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171.
Zinchenko R. A. Zinchenko S. P. Galkina V. A. Elchinova G. I. Nurbaev S. D. Polyakov A. V. Nekrasova N. Yu. Ginter E. K. 《Russian Journal of Genetics》2003,39(9):1076-1084
Summarized genetic epidemiological characteristics of nonsyndromic sensorineural deafness in six raions of Chuvash Republic (Cheboksary, Kanash, Morgaushi, Tsivil'sk, Mariinski Posad, and Alatyr') are presented. A total of 264419 individuals were examined. Forty-five families (60 affected individuals) with autosomal recessive (AR) and 8 families (18 affected individuals) with autosomal dominant (AD) nonsyndromic sensorineural deafness (NSSD) were identified. The load of AD and AR NSSD in the raions examined was estimated. A correlation between the distribution of AR NSSD and genetic drift was demonstrated. Furthermore, the load of AR NSSD was substantially higher in the regions with higher differentiation level. The Spearman's correlation coefficient value was 0.87. Typing of the 35delG mutation in the gene for connexion 26 was carried out in 34 patients from 26 families with AR NSSD. Comparative estimates of the NSSD prevalence in a number of Russian populations were performed. 相似文献
172.
173.
We have shown that human neutrophils develop dynamic thin and very long tubulovesicular extensions (cytonemes) upon adhesion to fibronectin, if cell spreading was blocked by Na(+)-free medium or by 4-bromophenacyl bromide, N-ethylmaleimide, 7-chloro-4-nitrobenz-2-oxa-1,3-diazole and cytochalasin D (S. I. Galkina, G. F. Sud'ina and V. Ullrich, (2001). Exp. Cell Res. 266, 222-228). In the present work we found that similar in size and behavior tubulovesicular extensions were formed on the neutrophil cell bodies upon adhesion to fibronectin-coated substrata in the presence of the nitric oxide donor diethylamine NONOate. In the presence of the nitric oxide synthase inhibitor N-omega-nitro-L-arginine methyl ester, neutrophils were well spread and had no microextensions. Using scanning electron microscopy, we demonstrated that tubulovesicular extensions of neutrophils executed long-range adhesion and binding objects for phagocytosis, such as serum-opsonized zymosan particles and erythrocytes. Tubulovesicular extensions anchored neutrophils to substrata in a beta1 and beta2 integrin-independent, but L-selectin-dependent manner. BODIPY-sphingomyelin impaired development of tubulovesicular extension, and heparitinase 1 played a role in their destruction. Membrane tubulovesicular extensions are supposed to represent protrusions of an intracellular exocytotic traffic and serve as cellular sensory and adhesive organelles. Nitric oxide seems to play a role in regulation of tubulovesicular extensions formation, thus affecting neutrophil adhesive interactions and phagocytosis. 相似文献
174.
Tallury SP Hilu KW Milla SR Friend SA Alsaghir M Stalker HT Quandt D 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2005,111(7):1229-1237
Section Arachis is the largest of nine sections in the genus Arachis and includes domesticated peanut, A. hypogaea L. Most species are diploids (x=10) with two tetraploids and a few aneuploids. Three genome types have been recognized in this section (A, B and D), but
the genomes are not well characterized and relationships of several newly described species are uncertain. To clarify genomic
relationships in section Arachis, cytogenetic information and molecular data from amplified fragment length polymorphism (AFLP) and the trnT-F plastid region were used to provide an additional insight into genome composition and species relationships. Cytogenetic
information supports earlier observations on genome types of A. cruziana, A. herzogii, A. kempff-mercadoi and A. kuhlmannii but was inconclusive about the genome composition of A. benensis, A. hoehnei, A. ipaensis, A. palustris, A. praecox and A. williamsii. An AFLP dendrogram resolved species into four major clusters and showed A. hypogaea grouping closely with A. ipaensis and A. williamsii. Sequence data of the trnT-F region provided genome-specific information and showed for the first time that the B and D genomes are more closely related
to each other than to the A genome. Integration of information from cytogenetics and biparentally and maternally inherited
genomic regions show promise in understanding genome types and relationships in Arachis. 相似文献
175.
176.
Volynskiĭ KE Volkova TM Galkina TG Krasnoperov VG Pluzhnikov KA Khvoshchev MV Grishin EV 《Bioorganicheskaia khimiia》1999,25(1):25-30
A fragment of the structural gene of alpha-latrocrustotoxin, a new representative of latrotoxins from black widow spider venom, was cloned. The fragment (1191 bp) was obtained by means of PCR based on the data obtained by sequencing tryptic peptides of the toxin. The fragment codes for a 397-aa sequence. The encoded polypeptide is the C-terminal fragment of the toxin central domain that presumably contains a site responsible for the toxin species specificity. The structural similarity of this fragment to the corresponding fragments of other latrotoxins was studied. 相似文献
177.
178.
Biased mutations and microsatellite variation 总被引:10,自引:6,他引:4
Mutation bias is one of the forces that may constrain the variation at
microsatellite loci. Here, we study the dynamics of population statistics
and the genetic distance between two populations under multiple stepwise
mutations with linear bias and random drift. Expressions are derived for
these statistics as functions of time, as well as at mutation-drift
equilibrium. Applying these expressions to published data on humans and
chimpanzees, the regression coefficient of mutation bias on allele size was
estimated to be at least between - 0.0064 and -0.013. The assumption of
mutational bias produces larger estimates of divergence times than are
obtained in its absence; in particular, the time of split between African
and non-African human populations is estimated to be between 183,000 and
222,000 years, assuming one-step mutations and no selection. With multistep
mutations, the divergence time is estimated to be lower.
相似文献
179.
Taxonomy lies at the heart of species conservation, yet many large New Zealand orthopterans remain undescribed. Among New Zealand’s anostostomatid wētā, Hemiandrus (ground wētā) is the most speciose genus but also the most poorly characterised and thus most in need of taxonomic and ecological work. Here we redescribe H. maculifrons and describe two new species of ground wētā previously encompassed by the specific name Hemiandrus maculifrons: Hemiandrus luna sp. nov. and H. brucei sp. nov. We also describe a morphologically similar and related species, Hemiandrus nox sp. nov.
http://zoobank.org/urn:lsid:zoobank.org:pub:71EA0879-A2F9-46B2-A105-E97A9AB25061
http://zoobank.org/References/71EA0879-A2F9-46B2-A105-E97A9AB25061 相似文献
180.
Benthic insects in Swedish lake-outlet streams: patterns in species richness and assemblage structure 总被引:3,自引:0,他引:3
1. We studied how species richness of three hierarchical insect species groups, namely all benthic, lotic and filtering taxa, were related to a number of environmental variables in a data set from fifteen Swedish lake outlets. 2. In partial least-squares analyses, we found that size-related factors (stream width, discharge) and velocity-related factors (current velocity, substratum particle size) were positively associated, and productivity-related factors (chlorophyll a, seston energy, conductivity) negatively associated, with the species richness of the three groups. 3. The weak and negative relationship of richness with productivity largely negated theoretical predictions, whereas the species-environment results corroborated earlier findings from running water systems. 4. The most important factors associated with the species composition of the lake outlets studied included pH, lake area, discharge, channel width and detritus. 5. Of the filter feeders, most species of blackflies (Diptera: Simuliidae) showed a negative relationship with pH. 6. A nested subset analysis demonstrated that species-poor sites did not have a subset of species found at more species-rich sites in any of the three hierarchical groups. 相似文献