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11.
α-Amylase isozymes were detected via electrophoretic separation in a Tris-glycine polyacrylamide gel system (pH 8.4). Three chromosome 6B loci controlling the α-amylase isozyme composition were identified by studying the grain α-amylase patterns in an F→∞ self-pollinating population of winter common wheat (Donskoi Mayak). The loci were found to take the following order in the long arm of chromosome 6B: cen. cen.—α-Amy-B3—α-Amy-B6—α-Amy-B1  相似文献   
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13.
The polymorphism of winter common wheat with respect to β-amylase isoenzymes has been analyzed using electrophoresis in polyacrylamide gel (PAAG) buffered with a Tris-glycine system (pH 8.3). Seven β-amylase isoenzymes have been found in wheat cultivars and the breeding stock. Isoenzymes A, B, and C are the most frequent in Russian and Ukrainian cultivars (51.7 4.7, 30.7 3.8, and 11.9 2.5%, respectively). Two alleles of the β-Amy-D1 locus of the long arm of chromosome 4D have been identified. The substrate-enzyme affine effect can be used to locate the zones of activity of this enzyme by means of staining for proteins. It has been determined that β-amylase zymotypes may play a role in the aggregating capacity of the grain protein complex via the formation of S-S bonds.  相似文献   
14.
INTRODUCTIONAsearlyasin1948wehavefr8CtionatedisolatednucleifromnormalandtumorcellsbyextractionwithiMNaCIanddilutealkali[1].Thenuclearresiduewasthenstudiedmorethoroughly[2,3].Lateron,sillillarproteinousnuclearresidueswereisolatedbyotherworkers[46]andasstud…  相似文献   
15.
Algorithms and software for support of gene identification experiments   总被引:1,自引:0,他引:1  
MOTIVATION: Gene annotation is the final goal of gene prediction algorithms. However, these algorithms frequently make mistakes and therefore the use of gene predictions for sequence annotation is hardly possible. As a result, biologists are forced to conduct time-consuming gene identification experiments by designing appropriate PCR primers to test cDNA libraries or applying RT-PCR, exon trapping/amplification, or other techniques. This process frequently amounts to 'guessing' PCR primers on top of unreliable gene predictions and frequently leads to wasting of experimental efforts. RESULTS: The present paper proposes a simple and reliable algorithm for experimental gene identification which bypasses the unreliable gene prediction step. Studies of the performance of the algorithm on a sample of human genes indicate that an experimental protocol based on the algorithm's predictions achieves an accurate gene identification with relatively few PCR primers. Predictions of PCR primers may be used for exon amplification in preliminary mutation analysis during an attempt to identify a gene responsible for a disease. We propose a simple approach to find a short region from a genomic sequence that with high probability overlaps with some exon of the gene. The algorithm is enhanced to find one or more segments that are probably contained in the translated region of the gene and can be used as PCR primers to select appropriate clones in cDNA libraries by selective amplification. The algorithm is further extended to locate a set of PCR primers that uniformly cover all translated regions and can be used for RT-PCR and further sequencing of (unknown) mRNA.   相似文献   
16.
This paper describes the integrated effect of high summer temperature, intensive insolation, gas pollution, and dust in the air on the pigment content and net oxygen production (apparent photosynthesis) and dark respiration rates of common hibiscus (Hibiscus syriacus L.) leaves. The study included three observation sites: Tashkent Botanical Garden (Academy of Sciences, the Republic of Uzbekistan), the public garden in the central part of the city of Tashkent, and a mountain holiday camp. The research was carried out in 2017 during the period of active vegetation. The results of experiments showed a high adaptive potential of H. syriacus L., as well as its adaptiveness to stress environmental factors of the semiarid zone, provided a sufficient level of its irrigation. The ecological plasticity of the photosynthetic apparatus of hibiscus plays a key role in species adaptation to environmental conditions. It has been revealed that the growth of the plants of the Tashkent Botanical Garden under shading conditions leads to the formation of large, wide, thin, shade leaf blades, which can be considered as the manifestation of sciomorphosis. Heliomorphosis features of hibiscus leaves were identified in mountains, where sun leaves with significantly smaller, thickened, and compacted blades are formed under high insolation. The adaptive significance of these structural leaf modifications is to strengthen photosynthetic capacity for compensating the deficiency in sunlight (in the case of sciomorphosis), and, on the contrary, to provide mutual shading for photosynthetic elements as a measure of protection against the damaging effect of redundant solar radiation (in the case of heliomorphosis). This provides carbon dioxide assimilation and organic matter production for maintaining the constant energy balance for the plant under different environmental conditions. The study of the temperature correlation of dark respiration and net oxygen production rates has shown that these processes are more resistant to temperature injuries under more extreme environmental conditions. In addition, mature H. syriacus leaves have a higher resistance than young leaves; i.e., the plant adapts to possible temperature drops in the process of its ontogenesis. Taking into account the optimal measuring conditions, the net oxygen production rate of H. syriacus during the period of active vegetation is approximately at the same level under different growing conditions (0.20 ± 0.05 μmol of O2/(dm2 s)); this is considered a norm of reaction of the net production (apparent photosynthesis) rate of H. syriacus and determines the specific features of its photosynthetic apparatus.  相似文献   
17.
Mesocoelium lanfrediaesp. nov. (Digenea: Mesocoeliidae) inhabits the small intestine of Rhinella marina (Amphibia: Bufonidae) and is described here, with illustrations provided by light, scanning electron microscopy and molecular approachs. M. lanfrediae sp. nov. presents the typical characteristics of the genus, but is morphometrically and morphologically different from the species described previously. The main diagnostic characteristics of M. lanfrediae sp. nov. are (i) seven pairs of regularly-distributed spherical papillae on the oral sucker, (ii) ventral sucker outlined by four pairs of papillae distributed in a uniform pattern and interspersed with numerous spines, which are larger at the posterior margin and (iii) small, rounded tegumentary papillae around the opening of the oral sucker, which are morphologically different from those of the oral sucker itself, some of which are randomly disposed in the ventrolateral tegumentary region of the anterior third of the body. Addionally, based on SSU rDNA, a phylogenetic analysis including Brachycoeliidae and Mesocoeliidae taxa available on GenBank established the close relationship between M. lanfrediae sp. nov. and Mesocoelium sp.  相似文献   
18.
The polymorphism of winter common wheat with respect to β-amylase isoenzymes has been analyzed using electrophoresis in polyacrylamide gel (PAAG) buffered with a Tris-glycine system (pH 8.3). Seven β-amylase isoenzymes have been found in wheat varieties and the breeding stocks. Isoenzymes A, B, and C are the most frequent in Russian and Ukrainian varieties (51.7 ± 4.7, 30.7 ± 3.8, and 11.9 ± 2.5%, respectively). Two alleles of the β-Amy-D1 locus of the long arm of chromosome 4D have been identified. The substrate-enzyme affine effect can be used to locate the zones of activity of this enzyme by means of staining for proteins. It has been determined that β-amylase isoenzymes may play a role in the aggregating capacity of the grain protein complex via the formation of S-S bonds.  相似文献   
19.
Species composition and distribution of macrozoobenthos have been studied in the shallow water zone (0–20 m) of Southern Lake Baikal (Bolshiye Koty Bay). The amount of taxa recorded reached up to 244 species distributed among 16 distinctive communities of complex structure and high species diversity. The Shannon index of specific diversity was found to vary between 2.9 and 4.8 bits. Mosaic spatial distribution of communities is controlled by both biotic and abiotic factors. Trophic zones with respect to the bottom-dwellers are determined by two lithodynamic phenomena: washout and accumulation of thin deposits (fine to medium silt and mud). The bottom with coarse clastic material (pebbles and boulders), where fine sediments are eroded and resuspended, is dominated by immobile and mobile sestonophagous species as well as by the communities dominated by detrito- and phytophagous species. Areas with soft fine sediments are dominated by macro-invertebrates, which ingest the substrate indiscriminately.  相似文献   
20.
Oligochaete fauna of Lake Baikal   总被引:1,自引:1,他引:0  
Oligochaetes are one of the most abundant groups of invertebrates in Lake Baikal. They compose up to 70–90% of the biomass and numbers of zoobenthos and are distributed from the water edge to the maximum depth. There are 207 identified species and subspecies belonging to 44 genera and seven families, of which 160 species and 13 genera are endemic. Many are relict species. The main peculiarities of oligochaete fauna of Lake Baikal are: immiscibility of its ecologically different complexes (Palaearctic and Baikalian), its antiquity and heterogeneity, and intense radiation of the species.  相似文献   
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