striking example of an exaggerated trait, assumed to having evolved as a dust filter for inhaled air. In addition, it functions to elongate the vocal tract in harem saiga males for producing low-formant calls that serve as a cue to body size for conspecifics. This study applies the source–filter theory to the acoustics of nasal, oral and nasal-and-oral calls that were recorded from a captive herd of 24 mother and 32 neonate saigas within the first 10 days postpartum. Anatomical measurements of the nasal and oral vocal tracts of two specimens (one per age class) helped to establish the settings for the analysis of formants. In both mother and young, the lower formants of nasal calls/call parts were in agreement with the source–filter theory, which suggests lower formants for the longer nasal vocal tract than for the shorter oral vocal tract. Similar fundamental frequencies of the nasal and oral parts of nasal-and-oral calls were also in agreement with the source–filter theory, which postulates the independence of source and filter. However, the fundamental frequency was higher in oral than in nasal calls, probably due to the higher emotional arousal during the production of oral calls. We discuss production mechanisms and the ontogeny of formant patterns of oral and nasal calls among bovid and cervid species with and without a trunk-like nose. 相似文献
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BACKGROUND AND AIMS: Genetic variability was estimated for Atriplex tatarica from 25 populations in the Czech Republic. Since its north-western range margin is in central Europe, a relationship between marginality and low within-population genetic diversity was tested in accordance with the Central-Marginal Model. METHODS: Population genetic diversity was expressed by assessing patterns of variation at 13 putatively neutral allozyme loci (comprising 30 putative alleles) within and between 25 natural populations of A. tatarica along a north-west-south-east transect in the Czech Republic. KEY RESULTS: Atriplex tatarica is a species of human-made habitats with a mixed mating system and wide geographic distribution. Overall, A. tatarica displayed moderate levels of genetic diversity in comparison with other herbaceous plants. The percentage of loci that were polymorphic was 47.1%, with average values of 1.55, 0.151 and 0.155 for the average number of alleles per polymorphic locus (A), observed heterozygosity (Ho) and expected heterozygosity (He), respectively. There was only weak evidence of inbreeding within populations (FIS=0.031) and significant population differentiation (FST=0.214). Analysis of the data provides no evidence for isolation-by-distance for the whole study area. However, Mantel tests were highly significant for the marginal Bohemian region and non-significant for the central Moravian region. While northern populations of A. tatarica showed significantly lower allelic richness (A=1.462) than populations from the southern part of the study area (A=1.615), they did not differ in observed heterozygosity (Ho), gene diversity (HS), inbreeding within populations (FIS) or population differentiation (FST), despite generally lower values of particular genetic measurements in the marginal region. CONCLUSIONS: Genetic diversity, with the exception of allelic richness, was not significantly lower at the margins of the species' range. This, therefore, provides only weak support for the predictions of the Central-Marginal Model. 相似文献
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Local genetic population structure in an endangered plant species, Silene tatarica (Caryophyllaceae)
Genetic substructuring in plant populations may evolve as a consequence of sampling events that occur when the population is founded or regenerated, or if gene dispersal by pollen and seeds is restricted within a population. Silene tatarica is an endangered, perennial plant species growing along periodically disturbed riverbanks in northern Finland. We investigated the mechanism behind the microspatial genetic structure of S. tatarica in four subpopulations using amplified fragment length polymorphism markers. Spatial autocorrelation revealed clear spatial genetic structure in each subpopulation, even though the pattern diminished in older subpopulations. Parentage analysis in an isolated island subpopulation indicated a very low level of selfing and avoidance of breeding between close relatives. The mean estimated pollen dispersal distance (24.10 m; SD = 10.5) was significantly longer and the mean seed dispersal distance (9.07 m; SD = 9.23) was considerably shorter than the mean distance between the individuals (19.20 m; SD = 13.80). The estimated indirect and direct estimates of neighbourhood sizes in this subpopulation were very similar, 32.1 and 37.6, respectively. Our results suggested that the local spatial genetic structure in S. tatarica was attributed merely to the isolation-by-distance process rather than founder effect, and despite free pollen movement across population, restricted seed dispersal maintains local genetic structure in this species. 相似文献
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Genetic structure and gene flow in a metapopulation of an endangered plant species,Silene tatarica 总被引:1,自引:0,他引:1
We investigated the distribution of genetic variation within and between seven subpopulations in a riparian population of Silene tatarica in northern Finland by using amplified fragment length polymorphism (AFLP) markers. A Bayesian approach-based clustering program indicated that the marker data contained not only one panmictic population, but consisted of seven clusters, and that each original sample site seems to consist of a distinct subpopulation. A coalescent-based simulation approach shows recurrent gene flow between subpopulations. Relative high FST values indicated a clear subpopulation differentiation. However, amova analysis and UPGMA-dendrogram did not suggest any hierarchical regional structuring among the subpopulations. There was no correlation between geographical and genetic distances among the subpopulations, nor any correlation between the subpopulation census size and amount of genetic variation. Estimates of gene flow suggested a low level of gene flow between the subpopulations, and the assignment tests proposed a few long-distance bidirectional dispersal events between the subpopulations. No apparent difference was found in within-subpopulation genetic diversity among upper, middle and lower regions along the river. Relative high amounts of linkage disequilibrium at subpopulation level indicated recent population bottlenecks or admixture, and at metapopulation levels a high subpopulation turnover rate. The overall pattern of genetic variation within and between subpopulations also suggested a 'classical' metapopulation structure of the species suggested by the ecological surveys. 相似文献