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1.
In this paper the recent population changes of the Wild Boar in different European countries is analysed through the study of hunting statistics. A simultaneous increase in numbers is observed throughout the whole area during the period 1965–1975. From 1975 onwards the population stabilizes itself apart from in peripheral areas like Finland. Potentially favourable factors which play a part in this process are discussed and certain reproductive and dispersive characteristics which favour its invasive behaviour are discussed.  相似文献   
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Marinesco bodies were discovered in substantia nigra neurons of human brain in 1902. The relationships between these intranuclear inclusions and the other structures of the cellular nucleus are still obscure. The aim of this study is to elucidate the morphological and cytochemical peculiarities of intranuclear ubiquitin-immunopositive bodies in the substantia nigra neurons of human brain and to evaluate the interconnections of these peculiarities with nucleolus by means of light microscopy, immunocytochemistry, and confocal laser microscopy. It is found that up to 20% of neurons in substantia nigra of human brain contain ubiquitin-immunopositive Marinesco bodies. These rounded structures are 1–8 μm—more often 2–4 μm—in diameter. Only one-third of them are tightly adjacent to the nucleolus. By a method of silver impregnation of argentophilic proteins associated with nucleolar organizer, the absence was shown of argentophilic proteins, which are characteristic for the nucleolus, in Marinesco bodies. Special ubiquitin-positive substantially smaller structures (less than 1 μm) are revealed in the neurons’ nuclei along with Marinesco bodies. These structures are probably the initial forms in the formation of Marinesco bodies. The existence of two types of ubiquitin-immunopositive intranuclear bodies is revealed by means of confocal microscopy: one has high intensity of immunofluorescence, and the other has low intensity. Heterogeneous distribution of immunopositive product is characteristic of the former. The presence of DNA in Marinesco bodies is detected by using SYTOX Green fluorescent dye. The absence of peripheral heterochromatin zone and weak susceptibility to toluidine blue together with the presence of DNA and the absence of argentophilic proteins suggests substantial structural and chemical differences between Marinesco bodies and nucleoli, which argues against the idea that the detected bodies are modified nucleoli.  相似文献   
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Choline acetyltransferase (ChAT) is the key enzyme for acetylcholine (ACh) synthesis and constitutes a reliable marker for the integrity of cholinergic neurons. Cortical ChAT activity is decreased in the brain of patients suffering from Alzheimer's and Parkinson's diseases. The standard method used to measure the activity of ChAT enzyme relies on a very sensitive radiometric assay, but can only be performed on post‐mortem tissue samples. Here, we demonstrate the possibility to monitor ACh synthesis in rat brain homogenates in real time using NMR spectroscopy. First, the experimental conditions of the radiometric assay were carefully adjusted to produce maximum ACh levels. This was important for translating the assay to NMR, which has a low intrinsic sensitivity. We then used 15N‐choline and a pulse sequence designed to filter proton polarization by nitrogen coupling before 1H‐NMR detection. ACh signal was resolved from choline signal and therefore it was possible to monitor ChAT‐mediated ACh synthesis selectively over time. We propose that the present approach using a labeled precursor to monitor the enzymatic synthesis of ACh in rat brain homogenates through real‐time NMR represents a useful tool to detect neurotransmitter synthesis. This method may be adapted to assess the state of the cholinergic system in the brain in vivo in a non‐invasive manner using NMR spectroscopic techniques.  相似文献   
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In Huntington's disease (HD), the mutant huntingtin protein is ubiquitously expressed. The disease was considered to be limited to the basal ganglia, but recent studies have suggested a more widespread pathology involving hypothalamic dysfunction. Here we tested the hypothesis that expression of mutant huntingtin in the hypothalamus causes metabolic abnormalities. First, we showed that bacterial artificial chromosome-mediated transgenic HD (BACHD) mice developed impaired glucose metabolism and pronounced insulin and leptin resistance. Selective hypothalamic expression of a short fragment of mutant huntingtin using adeno-associated viral vectors was sufficient to recapitulate these metabolic disturbances. Finally, selective hypothalamic inactivation of the mutant gene prevented the development of the metabolic phenotype in BACHD mice. Our findings establish a causal link between mutant huntingtin expression in the hypothalamus and metabolic dysfunction, and indicate that metabolic parameters are powerful readouts to assess therapies aimed at correcting dysfunction in HD by silencing huntingtin expression in the brain.  相似文献   
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An analytical review of recent publications of home and foreign authors on the problem of laboratory diagnosis of campylobacteriosis is presented. The commercial nutrient media, methods of creation of the microaerophilic conditions for cultivation of campylobacter are presented. The filtration method is preferable for isolation of these agents from the studied material highly contaminated by accompanying microflora. A special attention is paid to immunodiagnosis of campylobacteriosis: agglutination reaction, coagglutination reaction, passive hemagglutination reaction, immunoenzyme and radioimmune analyses. Seroepidemiological examination of the staff at one of meat-packing factories in the Republic carried out by the method of indirect immunoenzyme analysis has revealed high levels of anticampylobacteriosis antibodies in 17.9% of examinees. The promising trends in perfection of the methods for laboratory diagnosis of campylobacteriosis are outlined.  相似文献   
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Huntington disease (HD) is a fatal neurodegenerative disorder caused by an expanded CAG repeat in the huntingtin gene. Non-motor symptoms and signs such as psychiatric disturbances, sleep problems and metabolic dysfunction are part of the disease manifestation. These aspects may relate to changes in the hypothalamus, an area of the brain involved in the regulation of emotion, sleep and metabolism. Neuropathological and imaging studies using both voxel-based morphometry (VBM) of magnetic resonance imaging (MRI) as well as positron emission tomography (PET) have demonstrated pathological changes in the hypothalamic region during early stages in symptomatic HD. In this investigation, we aimed to establish a robust method for measurements of the hypothalamic volume in MRI in order to determine whether the hypothalamic dysfunction in HD is associated with the volume of this region. Using T1-weighted imaging, we describe a reproducible delineation procedure to estimate the hypothalamic volume which was based on the same landmarks used in histologically processed postmortem hypothalamic tissue. Participants included 36 prodromal HD (pre-HD), 33 symptomatic HD (symp-HD) and 33 control participants who underwent MRI scanning at baseline and 18 months follow-up as part of the IMAGE-HD study. We found no evidence of cross-sectional or longitudinal changes between groups in hypothalamic volume. Our results suggest that hypothalamic pathology in HD is not associated with volume changes.  相似文献   
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Radially arranged cortical microtubules are a prominent feature of guard cells. We observed guard cells expressing GFP-tubulin (GFP-TUA6) with confocal microscopy and found recognizable changes in the appearance of microtubules when stomata open or close (Eisinger et al., 2012). In the present study, analysis of fluorescence distribution showed a dramatic increase in peak intensities of microtubule bundles within guard cells as stomata open. This increase was correlated with an increase in the total fluorescence that could be attributed to polymerized tubulin. Adjacent pavement cells did not show similar changes in peak intensities or integrated fluorescence when stomatal apertures changed. Imaging of RFP-tagged end binding protein 1 (EB1) and YFP-tagged α-tubulin expressed in the same cell revealed that the number of microtubules with growing ends remained constant, although the total amount of polymerized tubulin was higher in open than in closed guard cells. Taken together, these results indicate that the changes in microtubule array organization that are correlated with and required for normal guard cell function are characterized by changes in microtubule clustering or bundling.  相似文献   
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