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11.
Oral pathogens have created a menace in recent years due to biofilm formation and antimicrobial drug resistance. The current treatment strategy works well with antibiotics. However, constant use of antibiotics creates a selective pressure, which increases adaptability of the pathogens. Therefore, it is of interest to analyze the potential targets of genistein in dental pathogens using computer aided prediction tools.  相似文献   
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Background  

Annotation of sequences that share little similarity to sequences of known function remains a major obstacle in genome annotation. Some of the best methods of detecting remote relationships between protein sequences are based on matching sequence profiles. We analyse the superfamily specific performance of sequence profile-profile matching. Our benchmark consists of a set of 16 protein superfamilies that are highly diverse at the sequence level. We relate the performance to the number of sequences in the profiles, the profile diversity and the extent of structural conservation in the superfamily.  相似文献   
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Background  

Existing cut-offs for fasting plasma glucose (FPG) and post-load glucose (2hPG) criteria are not equivalent in the diagnosis of diabetes and glucose intolerance. Adjusting cut-offs of single measurements have not helped so we undertook this project to see if they could be complementary.  相似文献   
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The cerebellum maintains balance and orientation, refines motor action, stores motor memories, and contributes to the timing aspects of cognition. We generated two mouse lines for making Cre recombinase-mediated gene disruptions largely confined to adult cerebellar granule cells. For this purpose we chose the GABA(A) receptor alpha6 subunit gene, whose expression marks this cell type. Here we describe mouse lines expressing Cre recombinase generated by 1) Cre knocked into the native alpha6 subunit gene by homologous recombination in embryonic stem cells; and 2) Cre recombined into an alpha6 subunit gene carried on a bacterial artificial chromosome (BAC) genomic clone. The fidelity of Cre expression was tested by crossing the mouse lines with the ROSA26 reporter mice. The particular alpha6BAC clone we identified will be valuable for delivering other gene products to cerebellar granule cells.  相似文献   
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We investigate physiological mechanisms behind the convergent evolutionary loss of seed dormancy in plant lineages, focusing on mangroves as a model system. More than 60 angiosperm families, including several mangrove taxa, contain species with seeds that are intolerant of drying and do not undergo dormancy. These desiccation-intolerant species occur with disproportionate frequency in wet or coastal tropical habitats. In plants, the hormone abscisic acid (ABA) coordinates both the development of desiccation tolerance during the onset of seed dormancy and whole-organism responses to flooding. Thus, changes in ABA levels and/or modes of action in different plant compartments are implicated in the repeated evolutionary loss of seed dormancy among species of wet habitats. We compare ontogenetic dynamics of ABA levels in embryonic, maternal, and mature vegetative tissue of four phylogenetically independent pairs of related viviparous mangroves and nonviviparous nonmangroves. We demonstrate that ABA levels are consistently lower in embryos of viviparous mangrove taxa than embryos of nonmangrove, nonviviparous sister taxa. In contrast, elevated tissue concentrations of ABA characterize leaves of all mangrove species tested, while ABA levels in maternal tissues vary among mangrove species. These commonalities suggest a functionally important trade-off between the maintenance of embryonic development and the adjustment of the parent tree to salinity stress. This study yields comparative data on seed physiology in naturally occurring desiccation-intolerant species, for which these data are currently scarce, and demonstrates a potentially significant role of phytohormones in the evolution of plant life histories.  相似文献   
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Background  

The highly pathogenic H5N1 is a major avian pathogen that crosses species barriers and seriously affects humans as well as some mammals. It mutates in an intensified manner and is considered a potential candidate for the possible next pandemic with all the catastrophic consequences.  相似文献   
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