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1.
Morphological and genetic variation at microsatellite loci of Caucasian shrew Sorex satunini Ogn. is examined and compared with that of the common shrew S. araneus L. Genetic distance at microsatellite loci between the common shrew and Caucasian shrew proved to be threefold higher than between chromosome races of the common shrew. The Caucasian shrew manifested low polymorphism in studies of both microsatellites and morphometric mandibular traits. The heterozygote deficit was also typical. These properties may be a consequence of partial isolation of the population and gene drift. 相似文献
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Multiannual variation is one of several types of species morphological variability, one that is directly related to ecophenotypic
and evolutionary responses to changing environments. The morphology of small mammal populations can change quickly because
generation length is short, usually one year, and individual lifespans are often only a year or two. We studied the response
of skull and mandible morphology in the common shrew Sorex araneus Linnaeus, 1758 to nine climate factors related to snow cover, temperature and precipitation at a study site near Syktyvkar,
Russia through the period 1976 to 2003. We found that these multivariate phenotypes changed significantly from year to year,
though there were no clear directional trends in the change. The phenotype itself was closely associated with the range of
annual temperature and winter precipitation. Changes in summer temperatures and precipitation seem to drive change in size-related
phenotypes, whereas changes in snow cover and winter temperature seem to drive change in shape. 相似文献
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O. V. Golovanova V. I. Konenkov A. V. Shevchenko M. V. Smolnikova 《Russian Journal of Genetics》2009,45(8):981-986
Based on population analysis of the DRB1, DQA1, DQB1 and TNFA allele frequency distribution patterns, regional features of immunogenetic structure of the population of West Siberia were
investigated. Statistically significant linkage disequilibrium within the HLA class II region, as well as between the TNFA and DRB1, DQA1, and DQB1 was demonstrated. Population frequency distribution patterns of two- and multilocus haplotypes were examined. 相似文献
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Following a re-examination of the material treated under Barleria brevispina (Fiori) Hedrén in the recent Flora of Somalia account of the Acanthaceae, it is concluded that two distinct species are involved and Barleria compacta Malombe & I. Darbysh. is described here from north-eastern Somalia. Its affinities and conservation status are discussed. 相似文献
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The life cycle and developmental stages of Aylax hypecoi (Trotter, 1913, Hymenoptera: Cynipidae: Aylacini) were studied in detail. Aylax hypecoi is known to induce galls in fruits of two Hypecoum species — H. imberbe and H. geslini (Papaveraceae) and the larva develops in host plant fruits. The morphology and development of egg, larva and pupa were investigated, which
has previously not been done. The shape and size of terminal-instar larvae and associated galls are sex-specific. Overwintering
stage, adult emergence and flying periods, and egg productivity were studied also. 相似文献
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There are three most important bacterial causative agents of serious infections that could be misused for warfare purposes:
Bacillus anthracis (the causative agent of anthrax) is the most frequently mentioned one; however, Fracisella tularensis (causing tularemia) and Yersinia pestis (the causative agent of plague) are further bacterial agents enlisted by Centers for Disease Control and Prevention into the category A of potential biological weapons. This review intends to summarize basic information about these bacterial
agents. Military aspects of their pathogenesis and the detection techniques suitable for field use are discussed. 相似文献
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Luciano Elias Oliveira Kátia G. Facure Ariovaldo A. Giaretta 《Environmental Biology of Fishes》2012,93(1):89-94
We present data on the habitat, density, and spatial distribution of Rivulus giarettai, and discuss some biotic and abiotic variables related to its abundance in Free Flowing Waters (FFW) and Dam Reservoirs (DR)
in palm grove (Mauritia flexuosa) marshes (Veredas) in Uberlandia, Minas Gerais, southeastern Brazil. The mean density (individuals/plot) of R. giarettai was about 13 times higher in FFW than in DR. In FFW, the density of R. giarettai was highest at intermediate amounts of substrate (plant mass) and it was positively rank-correlated with the depth, and the
number of arthropods. Individuals occurred in an aggregated distribution. The aggregated pattern could be related to a concentration
of individuals in microhabitats neither too much exposed nor completely saturated by plants. R. giarettai was relatively abundant and tolerant to slight man-made habitat modifications. Damming appeared to be especially problematic
by negatively affecting its density. 相似文献
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Summary. The paper describes two methods of the synthesis of ethyl (3R,4S)- and (3S,4S)-4-[(benzyloxycarbonyl)amino]-5-[(tert-butyloxycarbonyl)amino]-3-hydroxypentanoates, useful for the syntheses of edeine analogs. Differently N-protected (S)-2,3-diaminopropanoic acid was used as a substrate in both procedures. The absolute configuration of newly generated asymmetric
carbon atoms C-3 in β-hydroxy-γ,δ-diamino products was assigned by means of 1H NMR spectroscopy after their transformation into corresponding piperidin-2-ones.
Received May 24, 2002 Accepted October 10, 2002 Published online December 18, 2002
Acknowledgment The authors are indebted to the Faculty of Chemistry, Technical University of Gdańsk for financial support.
Authors' address: Zbigniew Czajgucki, M. Sc., Department of Pharmaceutical Technology and Biochemistry, Faculty of Chemistry, Technical University
of Gdańsk, 11/12 Narutowicza St., 80-952 Gdańsk, Poland, Fax +48 58 347 11 44, E-mail: zmczaj@wp.pl 相似文献
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N. Yu. Markelova 《Microbiology》2010,79(6):777-779
Interaction of Bdellovibrio bacteriovorus 100NCJB with bacteria Campylobacter jejuni (strains 1, 2, 3, 4, and 5) and Helicobacter pylori, strain TX30a, was confirmed. The results indicate that lytic activity of bdellovibrios both in liquid media and cells attached
to a surface was observed. The potential use of the antimicrobial activity of predatory bacteria for environmental bioprotection
and public health is discussed. 相似文献
13.
ITS sequences determined for 53 Erysiphe specimens on Syringa and Ligustrum collected in Europe, East Asia, and North and South America were divided into two ITS groups, S and K types. Phylogenetic
analysis showed that these two ITS types do not share a common ancestor and form separate clades. The K type on Ligustrum was identified as Erysiphe ligustri based on the three-dimensional branching pattern of appendages. Morphological observations showed that there are some morphological
differences—pigmentation of appendages and number of ascospores per ascus—between the S and K types on Syringa. Based on these morphological observations, the S and K types on Syringa were identified as E. syringae and E. syringae-japonicae, respectively. The recent abundant production of chasmothecia by lilac powdery mildew in Europe was caused by E. syringae-japonicae introduced from East Asia. DNA sequence analyses of the rDNA ITS region and the 28S rDNA, tub2, CYP51, and Chs1 genes did not support an interspecific hybrid origin for E. syringae-japonicae. Haplotype analysis suggested that E. syringae originated in North America and independently migrated to East Asia and Europe/South America. 相似文献
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The internal transcribed spacer (ITS) region was sequenced in symbiotic dinoflagellates (zooxanthellae) from five morphospecies in the genus Madracis. The phylogeny of the symbionts is congruent with a companion phylogeny of the coral host. Comparison with known clade B symbiont ITS types reveals that M. mirabilis contains the B13 symbiont and that the other morphospecies contain the B7 symbiont. Madracis formosa also contains a previously undescribed type. The B7 and B13 symbionts appear to be highly specific to morphospecies in the genus Madracis. The host specificity between the B13 symbionts and its coral host may be the result of co-evolution of the coral-symbiont association and suggests that the brooding species, M. mirabilis, is reproductively isolated. Microhabitat differentiation associated with light utilization independent of depth is discussed. 相似文献
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Matthieu F Faure Patrice David François Bonhomme Nicolas Bierne 《BMC evolutionary biology》2008,8(1):164
Background
Few models of genetic hitchhiking in subdivided populations have been developed and the rarity of empirical examples is even more striking. We here provide evidences of genetic hitchhiking in a subdivided population of the marine mussel Mytilus edulis. In the Bay of Biscay (France), a patch of M. edulis populations happens to be separated from its North Sea conspecifics by a wide region occupied only by the sister species M. galloprovincialis. Although genetic differentiation between the two M. edulis regions is largely non-significant at ten marker loci (average FST~0.007), a strong genetic differentiation is observed at a single locus (FST = 0.25). We validated the outlier status of this locus, and analysed DNA sequence polymorphism in order to identify the nature of the selection responsible for the unusual differentiation. 相似文献16.
I. Rosario G. Soro S. Déniz O. Ferrer F. Acosta D. Padilla B. Acosta 《Mycopathologia》2010,169(4):315-319
Columba livia is an important reservoir and carrier of Cryptococcus neoformans, Cryptococcus uniguttulatus, Cryptococcus laurentii and Cryptococcus albidus. Upper digestive tract of this species is also known as a habitat for Cryptococcus neoformans. Given the increasing clinical interest of this microorganism, 331 swabs from crop and 174 dropping samples from pigeon lofts
in Grand Canary Island have been studied. The obtained results show an extensive presence samples 81 positive (24.47%) of
Cryptococcus spp. in analysed crops: 32 (9.66%) for C. neoformans, 24 (7.2%) for C. uniguttulatus, 23 (6.9%) for C. albidus and 2 (0.6%) for C. laurentii. In the same way, Cryptococcus spp was also isolated in 82 (47.13%), dropping samples: C. neoformans in 59 (33.9%), C. uniguttulatus, in 9 (5.17%), C. laurentii in 8 (4.59%) and C. albidus in 6 (3.44%) of the investigated samples, respectively. The cryptococcosis produced by species of cryptococci other than C. neoformans has become more important during the last decade, supporting the study on the role of pigeon in the epidemiology of this
disease. 相似文献
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Marcin Sielezniew Izabela Dziekańska Anna M. Stankiewicz-Fiedurek 《Journal of Insect Conservation》2010,14(2):141-149
Phengaris (=Maculinea) arion is an endangered social parasite of Myrmica ants, and for a very long time was considered as specific to Myrmica sabuleti. Previous studies carried out in Poland suggested some discrepancies within this assumption, and therefore a much more intensive
survey was undertaken. The host ant use of P. arion was studied at five sites in different types of biotopes in Poland, i.e. xerothermal grasslands where Thymus pulegioides was used as a larval food plant by the butterfly, and more or less sandy biotopes with Thymus serpyllum. Altogether nine Myrmica species were recorded, and considerable variation in species composition and density of nests was recorded. At four localities
M. sabuleti proved to be the most common ant. A total of 529 Myrmica nests were examined, and only 20 of them contained larvae and pupae of P. arion. Host ants belonged to five different species, i.e. M. sabuleti, Myrmica scabrinodis, Myrmica schencki, Myrmica lobicornis and Myrmica hellenica. Only at one site (NE Poland) was a significant heterogeneity in parasitation rates among Myrmica species detected. M. lobicornis was the most often infested ant there, which may suggest local specialisation of the butterfly. Overall low parasitism rates
may explain the vulnerability of P. arion in Central Europe but further studies are also necessary. 相似文献
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S. E. Dawson 《Kew Bulletin》2008,63(3):517-517
Summary The name Pavetta modesta (Hiern) S. E. Dawson is a later homonym of P. modesta Bremek. Pavetta crystalensis is proposed as a new name. 相似文献
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Reinerio Benega Garcia Aroldo Cisneros Bert Schneider Noemi Tel-Zur 《Plant cell reports》2009,28(5):719-726
Gynogenesis was investigated on the allotetraploid Selenicereus megalanthus and the diploid Hylocereus polyrhizus and Hylocereus undatus vine cactus species. Unpollinated ovules from developing flower buds containing microspores at middle uninucleate developmental
stage were cultured on MS basal medium containing 2,4-D/TDZ with different sucrose concentrations. Ovule size increased under
dark culture conditions in all the three species and the level of response was species and sucrose concentration dependent.
The best responses were achieved in the two S. megalanthus accessions, E-123 and J-80, at 0.18 and 0.26 M sucrose. Only ovule enlargement was obtained in H. undatus and both ovule enlargement and callus were obtained in H. polyrhizus. Development in both species ceased and embryoids were not formed. Plant regeneration was directly and indirectly obtained
in both S. megalanthus accessions. Ploidy level was determined for a total of 29 S. megalanthus gynogenic plants using flow cytometry: 15 were found to be dihaploid (plants with the gametophytic chromosome number) and
the other 14 were found to have higher ploidy levels. This is the first report of successful gynogenesis in Cactaceae. The
dihaploids of S. megalanthus successfully produced by ovule culture techniques opens new perspectives in vine cacti breeding. 相似文献
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