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111.
Dmitry A. German Wen‐Li Chen Sergey V. Smirnov Bing Liu Maxim G. Kutzev Jian Wang Alexander I. Shmakov Rudolph V. Kamelin 《Nordic Journal of Botany》2012,30(1):61-69
Two genera new to China, Fibigia and Pachyneurum and 10 species found in China for the first time, Puccinellia kalininae, Stellaria pulvinata, Nanophyton mongolicum, Capsella orienalis, Pachyneurum grandiflorum, Fibigia spathulata, Craniospermum tuvinicum, Euphrasia schischkinii, E. syreitschikovii, Veronica schmakovii along with 3 species previously unknown in Xinjiang, Rorippa indica, Acalypha australis, and Phalaris canariensis, found in northwest Xinjiang are reported. In addition, the distribution of two species in China is corrected: Lepidium densiflorum is firstly reported for Nei Mongol while the occurrence of Draba sibirica in Gansu is not confirmed. Results of floristic studies by the Chinese–Russian Altai expedition during 2004–2007 are also summarized including 34 species and 1 subspecies revealed as new for China; 7 species confirmed to occur in China; one genus and 5 species not confirmed for China, as well as a number of new records for various provinces, mostly Xinjiang. 相似文献
112.
JINDŘIŠKA BOJKOVÁ KLÁRA KOMPRDOVÁ TOMÁŠ SOLDÁN SVĚTLANA ZAHRÁDKOVÁ 《Freshwater Biology》2012,57(12):2550-2567
1. Rapid expansion and intensification of anthropogenic activities in the 20th century has caused profound changes in freshwater assemblages. Unfortunately, knowledge of the extent and causes of species loss (SL) is limited due to the lack of reliable historical data. An unusual data set allows us to compare changes in the most sensitive of aquatic insect orders, the Plecoptera, at some 170 locations in the Czech Republic between two time periods, 1955–1960 and 2006–2010. Historical data (1890–1911) on assemblages of six lowland rivers allow us to infer even earlier changes. 2. Regional stonefly diversity decreased in the first half of the 20th century. Streams at lower altitudes lost a substantial number of species, which were never recovered. In the second half of the century, large‐scale anthropogenic pressure caused SL in all habitats, leading to a dissimilarity of contemporary and previous assemblages. The greatest changes were found at sites affected by organic pollution and a mixture of organic pollution and channelisation or impoundment. Colonisation of new habitats was observed in only three of the 80 species evaluated. 3. Species of moderate habitat specialisation and tolerance to organic pollution were most likely to be lost. Those with narrow specialisations in protected habitats were present in both historical and contemporary collections. 4. Contemporary assemblages are the consequence of more than a 100 years of anthropogenic impacts. In particular, streams at lower altitude and draining intensively exploited landscapes host a mere fragment of the original species complement. Most stonefly species are less frequently present than before, although their assemblages remain almost intact in near‐natural mountain streams. Our analyses demonstrate dramatic restriction of species ranges and, in some cases, apparent changes in altitudinal preference throughout the area. 相似文献
113.
E. A. Khomyakova E. M. Zubin L. V. Pavlova E. V. Kazanova I. P. Smirnov G. E. Pozmogova S. Muller N. G. Dolinnaya E. A. Kubareva R. K. Hartmann T. S. Oretskaya 《Russian Journal of Bioorganic Chemistry》2012,38(5):488-499
1,2-Diol-oligoribonucleotides were prepared using fully protected 2??-O-[2-(2,3-dihydroxypropyl)amino-2-oxoethyl]uridine 3??-phosphoramidite. Incorporation of the modified uridine residue into oligonucleotide chains was not shown to significantly affect the thermal stability of RNA-RNA and RNA-DNA duplexes. Periodate oxidation of the 1,2-diol group resulted in reactive 2??-aldehyde oligoribonucleotides. These oligonucleotides were studied for their application in the affinity modification of RNA recognizing proteins with an example of bacterial ribonuclease P. 相似文献
114.
A. V. Stepanov A. A. Belogurov A. E. Mamedov D. Melamed I. V. Smirnov E. S. Kuzina D. D. Genkin A. N. Boyko S. N. Sharanova A. Bacon N. A. Ponomarenko A. G. Gabibov 《Russian Journal of Bioorganic Chemistry》2012,38(3):266-273
Multiple sclerosis (MS) is a severe autoimmune neurodegenerative disease. It attacks mainly young people. The development of new approaches to MS treatment is a challenge to modern immunology and pharmacology. In the present study, a high therapeutic efficacy of immunodominant peptides of myelin basic protein (MBP) incorporated into unilamellar mannosylated liposomes in the development of experimental autoimmune encephalomyelitis (EAE) is demonstrated in DA rats. MBP is a component of the oligodendrocyte membrane, which forms the axonal sheath. This protein is among the major autoantigens in MS. We have analyzed the binding pattern of anti-MBP autoantibodies from MS patients using a previously designed MBP epitope library. Utilizing the same approach, we have investigated the pool of anti-MBP antibodies from SJL/J and C57BL/6mice and DA rats with EAE. According to the autoantibody binding patterns, the rodent model most closely mimicking MS is EAE in DA rats. We have chosen three immunodominant MBP fragments encapsulated in unilamellar mannosylated liposomes for the treatment of the verified DA rodent model. MBP fragment 46?C62 is the most efficient in mitigating the first EAE attack, whereas MBP 124?C139 and 147?C160 inhibit the development of pathology at the regression stage. Simultaneous administration of these peptides in liposomes significantly reduces the level of antibodies against MBP. The synergistic therapeutic effect of MBP fragments reduces the integral disease score by inhibiting the first EAE attack and mitigating the subsequent relapse. Thus, our findings offer new opportunities for the efficient treatment of multiple sclerosis. 相似文献
115.
The Revised Classification of Eukaryotes 总被引:1,自引:0,他引:1
Sina M. Adl Alastair G. B. Simpson Christopher E. Lane Julius Lukeš David Bass Samuel S. Bowser Matthew W. Brown Fabien Burki Micah Dunthorn Vladimir Hampl Aaron Heiss Mona Hoppenrath Enrique Lara Line le Gall Denis H. Lynn Hilary McManus Edward A. D. Mitchell Sharon E. Mozley‐Stanridge Laura W. Parfrey Jan Pawlowski Sonja Rueckert Laura Shadwick Conrad L. Schoch Alexey Smirnov Frederick W. Spiegel 《The Journal of eukaryotic microbiology》2012,59(5):429-514
This revision of the classification of eukaryotes, which updates that of Adl et al. [J. Eukaryot. Microbiol. 52 (2005) 399], retains an emphasis on the protists and incorporates changes since 2005 that have resolved nodes and branches in phylogenetic trees. Whereas the previous revision was successful in re‐introducing name stability to the classification, this revision provides a classification for lineages that were then still unresolved. The supergroups have withstood phylogenetic hypothesis testing with some modifications, but despite some progress, problematic nodes at the base of the eukaryotic tree still remain to be statistically resolved. Looking forward, subsequent transformations to our understanding of the diversity of life will be from the discovery of novel lineages in previously under‐sampled areas and from environmental genomic information. 相似文献
116.
Experimental methods in lichenology are summarized, the most attention being paid to the synthetic and cultural methods. Synthetic methods are based on the several stages: induction of dissociation of the natural lichen thallus to the monocultures of symbionts, culturing of these symbionts, and subsequent resynthesis under controlled conditions. Synthesis of the model association is based on monocultures of one of the symbionts and free-living organisms. These methods allow studying specificity and selectivity of interactions among symbionts, morphogenesis of the lichen thallus, and the role of minor components of the symbiotic system. Cultural methods involve development of dedifferentiated cell aggregates of lichen thallus ("lichen tissue cultures") on the solid and liquid media. At present, the methods of maintenance of lichen tissue cultures on the solid medium are worked out only. However, the lichen tissue cultures on the liquid medium are much more interesting because this method can be introduced in biotechnology. Cultural methods allow to achieve lichen biomass that contain specific lichen compounds. Induction of morphogenesis in lichen tissue cultures is possible. 相似文献
117.
Sea Cucumbers Triterpene Glycosides, the Recent Progress in Structural Elucidation and Chemotaxonomy
Vladimir I. Kalinin Alexandra S. Silchenko Sergey A. Avilov Valentin A. Stonik Alexey V. Smirnov 《Phytochemistry Reviews》2005,4(2-3):221-236
Triterpene glycosides are characteristic metabolites of sea cucumbers (Holothurioidea, Echinodermata). Majority of the glycosides
belong to holostane type (lanostane derivatives with 18(20)-lactone). Carbohydrate chains of these glycosides contain xylose,
glucose, quinovose, 3-O-methylglucose and 3-O-methyl sylose. During the last 5 years, main investigations were focused on holothurians belonging to the order Dendrochirotida
collected in the North Pacific, North Atlantic, Antarctic and in subtropical waters. The glycosides of holothurians belonging
to the order Aspidochirotida have also been studied. The most uncommon structural features of carbohydrate chains of new glycosides
were: (1) the presence of quinovose as fifth terminal monosaccharide unit and the presence of two quinovose residues; (2)
the presence of glucose instead of common xylose as fifth terminal monosaccharide unit; (3) trisaccharide carbohydrate chain;
(4) the presence of two 3-O-methylxylose terminal monosaccharide units; (5) the presence of sulfate group at C-3 of quinovose residue. New glycosides
without lactone or with 18(16)-lactone and having shortened side chains have also been isolated. The presence of 17α and 12α-hydroxyls,
which are characteristic for glycosides from holothurians belonging to the family Holothuriidae (Aspidochirotida) in glycosides
of dendrochirotids confirms parallel and relatively independent character of evolution of glycosides. All three families belonging
to the order Aspidochirotida: Holothuriidae, Stichopodidae and Synallactidae have similar and parallel trends in evolution
of the glycosides carbohydrate chains, namely from non-sulfated hexaosides to sulfated tetraosides. Sets of aglycones in glycosides
from holothurians belonging to the genus Cucumaria (Cucumariidae, Dendrochirotida) are specific for each species. The carbohydrate chains are similar in all representatives
of the genus Cucumaria. 相似文献
118.
Integration of molecular and cytegenetic levels of investigation results in complex understanding of structural and functional genome organization. Gridded libraries of large-insert genomic clones represent a powerful tool of the genome analysis. Their utilization provides coordination of data on molecular organization of nucleic acids with cytogenetic data on the chromosome structure. These libraries played an important role in sequencing of genomes of human, mouse, and other organisms as an instrument linking molecular biological and cytogenetic data via construction of contigs and their localization on the chromosomes. They also enabled analysis of orthology between the mammalian genomes. The existing avian libraries fit molecular cytogenetic analysis of the class Aves genome, and can be successfully used for the isolation and characterization of large genomic fragments. This provides utilization of these libraries not only for the chromosome mapping, but also for positional cloning and search for candidate genes for quantitative traits.__________Translated from Genetika, Vol. 41, No. 5, 2005, pp. 581–589.Original Russian Text Copyright © 2005 by Sazanov, Romanov, Smirnov. 相似文献
119.
Yu. L. Bakshaev A. V. Bartov P. I. Blinov S. A. Dan’ko Yu. G. Kalinin A. S. Kingsep I. V. Kovalenko A. I. Lobanov V. I. Mizhiritskii V. P. Smirnov A. S. Chernenko K. V. Chukbar 《Plasma Physics Reports》2004,30(4):318-329
Results are presented from experimental studies of promising output units for high-current pulsed generators within the framework of the program on inertial confinement fusion research with the use of fast Z-pinches. The experiments were carried out on the S-300 facility (4 MA, 70 ns, 0.15 Ω). Specifically, sharpening systems similar to plasma flow switches but operating in a nanosecond range were investigated. Switching rates to a load as high as 2.5 MA per 2.5 ns, stable switching of a 750-kA current to a low-size Z-pinch, and the radiative temperature of the load cavity wall of up to 50 eV were achieved. 相似文献
120.
Alexander Kudryavtsev Susan Brown Alexey Smirnov 《European journal of protistology》2004,40(4):283-287
A strain of Cochliopodium isolated from grassland soil at Sourhope Research Station (Scotland, UK) was found to be identical to the strain “Cochliopodium sp.2” studied by Bark in 1973. We name it Cochliopodium barki. It belongs to a group of species (comprising also C. minus and Cochliopodium sp. “NYS strain”) with very similar scale pattern. 相似文献