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Alterations of the von Hippel–Lindau (VHL) tumor suppressor gene can cause different hereditary tumors associated with VHL syndrome, but the potential role of the VHL gene in papillary thyroid carcinoma (PTC) has not been characterized. This study set out to investigate the relationship of VHL expression level with clinicopathological features of PTC in an ethnically and geographically homogenous group of 264 patients from Serbia, for the first time. Multivariate logistic regression analysis showed a strong correlation between low level of VHL expression and advanced clinical stage (OR = 5.78, 95% CI 3.17–10.53, P<0.0001), classical papillary morphology of the tumor (OR = 2.92, 95% CI 1.33–6.44, P = 0.008) and multifocality (OR = 1.96, 95% CI 1.06–3.62, P = 0.031). In disease-free survival analysis, low VHL expression had marginal significance (P = 0.0502 by the log-rank test) but did not appear to be an independent predictor of the risk for chance of faster recurrence in a proportion hazards model. No somatic mutations or evidence of VHL downregulation via promoter hypermethylation in PTC were found. The results indicate that the decrease of VHL expression associates with tumor progression but the mechanism of downregulation remains to be elucidated.  相似文献   
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Disentangling the contribution of long‐term evolutionary processes and recent anthropogenic impacts to current genetic patterns of wildlife species is key to assessing genetic risks and designing conservation strategies. Here, we used 80 whole nuclear genomes and 96 mitogenomes from populations of the Eurasian lynx covering a range of conservation statuses, climatic zones and subspecies across Eurasia to infer the demographic history, reconstruct genetic patterns, and discuss the influence of long‐term isolation and/or more recent human‐driven changes. Our results show that Eurasian lynx populations shared a common history until 100,000 years ago, when Asian and European populations started to diverge and both entered a period of continuous and widespread decline, with western populations, except Kirov, maintaining lower effective sizes than eastern populations. Population declines and increased isolation in more recent times probably drove the genetic differentiation between geographically and ecologically close westernmost European populations. By contrast, and despite the wide range of habitats covered, populations are quite homogeneous genetically across the Asian range, showing a pattern of isolation by distance and providing little genetic support for the several proposed subspecies. Mitogenomic and nuclear divergences and population declines starting during the Late Pleistocene can be mostly attributed to climatic fluctuations and early human influence, but the widespread and sustained decline since the Holocene is more probably the consequence of anthropogenic impacts which intensified in recent centuries, especially in western Europe. Genetic erosion in isolated European populations and lack of evidence for long‐term isolation argue for the restoration of lost population connectivity.  相似文献   
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Synthesis of 2-epi-fortimicin B has been accomplished by processes involving solvolyses of both 1-N-benzyloxycarbonyl- and 1-N-acetyl-2-O-(methylsulfonyl)fortimicins B, which occur with participation of the carbonyl oxygen atoms of the 1-N-acyl groups. The results illustrate both the greater effectiveness of acetamido groups in neighboring-group participation relative to benzyloxycarbonylamino groups, and the sensitivity of the nature of the products to the reaction conditions.  相似文献   
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The interstitium is the extravascular intertubular space of the renal parenchyma, which provides structural support to the functional renal units and is included at the same time in nearly all renal functions. Alterations to this renal compartment have been found in almost all glomerular diseases. During the last thirty years the studies of a few groups of investigators have shown that the degree of the renal dysfunction is strongly correlated with the changes in the tubulointerstitial compartment. We made a morphometric study of a group of 10 renal biopsies, previously diagnosed as IgA nephropathy or membranoproliferative glomerulonephritis. For morphometric analysis we made colour extraction of the interstitial area on tissue sections stained with trichrom Masson using the LUCIA M-NIKON image analysing system with integrated software for statistical analysis of the data. We measured the surface of the marked fields and the results were expressed as a percentage of the total scanned area. The results were correlated with the serum creatinine at the time of biopsy. We found fibrosis occupying more than 10% of the tubulointerstitial surface in all 10 patients. Six of them had a moderate level of fibrosis, occupying more that 20% of the tubulointerstitial space. The statistical analysis of these results showed a significant correlation between the degree of the interstitial expansion and the serum creatinine. The results showing the correlation between these parameters will enable the quantitative histological analyses to be included in the process of the nephropathological diagnosis in order to evaluate the histological risk factors in glomerular diseases.  相似文献   
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The aim of this work is to discuss the distribution of Oligochaeta (Annelida) in the Danube River using the collections made by the Joint Danube Survey 2007 (JDS2) on more than 2800 km of the river. The basic faunistical features of the oligochaete assemblages were analysed with regard to three main sectors of the Danube (upper, middle and lower reaches, the last with the Danube Delta). A total of 52 oligochaete taxa have been recorded. Most of the observed species are typical of the potamon-type rivers in the region, and are well adapted to moderate-to-high organic load. The highest taxa richness and frequency of occurrence were observed among the Tubificidae family. Naididae, Propappidae, Enchytraeidae and Haplotaxidae had also low frequency. The upper reach of the Danube showed the lowest species richness, while the middle reach is characterised by its highest species richness. Construction of dams and regulation of the riverbed have resulted in an increase of limno(rheo)philic taxa which prefer slow-flowing and lentic zones.  相似文献   
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Manuel Lopes‐Lima  David C. Aldridge  Rafael Araujo  Jakob Bergengren  Yulia Bespalaya  Erika Bódis  Lyubov Burlakova  Dirk Van Damme  Karel Douda  Elsa Froufe  Dilian Georgiev  Clemens Gumpinger  Alexander Karatayev  Ümit Kebapçi  Ian Killeen  Jasna Lajtner  Bjørn M. Larsen  Rosaria Lauceri  Anastasios Legakis  Sabela Lois  Stefan Lundberg  Evelyn Moorkens  Gregory Motte  Karl‐Otto Nagel  Paz Ondina  Adolfo Outeiro  Momir Paunovic  Vincent Prié  Ted von Proschwitz  Nicoletta Riccardi  Mudīte Rudzīte  Māris Rudzītis  Christian Scheder  Mary Seddon  Hülya Şereflişan  Vladica Simić  Svetlana Sokolova  Katharina Stoeckl  Jouni Taskinen  Amílcar Teixeira  Frankie Thielen  Teodora Trichkova  Simone Varandas  Heinrich Vicentini  Katarzyna Zajac  Tadeusz Zajac  Stamatis Zogaris 《Biological reviews of the Cambridge Philosophical Society》2017,92(1):572-607
Freshwater mussels of the Order Unionida provide important ecosystem functions and services, yet many of their populations are in decline. We comprehensively review the status of the 16 currently recognized species in Europe, collating for the first time their life‐history traits, distribution, conservation status, habitat preferences, and main threats in order to suggest future management actions. In northern, central, and eastern Europe, a relatively homogeneous species composition is found in most basins. In southern Europe, despite the lower species richness, spatially restricted species make these basins a high conservation priority. Information on freshwater mussels in Europe is unevenly distributed with considerable differences in data quality and quantity among countries and species. To make conservation more effective in the future, we suggest greater international cooperation using standardized protocols and methods to monitor and manage European freshwater mussel diversity. Such an approach will not only help conserve this vulnerable group but also, through the protection of these important organisms, will offer wider benefits to freshwater ecosystems.  相似文献   
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The European cave bear (Ursus spelaeus), which became extinct around 15,000 years ago, had several morphologically different forms. Most conspicuous of these were small Alpine cave bears found at elevations of 1,600 to 2,800 m. Whereas some paleontologists have considered these bears a distinct form, or even a distinct species, others have disputed this. By a combination of morphological and genetic methods, we have analyzed a population of small cave bears from Ramesch Cave (2,000 m altitude) and one of larger cave bears from Gamssulzen Cave (1,300 m), situated approximately 10 km apart in the Austrian Alps (Figure 1A). We find no evidence of mitochondrial gene flow between these caves during the 15,000 years when they were both occupied by cave bears, although mitochondrial DNA sequences identical to those from Gamssulzen Cave could be recovered from a site located about 200 km to the south in Croatia. We also find no evidence that the morphology of the bears in the two caves changed to become more similar over time. We suggest that the two cave bear forms may have represented two reproductively isolated subspecies or species.  相似文献   
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