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931.
Molecular Biology Reports - Although cognitive impairment (CI) is classically associated with aging, it has been proposed that neurological pathologies may increase the risk to suffer CI. Despite...  相似文献   
932.
Molecular Biology Reports - According to the stem cell theory for cancer, hepatocellular carcinomas are sustained by a group of cancer stem cells (CSCs) which are responsible for resistance to...  相似文献   
933.
Mycopathologia - Candida species are common in the human oral microbiota and may cause oral candidiasis (OC) when the microbiota equilibrium is disturbed. Immunosuppressed individuals are...  相似文献   
934.
Plant Molecular Biology Reporter - Legumes form symbiosis with rhizobia, which fix nitrogen for the benefit of host plant in return for carbon resources. Development of this unique symbiosis in...  相似文献   
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Evidence regarding the ability of agroforests to conserve biological diversity has been mixed; they tend to maintain avian communities with species richness similar to that of undisturbed forest ecosystems but generally do not completely preserve community composition. Using a combination of occupancy modeling and non-metric multidimensional scaling on point-count data, we assessed changes in avian community diversity and composition along a successional gradient in traditional Lacandon Maya agroforests and compared them to protected areas in the region. Bird species richness and diversity in Lacandon agroforests peaked in early secondary forest stages. These agroforests' mean Shannon–Weiner diversity was 5% higher than that of nearby protected areas, but their species richness was similar. Community composition in Lacandon agroforests changed throughout succession, with earlier stages supporting communities distinctly characterized by generalist species, while subsequent, less-intensively managed stages tended to support more forest-dwellers. The bird community observed in even the most mature secondary forest stages in Lacandon agroforests differed from that of undisturbed rain forest ecosystems. These results demonstrate the potential of traditional Lacandon agroforestry management to conserve avian biodiversity while ensuring food sovereignty for farmers. However, because the community composition of early-successional stages was different than later stages, shortening fallow cycles and reducing forest cover to increase agricultural production will limit the species this system can support. This study illustrates the value of incorporating traditional agroecosystems into conservation planning as well as maintaining protected areas, because the latter serve as refugia for species that require undisturbed forest habitat in an agroecological matrix.  相似文献   
939.
Hydrobiologia - Pithecopus rusticus is an endemic amphibian restricted to the type locality, in southern Brazil, and possibly endangered to extinction, due to habitat degradation. However, an...  相似文献   
940.
Hydrobiologia - Due to an unfortunate turn of events, the incorrect caption of Fig. 2 appeared in the original publication. Figure 2 and its correct caption is published here and should be treated...  相似文献   
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