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1.
mtDNA diversity in rhesus monkeys reveals overestimates of divergence time and paraphyly with neighboring species 总被引:4,自引:0,他引:4
Reconstructions of the human-African great ape phylogeny by using
mitochondrial DNA (mtDNA) have been subject to considerable debate. One
confounding factor may be the lack of data on intraspecific variation. To
test this hypothesis, we examined the effect of intraspecific mtDNA
diversity on the phylogenetic reconstruction of another Plio- Pleistocene
radiation of higher primates, the fascicularis group of macaque (Macaca)
monkey species. Fifteen endonucleases were used to identify 10 haplotypes
of 40-47 restriction sites in M. mulatta, which were compared with similar
data for the other members of this species group. Interpopulational,
intraspecific mtDNA diversity was large (0.5%- 4.5%), and estimates of
divergence time and branching order incorporating this variation were
substantially different from those based on single representatives of each
species. We conclude that intraspecific mtDNA diversity is substantial in
at least some primate species. Consequently, without prior information on
the extent of genetic diversity within a particular species, intraspecific
variation must be assessed and accounted for when reconstructing primate
phylogenies. Further, we question the reliability of hominoid mtDNA
phylogenies, based as they are on one or a few representatives of each
species, in an already depauperate superfamily of primates.
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2.
Aftanas LI Reva NV Savotina LN Makhnev VP 《Rossi?skii fiziologicheski? zhurnal imeni I.M. Sechenova / Rossi?skaia akademiia nauk》2004,90(12):1457-1471
The present study addressed EEG pattering during experimentally manipulated emotion. Film clips previously shown to induce happiness,joy, anger, disgust, fear/anxiety, sadness, as well as neutral control films, were presented to 30 university students while a 62-channel EEG was recorded, and a self-reported effect was described. Analyses revealed both emotion-specific and emotion-unspecific EEG pattering for the emotions under study. Induced positive and negative emotions were accompanied by hemispheric activation asymmetries in theta-2, alpha-2, and beta-1 EEG frequency bands. Emotions of joy and disgust induced lateralized a theta-2 power increase in anterior-temporal and frontal regions of the left hemisphere reflecting involvement of cognitive mechanisms in the emotional processing. Negative emotions of disgust and fear/anxiety were characterized by alpha-2 and beta-1 desynchronization of the right temporal-parietal cortex, suggesting its involvement in modulation of the emotion-related arousal. 相似文献
3.
During the chronic water epidemic of typhoid fever in Tajikistan in 1996-1997 specific features of the epidemic process dynamics in groups of servicemen were studied in several cities. The infective agent was proved to be transmitted by the alimentary route and through everyday contacts, the water route of transmission playing the most important role. The early clinical and epidemiological signs of the water outbreak of typhoid fever and the risk factors were established. The clinical and epidemiological aspects of vaccination were analyzed. 相似文献
4.
M V Makhnev 《Antibiotiki i khimioterapii͡a》2003,48(4):27-34
During superepidemic of a typhoid fever in Tadjikistan the efficiency of application in clinics and of 14 antimicrobial agents representing almost all basic chemical classes was investigated. Remarkable variation of frequency and type of S. typhi resistance to these preparations up to epidemic and especially in its process was demonstrated. The absence of absolute (100%) efficacy of the investigated agents in vivo and in vitro was shown. The reasons of low efficacy of etiotropic treatment of the patients with typhoid fever are analysed. 相似文献
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6.
The paper gives short characteristics of the main stages of forming the strategy of restoration of the industrially disturbed
lands and their monitoring, along with the examples of its successful use. 相似文献
7.
Changes in the content of dammarane-type triterpene alcohols in the leaves of silver birch (Betula pendula Roth) are studied for the first time along a zonal-climatic transect from the northern to southern borders of the species
areal in the Trans-Ural region. It is shown that populations of northern and southern regions differ concerning the triterpene
content in leaves. A correlation between the content of triterpene alcohols in silver birch leaves and some climatic parameters
is revealed. At the same time, the range of the intrapopulation variability of triterpene content is significantly less than
that of the interpopulation variability, which indicates a high potential of population selection on the basis of this biochemical
parameter. 相似文献
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9.
Jane L Wagstaff Jonathan N Pruneda Stefan MV Freund David Komander 《The EMBO journal》2017,36(24):3555-3572
The Ser/Thr protein kinase PINK1 phosphorylates the well‐folded, globular protein ubiquitin (Ub) at a relatively protected site, Ser65. We previously showed that Ser65 phosphorylation results in a conformational change in which Ub adopts a dynamic equilibrium between the known, common Ub conformation and a distinct, second conformation wherein the last β‐strand is retracted to extend the Ser65 loop and shorten the C‐terminal tail. We show using chemical exchange saturation transfer (CEST) nuclear magnetic resonance experiments that a similar, C‐terminally retracted (Ub‐CR) conformation also exists at low population in wild‐type Ub. Point mutations in the moving β5 and neighbouring β‐strands shift the Ub/Ub‐CR equilibrium. This enabled functional studies of the two states, and we show that while the Ub‐CR conformation is defective for conjugation, it demonstrates improved binding to PINK1 through its extended Ser65 loop, and is a superior PINK1 substrate. Together our data suggest that PINK1 utilises a lowly populated yet more suitable Ub‐CR conformation of Ub for efficient phosphorylation. Our findings could be relevant for many kinases that phosphorylate residues in folded protein domains. 相似文献
10.
Morphometric parameters of mature leaves (area, venation density, and shape coefficient) and trunks (size and biomass) of
two edificatory birch species, Betula pendula Roth and B. pubescens Ehrh., were characterized. These species inhabit a 1600-km transect of the Urals, from forest-tundra to forest-steppe. In
both species, the highest trunk biomass was observed in the subzone of south taiga. Trunk parameters and leaf sizes of B. pendula varied in a narrower range than in B. pubescens. As distinct from leaf shape, leaf size was correlated with the average multiyear climate characteristics but not with the
weather during a given growth season. In B. pubescens, which range extends wide from its climatic optimum, leaf area was positively correlated with trunk biomass. In B. pendula, growing mainly within the area of its climatic optimum, such correlation was not observed. We concluded that such parameter
as mature leaf size could be used for prediction of tree productivity growing outside of the zone of their climatic optimum. 相似文献