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1.
Trofimov  I. A.  Trofimova  L. S.  Yakovleva  E. P.  Oparina  O. S.  Oparin  M. L. 《Biology Bulletin》2019,46(10):1442-1447
Biology Bulletin - V.V. Dokuchaev’s ideas are the foundation of modern ideas about rational nature-usage methods in our steppes in order to ensure productive longevity of agro-ecosystems and...  相似文献   
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The review considers the structure, evolution, and possible mechanisms of spreading of intrachromosomal and interchromosomal segment duplications (SD), which account for more than 5% of the human genome. Most SD are mosaic and consist of multiple modules, which occur in several copies in different genome regions. SD are preferentially located in pericentric and subtelomeric regions, which are least studied on the human chromosomes. Homologous recombination between SD results in various chromosome rearrangements, contributing to the genome instability and the origin of several human hereditary disorders.  相似文献   
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Female CBA mice were injected with s.c. synthetic tetrapeptide Epithalon from a 6-month age until death. The drug failed to affect the body weight or food consumption, physical activity or behavioural parameters. However, it slowed down the age-related switching off of the estrus function, decreased body temperature, decelerated free redical processes, prolonged the mice life span with an accompanying drop in spontaneous tumour incidence.  相似文献   
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Abstract.  1. Molecular techniques have greatly added to the number of known sympatric cryptic species in insects. Ecological differences between these newly distinguished species are little explored, but niches often appear to overlap strongly. These cases are good models for exploring new ideas about species coexistence and community structure.
2.  Acanthoscelides obtectus and A. obvelatus are two sister species of bean bruchids, which have been confused until the last decade. One important ecological difference between them has emerged, however: A. obtectus is multivoltine and now distributed worldwide, whereas A. obvelatus is univoltine and restricted to Mesoamerica. Where their ranges overlap, the two species share the same host plants and larvae can sometimes complete development in the same seed.
3. The analysis of 27 622 Mexican individuals of the two species in 2001-2002 and 2002-2003 indicates that their niches overlap, but are differentiated with respect to altitude and the kind of beans (wild vs. domesticated). The principal patterns in their relative abundance in different habitats, and at different seasons, were constant from one year to the next.
4. As sympatry of these species seems to be of recent origin, the observed niche differentiation may not have evolved in response to competition, but could instead be the consequence of physiological differences, evolved independently in each species in allopatry, that pre-adapted them for different altitudes and kinds of resources.
5. The combination of biological and historical factors thus appears to allow these two sibling species to coexist in sympatry, despite their broadly overlapping ecological niches.  相似文献   
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Modern proteomic techniques make it possible to identify numerous changes in protein expression in tumors as compared to normal tissues. Although proteomics is currently widely used, identification of proteins differentially expressed in particular types of cancer remains a challenging task. The goal of our study was to detect novel protein markers of colorectal cancer using comparative proteomics of protein extracts obtained from primary tumors and adjacent normal tissues. Coloreetal cancer is nearly asymptomatic at the early stages, which calls for development of fast and sensitive methods for molecular diagnostics. Proteomes of 11 paired specimens of primary colorectal tumors and adjacent histologically normal tissues were studied using comparative 2D PAGE. Altogether, 16 proteins with altered expression levels were detected, including 13 proteins with increased levels and three proteins with decreased levels in tumor tissues. These proteins were identified using MALDI-TOF mass spectrometry. The proteins GPD1, RRBP1 (increased levels), HNRNPH1, and SERPINB6 (decreased levels) have been associated with colorectal cancer for the first time.  相似文献   
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This paper examines the influence of the location of settlements, railroads, and highways on the spatial structure of the Otis tarda population in the Trans-Volga region that was studied in the years 1998–2016 in a model area of 12000 km2 that is located in the southern part of the Saratov Trans-Volga region. The zone of the impact made by our estimated disturbance factor due to the movement of people and a variety of ground vehicles along various-purpose roads on the territorial distribution of bustards in autumn can be denoted as a 300–500 m width band on both sides of the transport communications. Shelterbelts that were created along transport communications render a beneficial effect on the distribution of O. tarda and reduce the influence of the disturbance factor. Furthermore, crop rotation fields with side sizes of more than 1 km can be considered a factor that compensates for the anxiety of birds. We have found that in the Saratov Trans-Volga region, because of the large size of crop rotation fields and significant development of roadside and shelter belts, no special measures are required to protect O. tarda such as restrictions on the movement of people and vehicles over the territory where this species lives.  相似文献   
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<正> As scientific collaborators of the Chinese-American joint project "Neogene Rocks and Faunas, Yushe Basin, Shanxi, PRC", the present authors, with William R. Downs, Northern Arizona University, sampled the Yushe microfauna in the fall of 1987 and 1988. The fossil temains were retrieved by surface collection and by wet-sieving bulk quantities of sediment.  相似文献   
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A scheme for automatic impulse foam breaking during biosynthesis of cephalosporin C in 0.63 m3 pilot plant fermenters was developed and tested. It was shown that the use of an aerodynamic foam breaker did not limit the antibiotic biosynthesis by oxygen and promoted stabilization of the foam level in the apparatus without chemical antifoamers and increased air supply.  相似文献   
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