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Badania przeprowadzono w rezerwacie przyrody „Bagno Serebryskie” koło Chełma, w którym w latach 2008–2009 kompleks odłogów o areale 1 ha poddano restytucji przyrodniczej z wykorzystaniem metody pełnej uprawy i wysiewem nasion kilkudziesięciu gatunków, które wcześniej zebrano na pobliskich łąkach donorowych. Zabiegi uprawowe wykonano w równoległe pasy o szerokości ok. 8 m, rozdzielone pasami o glebie nieuprawionej o tej samej szerokości. Siew wykonano także w pasy, lecz ustawione do nich prostopadle. W ten sposób otrzymano ponad sto kwadratowych poletek o boku 8 m, reprezentujących cztery warianty: 1 – uprawione obsiane, 2 – nieuprawione obsiane, 3 – uprawione nieobsiane i 4 – nieuprawione nieobsiane. W 2010 roku na poletkach doświadczalnych wykonano zdjęcia fitosocjologiczne: oceniono pokrycie warstwy mszystej i zielnej oraz obfitość występowania wysianych roślin. Stwierdzono, że w restytucji przyrodniczej odłogów, metoda pełnej uprawy sprzyja osiedlaniu się roślin łąkowych z wysianych nasion. Siew nasion spowodował istotny wzrost obfitości występowania gatunków pożądanych w restytucji przyrodniczej.
The diversity and abundance of bumblebees (Bombus Latr.) in eight parks of Warsaw city and the impact of park size (range from 1.9 to 73 ha) as well as other selected characteristics (the percentage of the area covered by tree and the quality of park surroundings) on the bumblebee community were evaluated. In each park, bumblebees were observed along designated paths for 30 minutes. In total, 12 species of bumblebees were recorded, of which four belonged to cuckoo bumblebees (Psithyrus subgenus). We found: B. terrestris (L.), B. lapidarius, (L.), B. pascuorum (Scop.), B. hortorum (L.), B. semenoviellus (Skorikov), B. hypnorum (L.), B. ruderarius (Müller), B. pratorum (L.) and four cuckoo bumblebee species: B. (Ps.) bohemicus (Seidl.), B. (Ps.) campestris (Pz.), B. (Ps.) rupestris (F.), B. (Ps.) vestalis (Fourc.). The size of parks, percentage of area covered by trees, and characteristics of the areas surrounding the parks were found to be not significant for the diversity and abundance of bumblebees in urban parks. However, our results indicate the importance of the semi-natural areas within the parks for the species diversity.
The aim of the study was to determine the nucleotide sequence of the CYP21 gene of the Eurasian lynx, eight representatives of five selected domestic cat breeds and a European mixed-breed cat on account of the key role of this gene product in adrenal steroidogenesis. Cats nuclear DNA was obtained from peripheral blood, while the lynx DNA was isolated from muscle tissue. 21HS gene amplification was performed in 10 parts with the unified PCR conditions. The reaction products were sequenced. On the basis of the determined nucleotide (nc) sequence of the gene, the sequence of amino acids (aa) of the protein was determined. The sequences obtained in our study and collected from the GeneBank were aligned using Mafft and subjected to phylogenetic analysis using the program MrBayes 3.2. A total of 11 SNP’s were detected in 9 tested cat breeds and an additional 3 indels in the mixed-breed cat. Between the studied cats and lynx a total of 33 SNP differences were determined. In addition, three indels were located in the lynx that were absent in cats. In domestic cats the 21HS gene occurs as a series of three long alleles: 2500 bp, 2503 bp, and 2504 bp. Both alleles of lynx were 2502 bp in length. Genetic distance was identified between the studied breeds of cats, as well as between cats and the lynx. A genetic analysis of Cyp21 nucleotide sequences of cats and lynx was performed against homologous sequences obtained from GeneBank, derived from 13 different vertebrate species. In addition, evolutionary distance was estimated between the amino acid sequences (aa) of the cat/lynx and homologous sequences obtained from the GeneBank and derived from 15 different vertebrate species. It was demonstrated that the aa sequence of cat is almost identical to the sequence of lynx. Overall, basing on 21HS aa sequence, the closest kinship links felines and canids, then felines with pigs and ruminants, after which were rodents. The lowest CYP21 kinship links aa sequences of felines with eels and birds, followed by humans and apes.
The aim of this study was to determine the nucleotide sequence of the CYP21 gene in the wolf and representatives of five breeds of dogs (selected according to a classification by Parker et al, 2004) in connection with the key role of the product of this gene in the genesis of many diseases in dogs. Nuclear DNA of dogs was obtained from peripheral blood, and the wolf’s DNA was isolated from muscle tissue. The amplification of the 21HS gene was carried out in 10 fragments under standardized PCR conditions. The reaction products were sequenced. The sequence of amino acids in the protein was determined on the basis of the nucleotide sequence. The sequences obtained in our study and those retrieved from the GeneBank database were compared with the Mafft program (15) and subjected to phylogenetic analysis with the MrBayes 3.2 program (35). We detected a total of nine SNP mutations in introns and exons. Furthermore, a deletion of two nucleotides, that differentiates the breeds, was detected in the promoter region. Only two differences between the dogs and the wolf were found in SNP: one in an exon and one in an intron. Genetic distance was determined between the selected breeds of dogs and between the wolf and the dogs of each breed. In addition, we estimated the evolutionary distances between amino acid sequences of the dog/wolf and homologous 21HS sequences of eight different vertebrate species obtained from GeneBank. It was shown that, among mammals, the amino acid sequence of the dog/wolf is the most similar to the sequence of the pig, and the least similar to that of the human. The sequences determined in this study may provide a reference point for the research on the CYP21 gene structure and expression in various tissues of dogs for therapeutic purposes.
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