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The main aim of the research is to evaluate the applicability of craniometric methods to living animals as well as to define the range of values derived from measuring the heads of brachycephalic types of dogs and their calculated indices. Investigations were conducted on 78 dogs, both male and female, of different age, that belonged to six different breeds: Pekingese, Small Brabant, Griffon Bruxellois, French Bulldog, Pug and English Bulldog (tab.1). A zoometric divider was used to carry out the measurements. On the basis of methods used in craniometry proper, points were established on the heads of the living dogs. Among the craniometric measures were: skull length (AP); cranial length (NA); viscerocranial length (NP) and maximum zygomatic width (ZyZy). The following indices: skull index, length-length index-2, facial index and length-width index-2 were calculated on the basis of the obtained data. The skull index was treated as a basis for evaluating the morphotype while the other indices served as additional tools. The results confirm that the measurements carried out on living animals are adequate to their equivalents in craniometry. The skull index for brachycephalic dogs was calculated and was found to be between 80-100.
The aim of the study was to describe the shape of the articular facets of the axis in dogs of three morphotypes and different body weights. The facet joints contribute significantly to the stability of the cervical spine, predominantly by providing axial rotational stability at C₂ and C₃. The research involved the examination of cadavers of 30 adult male and female dogs of three morphotypes and body weights from 2.22 to 72 kg. The craniocervical junction elements, especially the second cervical vertebra (axis), were isolated by standard anatomical preparation. The maximal articular surface width ASW, the maximal articular surface length - ASL and the inclination of the articular surface - h were measured. The articular surface length-to-width index was calculated. The linear correlation function for K and h with body mass and the cranial index and the coefficient of determination R² were determined. The atlantoaxial dorsal ligament was put to the microscopic test. Index K ranged from 0.71 to 1.90. In small breeds, more longitudal oval-shaped facets were observed. Circular facets and more transversely oval-shaped facets were found in medium and large breeds. The large breeds have a preventive mechanism against greater mobility in C₂-C₃. Their atlantoaxiale dorsale ligament is fibrocartilagineus. These dogs are consequently less exposed to damages of the intervertebral disc and medulla spinalis.
The paper describes the different types of cell death during the process of wood cell formation and terminological variety found in the literature concerned. The cell death referred to as programmed cell death (PCD), is genetically controlled and fundamental for the correct function of the whole organism of woody plants. The wood is mainly composed of the tracheary elements fulfil as conductors of water, fibers that provide the mechanical support and parenchyma cells playing an important role in the storage of water and reserve materials. The PCD of these elements constitutes the final stage of their differentiation and it is proceeded by: (i) cambial cell divisions, (ii) the enlargement of the cambial derivatives. The successive phase concerns (iii) deposition of secondary cell walls and its lignification. After that, the cell commences to digest protoplast, what means that each cell participates in the process of its own demise actively. However, the time and the sequence of the appearance of these phases are distinct among the woody cells. In the case of the tracheary elements the digestion of the protoplast occurs immediately after the tonoplast breakdown. Therefore, these cells are short−lived elements of wood. The life span of the fibers and the parenchyma cells is longer (from month for fibers and years in case of parenchyma cells). For the latter cells the positional information (distance from the cambium) and vicinity with short−lived tracheary elements are considered to be important for undergoing the process of death
The effects of tree genotype on below−ground ectomycorrhizal fungal communities of 40 years old European larch from Kowary, Bliżyn, Świętokrzyski National Park and Szczytna Śląska origins was investigated. The research was carried out in the provenance trial in the Experimental Forestry Unit in Krynica Zdrój (Beskid Sądecki Mountains, S Poland). Ectomycorrhizal fungal communities were assessed by a combination of morphological and molecular techniques. In total 22 fungal taxa has been distinguished (from 17 to 20, depending on larch provenance). Thirteen ectomycorrhizal fungal taxa were common to all analysed origins. The mean taxa richness, Shannon diversity and Simpson dominance coefficient did not differ significantly between provenances. Based on fungal taxa composition (Jaccard coefficient) tested larch origins were characterized by a high level of similarity of ectomycorrhizal fungal communities. Six detected fungal taxa have not been previously reported as symbiotic partners of European larch.
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