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121.
Neuronal organization of the fields Pmm, Pml2, Pe and epm of the periamygdaloid cortex of the cat brain has been studied by means of Golgi and Nissl methods. The field Pmm essentially differs from other fields of this cortex by primitiveness of its cytoarchitectonic an neuronal organization (two layers uniform by the composition of their neurons are distinguished, the structure of the latter is relatively primitive). In the medial part of this field long axonal rarely branching short dendritic, and in the lateral part--poorly differentiating pyramidal and spindle-like cells predominate. The field Pmm can be considered as a transitional formation between the subcortex (the medial nucleus of the amygdaloid body) and other fields of the periamygdaloid cortex. The fields Pml2, Pe and epm are built more complexly: the cells are organized in 4 layers, more complexly differentiated by their form and size than in the field Pmm and correspondingly more various (long axonal densely branching cells are observed: pyramidal and spindle-like--of the cortical type and bushy--of the subcortical type, as well as long axonal rarely branching reticular cells). The short axonal cells in the fields Pml2, Pe and epm are rather variable in their form, size and direction of axons; in the field Pmm they are less numerous. The field Pmm and the complex of the fields Pml2, Pe and epm are perhaps different in their function, this is evident from different projection of their neurons. Axons of the cells in the field Pmm get into less differentiated and the most ancient medial nucleus of the amygdaloid body and into the ancient system of connections of the latter--terminal strip, and neurons of the fields Pml2, Pe and epm are projected into the basolateral part of the amygdaloid body and into the external capsule--phylogenetically younger structures. Besides, poverty of the axonal collateralies in the long axonal neurons and a small amount and uniformity of the forms of the short axonal cells in the field Pmm and contrary, rich collateralies and variety of short axonal cells in the composition of other fields demonstrate more complex internal integrative function, performing in that composition.  相似文献   
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1. We investigated the effects of riparian plant diversity (species number and identity) and temperature on microbially mediated leaf decomposition by assessing fungal biodiversity, fungal reproduction and leaf mass loss. 2. Leaves of five riparian plant species were first immersed in a stream to allow microbial colonisation and were then exposed, alone or in all possible combinations, at 16 or 24 °C in laboratory microcosms. 3. Fungal biodiversity was reduced by temperature but was not affected by litter diversity. Temperature altered fungal community composition with species of warmer climate, such as Lunulospora curvula, becoming dominant. 4. Fungal reproduction was affected by litter diversity, but not by temperature. Fungal reproduction in leaf mixtures did not differ or was lower than that expected from the weighted sum of fungal sporulation on individual leaf species. At the higher temperature, the negative effect of litter diversity on fungal reproduction decreased with the number of leaf species. 5. Leaf mass loss was affected by the identity of leaf mixtures (i.e. litter quality), but not by leaf species number. This was mainly explained by the negative correlation between leaf decomposition and initial lignin concentration of leaves. 6. At 24 °C, the negative effects of lignin on microbially mediated leaf decomposition diminished, suggesting that higher temperatures may weaken the effects of litter quality on plant litter decomposition in streams. 7. The reduction in the negative effects of lignin at the higher temperature resulted in an increased microbially mediated litter decomposition, which may favour invertebrate‐mediated litter decomposition leading to a depletion of litter stocks in streams.  相似文献   
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Rhipicephalus sanguineus Latreille (1806) (Ixodida: Ixodidae) is considered to be the most widely distributed tick and to have a vast range of habitats and hosts, including livestock, pets and wildlife. In addition to morphological differences, recent investigations using approaches based on molecular genetic markers have revealed the existence of different R. sanguineus lineages in different geographic regions. In this study, 475 ticks collected from dogs in the western Iberian peninsula were studied both morphologically and genetically, using 12S and 16S rDNA and COI gene markers in order to clarify the controversy over the systematic status of R. sanguineus sensu lato in Western Europe, and to compare the present data with those sourced from studies conducted in other regions of the world. Despite the high morphometric variability, particularly on spiracles in both genders and in female genitalia, data obtained with different genetic molecular markers show very low variability, suggesting the existence of a unique species. In addition, the phylogenetic analysis showed genetic uniformity, supporting the existence of a well‐defined clade consisting of R. sanguineus s.l. specimens from Western Europe that are distinct from R. sanguineus s.l. from Africa. Furthermore, these data corroborate the existence of a polymorphic species in Western Europe, which requires to be consensually redescribed in view of its medical and veterinary importance in pathogen transmission.  相似文献   
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The methods for preparation and regeneration of protoplasts were tested with respect to the strains of F. coccineum markedly differing in their capacity for antibiotic production, sporulation and the growth rate. It was found that the substrate used for the culture growth had a significant effect on the cell wall and sensitivity of the mycelium to lytic enzymes. An enzyme from Hellix pomatia and its combination with lysozyme were used for lysing the culture. The cytological investigation of the time course of the culture lysis revealed a stage-by-stage pattern of protoplast formation by means of fragmentation of the hyphal contents till a ball was formed. Two to 4 protoplasts differing in their size and structure were formed within a cell. The pH value and osmotically stabilizing component had some effect on the rate of protoplast formation. Highly productive strains were characterized by formation of protoplasts heterogenous in their size and by decreased frequency of regenerations. The enzyme-free protoplasts preserved their viability and capacity for germination in osmotically stabilizing media for 72-96 hours of storage at 4 degrees C. On solid media the regeneration frequency reached 38 per cent. The regenerated cells formed colonies morphologically similar to those of the intact culture.  相似文献   
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Background  

The omics fields promise to revolutionize our understanding of biology and biomedicine. However, their potential is compromised by the challenge to analyze the huge datasets produced. Analysis of omics data is plagued by the curse of dimensionality, resulting in imprecise estimates of model parameters and performance. Moreover, the integration of omics data with other data sources is difficult to shoehorn into classical statistical models. This has resulted in ad hoc approaches to address specific problems.  相似文献   
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