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Microbiology - Comparative study of methanogen diversity and potential activity of different methanogenic pathways in the sediments of young thermokarst and mature polygenetic Yamal lakes was...  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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The present situation in sexually transmitted diseases (STD) in the Republic of North Ossetia-Alania is characterized as unfavorable. Morbidity in different nosological forms has been found to show different tendencies. The causes of elevated morbidity in STD observed in recent years have social, economic, psychological, ethical and moral, rather than medical character. The main trends in the improvement of epidemiological surveillance on STD have been determined.  相似文献   
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The present epidemiological situation in diphtheria in the Republic of North Ossetia (Alania) is analyzed. The data on diphtheria morbidity and lethality are given. The present stable situation resulted from mass immunization of the adult population which ensured the level of vaccination coverage reaching 87% in 1995.  相似文献   
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Journal of Mammalian Evolution - We studied the relationship between the variability and contemporary distribution of pelage phenotypes in one of most widely distributed felid species and an array...  相似文献   
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The depth of two‐photon fluorescence imaging in turbid media can be significantly enhanced by the use of the here described fluorescence detection method that allows to efficiently collect scattered fluorescence photons from a wide area of the turbid sample. By using this detector we were able to perform imaging of turbid samples, simulating brain tissue, at depths up to 3 mm, where the two‐photon induced fluorescence signal is too weak to be detected by means used in conventional two‐photon microscopy. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
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