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Biotechnology Letters - Tumor suppressor miRNAs, miR-15a and miR-16–1, with high-specificity and oncogenic targeting of Bcl-2, can target tumor tissues. Disadvantages of the clinical...  相似文献   
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Body Area Networks (BANs) consist of various sensors which gather patient’s vital signs and deliver them to doctors. One of the most significant challenges faced, is the design of an energy-efficient next hop selection algorithm to satisfy Quality of Service (QoS) requirements for different healthcare applications. In this paper, a novel efficient next hop selection algorithm is proposed in multi-hop BANs. This algorithm uses the minimum hop count and a link cost function jointly in each node to choose the best next hop node. The link cost function includes the residual energy, free buffer size, and the link reliability of the neighboring nodes, which is used to balance the energy consumption and to satisfy QoS requirements in terms of end to end delay and reliability. Extensive simulation experiments were performed to evaluate the efficiency of the proposed algorithm using the NS-2 simulator. Simulation results show that our proposed algorithm provides significant improvement in terms of energy consumption, number of packets forwarded, end to end delay and packet delivery ratio compared to the existing routing protocol.  相似文献   
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Molecular Biology Reports - Alhagi Gagnebin (Fabaceae: Hedysareae) is a small genus of shrubs or subshrubs distributed in temperate and tropical regions of Asia, Europe, and Africa. The exact...  相似文献   
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In order to better understand the contribution of the knotted folding pattern to the enzymatic and mechanical properties of carbonic anhydrases, we replaced Gln-253 of bovine carbonic anhydrase II with Cys, which allowed us to measure the mechanical strength of the protein against tensile deformation by avoiding knot tightening. The expressed protein, to our surprise, turned out to contain two conformational isomers, one capable of binding an enzymatic inhibitor and the other not, which led to their separation through affinity chromatography. In near- and far-UV circular dichroism and fluorescence spectra, the separated conformers were very similar to each other and to the wild-type enzyme, indicating that they both had native-like conformations. We describe new evidence which supports the notion that the difference between the two conformers is likely to be related to the completeness of the C-terminal knot formation.  相似文献   
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The objective of this study was to evaluate the protein profiles of seminal plasma in buffalo bulls and to examine their correlation with semen characteristics. Semen of 10 buffalo bulls were collected by a bovine artificial vagina. Semen characteristics (motility, morphology, viability and concentration) were recorded. A part of the semen sample (1 ml) was diluted by tris-egg yolk-glycerol extender, packed in French straws and was frozen in liquid nitrogen. The straws were later thawed and semen characteristics were compared with those of the fresh semen. Seminal plasma was harvested by centrifugation; treated with cold ethanol and then, underwent SDS-polyacrylamide gel electrophoresis (PAGE). Twenty five protein bands were identified on the gel, of which those of <35.5 kDa were prominent (72% of the bands). Of these protein fractions, 24.5 kDa was significantly correlated with sperm progressive motility in fresh and viability in frozen-thawed semen while 45 kDa bands were correlated with abnormal morphology in frozen-thawed semen; 55 kDa protein fractions were correlated with sperm viability of fresh semen. Progressive motility, viability and abnormal sperm morphology of frozen-thawed semen were highly correlated with these parameters in the fresh semen. In conclusion, seminal plasma protein fractions in buffalo bulls are similar to those reported in other animal species and have some correlations with semen characteristics before and after freezing.  相似文献   
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Viral contaminations of biopharmaceutical manufacturing cell culture facilities are a significant threat and one for which having a risk mitigation strategy is highly desirable. High temperature, short time (HTST) mammalian cell media treatment may potentially safeguard manufacturing facilities from such contaminations. HTST is thought to inactivate virions by denaturing proteins of the viral capsid, and there is evidence that HTST provides ample virucidal efficacy against nonenveloped or naked viruses such as mouse minute virus (MMV), a parvovirus. The aim of the studies presented herein was to further delineate the susceptibility of MMV, known to have contaminated mammalian cell manufacturing facilities, to heat by exposing virus‐spiked cell culture media to a broad range of temperatures and for various times of exposure. The results of these studies show that HTST is capable of inactivating MMV by three orders of magnitude or more. Thus, we believe that HTST is a useful technology for the purposes of providing a barrier to adventitious contamination of mammalian cell culture processes in the biopharmaceutical industry. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009  相似文献   
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The plant traits that drive ecosystems: Evidence from three continents   总被引:4,自引:0,他引:4  
Question: A set of easily‐measured (‘soft’) plant traits has been identified as potentially useful predictors of ecosystem functioning in previous studies. Here we aimed to discover whether the screening techniques remain operational in widely contrasted circumstances, to test for the existence of axes of variation in the particular sets of traits, and to test for their links with ‘harder’ traits of proven importance to ecosystem functioning. Location: central‐western Argentina, central England, northern upland Iran, and north‐eastern Spain. Recurrent patterns of ecological specialization: Through ordination of a matrix of 640 vascular plant taxa by 12 standardized traits, we detected similar patterns of specialization in the four floras. The first PCA axis was identified as an axis of resource capture, usage and release. PCA axis 2 appeared to be a size‐related axis. Individual PCA for each country showed that the same traits remained valuable as predictors of resource capture and utilization in all of them, despite their major differences in climate, biogeography and land‐use. The results were not significantly driven by particular taxa: the main traits determining PCA axis 1 were very similar in eudicotyledons and monocotyledons and Asteraceae, Fabaceae and Poaceae. Links between recurrent suites of ‘soft’ traits and ‘hard’ traits: The validity of PCA axis 1 as a key predictor of resource capture and utilization was tested by comparisons between this axis and values of more rigorously established predictors (‘hard’ traits) for the floras of Argentina and England. PCA axis 1 was correlated with variation in relative growth rate, leaf nitrogen content, and litter decomposition rate. It also coincided with palatability to model generalist herbivores. Therefore, location on PCA axis 1 can be linked to major ecosystem processes in those habitats where the plants are dominant. Conclusion: We confirm the existence at the global scale of a major axis of evolutionary specialization, previously recognised in several local floras. This axis reflects a fundamental trade‐off between rapid acquisition of resources and conservation of resources within well‐protected tissues. These major trends of specialization were maintained across different environmental situations (including differences in the proximate causes of low productivity, i.e. drought or mineral nutrient deficiency). The trends were also consistent across floras and major phylogenetic groups, and were linked with traits directly relevant to ecosystem processes.  相似文献   
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Molecular Biology Reports - Rhabosciadium aucheri is an Iranian endemic herbaceous species that grows in the west, center, and south regions of Iran. In the present study, genetic variation of 70...  相似文献   
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